One other note: For some designs, empty space can also put components with high interference like transformers away from critical areas of the device to avoid noise, and in some cases empty space helps isolate components from excessive heat.
Another reason for an amp case to be large is to do with ventilation and air flow. Many components get hot and keeping the components around them cool will extend their life.
I remember this in the old Sunn Coliseum bass amp; there were warning not to thouch the heat sinks or power output transistors.This is not so much of an issue in class D amps.
17" wide audio equipment became a "standard" so it could fit, either on a shelve or with front mounting "ears" in a standard 19" rack. The 19" rack format with rack-units "RU's" of 1.75 inches was established as a standard by AT&T in 1922. The 19" rack format has remained constant while the equipment mounted in it has changed over the decades. The 19" rack is widely used throughout the telecommunication, computing, audio, video, entertainment and industries.
@@TheElverma I like the story that relay racks originated in railroad switching yard control systems. Wiki says there's no evidence they were standardized before 1922 which is not surprising. AT+T needed lots of relays to connect phone calls and the railroads already had the hardware, using racks of relays to remotely control switches in rail yards. AT+T didn't invent it, they just standardized it.
Marketing is critical to sales. I see something very similar in the tire industry. Ever wonder why a high performance tire may cost four, even five times as much as a standard one? The tire dimensions, tooling, labor force and most parts are the same. Yes, some ingredients are more expensive. But definitely enough to justify such a high cost. The reason why high performance tires cost so much is because most people believe they should. Marketing.
If you want to see empty inside. Check out mini stereos from the 90s, the all in one units with tape, CD and tuner. There’s a few circuit boards and the rest is completely empty.
Our Knock Knock test we did was to do with throwing a newly finished piece of equipment down several flights of stairs (test sample and fully ready for delivery) just to see how it would withstand postage! Speaks volumes about our UK postage delivery services :)
To some extent , Transistors still have to deliver both Voltage and Current enough to drive the speakers and there is a Physical limit to the size of them to be able to deliver , after all byproduct is heat and it take a certain amount of size to dispose this combined with a good big heatsink too . Even smaller you make the component even less power they can handle , it is physics . Big heavy duty amplifiers with big strong transistors and heatsinks combined with a power supply that can deliver the voltage required with enough ampere is of course less prone to clipping and thus produce much more clean signal at high output compared with a typically small system with socalled same WATT number . A 300 watt amplifier with small transistors and little powersupply that cant deliver enough ampere will of course be clipping and most often can NEVER reach the socalled 300 watt in more than a few micro seconds . Where an Amplifier there is constructed with transistors big enough to handle the load and a power supply that can deliver more than just a few ampere can run this power continurly thus at same measurement methods it of course spit out much much more Watt in the same micro second ,, but the 300 watt is constant and to do this you cant just squice in some small micro component and call it a day . ( If that wasnt true then nobody would still produce those big heavy amplifiers ) Those small class D with switch mode is a HYPE and as we all know a Hype is SELLING and compare this with very CHEAP constuction / components and you have a BIG PROFIT ..
@@kennethsrensen7706 totally agree with you, no replacement for displacement (speaking in car terms) Also manufacturers need to stop running components in equipment to their limits most of the time, no room for error. If it is cooking hot at idle then it's not going to take much to push it over the edge and go poof!
@@kennethsrensen7706 And yet my 5kg class D power amp in my living room utterly destroyed the 25kg Arcam amp rated at a true 200watts per channel. Not even close. I sold the Arcam within days. Truly feeble sounding next to the Class D
I took apart a Sony phone to fix a broken wire only to find it had a piece of cast iron in the handset. Took it out, felt cheap as hell. Put it back in, yup, better quality feel.
When mt dad transitioned from a music centre to components in the mid 70s he did a fair bit of research before reaching his final choice. He said that the thinner a unit was the less substantial the components inside were. He also directly attributed weight to quality. That has definitely rubbed off onto me I'm afraid.
Never new why products were sized the way they were. Thanks for the explanation. I remember as a teenager going into audio salons and drooling over the components in the 70's. Audio racks were really cool.
Standard case sizes make installers happy. "Heavy" has always been a good seller of electronics because it was unavoidable for most of design history. Put in one heavy design element and everything else has to made heavy to compensate. "Broadcast" turntables, Marantz flywheel tuning, and iron core output transformers, come to mind of designs that set trends. Until Class D amplifiers came along, I judged an amplifier by its physical weight. There was a fad in the 1960's when hi-fi components were installed in cutouts in the walls.
The Earliest recollection of Exactly that Same Test that I Believe Started it: The Two Stereo Companies were Scott & Fisher !! The event happened prior to me working for one of them in 1972.
When I bought my first ‘proper’ amplifier (Arcam Alpha 10) about 22 years ago it definitely passed the knock-knock test. It felt like I was picking up a block of lead and it’s built like a brick. The heat it generated when powering the front mains on my home cinema setup was significant so it got extra room in my rack. It has a large ‘air-space’ on one side, presumably in part to ventilate that heat. Today, it’s semi-retired, replaced by a Denon AVR - which passes KK test - but I could never let it go. Such a lovely piece of kit. I just want to find another use for it. Suggestions welcome. By comparison, my 40 year-old Denon CD player has almost twice the internal volume, mostly air, and feels plasticky. Fails KK test - plays beautifully though.
The Arcam alpha 10 was a wonderful amp in its time. Handily beats far more expensive amps like bryston B60 & Accuphase 203. To me of cos. YMMV. Later Arcams such as A85 & A38 were also very good value for $$. Just make sure the gain in these amps are set to the max otherwise they will sound weak & lacking in dynamics.
This is why I love my Bang & Olsen bowmaster 6500 with penta 3 speakers the amplifiers built into them and sound that you have never heard if you've ever heard these speakers before. I have my set of pentas that I got over 20 years ago that were built in 89 and they still run a perfectly today as it did back then. But then again you expect that kind of quality from a manufacturer like Bang & Olsen. When I first heard Pink Floyd on my new system that I got back in the late '90s it sounded like I was hearing Pink Floyd for the first time. Notes and sounds that I never heard before we're coming out of my speakers that made it sound that much better. These speakers never crack and you just turn them up louder and louder and the louder you go the more insane you get. They penetrate through walls like they aren't even there. The further you are away from it the better it sounds it seems. But even turn down to two you can have a hard time hearing if you're on the phone with somebody. I believe it goes up to 60 but I've never had it above about a 56 because it's just too loud. I don't believe they ever made anything 17x19. They always did things their own way and it shows with her quality. Did I mention I had to spend $5,000 to buy the last set of Penta speakers sold in United States... Back in their Mission Valley San Diego California store. Which was right across the hall from a Bose stereo store which if you walked into both of them you could unmistakably hear the quality of the Bang side and the Bose sounded like an empty hollow tube
The 19” was standardized by the EIAJ if I’m not mistaken. Most of my equipment is rack mount. Only real drawback is you have to have supports at the rear of the equipment and a lot of manufacturers don’t supply rack mount “ears” for their equipment.
As an audio guy, I am continuously frustrated with the way that people “hear with their eyes”. I deal with it on every level and in every situation. I learned from doing corporate work that the sound is only important when there’s an obvious sonic problem that can be easily heard by a layman. At all the other times, looks and general appearances matter more than anything.
Yep, true on 19" rack. Even my standard ole Onkyo Surround receiver measures just a tad over 17" across. I also use a steel rack too for other gear. If I fabricated adapter "ears" for the receiver, it would probably fit in the rack!
I got the big speakers hooked at the moment: You could hear the weight of the smaller unit as you placed it back on the table. It had that 'knock knock' approval sound.
I use the "Knock Knock Test" on speakers, but not only the top, the middle of the back, the sides, etc. You don't want the ones that sound like a wooden shipping crate. You want the ones that sound like a block of cement. The ones the drivers won't thump and make sound like the box are the ones you want. Yes they are heavy and expansive to ship. Try it next time in your local high end audio or home theater store.
Years ago, my company made the tools to produce a plastic housing for a Pioneer power amp. The housing had some weird features on the inside. I questioned what they were being used for. The answer was that they held section of rebar. The heavy metal rods used to strengthen concrete structures. They were using rebar to add weight to the power amp. Light weight amps didn't sell as customers expected a power amp to be heavy to really produce high power output. Total BS.
Nearly all "professional" sound equipment is based on standard dimensions and usual is listed as per how many Rack Units or RU's it is. So you will see 1RU, 2RU etc. They also have "wings" to allow them to be mounted into the carrying rack. A lot of consumer audio still follow the same dimensions.
The knock knock test, that's a new one, never thought of doing that to an amp. My favourite is to lift one corner and see if the chassis flexes, i.e. one foot of the table, the other three still on the table is a fail.
I have 3 pieces of InterM 500 amplifiers. And they are convection cooled! And there is space inside. And the bottom and the top plate is open. Plenty of slot's on the sheet! Then I have an InterM 1000. There is no place what'soewer. But it's cooled with fans!!
A lot of amplifiers today use a switch mode power supply negating the need for a large heavy power transformer, SMD components that take up much less space, and much more efficient Class D amplifier modules negating the need for bulky heatsinks. In fact, PS Audio's own Stellar S300 is a perfect example, with 140 watts per channel, weighing just 13 pounds, and with lots of extra space inside the chassis.
The other thing that "makes for more empty space" is that components are way smaller than they use to be. For example, tuner sections in stereo receivers are no where near as big as they use to be. Also, most amplifiers don't use the old TO3 transistor banks anymore. They were big and required BIG heatsinks.
@@dizzywow ... yes, but in those days you needed size just for the heat handling ability. Basically the same reason a large radiator in your home can deliver more heat to the air.
Both my reciver and my stereo/power amp (dedicated pwr amp inputs) are stuffed full😝 The stereo amp even has two power supplies since it's built as a dual mono.
I know no one that listened to great sounding gear, was ready to buy, but chose not to do so based on a "knock knock" test. There are people that buy without listening. So perhaps they do the "knock knock" test? Paul, your Aesthetix Calypso has a light cover on it. And you have praised that pre-amp. It changed your mind, such that you no longer connect your CD player directly to your amps. I am not buying that someone that auditioned that that pre-amp would decline to purchase it, due to its light-weight cover. In a department store, that seems reasonable. As far as I know, PS Audio gear is not sold in department stores.
The knock knock test reminds me of the computer industry in the late 70s to early 80s, where computers had to be big cabinets full of equipment, but the industry was starting to use desk top systems. The owner of the computer company I worked for said we don't make furniture, and missed the boat and the industry outran his tiny mindset, and he went out of business.
A full-featured amplifier could fit on a circuit board the size of a 3 X 5 card. It just won't have much amplification. Powering woofers etc. creates heat.
I think you didnt get what he ask about . Hm , That remind me about a similary experience a few years ago . I was to buy an extra amplifier for my studio . I was in several different shops and in one particulary shop I found a japanese amplifier in a big cabinet , but when I looked inside it through the holes in the top there was litterly NOTHING inside , just bare empty cabinet and the smallest tiny circuit board in the corner . That circuitboard could easy fit into a 10 * 10 * 5 cm little plastic box and then call it a day . It turn out it was a class D with switch mode powersupply . Beside it was an unknown Chinese branded solid state amplifier at same size but when I looked inside through top holes , it was totally filled up with big transformers , capasitors and big heatsinks with many heavyduty transistors ect . I tried lift them both and the Chinese one was really heavy too the other was only the thin cabinet and it litterly was both thin and flimsy but the chinese was thick and strong . I listened to both and Just as I expected the Chinese one sounded GREAT GREAT and the other sounded thin and weak . It turned out the Chinese was a Class A/B amplifier and I ended up buying it ( They both cost the excact same ) I still use it today and it is really strong and sound so great , never regret this purcase . I did some digging into the japanese one and found out that if you buy all component seperate and assemple it by yourself then the cost will just be around 2 percent of the cost in the shop .... They make enormous PROFIT by hyping up those super cheap produced amplifiers and selling them at same price as the NORMAL good ones with high quality components . NO Doubt those Class D with switch mode powersupply is extremely CHEAP to produce and the PROFIT is the highest of them all ... Im NEVER going to buy such cheap quality NEVER , Im very happy with my Chinese amplifier and the components is great quality and it have lots of power too . The Class A/B solution is great and rock solid . ( and the box is NOT filled with air , its NOT an empty box ) I guess that is what he mean ( That was my experience )
in the 90's I worked on CD players and VCRs. One top of the line denon CD player that crossed my bench was cheap plastic inside but it had a 1/8" thick steel plate spot welded to the bottom cover plate.
I recall seeing some impressive looking car audio amps back in the early 90s. Manufacturers were all trying to out-impress each other. I saw a few of the cheaper ones opened up and was just shocked at how little was inside and how crappy the components in it were.
Have you seen Derek BigD (Williston Audio Labs) on TH-cam, where he tested one of those "reverse cheater amps" on the amp dyno? I think it was a Pyramid model from the early 90's or late 80's. Big looking amp, but when it got opened up, the inside components were a joke. A tiny circuit board on one side, with a bunch of long wires soldered on to reach the inputs and the dials on the other side
I purchased, online Ebay, a duel 8" speaker with duel horn tweeters Karaoke bluetooth and aux. Typical setup. It sounded flat and horrible. After opening it up, speakers had tape shocks no foam rubber, and NO tweeters in the molded horns at all. I was shocked. It needs an amp but I haven't learned how to build one to add on. Yet. Lol
A lot of electronics have gone from discrete components to semiconductor modules. I think these came out of car audio but I’ve seen a few home audio-video receivers have them too. Just a big black chip that is a 60 watt amplifier. Line level in, 24 Vdc and outputs to the speakers. Designed to be mounted on a heat sink. Smaller than a car key fob. This takes the place of a much bigger circuit board.
You didn't mention this, but it is important to remember that in order to maximize audio performance and minimize noise and distortion, certain of the components must be kept physically distinct and as far as practical from the other. Any component in the signal path can receive interference from a component in the power supply path - so a careful audio engineer designing a new device has to make isolation of the signal and power supply paths an extremely high priority. Many times the best way to accomplish this is just with a little extra distance between components.
The SET monos I build - have a very low parts count in a small box. The box is 5 mill steel. They feel weighted. They sound right when driving the right drivers.
Yeah mostly empty space because of highly integrated circiuts. However, even higher powered audio amp chipsets should be a little more substantial just to handle the power passing through through and probably heat sinks to dissipate heat energy that doesn't come out as sound energy.
I recently bought a tuner and true to form I had to have a look. Turns out there's just a fat chip on the little front panel PCB, a few tact switches, an LCD AND NOTHING ELSE! So where's the tuner? It's all in software and the entire chassis is empty save for a tiny little SMPS at the rear by the massive AC inlet. And it works great as tuners go. Why have rows of LC stuff when you don't have to?
Funny you mention the air / empty space. I have a Phase Linear 400 and even with the reduced depth as compared to a Pioneer Spec series, there's more empty real estate inside than the Pioneer. That Spec amp is chock full to the brim. BTW, they both pass the KK test and the weight test. As one friend said, these things are like a window AC unit with handles.... and a power cord to match.
Seem like new generation don't have need for high quality sound! In the 80's most young people know brand for good high quality sound and we save money to buy it. Today they just listen to phone speaker or headphones. I think they missing a lot.
Wasn't there also that old classic theory of trying to reduce the number of parts or components to try and reduce any artifice or sonic interference in the signal path too?
It is actually in reverse. You will still find the better and more expensive hardware bragging about discrete components instead of ICs. Thermal noise crosstalk when multiple devices are on one silicon! Point to point wiring over circuit boards. Less capacitance and path crosstalk....
Another reason for space is that electrical components got smaller and more powerful. Think back to the Crown DC 300. Large E-frame transformer, large low-density capacitors, TO3 transistors, etc. Transformers are (for the most part) smaller toroidal transformer, Higher density caps, (switch-mode supply in some lower grade amps) TO3P or TO220 transistors, etc.
Really awesome amp right there very nice Paul. I have a Nakamichi PA-7, What? lol. Yes they are, becoming smaller because a lot are implementing switcher amps with caps instead of transistors and massive transformers. Less heat, no noise and the winning part: cheap to make. Though I’ll take my transformers and noise any day over a class ‘D’ switcher. Just not a true ‘amp’, no soul and ‘sim’ sounding. Great video, long live two channel.
@@peterlarkin762 Hey Peter, outstanding for its age. Very dynamic amp, (some have said ‘veiled’, but that’s just slander imo and using Audioquest Evergreen for signal) love the older stuff that’s built like real equipment. Nice to have something Mr. Pass worked on, what a talent. It was part of Nakamichis flagship line back in 1988, a good friend here in Daytona that owns ‘Stereo Types’ was upgrading in 2000, and wanted 3k for the amp, pre and tuner. I gave him the “So is that the price for your FRIEND” line, and he looks at me and says: “Go get me 2k cash before I change my mind” with a smile lol. Not a bad day at all at that point, pretty righteous for a decent system. Thanks for your interest Peter, enjoy sir.
Thanks Randy, man! Think it's an amp on my 'see it, buy it' list now. Honestly, discrete power amp circuitry has not evolved a huge amount since that was produced. And it's such a beautiful chassis. Rare here in Ireland. A PA5 would suffice. You got a seriously good deal for the stack! I've also been researching the amazing Nakamichi Dragon CT turntable and it's self centering mechanism. Ingenious. Best wishes and peace. Peter.
How many Class D have you heard?? I've been listening to amps for years (35 +) class A class A/B as that was all that was available I'm currently using a tube preamp with a class D power amp (600 wpc). It utterly destroys any of the traditional Amps I've had ( creek, Arcam naim Denon etc etc) I'll never buy another class A classA/B. Why do I feel like this ? Why does this combo sound so superior to anything else I've ever owned??
👍 Even though he did not mention class D amp, we can imagine the class D amp in the standard chassis looks so "empty". Chinese manufacturers make very compact class D amplifiers like SA-98E ignoring the standard 17"(430mm) width, with an external AC/DC adapter.
It's the representation of audiophiles. There's lots of stuff to entice you to spend money on things, but not as much as you think on the inside XD I use compact electronics, but still use big speakers lol
Topping and others are turning this 17" thing on its head... Can fit separates from Topping (DAC , Preamp and Amp) all inside of a 17" 2U case with arguably better specs
The last Topping amp I bought sounded worse than the Dayton Audio amp that used the same chip. It didn't sound too bad, but not worth the extra $ over the cheaper one. More of a complement to the parts express folks than anything else I guess. I think both models are now discontinued.
Strange that this guy didn't even mention airflow as one of the reasons. Also (with some) the lack of space being the main reason for amp destruction! 😂
Once I looked inside a musical fidelity amp, and that one had a transformer in one corner, a green circuit board in another and the rest was just air and heatsink on the outer edges.
The knock knock test really made me laugh…..i am also from singapore & i recall in the 70s & 80s, many ignorant audiophiles back then judge an amplifier by its weight. The heavier they weigh, the better. I fondly remember how a group of older audiophiles went totally nuts when my puny 3.5kg Creek 4140 integrated amp massacred a humongous 50kg pioneer receiver in terms of bass control, dynamics & sound quality. They couldn’t believe what they heard. Scratched their heads real hard. 2 days later i repeated the same trick with another puny amp in the form of Mission Cyrus 2. Today i own LFD LE 3 which is also puny & has plenty of underutilised real estate inside. But i far prefer its sound to many 30 to 50kg behemoths. Pick your poison!
A lot of old Amps need a lot of cooling special the first class a/b Amps. The big weight come from cooling heatplate and the travo ring . After a/b with Mosfet the amp las weight and cooling need IT. Later airflow by a fan and again lower weight . After dat class-d amp what do not really need a lot of cooling. Its how a/b VS d amp works. A/b Amps have always power on the speaker. A class-d and somtimes digital d amp . Can set the power of to your speakers. No sound means no Heat . Than real old class a Amps. Well that have to Heat u for a good sound. Its Just what the type amp it is.
Standard sizes of cases started to get too big for standard components due to miniaturisation. When I purchased my first stereo set in the 80s, it was the standard 19“ size. The rack had to be that wide because of the vinyl record player on top of it. But then CDs were about to take over, and there wasn’t any need for big cases any longer. So Sony decided to produce smaller sets. But they still had to provide stereo sets of the ‚classic' size. What did they do? Produce the smaller form factor PCBs, mount them into the big cases and leave half the case empty.
You would think that by adding space in between components. That it would help reduce crosstalk. If thats the word im looking for. One reason why separates and external power supplies can have lower noise floor. Some people may call it fog.
Coming from the semiconductor field, electronics have become more efficient, and therefore smaller, while keeping the shell the same, so over the years its gonna get worse. I remember back in 1986 while stationed in NY i bought my first CD radio built by JVC, it was ~$100 with detachable speakers, and "chock full of parts, It was a solid Japanese radio, some one else bought a Koss or something like it but it was Chinese. When he opened his up and found a few electronic boards with metal plates giving the false impression of a quality radio, but was junk that caused more interference than it was worth.
One other note: For some designs, empty space can also put components with high interference like transformers away from critical areas of the device to avoid noise, and in some cases empty space helps isolate components from excessive heat.
So you do NOT need noisy- failure prone fans
But the con is cable length between the components increase
First thing that occurred to me especially with mc phono stages.... A missed opportunity?
Or maybe it's not as important as we think
🎶🤔🎶
It's like the three Stooges said: "Spread out!"
This was what I was thinking as well before he started, but did not broach the subject.
Another reason for an amp case to be large is to do with ventilation and air flow. Many components get hot and keeping the components around them cool will extend their life.
I remember this in the old Sunn Coliseum bass amp; there were warning not to thouch the heat sinks or power output transistors.This is not so much of an issue in class D amps.
17" wide audio equipment became a "standard" so it could fit, either on a shelve or with front mounting "ears" in a standard 19" rack. The 19" rack format with rack-units "RU's" of 1.75 inches was established as a standard by AT&T in 1922. The 19" rack format has remained constant while the equipment mounted in it has changed over the decades. The 19" rack is widely used throughout the telecommunication, computing, audio, video, entertainment and industries.
Rack unit. en.wikipedia.org/wiki/Rack_unit
@@TheElverma I like the story that relay racks originated in railroad switching yard control systems. Wiki says there's no evidence they were standardized before 1922 which is not surprising. AT+T needed lots of relays to connect phone calls and the railroads already had the hardware, using racks of relays to remotely control switches in rail yards. AT+T didn't invent it, they just standardized it.
NAD 208 and 218 THX comes to mind when you mention rack-mount
I loved your "knock knock test" anecdote. It cheered me up no end!
That "knock knock" test reminds me of how many people used to judge cassette players by how smoothly the transport door opened.
I was one of those guys!
As someone who works in IT, i love the rackmount like design
the T in RETMA was for telephone, where I got my start in a CO. IT still uses Telco terms (as well as 2 post racks) today
Marketing is critical to sales. I see something very similar in the tire industry. Ever wonder why a high performance tire may cost four, even five times as much as a standard one? The tire dimensions, tooling, labor force and most parts are the same. Yes, some ingredients are more expensive. But definitely enough to justify such a high cost. The reason why high performance tires cost so much is because most people believe they should. Marketing.
Paul I think you work hard but at the same time you must have a lot of fun doing what you doing kuddos Sir
If you want to see empty inside. Check out mini stereos from the 90s, the all in one units with tape, CD and tuner. There’s a few circuit boards and the rest is completely empty.
Our Knock Knock test we did was to do with throwing a newly finished piece of equipment down several flights of stairs (test sample and fully ready for delivery) just to see how it would withstand postage! Speaks volumes about our UK postage delivery services :)
We called it drop testing
@@zeusapollo8688 we call it " fed ex readiness "
Also as component parts are getting smaller it takes up less space for the same function and in some cases better performance.
To some extent , Transistors still have to deliver both Voltage and Current enough to drive the speakers
and there is a Physical limit to the size of them to be able to deliver , after all byproduct is heat and
it take a certain amount of size to dispose this combined with a good big heatsink too .
Even smaller you make the component even less power they can handle , it is physics .
Big heavy duty amplifiers with big strong transistors and heatsinks combined with a power supply that
can deliver the voltage required with enough ampere is of course less prone to clipping and thus
produce much more clean signal at high output compared with a typically small system with
socalled same WATT number .
A 300 watt amplifier with small transistors and little powersupply that cant deliver enough ampere
will of course be clipping and most often can NEVER reach the socalled 300 watt in more than a few micro seconds .
Where an Amplifier there is constructed with transistors big enough to handle the load and a power supply that can
deliver more than just a few ampere can run this power continurly thus at same measurement methods it
of course spit out much much more Watt in the same micro second ,, but the 300 watt is constant and to do this
you cant just squice in some small micro component and call it a day .
( If that wasnt true then nobody would still produce those big heavy amplifiers )
Those small class D with switch mode is a HYPE and as we all know a Hype is SELLING and compare this with
very CHEAP constuction / components and you have a BIG PROFIT ..
@@kennethsrensen7706 totally agree with you, no replacement for displacement (speaking in car terms) Also manufacturers need to stop running components in equipment to their limits most of the time, no room for error. If it is cooking hot at idle then it's not going to take much to push it over the edge and go poof!
@@J.Christ-man Yes thats so true : )
@Taco Totally agree : )
@@kennethsrensen7706 And yet my 5kg class D power amp in my living room utterly destroyed the 25kg Arcam amp rated at a true 200watts per channel.
Not even close. I sold the Arcam within days. Truly feeble sounding next to the Class D
I took apart a Sony phone to fix a broken wire only to find it had a piece of cast iron in the handset. Took it out, felt cheap as hell. Put it back in, yup, better quality feel.
When mt dad transitioned from a music centre to components in the mid 70s he did a fair bit of research before reaching his final choice. He said that the thinner a unit was the less substantial the components inside were. He also directly attributed weight to quality. That has definitely rubbed off onto me I'm afraid.
I love the knock knock story, I hadn't heard that one before Paul
😁🎧👍.
Never new why products were sized the way they were. Thanks for the explanation. I remember as a teenager going into audio salons and drooling over the components in the 70's. Audio racks were really cool.
Good thing solid state guitar amps don’t have to worry about the”knock knock” test!
Standard case sizes make installers happy. "Heavy" has always been a good seller of electronics because it was unavoidable for most of design history. Put in one heavy design element and everything else has to made heavy to compensate. "Broadcast" turntables, Marantz flywheel tuning, and iron core output transformers, come to mind of designs that set trends. Until Class D amplifiers came along, I judged an amplifier by its physical weight. There was a fad in the 1960's when hi-fi components were installed in cutouts in the walls.
The Earliest recollection of Exactly that Same Test that I Believe Started it: The Two Stereo Companies were Scott & Fisher !! The event happened prior to me working for one of them in 1972.
When I bought my first ‘proper’ amplifier (Arcam Alpha 10) about 22 years ago it definitely passed the knock-knock test. It felt like I was picking up a block of lead and it’s built like a brick. The heat it generated when powering the front mains on my home cinema setup was significant so it got extra room in my rack. It has a large ‘air-space’ on one side, presumably in part to ventilate that heat. Today, it’s semi-retired, replaced by a Denon AVR - which passes KK test - but I could never let it go. Such a lovely piece of kit. I just want to find another use for it. Suggestions welcome. By comparison, my 40 year-old Denon CD player has almost twice the internal volume, mostly air, and feels plasticky. Fails KK test - plays beautifully though.
The Arcam alpha 10 was a wonderful amp in its time. Handily beats far more expensive amps like bryston B60 & Accuphase 203. To me of cos. YMMV. Later Arcams such as A85 & A38 were also very good value for $$. Just make sure the gain in these amps are set to the max otherwise they will sound weak & lacking in dynamics.
I like a standard size for stacking, but I think the weight of something when you hoist it has intrinsic value all by itself.
For me in the past it was the Volume Knob. It had to feel like you were really moving something, big, valuable, heavy, made of metal.
So cool! Thanks for sharing your knowledge! I look forward to hearing more!
That must be at LEAST a 2000va transformer in that amp! Definitely 5u heatsinks in there!
Looks like a P15 power regenerator. The display and its size gave it away.
This is why I love my Bang & Olsen bowmaster 6500 with penta 3 speakers the amplifiers built into them and sound that you have never heard if you've ever heard these speakers before. I have my set of pentas that I got over 20 years ago that were built in 89 and they still run a perfectly today as it did back then. But then again you expect that kind of quality from a manufacturer like Bang & Olsen. When I first heard Pink Floyd on my new system that I got back in the late '90s it sounded like I was hearing Pink Floyd for the first time. Notes and sounds that I never heard before we're coming out of my speakers that made it sound that much better. These speakers never crack and you just turn them up louder and louder and the louder you go the more insane you get. They penetrate through walls like they aren't even there. The further you are away from it the better it sounds it seems. But even turn down to two you can have a hard time hearing if you're on the phone with somebody. I believe it goes up to 60 but I've never had it above about a 56 because it's just too loud. I don't believe they ever made anything 17x19. They always did things their own way and it shows with her quality. Did I mention I had to spend $5,000 to buy the last set of Penta speakers sold in United States... Back in their Mission Valley San Diego California store. Which was right across the hall from a Bose stereo store which if you walked into both of them you could unmistakably hear the quality of the Bang side and the Bose sounded like an empty hollow tube
Why are so many amplifiers empty inside? Maybe they’ve never found love….
Oh I like it, as good a reason as any Ha Ha.
The 19” was standardized by the EIAJ if I’m not mistaken. Most of my equipment is rack mount. Only real drawback is you have to have supports at the rear of the equipment and a lot of manufacturers don’t supply rack mount “ears” for their equipment.
As an audio guy, I am continuously frustrated with the way that people “hear with their eyes”. I deal with it on every level and in every situation. I learned from doing corporate work that the sound is only important when there’s an obvious sonic problem that can be easily heard by a layman. At all the other times, looks and general appearances matter more than anything.
Yep, true on 19" rack. Even my standard ole Onkyo Surround receiver measures just a tad over 17" across. I also use a steel rack too for other gear. If I fabricated adapter "ears" for the receiver, it would probably fit in the rack!
Great video! I love your passion for perfection in audio. Greetings from Argentina!
Hilarious idea: build in a tiny speaker and if someone knocks on a component two times, have it say "who's there".
Or better yet, "Cut that out!"
I think the question was referring to a comparison as to why some amplifiers have nothing in them and some have a ton of stuff….regardless of size
I got the big speakers hooked at the moment: You could hear the weight of the smaller unit as you placed it back on the table. It had that 'knock knock' approval sound.
I use the "Knock Knock Test" on speakers, but not only the top, the middle of the back, the sides, etc. You don't want the ones that sound like a wooden shipping crate. You want the ones that sound like a block of cement. The ones the drivers won't thump and make sound like the box are the ones you want. Yes they are heavy and expansive to ship. Try it next time in your local high end audio or home theater store.
Years ago, my company made the tools to produce a plastic housing for a Pioneer power amp. The housing had some weird features on the inside. I questioned what they were being used for. The answer was that they held section of rebar. The heavy metal rods used to strengthen concrete structures. They were using rebar to add weight to the power amp. Light weight amps didn't sell as customers expected a power amp to be heavy to really produce high power output.
Total BS.
Cause size looks like your getting more for your money, 50% psychology, 40% ventilation
and shielding and 10% components.
LOL, knock, knock test! That had me in stitches. Thanks.
That power supply 😍
Love the Knock Knock story! It's a thing almost everyone of us do (the knocking part) whitout even knowing why we do! 😂😂
On speakers. Never on amplifiers.
Nearly all "professional" sound equipment is based on standard dimensions and usual is listed as per how many Rack Units or RU's it is. So you will see 1RU, 2RU etc. They also have "wings" to allow them to be mounted into the carrying rack. A lot of consumer audio still follow the same dimensions.
I hope they don't change that, I still mix pro and consumer gear now and then, nice to have it all fit together.
The knock knock test, that's a new one, never thought of doing that to an amp.
My favourite is to lift one corner and see if the chassis flexes, i.e. one foot of the table, the other three still on the table is a fail.
I was going to say the same. Rack ears does not make it 'rackable' (without rails). Boo-Hiss on Pro LOOK
I have 3 pieces of InterM 500 amplifiers. And they are convection cooled! And there is space inside. And the bottom and the top plate is open. Plenty of slot's on the sheet! Then I have an InterM 1000. There is no place what'soewer. But it's cooled with fans!!
A lot of amplifiers today use a switch mode power supply negating the need for a large heavy power transformer, SMD components that take up much less space, and much more efficient Class D amplifier modules negating the need for bulky heatsinks. In fact, PS Audio's own Stellar S300 is a perfect example, with 140 watts per channel, weighing just 13 pounds, and with lots of extra space inside the chassis.
Just got a LEGACY iV2 AMP for my Legacy Focus SE full range speakers and it is astounding! I am totally sold on Class D with the latest ICE Modules.
The other thing that "makes for more empty space" is that components are way smaller than they use to be. For example, tuner sections in stereo receivers are no where near as big as they use to be. Also, most amplifiers don't use the old TO3 transistor banks anymore. They were big and required BIG heatsinks.
The size of the heat sinks has to do with the amount of power they must dissipate, not the size of the transistors.
@@dizzywow ... yes, but in those days you needed size just for the heat handling ability. Basically the same reason a large radiator in your home can deliver more heat to the air.
Both my reciver and my stereo/power amp (dedicated pwr amp inputs) are stuffed full😝 The stereo amp even has two power supplies since it's built as a dual mono.
Empty space also helps with heat dissipation. The air needs some room to move because 'thermodynamics'.
I know no one that listened to great sounding gear, was ready to buy, but chose not to do so based on a "knock knock" test.
There are people that buy without listening. So perhaps they do the "knock knock" test?
Paul, your Aesthetix Calypso has a light cover on it. And you have praised that pre-amp. It changed your mind, such that you no longer connect your CD player directly to your amps.
I am not buying that someone that auditioned that that pre-amp would decline to purchase it, due to its light-weight cover.
In a department store, that seems reasonable. As far as I know, PS Audio gear is not sold in department stores.
Great stories and info, thank you.
The knock knock test reminds me of the computer industry in the late 70s to early 80s, where computers had to be big cabinets full of equipment, but the industry was starting to use desk top systems. The owner of the computer company I worked for said we don't make furniture, and missed the boat and the industry outran his tiny mindset, and he went out of business.
A full-featured amplifier could fit on a circuit board the size of a 3 X 5 card. It just won't have much amplification. Powering woofers etc. creates heat.
I had an equiliser with 3 inch sliders. It was 3 RU's. It had all its electronics on a module the size of a pack of cards. 99% empty.
Knock knock test, lol makes me think of Jeff Rowland gear.
I think you didnt get what he ask about .
Hm , That remind me about a similary experience a few years ago .
I was to buy an extra amplifier for my studio .
I was in several different shops and in one particulary shop I found
a japanese amplifier in a big cabinet , but when I looked inside it through the
holes in the top there was litterly NOTHING inside , just bare empty cabinet and
the smallest tiny circuit board in the corner .
That circuitboard could easy fit into a 10 * 10 * 5 cm little plastic box and then call it a day .
It turn out it was a class D with switch mode powersupply .
Beside it was an unknown Chinese branded solid state amplifier at same size but when I
looked inside through top holes , it was totally filled up with big transformers , capasitors
and big heatsinks with many heavyduty transistors ect .
I tried lift them both and the Chinese one was really heavy too the other was only the thin
cabinet and it litterly was both thin and flimsy but the chinese was thick and strong .
I listened to both and Just as I expected the Chinese one sounded GREAT GREAT and
the other sounded thin and weak . It turned out the Chinese was a Class A/B amplifier and
I ended up buying it ( They both cost the excact same )
I still use it today and it is really strong and sound so great , never regret this purcase .
I did some digging into the japanese one and found out that if you buy all component
seperate and assemple it by yourself then the cost will just be around 2 percent of the cost
in the shop .... They make enormous PROFIT by hyping up those super cheap produced
amplifiers and selling them at same price as the NORMAL good ones with high quality components .
NO Doubt those Class D with switch mode powersupply is extremely CHEAP to produce
and the PROFIT is the highest of them all ...
Im NEVER going to buy such cheap quality NEVER , Im very happy with my Chinese amplifier
and the components is great quality and it have lots of power too .
The Class A/B solution is great and rock solid .
( and the box is NOT filled with air , its NOT an empty box )
I guess that is what he mean ( That was my experience )
Transformers need to be spaced far enough from the input stage to avoid hum.
There is also a certain amouth of space needed for air movement to dissipate heat.
in the 90's I worked on CD players and VCRs. One top of the line denon CD player that crossed my bench was cheap plastic inside but it had a 1/8" thick steel plate spot welded to the bottom cover plate.
Computers and research instrumentation also grew up on 19" racks...
I recall seeing some impressive looking car audio amps back in the early 90s. Manufacturers were all trying to out-impress each other. I saw a few of the cheaper ones opened up and was just shocked at how little was inside and how crappy the components in it were.
That flea market amp. A lot of those are Just 5 OR 10 watt RMS. Lol
Have you seen Derek BigD (Williston Audio Labs) on TH-cam, where he tested one of those "reverse cheater amps" on the amp dyno?
I think it was a Pyramid model from the early 90's or late 80's. Big looking amp, but when it got opened up, the inside components were a joke. A tiny circuit board on one side, with a bunch of long wires soldered on to reach the inputs and the dials on the other side
I purchased, online Ebay, a duel 8" speaker with duel horn tweeters Karaoke bluetooth and aux. Typical setup. It sounded flat and horrible. After opening it up, speakers had tape shocks no foam rubber, and NO tweeters in the molded horns at all. I was shocked. It needs an amp but I haven't learned how to build one to add on. Yet. Lol
great review!!!!!
The knock knock test:
if it doesn't inflame my arthritis it doesn't earn my tinnitus!
A lot of electronics have gone from discrete components to semiconductor modules. I think these came out of car audio but I’ve seen a few home audio-video receivers have them too. Just a big black chip that is a 60 watt amplifier. Line level in, 24 Vdc and outputs to the speakers. Designed to be mounted on a heat sink. Smaller than a car key fob. This takes the place of a much bigger circuit board.
Some older Sony receivers also had a second piece of sheet metal glued to the inside of the top cover.
In the 1970s your tuner and amplifier had to be deep enough front to back that you could put a turntable on top.
You didn't mention this, but it is important to remember that in order to maximize audio performance and minimize noise and distortion, certain of the components must be kept physically distinct and as far as practical from the other. Any component in the signal path can receive interference from a component in the power supply path - so a careful audio engineer designing a new device has to make isolation of the signal and power supply paths an extremely high priority. Many times the best way to accomplish this is just with a little extra distance between components.
The SET monos I build - have a very low parts count in a small box. The box is 5 mill steel. They feel weighted. They sound right when driving the right drivers.
Yeah mostly empty space because of highly integrated circiuts. However, even higher powered audio amp chipsets should be a little more substantial just to handle the power passing through through and probably heat sinks to dissipate heat energy that doesn't come out as sound energy.
I recently bought a tuner and true to form I had to have a look. Turns out there's just a fat chip on the little front panel PCB, a few tact switches, an LCD AND NOTHING ELSE! So where's the tuner? It's all in software and the entire chassis is empty save for a tiny little SMPS at the rear by the massive AC inlet. And it works great as tuners go. Why have rows of LC stuff when you don't have to?
That's a funny question Paul
Heck, I was going to blame it on surface mount. But matching up to a standard width works too.
Funny you mention the air / empty space. I have a Phase Linear 400 and even with the reduced depth as compared to a Pioneer Spec series, there's more empty real estate inside than the Pioneer. That Spec amp is chock full to the brim. BTW, they both pass the KK test and the weight test. As one friend said, these things are like a window AC unit with handles.... and a power cord to match.
Stetson amps are small it's good to hide the amp in the car instead of mounting on the subwoofer box
Seem like new generation don't have need for high quality sound! In the 80's most young people know brand for good high quality sound and we save money to buy it. Today they just listen to phone speaker or headphones. I think they missing a lot.
I think many amplifiers are empty inside because they don’t have a good father figure in their lives.
If there is room inside, better for heat dissipation.
Wasn't there also that old classic theory of trying to reduce the number of parts or components to try and reduce any artifice or sonic interference in the signal path too?
It is actually in reverse. You will still find the better and more expensive hardware bragging about discrete components instead of ICs. Thermal noise crosstalk when multiple devices are on one silicon! Point to point wiring over circuit boards. Less capacitance and path crosstalk....
are you telling Paul or the community? this guy don't even put tone control in his product. short distance purest sound.
I have an 80's metron 300 watts per channel branded cerwin vega. Its full of stuff and knock knock pass and it weights close to 60 pounds.
Another reason for space is that electrical components got smaller and more powerful. Think back to the Crown DC 300. Large E-frame transformer, large low-density capacitors, TO3 transistors, etc. Transformers are (for the most part) smaller toroidal transformer, Higher density caps, (switch-mode supply in some lower grade amps) TO3P or TO220 transistors, etc.
I still love my Adcom GFA-555's.....
Really awesome amp right there very nice Paul. I have a Nakamichi PA-7, What? lol. Yes they are, becoming smaller because a lot are implementing switcher amps with caps instead of transistors and massive transformers. Less heat, no noise and the winning part: cheap to make. Though I’ll take my transformers and noise any day over a class ‘D’ switcher. Just not a true ‘amp’, no soul and ‘sim’ sounding. Great video, long live two channel.
Was just reading about the PA-7, that's a nice amp right there. Nelson pass design. How's it sound?
@@peterlarkin762 Hey Peter, outstanding for its age. Very dynamic amp, (some have said ‘veiled’, but that’s just slander imo and using Audioquest Evergreen for signal) love the older stuff that’s built like real equipment. Nice to have something Mr. Pass worked on, what a talent. It was part of Nakamichis flagship line back in 1988, a good friend here in Daytona that owns ‘Stereo Types’ was upgrading in 2000, and wanted 3k for the amp, pre and tuner. I gave him the “So is that the price for your FRIEND” line, and he looks at me and says: “Go get me 2k cash before I change my mind” with a smile lol. Not a bad day at all at that point, pretty righteous for a decent system. Thanks for your interest Peter, enjoy sir.
Thanks Randy, man! Think it's an amp on my 'see it, buy it' list now. Honestly, discrete power amp circuitry has not evolved a huge amount since that was produced. And it's such a beautiful chassis.
Rare here in Ireland. A PA5 would suffice. You got a seriously good deal for the stack!
I've also been researching the amazing Nakamichi Dragon CT turntable and it's self centering mechanism. Ingenious.
Best wishes and peace.
Peter.
@@peterlarkin762 th-cam.com/video/dVbAoFfjUtQ/w-d-xo.html just finished this.
How many Class D have you heard??
I've been listening to amps for years (35 +) class A class A/B as that was all that was available
I'm currently using a tube preamp with a class D power amp (600 wpc).
It utterly destroys any of the traditional Amps I've had ( creek, Arcam naim Denon etc etc)
I'll never buy another class A classA/B.
Why do I feel like this ? Why does this combo sound so superior to anything else I've ever owned??
Reusing the same chassis for multiple models.
👍 Even though he did not mention class D amp, we can imagine the class D amp in the standard chassis looks so "empty". Chinese manufacturers make very compact class D amplifiers like SA-98E ignoring the standard 17"(430mm) width, with an external AC/DC adapter.
😂GOOD STORY PAUL 🤗😍😍😍
It's the representation of audiophiles. There's lots of stuff to entice you to spend money on things, but not as much as you think on the inside XD
I use compact electronics, but still use big speakers lol
Topping and others are turning this 17" thing on its head... Can fit separates from Topping (DAC , Preamp and Amp) all inside of a 17" 2U case with arguably better specs
The last Topping amp I bought sounded worse than the Dayton Audio amp that used the same chip. It didn't sound too bad, but not worth the extra $ over the cheaper one. More of a complement to the parts express folks than anything else I guess. I think both models are now discontinued.
Strange that this guy didn't even mention airflow as one of the reasons.
Also (with some) the lack of space being the main reason for amp destruction! 😂
so they feel more premium. apart from the rack angle. these two aren't particularly empty though so not that good examples.
that's a nice toroidal.
Once I looked inside a musical fidelity amp, and that one had a transformer in one corner, a green circuit board in another and the rest was just air and heatsink on the outer edges.
The knock knock test really made me laugh…..i am also from singapore & i recall in the 70s & 80s, many ignorant audiophiles back then judge an amplifier by its weight. The heavier they weigh, the better. I fondly remember how a group of older audiophiles went totally nuts when my puny 3.5kg Creek 4140 integrated amp massacred a humongous 50kg pioneer receiver in terms of bass control, dynamics & sound quality. They couldn’t believe what they heard. Scratched their heads real hard. 2 days later i repeated the same trick with another puny amp in the form of Mission Cyrus 2. Today i own LFD LE 3 which is also puny & has plenty of underutilised real estate inside. But i far prefer its sound to many 30 to 50kg behemoths. Pick your poison!
My current power amp ( class D ) is 600 wpc and weighs 5kg !!!! Utterly destroyed the 25kg Arcam. The future is lighter 😁😁!!!
A lot of old Amps need a lot of cooling special the first class a/b Amps.
The big weight come from cooling heatplate and the travo ring .
After a/b with Mosfet the amp las weight and cooling need IT.
Later airflow by a fan and again lower weight .
After dat class-d amp what do not really need a lot of cooling.
Its how a/b VS d amp works.
A/b Amps have always power on the speaker.
A class-d and somtimes digital d amp .
Can set the power of to your speakers.
No sound means no Heat .
Than real old class a Amps.
Well that have to Heat u for a good sound.
Its Just what the type amp it is.
Point to point wiring is the best.
Standard sizes of cases started to get too big for standard components due to miniaturisation. When I purchased my first stereo set in the 80s, it was the standard 19“ size. The rack had to be that wide because of the vinyl record player on top of it. But then CDs were about to take over, and there wasn’t any need for big cases any longer. So Sony decided to produce smaller sets. But they still had to provide stereo sets of the ‚classic' size. What did they do? Produce the smaller form factor PCBs, mount them into the big cases and leave half the case empty.
You would think that by adding space in between components. That it would help reduce crosstalk. If thats the word im looking for. One reason why separates and external power supplies can have lower noise floor. Some people may call it fog.
Then have a look at some B&O stuff, - they are the true masters of having as much as possible in as little as possible !
Does anyone know if those caps are Elna Silmic ii? They seem to be the same color
Gotta 77 Fender Quad Reverb ,
Heavy Solid Amplifier .
Passes the knock knock test ;)
What a great guy, i bet a brilliant employer with a happy team ….
I love these little stories you give. I'm sure you'd run a little sideline doing public speaking.
Check out his audiobook... it's a good listen.
@@FOH3663 Do you have a link? Or is in on his TH-cam?
@@TheGramophoneGirl
99% true
Loved the story of the Knock Knock Test ✊✊
Why am _I_ so empty inside? Can you answer that, Paul? ;_;
Thank you. Hong Kong WAS a nice place. Definitely. But not any more. Most Hong Kong people are still nice though.
Knock! Knock!
Who's there?
Candice.
Candice who?
Candice door open, or am I stuck out here? ( You asked for it )
Coming from the semiconductor field, electronics have become more efficient, and therefore smaller, while keeping the shell the same, so over the years its gonna get worse. I remember back in 1986 while stationed in NY i bought my first CD radio built by JVC, it was ~$100 with detachable speakers, and "chock full of parts, It was a solid Japanese radio, some one else bought a Koss or something like it but it was Chinese. When he opened his up and found a few electronic boards with metal plates giving the false impression of a quality radio, but was junk that caused more interference than it was worth.