I worked in studios with Bryston 4B amps and green was on / blinking green was signal present / yellow high input signal / red was either overloaded input signal or overheated amp. Great sounding amps. I never experienced one that showed red as they are very well built.
That's what I suspect because my crest which is almost the same as far as a design goes as this has Blinky lights when there's signal they're not on when there's no signal because it has separate power lights that are always on but green lights blink when signal and if you overload a clip they go red. The Crest is pretty much impossible to overheat because it has a dual speed fan that if the output power is high or the temperature is high the thing sounds like a jet engine it fires so much air over that heat sink it's not going to overheat. the guy that owns this one no insists that they're not supposed to blink because apparently he has another one that they don't blink on.
@@12voltvids Could be a latter production run PCB that had changes done. I have a couple of Adcom 545 mk II amps that have extra electrolytic caps on the driver boards that are not on the schematic or parts list. I could not find any service bulletin as to the changes, but one must exist.
Hello. I moved some gear around last night and today the right channel on my Bryston appears to be dead. I’ve done basic troubleshooting but I don’t know much about this type of equipment so I can’t diagnose on my own. What could this be?
Interesting to see the internal layout, I have a Numark Dimension 4, it has 2x 2 speed fans cooling the heatsinks, I am surprised the Bryston is passively cooled. Those power transformers look impressive, I was expecting toroid tx's.
My crest has a massive transformer and a big 2 speed ac operated fan. Power switch is a 15 amp circuit breaker on the front not a cheesy little power switch as on this one.
@Kent Teffeteller agreed but then hey I'm just waving my patriotic Canadian flag. But yeah they do make good products as to our friends South of the border.
I have 12 vs900 and 8 v900. Damping factor is 1000 on the crest and 500 on the brystons. This means the crest v series is superior at tight bass control on large cone speakers (15's, 18's, 21's) vs the bryston.
4:35 That's true for US/Canada - not for Europe. Adding freight costs, import duties, taxes and given their rarity and reputation, I'd say easily over a couple of grand or more over here.
Aww. I was a manager at a cinema for a while and we used these amps for the Dolby SRD system...very reliable compared to the Crowns and EV amps that seemed to fail often and we would have to refund peoples tickets etc
Now i really regret not staying in NZ during my travels. Best country ever. The scenery and people are great, but now Robertson screws too? You really have it all:)
What's the power consumption? Is power consumption more than the output? I bought a stereo system that claimed "700 watts RMS" but only draws 80 watts. I think that's ridiculous. I assumed you cannot get more power out than what you put into it.
It's drawing 80w AC on the mains ... And outputting 700w RMS into 8ohms at say for e.g, 30v ac at clipping. Basically these power draw vs. Output ratings are not comparible because the output is subject to the efficiency of the amp (how much power ends up as heat) and impedance of the load. Your amp would use maybe 1.4 amperes from the mains supply which is maybe a digital or switching or high efficiency class B design. Valve power amps are inefficient, so they consume a lot from the mains and will output way less power.
@Douglas Blake according to the manual this one draws 100 Watts just sitting idle with no sound. I'm sure my big Crest audio does about the same, just to keep the capacitors charged and the idle current going through both channels to keep all the transistors biased to the point where they're not in cut off. By comparison my little tube amplifier which only outputs 50 watts per channel idles at 300 watts at all times, my other little tube amplifier that I built which is the class A and only puts out 9 watts per channel draws a whopping 200 Watts just sitting there doing nothing and it only has four tubes on it. there's so much power waste on a tube amplifier it isn't funny but hey in the winter it helps heat your house. My tube amp isn't even connected at this point it just sits on the shelf for show someday I might connect it up again and listen to it but right now I'm having too much fun listening to this big 900 watt Crest audio that I picked up for under $200. I paid more for the preamp believe it or not then the power amp.
@Douglas Blake my electric meter doesn't need any help spinning. I liked my old one much better. A few well placed super magents stopped that disk spinning in it's tracks under low load. Was well concealed in the wood box that was built around the meter with just the front of the meter poking through to be read. When the announcement came that smart meters were coming I knew the days of a bigger bill was coming. Did s pretty good job too. Unless something like water heater or dryer was running that dam disk was completely still. The good old days.
POWER UP SEQUENCE After pushing the power switch, each channel LED will turn from unlit to red (mute). When the power supplies have stabilized, the channel will come out of mute and the LED will change to green (normal operation).
Lights are supposed to stay Greeen. They will flash Yellow approching clipping. Red is soild clipping. That means lower the volume. A few hundred bucks? That amplifier is about 35 years old. People are asking almost $800.00 USD for ones like that. That amp was rated at 200 Watts x 2. It's much better than any Crest.
Actually they are not. There were different led boards on the different revisions. Some have multi colored LEDs and others just single colored. This one the lights are solid when on and no signal and start blinking as soon as there is signal present. The reason is this amplifiers designed to be installed in a cabinet remotely from speakers in a theatre or club where there are multiple amplifiers. The flashing green let's the operator know that the amp is working. My crest is the same. Solid green on power flashing green when signal flashing red at pre clip and solid red when clipping is detected. My crest has another feature however which is great. As you get to the pre clip level and the light starts blinking the limiter / attenuator kicks in when it is solid red the attenuator is active reducing the output to eliminate the clipping which at the power it puts out 450 per channel onto 4 ohms would destroy your speakers in a flash. To it's pretty much impossible to clip as it only goes to the limit and then no louder no matter how hard you drive it. All amps should have been designed this way IMHO.
@@12voltvids There are two extra circuit boards attached to the back side of the front panel that hold the LED's.. These are the optional sig on circuits that are not installed in the regular 4B's of that era. You could try disconnecting the red power wire that connects to these boards. That might disable it?
Lots of screws. Lol. How many uf are those filtering caps?? That’s kind of a beast. My 1985 Onkyo sounds fantastic, it’s only 65 watts per channel and it’s more than my 3500 sq. Ft. House and neighbors can handle. $50.00 from the original owner on Craigslist.
@@fghjfghgj - I should have properly elaborated. It was 2am. I was referring to the fact that this Bryston amp has way more power than I need for my relatively large house. I guarantee you my Onkyo receiver has lower THD as well. My father is a brilliant retired mechanic. He specialized in Porsche, VW & Volvo. Fu*%k you very much for comparing the worse German cars ever made to my fantastic Japanese golden era receiver. My Onkyo is an Air cooled 911. Btw. Ferrari is nothing to brag about, some of the most unreliable cars in history!
@@12voltvids Bullsh*t with respect brother. I can buy a Crest Audio VS900 right now for less than $200.00. It’s a monster power amplifier and I’m sure it sounds good but no way in hell does it sound better than my Onkyo TX-65 receiver even before I upgraded the power supply. I’ll take the Pepsi challenge and bet you the money you lost on that eBay camera deal that in a blind listening test at least 7 out of ten audio enthusiasts would choose the sound quality of my Onkyo TX-65 over your Crest Audio! Your Crest Audio monster has almost four times more Total Harmonic Distortion! God bless dude.
@@ryanjofre actually it doesn't. At full rated power sure but at normal listening levels it is more like 0.01. Ear can not perceive distortion below 0.12% so that is a moot point. And I have had many listen to my system and comment on how good the sound stage it. That's what it is all about, sound stage. Just because i have 250 watts per channel doesnt mean it is being used. Average power when listening is perhaps 10 to 15. Lots of headroom. With commercial hear the thd rating is maximum at full power just before the amplifier clips. They sweep the frequency response at full power and find the highest distortion at full power. Consumer gear on the other hand they rate it at typically 1 or 2 watts power so they can publish low numbers. Pro gear is also extremely low in the thd and imd at those low power level. Why do they measure at max power? Because is a club or theatre or on stage the amp it being driven to extremes typically into very low loads. Try driving your amp into 2 ohm loads and see what happens. Lol.
Great looking Amplifier.. I suspect the guy thought it was a clipping warning and was afraid he would be doing damage by running it. All he had to do is use his ears an he would know !
He bought 2 amplifiers from a theater that closed down and one of his other one doesn't blink. However it also goes red where is this one doesn't. I've tried explaining to him that Bryson has several different versions of the four B and the other one that he has is probably a different revision but he's not buying that. He wants to bring his other one over for me today so that I can open it up and see if it's the same inside I'm sure once I do will find it completely different layout and the other one and then I can show it to him and show them why it's behaving differently. Again it's an audio file and we all know how brilliant some audio files are with the stupid amount of money that they spend on some of the stuff. I worked with a guy who got fired but that's beside the point who was an audio file and he would argue until you were blue in the face that his $5,000 oxygen-free directional cables could only run one way if you turn them around the other way they wouldn't sound proper and he would argue until you were blue in the face you couldn't argue with the man because he spent all this money on cables and connectors and equipment.
Better if it only had speaker protection, had a couple of 3B amps in the past for repair with shorted output transistors, customers also had their woofers burnt out, don’t like these kind of amps for that because people with such amp usually have expensive speakers also…. Thats why I prefer tube amps with output transformers, no risk of dc on the speakers.
Very true never blown speakers with vacuum tube amps. Even driven into full distortion isn't going to hurt them because of that nice output transformer that's going to remove the flat top and round everything off so the speaker can handle it plus they sound cool when they distort
There are different versions of this amp. I haven't found any official documentation as to what this indicates. Considering that it's a dual mono design with two separate power transformers two separate rectifiers and two separate sets of capacitors it would be expected that if there was a problem on one of the amplifiers it would only show up on one channel and that both of them would not blink if that was an indicator that there was a problem. because the chances of having an identical failure causing an identical fault indicator for two separate model amplifiers at the same time it's kind of strange. Not saying it couldn't happen just saying it be not expected to have both channels going to a fault at the same time. I'm sure these indicators are powered directly from the amplifier board itself as well. Again I don't know anything about how the indicators operate on this unit, I have a Crest audio and on mine it has a power light and then it has two activity indicators when there's no sound the activity indicators are out as soon as you give it any type of input they start to flash just like these ones and they will remain flashing if you get into an overload condition there's a second light which is red which comes on or if there's a fault the red light comes on.
Monster amp! I haven't ever seen one of these in the US. Too bad. Thanks for the demo with a view under the hood.
I worked in studios with Bryston 4B amps and green was on / blinking green was signal present / yellow high input signal / red was either overloaded input signal or overheated amp. Great sounding amps. I never experienced one that showed red as they are very well built.
That's what I suspect because my crest which is almost the same as far as a design goes as this has Blinky lights when there's signal they're not on when there's no signal because it has separate power lights that are always on but green lights blink when signal and if you overload a clip they go red. The Crest is pretty much impossible to overheat because it has a dual speed fan that if the output power is high or the temperature is high the thing sounds like a jet engine it fires so much air over that heat sink it's not going to overheat. the guy that owns this one no insists that they're not supposed to blink because apparently he has another one that they don't blink on.
@@12voltvids Could be a latter production run PCB that had changes done. I have a couple of Adcom 545 mk II amps that have extra electrolytic caps on the driver boards that are not on the schematic or parts list. I could not find any service bulletin as to the changes, but one must exist.
at least you got a video out of it and review it.
Lights are flickering due to the indication of the audio signal, which is normal!, great video, Dave
I have an earlier one and the LED stay solid green. I had an issue with an edge connector causing mine to shut off one channel.
Picked up a parasound a21 for a really reasonable price. Believe close specs to this amp but the parasound is very beefy.
Very very nice amp
I have a Bryston 2B LP Pro amplifier, as the other people say green LED for power ON and Turns red for audio clipping.
This is an extremely good amp! Goof!
that blinking is a deal breaker for me...
Hello. I moved some gear around last night and today the right channel on my Bryston appears to be dead. I’ve done basic troubleshooting but I don’t know much about this type of equipment so I can’t diagnose on my own. What could this be?
Interesting to see the internal layout, I have a Numark Dimension 4, it has 2x 2 speed fans cooling the heatsinks, I am surprised the Bryston is passively cooled.
Those power transformers look impressive, I was expecting toroid tx's.
My crest has a massive transformer and a big 2 speed ac operated fan.
Power switch is a 15 amp circuit breaker on the front not a cheesy little power switch as on this one.
@Kent Teffeteller agreed they're one of the best that you can get. And yes I am waving my patriotic Canadian flag here.
@@12voltvids I have a denon power amp got it in 2005 works great no issues dooesnt break down. Keeps runing no buzzing.
@Kent Teffeteller agreed but then hey I'm just waving my patriotic Canadian flag. But yeah they do make good products as to our friends South of the border.
I have 12 vs900 and 8 v900. Damping factor is 1000 on the crest and 500 on the brystons. This means the crest v series is superior at tight bass control on large cone speakers (15's, 18's, 21's) vs the bryston.
Correct
According to the owners manual, those are clipping indicators.
What a beast!, take all those crappy screws out and put pozidrive ones in ....... Joking dave :-D.
4:35 That's true for US/Canada - not for Europe. Adding freight costs, import duties, taxes and given their rarity and reputation, I'd say easily over a couple of grand or more over here.
Aww. I was a manager at a cinema for a while and we used these amps for the Dolby SRD system...very reliable compared to the Crowns and EV amps that seemed to fail often and we would have to refund peoples tickets etc
They were 3 or 6 per rack depending on the size of the auditorium
Here in new zealand the council contractors also use Robertson screws
Now i really regret not staying in NZ during my travels. Best country ever. The scenery and people are great, but now Robertson screws too? You really have it all:)
@@peterlarkin762 except decent trains the rail track is so narrow that's travel is slow
250 watts VS 500 Watts is only 3db louder...
Q: How much is twice as loud? (twice the volume) for 100Watts? A:( 1Kw) approx.
Looks like an old English Exposure IV dual rugulated.
I have 2 of them and they do flash under operation, left side led signal in detect, right side led signal out detect.
I know how they work. The led drive board was nicely roasted which was repaired. It's the owner that was misinformed in the operation.
Robertson are the most difficult to strip, provided the socket and driver tip are matched. Flatheads I hate, driver always slipping out of the slot.
What's the power consumption?
Is power consumption more than the output? I bought a stereo system that claimed "700 watts RMS" but only draws 80 watts. I think that's ridiculous. I assumed you cannot get more power out than what you put into it.
It's lots. 1500 watts just like my crest.
It's drawing 80w AC on the mains ... And outputting 700w RMS into 8ohms at say for e.g, 30v ac at clipping. Basically these power draw vs. Output ratings are not comparible because the output is subject to the efficiency of the amp (how much power ends up as heat) and impedance of the load. Your amp would use maybe 1.4 amperes from the mains supply which is maybe a digital or switching or high efficiency class B design. Valve power amps are inefficient, so they consume a lot from the mains and will output way less power.
@Douglas Blake according to the manual this one draws 100 Watts just sitting idle with no sound. I'm sure my big Crest audio does about the same, just to keep the capacitors charged and the idle current going through both channels to keep all the transistors biased to the point where they're not in cut off. By comparison my little tube amplifier which only outputs 50 watts per channel idles at 300 watts at all times, my other little tube amplifier that I built which is the class A and only puts out 9 watts per channel draws a whopping 200 Watts just sitting there doing nothing and it only has four tubes on it. there's so much power waste on a tube amplifier it isn't funny but hey in the winter it helps heat your house. My tube amp isn't even connected at this point it just sits on the shelf for show someday I might connect it up again and listen to it but right now I'm having too much fun listening to this big 900 watt Crest audio that I picked up for under $200. I paid more for the preamp believe it or not then the power amp.
@Douglas Blake my electric meter doesn't need any help spinning. I liked my old one much better. A few well placed super magents stopped that disk spinning in it's tracks under low load. Was well concealed in the wood box that was built around the meter with just the front of the meter poking through to be read. When the announcement came that smart meters were coming I knew the days of a bigger bill was coming.
Did s pretty good job too. Unless something like water heater or dryer was running that dam disk was completely still. The good old days.
POWER UP SEQUENCE
After pushing the power switch, each channel
LED will turn from unlit to red (mute). When the
power supplies have stabilized, the channel will
come out of mute and the LED will change to
green (normal operation).
Lights are supposed to stay Greeen. They will flash Yellow approching clipping. Red is soild clipping. That means lower the volume.
A few hundred bucks? That amplifier is about 35 years old. People are asking almost $800.00 USD for ones like that. That amp was rated at 200 Watts x 2. It's much better than any Crest.
Actually they are not. There were different led boards on the different revisions. Some have multi colored LEDs and others just single colored. This one the lights are solid when on and no signal and start blinking as soon as there is signal present. The reason is this amplifiers designed to be installed in a cabinet remotely from speakers in a theatre or club where there are multiple amplifiers. The flashing green let's the operator know that the amp is working.
My crest is the same. Solid green on power flashing green when signal flashing red at pre clip and solid red when clipping is detected. My crest has another feature however which is great. As you get to the pre clip level and the light starts blinking the limiter / attenuator kicks in when it is solid red the attenuator is active reducing the output to eliminate the clipping which at the power it puts out 450 per channel onto 4 ohms would destroy your speakers in a flash. To it's pretty much impossible to clip as it only goes to the limit and then no louder no matter how hard you drive it. All amps should have been designed this way IMHO.
Normal. That late 80's vintage 4B has the optional sig on feature where the green Leds flash when signal is present.
Owner is insistant than it is not. So i guess I need to figure out how to stop them from blinking.
@@12voltvids There are two extra circuit boards attached to the back side of the front panel that hold the LED's.. These are the optional sig on circuits that are not installed in the regular 4B's of that era. You could try disconnecting the red power wire that connects to these boards. That might disable it?
Old school brute.
It's got balls alright.
Lots of screws. Lol. How many uf are those filtering caps?? That’s kind of a beast.
My 1985 Onkyo sounds fantastic, it’s only 65 watts per channel and it’s more than my 3500 sq. Ft. House and neighbors can handle. $50.00 from the original owner on Craigslist.
Not even in the same league. When I put my Crest Audio VS900 in service I dam near pissed my pants the sound was so good, and loud!
you are compering a trabant to a ferrari
@@fghjfghgj - I should have properly elaborated. It was 2am. I was referring to the fact that this Bryston amp has way more power than I need for my relatively large house. I guarantee you my Onkyo receiver has lower THD as well.
My father is a brilliant retired mechanic. He specialized in Porsche, VW & Volvo.
Fu*%k you very much for comparing the worse German cars ever made to my fantastic Japanese golden era receiver. My Onkyo is an Air cooled 911.
Btw. Ferrari is nothing to brag about, some of the most unreliable cars in history!
@@12voltvids Bullsh*t with respect brother. I can buy a Crest Audio VS900 right now for less than $200.00. It’s a monster power amplifier and I’m sure it sounds good but no way in hell does it sound better than my Onkyo TX-65 receiver even before I upgraded the power supply.
I’ll take the Pepsi challenge and bet you the money you lost on that eBay camera deal that in a blind listening test at least 7 out of ten audio enthusiasts would choose the sound quality of my Onkyo TX-65 over your Crest Audio!
Your Crest Audio monster has almost four times more Total Harmonic Distortion!
God bless dude.
@@ryanjofre actually it doesn't. At full rated power sure but at normal listening levels it is more like 0.01.
Ear can not perceive distortion below 0.12% so that is a moot point. And I have had many listen to my system and comment on how good the sound stage it. That's what it is all about, sound stage.
Just because i have 250 watts per channel doesnt mean it is being used. Average power when listening is perhaps 10 to 15. Lots of headroom.
With commercial hear the thd rating is maximum at full power just before the amplifier clips. They sweep the frequency response at full power and find the highest distortion at full power. Consumer gear on the other hand they rate it at typically 1 or 2 watts power so they can publish low numbers. Pro gear is also extremely low in the thd and imd at those low power level. Why do they measure at max power? Because is a club or theatre or on stage the amp it being driven to extremes typically into very low loads. Try driving your amp into 2 ohm loads and see what happens. Lol.
Great looking Amplifier..
I suspect the guy thought it was a clipping warning and was afraid he would be doing damage by running it.
All he had to do is use his ears an he would know !
He bought 2 amplifiers from a theater that closed down and one of his other one doesn't blink. However it also goes red where is this one doesn't. I've tried explaining to him that Bryson has several different versions of the four B and the other one that he has is probably a different revision but he's not buying that. He wants to bring his other one over for me today so that I can open it up and see if it's the same inside I'm sure once I do will find it completely different layout and the other one and then I can show it to him and show them why it's behaving differently. Again it's an audio file and we all know how brilliant some audio files are with the stupid amount of money that they spend on some of the stuff. I worked with a guy who got fired but that's beside the point who was an audio file and he would argue until you were blue in the face that his $5,000 oxygen-free directional cables could only run one way if you turn them around the other way they wouldn't sound proper and he would argue until you were blue in the face you couldn't argue with the man because he spent all this money on cables and connectors and equipment.
@@12voltvids lol
Airline safety-video music :)
Mmm Robertson screws. You lucky 'nadians.
Any $200 dollar Brystons, send em my way. Going price for a nice 4B is around a grand here in Vancouver
The guy that got these 6 paid 300 each.
Better if it only had speaker protection, had a couple of 3B amps in the past for repair with shorted output transistors, customers also had their woofers burnt out, don’t like these kind of amps for that because people with such amp usually have expensive speakers also….
Thats why I prefer tube amps with output transformers, no risk of dc on the speakers.
Very true never blown speakers with vacuum tube amps. Even driven into full distortion isn't going to hurt them because of that nice output transformer that's going to remove the flat top and round everything off so the speaker can handle it plus they sound cool when they distort
My 4b lights don't flash.
3 different design.
They'll start flashing red when it starts clipping.
Not normal.
There are different versions of this amp. I haven't found any official documentation as to what this indicates. Considering that it's a dual mono design with two separate power transformers two separate rectifiers and two separate sets of capacitors it would be expected that if there was a problem on one of the amplifiers it would only show up on one channel and that both of them would not blink if that was an indicator that there was a problem. because the chances of having an identical failure causing an identical fault indicator for two separate model amplifiers at the same time it's kind of strange. Not saying it couldn't happen just saying it be not expected to have both channels going to a fault at the same time. I'm sure these indicators are powered directly from the amplifier board itself as well. Again I don't know anything about how the indicators operate on this unit, I have a Crest audio and on mine it has a power light and then it has two activity indicators when there's no sound the activity indicators are out as soon as you give it any type of input they start to flash just like these ones and they will remain flashing if you get into an overload condition there's a second light which is red which comes on or if there's a fault the red light comes on.
Tell him to remove the lights game over. Do you want to listen to it or look at it .
No he just thinks it the lights flashing indicate that there's a fault that's all.