I just recently bought an SMSL SA-300 for my bedroom. Has a line-level input as well as Bluetooth 5.0 and USB DAC (connected to a computer) for my bedroom. Seems SMSL really is on a mission to build good quality stuff. My little SA-300 drives a pair of Phase Technology 2.5 bookshelf speakers quite handily. The sound quality from all sources is quite impressive! The sound your camera recorded is far better than average. I can tell that unit has a nice clean sound to it.
Nice review. I like the display and the compact size although the tiny letters would be difficult to see without reading glasses. The other two shortcomings are the limited capacity to accept files and the lack of Bluetooth. Thanks for sharing!
Cat3 cable is actually fine for amps / speakers tbh. There was (and probably still is) a "fad" on certain audio forums where people made speaker cables by braiding a few lengths of Cat5 together. It's supposed to result in quite low inductance etc., but that's definitely verging on "audiophool" territory. lol (I used some braided Cat5 on my own front speakers for a few years, but normal copper speaker cables are cheap enough now to not go to that effort.) Some people put way too much emphasis on speaker cables tbh. Granted, if you're lucky enough to afford speakers costing $5,000 or more, then you'll want better cables too, but for most people, a simple stranded copper cable with a decent cross-section (for higher current) will be fine. Anything much more expensive is usually overkill for most home (and even home theatre) use. Obviously it's a different requirement in very large rooms / theaters / studios / stadiums, but that usually just means thicker more robust cables with expensive Neutrik connectors etc.
What interests me about this unit is the optical input. Ive been looking for a small, inexpensive amplifier that has optical, for powering vintage hifi speakers on a PC.
I see it says in the manual it can handle 4ohm speakers, but what about 8ohm speakers, it is a very nice unit. This would make a great amp for my Chromecast Audio.
Works fine into 8 ohms, Rated power will be a little less as an 8 ohm speaker isn't going to draw as much current. The speakers I tested it on are 8 ohm speakers, and you hear the sound quality. It sounded great, and puts out enough volume to generate a noise complaint.
It is a very smart and compact device, very nice :-D The insides do look clean and well designed, nothing naughty or nasty. For me, i would want a button for the menu select, not a shared rotary/button, but that's just my taste, and yes the display could have been bigger. Failures would be the switchmode brick, it will be an unknown special, they go poof lol.
that lp i i know there is no way i could get a copy of that but iam a Hammond B3 Jazz organ player would like to know the tune Dave and have you buy any chance have This to a PC Clean up progam to take out all the pops
Looking at the front panel it looks like it has capability of IR control. I just saw you mentioned remote so if it's an actual IR remote that's pretty cool. I would love to see that tube amp! And I'd like to see a teardown of the unit.
Yes it comes with an IR remote. I would love to see that tube amp too, as I have 3 modern tube amps now, 2 which I built, and I also have a vintage McIntosh MAC1500 which I will rebuild one of these days.
I've had this amp for a year or two now, and it's been fine for it's purpose (2 bookshelf speakers) but a few weeks ago I noticed the display brightness was very, very low. To the point where I couldn't see it in sunlight, you can only see it when it's dark and even you need to get close to it to see. I've looked through the settings and there's nothing for brightness, only the timeout options. I've searched online and haven't found anything. Any suggestions? Seems silly to replace it just because the display is slowly failing - everything else works as it should.
Its an OLED display. They do get dim. My phone screen is getting dim now too. The oled on my car charger is the same. They are all based on phosphor and it wears our.
They are much more efficient than A/B designs, and have very low distortion figures. Most people wouldn't be able to tell the difference in blind listening tests. Sure the hard core believers will try to sway your opinion, just like they try to convince everyone that vinyl is better than full digital, or that #2 gauge speaker wire, and 1000.00 interconnect wires is going to make a difference in sound, but put them in a room with 2 speakers, and not tell them which amplifier was driving those speakers and they won't be able to pick a winner. Now this is not true when comparing to tube gear, and the tube gear will generally win. Not because they are better, in fact no tube amp can even come close to a solid state amp as far as dynamics or distortion levels, but tubes add their own colorization to music that makes them sound pleasing and less sterile which many people favor, and will pick the tube amp every time as sounding better. I tend to agree, a class A tube amp is hard to beat for a musical sound, even though it has much more distortion and the frequency response more resembles a camels back than a ruler.
Yes it is a hybrid plug. You can put in a standard stereo 3.5mm, and it also has a toslink input in the base of the plug. A toslink 3.5mm adapter is used. It looks like a regular 3.5mm plug but it is plastic and has the optical fiber inside it. You can't have both at the same time, it is either analog copper, or digital optical.
It does have a DAC, but many times they refer to class D as digital because of the way the outputs work. The output is a square wave which can be represented as 1's and 0's! Yes the output is digital, there are only 2 states on and off. 1 and 0. The analog signal is convered into a PWM, pulse with moulation signal, which is represented as a 1 or 0 with the duty cycle changing to follow the analog input much like FM radio. FM radio the frequency changes to follow the audio signal, PWM the frequency remains constant, just the duty cycle changes. The audio signal is still represented as a digital signal it is just not encoded into anything such as PCM or pulse code modulation. The analog signal is represented by an ON - OFF digital carrier, which when the carrier is stripped reveals the original analog signal, amplified.
@@12voltvids So if I plug in a cd player to its aux in, does it bypass the dac built in the amp or not? I like my cd player to use its dac when connected to the smsl.
Somebody wasn't listening at the beginning when I went over the specs. Yes it supports .WAV and .FLAC from both SD card and USB stick. at the 1:55 point is where I WAV and 2:20 for flac.
Hello, After seeing the your review about this amplifier, i purchased one from amazon. For starters i had problem with the adapter they send with it, i plugged the adapter the light came on the amplifier and stopped instantaneosly, but i had a different adapter voltage was 18V and current about 2Amps it was bit less than the original spec but the amp works they are going to refund for the adapter. But my question is i for some reason placed the meter across the speaker output terminals there was a voltage of 20mV, and with respect to adapter negative terminal and positive speaker output terminal it was measuring about 9volts, is that normal or something wrong with it? Hope to hear from you soon, Thank you and Regards.
These amplifiers use a BTL, or Bridge Tied Load output, so you don't measure between the ground and speaker terminals. You will see a voltage. If you measure between the speaker terminals with a load across the speaker terminals you will see nothing. How they operate is they generate a PWM switching signal, with the + and - outputs running out of phase with each other. The output MOSFET switch rail to rail so 0 to full B+, be it 18 or 19 volts. They will operate on pretty much anything up to the max rating of the chip. What comes out is a square wave at a very high frequency. Usually around 400KHz As the audio goes positive, the duty cycle increases on the + amplifier, and decreases on the negative amplifier. As the waveform goes to the negative phase, the positive side duty cycle decreases, and the negative side increases. The amount of swing that the PWM signal makes from its resting frequency determines the loudness. If this sound like how FM radio works, well it is very similar. In an FM transmission the duty cycle remains 50/50 and the frequency changes to follow the audio signal. In Phase modulation, the carrier phase changes. Clip a phase modulated sinewave and it starts to look much like a PWM signal, except that in PWM, the switching point is a hard switch, not a sightly sloped angle as a phase modulated carrier would be, but they look similar. This PWM signal is passed through the choke coils and capacitors in the output where the high level rail to rail carrier is removed, and you are left with a very clean signal, and it is clean. Almost too clean for my liking. I have listened to this little unit quite extensively over the past week, and it does sound very nice, but a bit sterile. I go back to my tube amp on the same speakers, and the music has more body, a fuller more alive sound. Even though any solid state amp will destroy tube amps on paper, and when measured with test equipment. The tube amplifier, with it's high even order harmonic content just adds a warmth that you have to experience to understand. There is a reason that some people will pay as much for an amplifier as a brand new car. Sometimes you just can't beat the old school tech.
Hello sir, thank you for your reply, when I measure under load conditions across the speaker terminals I get about 20mV is this is dc-offset? Or will it be okay?
don't be embarrassed about what wire you use. I use radioshack lamp light power wire for my front 2 towers powered with Kenwood km-106 125-150w rms@8ohm per channel and thick power extension cable 2 wire + & - no ground for my 4 passive subwoofers powered with 2 Kenwood Basic M2 220w rms@8ohm also using a 2x4 MiniDSP for entire system adjustments.
Hi, is it possible to connect headphones to the device in any way?, It occurs to me if this is possible. ¿Can a standard 3.5mm stereo headset cable be used in the rear optical input to use it to listen to the headphones? Thank you very much for your time! Best regards.
I'm going to say no. Not an easy way to add headphones as the output is a bridged output so in other words both wires have voltage on them as opposed to a ground referenced output where one of the speaker wires is grounded.
@@12voltvids Is there any other way to use headphones on the device, or use some kind of adapter, perhaps taking advantage of the USB port? Again I want to thank you for your advice and the time you spend to advise us. Best regards!!
Not liking the early compression... Not too well suited for inefficient speakers I'm guessing... At least not when you expect it to reach high output/volume
Iam new to the audio stuff so be nice please, I just looked up BTL and it says bridged tied load where one amplifier feeds a second amplifier a inverse signal which doubles the voltage swing giving 4X the power. Is this correct? and if so ia this unit using 4 channels BTL configured to give a sterio at the 50 watts a channel.. I am just confused..lol
Yes that is correct. They use 2 amplifiers per channel. This was an old trick used in the analog amp world of car boosters 40 years ago. A 12 volt power amp chip would put out about 10 watts. So they would put a second one in and feed it an inverted signal using and the resulting output would be an inverted signal. Hook the 2 outputs to the speaker terminals and you have double the output from the same supply voltage. Better amps naturally used a DC-DC converter to step up the supply voltage. These class D amps do the same thing. That is why there are the 4 big coils and 4 blue caps in the back. Those are the low pass filters for the 4 channels, 2 channels per side.
If you plug a cell phone into the USB unput and your cell phone is in file transfer mode it will treat it as a USB drive and play the music files. It will also charge your cell phone. Never tried connecting to computer. If you plug in a USB stick, it will play the files just like from an SD card.
In case of a PC with Windows, it should appear as a DAC device, surely a speaker for USB Audio, (probably JeiLi AC46) which is a very high definition sound as it's digital instead of analogic. in the SMSL can be seen something telling that is a PC connected. If it's a cell phone act as you said. But if you have an app called USB AUDIO PLAYER PRO you can play the same as explained above. USB audio digital sound. It would be great if you plug this device to a PC- In such case I would like to buy an SMSL It seems that this model is discontinued (not sure)
t0nito Bluetooth would make it perfect but I am not complaining. For me this is perfect because as I said on the video I don't have files on my phone and I don't stream audio services. I have a USB port in my car and all my music is on USB sticks so this is perfect. Just plug in a stick of SD card and let it go. When I had my real BlackBerry I could listen to music and not be interrupted by messages but on android even if I am playing through Bluetooth I get the audio alerts for incoming messages. Yada Yada Yada I know I can then off alerts but then I miss it important alerts. On my old BlackBerry music would play out Bluetooth and alerts through the phone speakers. I use my old z30 to play music and listen to internet radio. So this is perfect just load a memory card and let it rip. I could plug my Bluetooth receiver into the analog input if desired and then I have best of both worlds.
They are royalty free tracks. Most are from the musicbakery.com, the last guitar track I played is from triple scoop music, and it came bundled with Corel video studio. Yes I bought video studio thinking I would like to try something other than premiere as it has lots of cool effects, but never ended up using it because premiere is so much easier to use, and outperforms it is every way. I did end up using the music tracks though, as a few of them are really good. Not up to Jack Waldenmeier of the Musicbakery's standards, but still pretty good.
Yes you can connect anything through the AUX jack. All you need is a 3.5 to phono plug adapter. What you can't do is have an analog and optical input connected at the same time as it is a hybrid plug. I mar try to put a separate toslink jack on the back if I get bored some day.
It is full digital right to the low pass filter which converts the PWM waveform, which is digitally converted from PCM to PWM inside the texas instruments digital amplifier chip. Inside the low pass filter the analog waveform is produced and fed to the speakers. Loop up the specs to the chip. It is digital all the way, including the output which is a rail to rail square wave signal.so it is accurately called a digital amplifier.
Well, that would defeat the purpose. I do have a bluetoooth receiver that has an SD card and USB port that feeds an analog signal that could feed into a tube amp. It will also stream from your phone into a tube amp, and that is what I use it for. Tubes are warm sounding for sure, but a solid state amp has far less distortion, and more punch. Myself I still perfer the sound of class A tubes. That is why I spent 1200 to buy that TU8200 and 400 to build the TU8100 kits. They sound great. I listen to the little 2 watt TU8100 every night when I am going to sleep. Set my old Sandisk MP3 player sleep timer, and feed it through the TU8100. The sound at low levels is so good. Even into the speakers I picked up at the second hand store for 7.00 sound really good. Very clear.
I got all excited about this, waiting for you to tell me it was from banggood at a great price then BAM AMAZON, they specifically don't ship to Australia!
At 3:03 you will see on the card advertising their products their official web site. I am sure you can get one there as it says we welcome personal purchase or wholesale inquiries.
Is it an amplifier - or is it digital converter to analog amplifier? Cause the last I check Humans cant appreciate digital sound. Yuh click-bate title might catch the Young, not us who invented it tho. If you want to get the smartest pple to chat with call india! I do that sometimes.
Technically it is digital all the way out to the output of the amplifier. It is a square wave PWM carrier which had 2 states. 1 and 0. So last time I checked a binary signal is infarct a digital signal. The low pass filter that follows changes that pulse width signal which you can't hear into a more familar voltage amplitude signal that will make the voice coil on the speaker move, which moves the cone, which in turn moves the air that in turn changes the air pressure on your ear drum that stimulates the nerves in the inner ear which your brain interprets as sound. Is that simple enough for you trolls?
Are you presuming to tell me about audio? I worked in audio engineering for 20 years. I had super Sense of smell and hearing (Took all Precautions too), along with my removed Cataracts at 6 and 11, lost hearing one ear on 13 dec 2016, and smell 5 july 2014 when My epilepsy came back, cause of all the FlatEarth shit that took half a millennium to work out where we live, now some jobless anyway... These eidots cant even understand how ah Transistor work but can tell you everything else about a bigger universe? And I am not a troll, but I do have Very Bad Tinnitus.
Not bad, but those speaker wires running 2 wires for neg and 2 for pos instead of one thick wire will put out less power making the wires warm to hot in time, just kidding. lol
class d amplifiers are never digital in the binary data sense, it's a misnomer. It may appear digital as it's off and on but its not binary data. Class d is not an amplified pulse train of one's as you can't amplify zero, digital being a numeric representation of something, a series of ones and zero's in binary transmission (like the dsp portion). Even the TI tas5766 has a dac stage prior to the class d stage (pins 13, 36) that you can tap off of to go to whatever amplifier you like or be fed back into the chips on board class d amplifiers through pins 12, 37. But If you stretch the term digital, a numeric representation, and assume the finite values of numeric representation are not finite, then maybe you could call it a digital amp.
Class D are PWM amplifiers, or switching amplifiers. The comparison to digital is that they are NOT a linear amplifier. The MOSFET is either full on, or full off. No in between. . There are many forms of modulation in the digital domain. Pulse Code Modulation, Eight Fourteen Modulation, and yup you guessed it Pulse Width Modulation. I hope this clears things up for the "internet experts" that think they know everything. Class D is "digital" for sure because to be "digital" the waveform has to be represented in one of 2 states, and the output from a class D amplifier is clearly a binary output. The PULSE WIDTH MODULATION output, which incidentally is full rail to rail is filtered by the low pass filter, and the analog waveform is recovered. See, you learned something today! Most people think that it has to be PCM to be digital, and this is definitely not the case. When you take your analog input, and mix it with your triangle waveform and run it into your comparator which will create your PWM signal based on the incoming signal. You can think of it as a pulse train, but it is still 1 and 0. Meets the definition of digital.
12voltvids class d is not a quantized digital representation of an analog signal. It is a continuously and infinitely variable series of fixed period intensity measurements and has nothing to do with digital signal conversion or transfer. You seem to have glazed over the fact that even the ic in your device has a dac prior to the amplifier stage.
It has NOTHING to do with quantizied PULSE CODED MODULATION where you assign a numeric code for a given period of time. A class D amplifier works on a continuously variable pluse train. It has nothing to do with assigning a number or code. It is a variable duty cycle, much like FM or frequency modulation, where a carrier wave varies in frequency with the rise and fall of the analog signal modulating it. IN PWM case, the frequency is constant, and the duty cycle changes as the ANALOG incoming signal rises and falls. These amplifiers do have a DAC, directly ahead of the electronic attenuator, and the output of that is passes to the comparator where it assigned a duty cycle and fed, as a DIGITAL signal, not a PCM digital signal, but a PWM digital signal to the output switching transistors for the voltage or amplification gain. A class D amplifier is still classified as a digital amplifier because the amplified signal is a string of 1 and 0 representing the incoming analog wave it is amplifying. Confused yet?.
I'm not confused at all, but we will have to agree to disagree. class d is not digital, it is not an amplified representation of 1 or 0 in a string. It is discrete continuously variable fixed period intensity measurements, regardless of the modulation scheme, that is what is being amplified. One of the criteria for digital is a finite set of quantized values to represent the approximate analog waveform, wether its binary, ternary, map, or any other set of finite value, class d does not conform to this criteria as its value is not numerically represented or quantized, it is infinitely variable.
I just recently bought an SMSL SA-300 for my bedroom. Has a line-level input as well as Bluetooth 5.0 and USB DAC (connected to a computer) for my bedroom. Seems SMSL really is on a mission to build good quality stuff. My little SA-300 drives a pair of Phase Technology 2.5 bookshelf speakers quite handily. The sound quality from all sources is quite impressive!
The sound your camera recorded is far better than average. I can tell that unit has a nice clean sound to it.
This well made little amp and a pair of inexpensive, but great speakers like the Dayton B652-AIR are your ticket to great sound 'on the cheap'!
I am running a pair of PSB mite and it sounds really good.
Nice review. I like the display and the compact size although the tiny letters would be difficult to see without reading glasses. The other two shortcomings are the limited capacity to accept files and the lack of Bluetooth. Thanks for sharing!
Cat3 cable is actually fine for amps / speakers tbh.
There was (and probably still is) a "fad" on certain audio forums where people made speaker cables by braiding a few lengths of Cat5 together.
It's supposed to result in quite low inductance etc., but that's definitely verging on "audiophool" territory. lol
(I used some braided Cat5 on my own front speakers for a few years, but normal copper speaker cables are cheap enough now to not go to that effort.)
Some people put way too much emphasis on speaker cables tbh.
Granted, if you're lucky enough to afford speakers costing $5,000 or more, then you'll want better cables too, but for most people, a simple stranded copper cable with a decent cross-section (for higher current) will be fine.
Anything much more expensive is usually overkill for most home (and even home theatre) use.
Obviously it's a different requirement in very large rooms / theaters / studios / stadiums, but that usually just means thicker more robust cables with expensive Neutrik connectors etc.
thanks 4 the review. is remote controller made of metal or plastic?
That dual function jack has a optical input function but a small adaptor plug is required to convert the toslink to jack format.
Right, a TOSLINK to 3.5 toslink adapter. I have one, came with my MZ1 minidisk as it used the same dual 3.5 jacks.
What interests me about this unit is the optical input. Ive been looking for a small, inexpensive amplifier that has optical, for powering vintage hifi speakers on a PC.
Thumb up for your speaker wires :-) I like it
SMSL AD18 has bluetooth, coax and optical input. It also has the same great build quality and low price
Have you compared with SMSL B1 in a sound quality?
I see it says in the manual it can handle 4ohm speakers, but what about 8ohm speakers, it is a very nice unit. This would make a great amp for my Chromecast Audio.
Works fine into 8 ohms, Rated power will be a little less as an 8 ohm speaker isn't going to draw as much current. The speakers I tested it on are 8 ohm speakers, and you hear the sound quality. It sounded great, and puts out enough volume to generate a noise complaint.
It is a very smart and compact device, very nice :-D
The insides do look clean and well designed, nothing naughty or nasty.
For me, i would want a button for the menu select, not a shared rotary/button, but that's just my taste, and yes the display could have been bigger.
Failures would be the switchmode brick, it will be an unknown special, they go poof lol.
zx8401ztv
Some bricks last a long time. being 19v I would guess this is a standard laptop brick.
nice construction, and it sounds good on this end.
Nice peace of kit, how much would it cost in the U.K
that lp i i know there is no way i could get a copy of that but iam a Hammond B3 Jazz organ player would like to know the tune Dave and have you buy any chance have This to a PC Clean up progam to take out all the pops
Amazing sound. Considering I am listening to it through a cheap Lepai LP-838...
Thank you for that lovely Music in the end
Looking at the front panel it looks like it has capability of IR control. I just saw you mentioned remote so if it's an actual IR remote that's pretty cool. I would love to see that tube amp! And I'd like to see a teardown of the unit.
Yes it comes with an IR remote.
I would love to see that tube amp too, as I have 3 modern tube amps now, 2 which I built, and I also have a vintage McIntosh MAC1500 which I will rebuild one of these days.
if they would include a dab+ tuner it would be heaven.
Did you try the optical input? it will be better for connection to tv box than aux?
CUE: Bin and Cue, CD Audio file system. BIN is the data and Cue is the track information.
I've had this amp for a year or two now, and it's been fine for it's purpose (2 bookshelf speakers) but a few weeks ago I noticed the display brightness was very, very low. To the point where I couldn't see it in sunlight, you can only see it when it's dark and even you need to get close to it to see. I've looked through the settings and there's nothing for brightness, only the timeout options. I've searched online and haven't found anything. Any suggestions? Seems silly to replace it just because the display is slowly failing - everything else works as it should.
Its an OLED display. They do get dim. My phone screen is getting dim now too. The oled on my car charger is the same. They are all based on phosphor and it wears our.
Interesting approach. I wonder how it performs against DACs and class A/B amps.
They are much more efficient than A/B designs, and have very low distortion figures. Most people wouldn't be able to tell the difference in blind listening tests. Sure the hard core believers will try to sway your opinion, just like they try to convince everyone that vinyl is better than full digital, or that #2 gauge speaker wire, and 1000.00 interconnect wires is going to make a difference in sound, but put them in a room with 2 speakers, and not tell them which amplifier was driving those speakers and they won't be able to pick a winner.
Now this is not true when comparing to tube gear, and the tube gear will generally win. Not because they are better, in fact no tube amp can even come close to a solid state amp as far as dynamics or distortion levels, but tubes add their own colorization to music that makes them sound pleasing and less sterile which many people favor, and will pick the tube amp every time as sounding better. I tend to agree, a class A tube amp is hard to beat for a musical sound, even though it has much more distortion and the frequency response more resembles a camels back than a ruler.
Nice, but I don't understand how the Aux input can take a 3.5 Jack and a optical Toslink?
Yes it is a hybrid plug. You can put in a standard stereo 3.5mm, and it also has a toslink input in the base of the plug. A toslink 3.5mm adapter is used. It looks like a regular 3.5mm plug but it is plastic and has the optical fiber inside it.
You can't have both at the same time, it is either analog copper, or digital optical.
This is a Class D amp, which is actually analogue. :) I think they must call this "digital" because it has a DAC onboard.
It does have a DAC, but many times they refer to class D as digital because of the way the outputs work.
The output is a square wave which can be represented as 1's and 0's!
Yes the output is digital, there are only 2 states on and off. 1 and 0.
The analog signal is convered into a PWM, pulse with moulation signal, which is represented as a 1 or 0 with the duty cycle changing to follow the analog input much like FM radio. FM radio the frequency changes to follow the audio signal, PWM the frequency remains constant, just the duty cycle changes.
The audio signal is still represented as a digital signal it is just not encoded into anything such as PCM or pulse code modulation. The analog signal is represented by an ON - OFF digital carrier, which when the carrier is stripped reveals the original analog signal, amplified.
@@12voltvids So if I plug in a cd player to its aux in, does it bypass the dac built in the amp or not? I like my cd player to use its dac when connected to the smsl.
@@automachinehead goes through a AD converter, so the Amp can process it. This amp is digital as in 1s and 0s
i prefer all my 80s amps.
ye but where to hold them in modern times
Why is the RF shield missing? Did you open it, remove the shield, and close it back up before making the video?
Ariskayler
I didn't remove any shielding. Why would there be any? It is a metal box so that provides more than enough shielding.
SMSL AD-18 has Bluetooth as well a being a bit more powerful
Is it Available in UAE and how much
Does is play wav and flac from the sd-card?
Somebody wasn't listening at the beginning when I went over the specs.
Yes it supports .WAV and .FLAC from both SD card and USB stick. at the 1:55 point is where I WAV and 2:20 for flac.
Nice review. What's the song at 14:54 ?
Hello, After seeing the your review about this amplifier, i purchased one from amazon. For starters i had problem with the adapter they send with it, i plugged the adapter the light came on the amplifier and stopped instantaneosly, but i had a different adapter voltage was 18V and current about 2Amps it was bit less than the original spec but the amp works they are going to refund for the adapter. But my question is i for some reason placed the meter across the speaker output terminals there was a voltage of 20mV, and with respect to adapter negative terminal and positive speaker output terminal it was measuring about 9volts, is that normal or something wrong with it? Hope to hear from you soon, Thank you and Regards.
These amplifiers use a BTL, or Bridge Tied Load output, so you don't measure between the ground and speaker terminals. You will see a voltage. If you measure between the speaker terminals with a load across the speaker terminals you will see nothing.
How they operate is they generate a PWM switching signal, with the + and - outputs running out of phase with each other. The output MOSFET switch rail to rail so 0 to full B+, be it 18 or 19 volts. They will operate on pretty much anything up to the max rating of the chip. What comes out is a square wave at a very high frequency. Usually around 400KHz As the audio goes positive, the duty cycle increases on the + amplifier, and decreases on the negative amplifier. As the waveform goes to the negative phase, the positive side duty cycle decreases, and the negative side increases. The amount of swing that the PWM signal makes from its resting frequency determines the loudness. If this sound like how FM radio works, well it is very similar. In an FM transmission the duty cycle remains 50/50 and the frequency changes to follow the audio signal. In Phase modulation, the carrier phase changes. Clip a phase modulated sinewave and it starts to look much like a PWM signal, except that in PWM, the switching point is a hard switch, not a sightly sloped angle as a phase modulated carrier would be, but they look similar. This PWM signal is passed through the choke coils and capacitors in the output where the high level rail to rail carrier is removed, and you are left with a very clean signal, and it is clean. Almost too clean for my liking.
I have listened to this little unit quite extensively over the past week, and it does sound very nice, but a bit sterile. I go back to my tube amp on the same speakers, and the music has more body, a fuller more alive sound.
Even though any solid state amp will destroy tube amps on paper, and when measured with test equipment. The tube amplifier, with it's high even order harmonic content just adds a warmth that you have to experience to understand.
There is a reason that some people will pay as much for an amplifier as a brand new car. Sometimes you just can't beat the old school tech.
Hello sir, thank you for your reply, when I measure under load conditions across the speaker terminals I get about 20mV is this is dc-offset? Or will it be okay?
Basil Saverimuttu
20 my is nothing. There will always be a slight DC component after the filter.
Will it accept banana speaker plugs?
don't be embarrassed about what wire you use. I use radioshack lamp light power wire for my front 2 towers powered with Kenwood km-106 125-150w rms@8ohm per channel and thick power extension cable 2 wire + & - no ground for my 4 passive subwoofers powered with 2 Kenwood Basic M2 220w rms@8ohm also using a 2x4 MiniDSP for entire system adjustments.
I'm not. It is the self appointed experts, apparently 12 of them at this count than have a problem with it.
12voltvids
I have also used Ethernet cable for small speaker enclosures that had 4 speakers in each.
Hi, is it possible to connect headphones to the device in any way?, It occurs to me if this is possible. ¿Can a standard 3.5mm stereo headset cable be used in the rear optical input to use it to listen to the headphones? Thank you very much for your time! Best regards.
I'm going to say no. Not an easy way to add headphones as the output is a bridged output so in other words both wires have voltage on them as opposed to a ground referenced output where one of the speaker wires is grounded.
@@12voltvids
Is there any other way to use headphones on the device, or use some kind of adapter, perhaps taking advantage of the USB port? Again I want to thank you for your advice and the time you spend to advise us. Best regards!!
Ho much rate
Not liking the early compression... Not too well suited for inefficient speakers I'm guessing... At least not when you expect it to reach high output/volume
He played 128kbps mp3s what do you expect. I thought it sounded good for $100
Iam new to the audio stuff so be nice please, I just looked up BTL and it says bridged tied load where one amplifier feeds a second amplifier a inverse signal which doubles the voltage swing giving 4X the power. Is this correct? and if so ia this unit using 4 channels BTL configured to give a sterio at the 50 watts a channel.. I am just confused..lol
Yes that is correct. They use 2 amplifiers per channel. This was an old trick used in the analog amp world of car boosters 40 years ago. A 12 volt power amp chip would put out about 10 watts. So they would put a second one in and feed it an inverted signal using and the resulting output would be an inverted signal. Hook the 2 outputs to the speaker terminals and you have double the output from the same supply voltage. Better amps naturally used a DC-DC converter to step up the supply voltage.
These class D amps do the same thing. That is why there are the 4 big coils and 4 blue caps in the back. Those are the low pass filters for the 4 channels, 2 channels per side.
i wish the USB input could actually act as a DAC.
Is the watch Casio?
Mr.Sojek
Yes an old solar powered with a radio receiver to pick up the nist time signal.
What happens is you connect a PC or cell phone to USB?
If you plug a cell phone into the USB unput and your cell phone is in file transfer mode it will treat it as a USB drive and play the music files. It will also charge your cell phone. Never tried connecting to computer.
If you plug in a USB stick, it will play the files just like from an SD card.
In case of a PC with Windows, it should appear as a DAC device, surely a speaker for USB Audio, (probably JeiLi AC46) which is a very high definition sound as it's digital instead of analogic. in the SMSL can be seen something telling that is a PC connected.
If it's a cell phone act as you said. But if you have an app called USB AUDIO PLAYER PRO you can play the same as explained above. USB audio digital sound.
It would be great if you plug this device to a PC- In such case I would like to buy an SMSL
It seems that this model is discontinued (not sure)
nice little unit this, might get one for my new ryzen pc, my only issue with this is OLED screens, they fade very quickly.
That would be why they have the dim and blank option.
Would've been nice if it also had bluetooth.
t0nito
Bluetooth would make it perfect but I am not complaining. For me this is perfect because as I said on the video I don't have files on my phone and I don't stream audio services. I have a USB port in my car and all my music is on USB sticks so this is perfect. Just plug in a stick of SD card and let it go. When I had my real BlackBerry I could listen to music and not be interrupted by messages but on android even if I am playing through Bluetooth I get the audio alerts for incoming messages. Yada Yada Yada I know I can then off alerts but then I miss it important alerts. On my old BlackBerry music would play out Bluetooth and alerts through the phone speakers. I use my old z30 to play music and listen to internet radio. So this is perfect just load a memory card and let it rip. I could plug my Bluetooth receiver into the analog input if desired and then I have best of both worlds.
There probably is a bt version in smsl
SMSL Ad-18
WMA is STILL being used?
Might not be used much these days, but this unit supports it.
What is the price? thx..
If you go to the link in the description it will take you to Amazon USA or Amazon Canada and the price will be listed there.
any chance someone could tell me if this will drive a pair of kef q150 and a 10" sub efficiently
Where did you get the songs on the usb stick from??
They are royalty free tracks. Most are from the musicbakery.com, the last guitar track I played is from triple scoop music, and it came bundled with Corel video studio. Yes I bought video studio thinking I would like to try something other than premiere as it has lots of cool effects, but never ended up using it because premiere is so much easier to use, and outperforms it is every way. I did end up using the music tracks though, as a few of them are really good. Not up to Jack Waldenmeier of the Musicbakery's standards, but still pretty good.
耳擴有用？！-充电篮芽沒有？A U x 在嗎？
That wire is called improvise
How to order this amp
Nice sound in a compact design. Just add Bluetooth and would be even better
can i connect a radio or tuner
Yes you can connect anything through the AUX jack. All you need is a 3.5 to phono plug adapter. What you can't do is have an analog and optical input connected at the same time as it is a hybrid plug. I mar try to put a separate toslink jack on the back if I get bored some day.
interesting this thing.
Digital? Well DSP. Speaker drive is still Analogue.
It is full digital right to the low pass filter which converts the PWM waveform, which is digitally converted from PCM to PWM inside the texas instruments digital amplifier chip. Inside the low pass filter the analog waveform is produced and fed to the speakers. Loop up the specs to the chip. It is digital all the way, including the output which is a rail to rail square wave signal.so it is accurately called a digital amplifier.
Well, that would defeat the purpose. I do have a bluetoooth receiver that has an SD card and USB port that feeds an analog signal that could feed into a tube amp. It will also stream from your phone into a tube amp, and that is what I use it for.
Tubes are warm sounding for sure, but a solid state amp has far less distortion, and more punch. Myself I still perfer the sound of class A tubes. That is why I spent 1200 to buy that TU8200 and 400 to build the TU8100 kits. They sound great. I listen to the little 2 watt TU8100 every night when I am going to sleep. Set my old Sandisk MP3 player sleep timer, and feed it through the TU8100. The sound at low levels is so good. Even into the speakers I picked up at the second hand store for 7.00 sound really good. Very clear.
Just stick a BT receiver into a tube amp. Done!
Thanks, mate. Looks interesting. I might not have understood. Speakers are still an Analogue device, is what I meant.
Mitchell McCreath
Of course they are as are your ears.
Good on you reusing that cable
I got all excited about this, waiting for you to tell me it was from banggood at a great price then BAM AMAZON, they specifically don't ship to Australia!
Amazon in your country may have it. I put the link up for Amazon.ca
The only thing amazon will deliver in Australia is books every other time it says "this it item is not available in your country"
At 3:03 you will see on the card advertising their products their official web site. I am sure you can get one there as it says we welcome personal purchase or wholesale inquiries.
Says it ships to australia albeit expensive
Mentorcase amazon australia's crap
40w in, 100w out? Is not a class T, it is a class ET
Because 19V * 6,3A = 40W?
Is it an amplifier - or is it digital converter to analog amplifier? Cause the last I check Humans cant appreciate digital sound. Yuh click-bate title might catch the Young, not us who invented it tho. If you want to get the smartest pple to chat with call india! I do that sometimes.
Technically it is digital all the way out to the output of the amplifier.
It is a square wave PWM carrier which had 2 states. 1 and 0. So last time I checked a binary signal is infarct a digital signal. The low pass filter that follows changes that pulse width signal which you can't hear into a more familar voltage amplitude signal that will make the voice coil on the speaker move, which moves the cone, which in turn moves the air that in turn changes the air pressure on your ear drum that stimulates the nerves in the inner ear which your brain interprets as sound. Is that simple enough for you trolls?
Are you presuming to tell me about audio? I worked in audio engineering for 20 years. I had super Sense of smell and hearing (Took all Precautions too), along with my removed Cataracts at 6 and 11, lost hearing one ear on 13 dec 2016, and smell 5 july 2014 when My epilepsy came back, cause of all the FlatEarth shit that took half a millennium to work out where we live, now some jobless anyway... These eidots cant even understand how ah Transistor work but can tell you everything else about a bigger universe? And I am not a troll, but I do have Very Bad Tinnitus.
@@Raul_Gajadhar google class D mr engineer. Bs detector and do your own research
Not bad, but those speaker wires running 2 wires for neg and 2 for pos instead of one thick wire will put out less power making the wires warm to hot in time, just kidding. lol
Does anyone have a need for left and right balance control?
Well, if you are sitting closer to one speaker, then the balance control is pretty important.
Kinter MA 180 has balance control. Works well with Chromecast for whole house audio.
Good
Unfortunately completely sold out.
I bet they are now, but I am sure they will get more.
Bluetooth would be easy to add parallel to the analog imput.
My little bluetooth board will plug into the analog input quite nicely.
Nice
class d amplifiers are never digital in the binary data sense, it's a misnomer. It may appear digital as it's off and on but its not binary data. Class d is not an amplified pulse train of one's as you can't amplify zero, digital being a numeric representation of something, a series of ones and zero's in binary transmission (like the dsp portion). Even the TI tas5766 has a dac stage prior to the class d stage (pins 13, 36) that you can tap off of to go to whatever amplifier you like or be fed back into the chips on board class d amplifiers through pins 12, 37. But If you stretch the term digital, a numeric representation, and assume the finite values of numeric representation are not finite, then maybe you could call it a digital amp.
Class D are PWM amplifiers, or switching amplifiers. The comparison to digital is that they are NOT a linear amplifier. The MOSFET is either full on, or full off. No in between. . There are many forms of modulation in the digital domain. Pulse Code Modulation, Eight Fourteen Modulation, and yup you guessed it Pulse Width Modulation.
I hope this clears things up for the "internet experts" that think they know everything. Class D is "digital" for sure because to be "digital" the waveform has to be represented in one of 2 states, and the output from a class D amplifier is clearly a binary output.
The PULSE WIDTH MODULATION output, which incidentally is full rail to rail is filtered by the low pass filter, and the analog waveform is recovered.
See, you learned something today! Most people think that it has to be PCM to be digital, and this is definitely not the case. When you take your analog input, and mix it with your triangle waveform and run it into your comparator
which will create your PWM signal based on the incoming signal. You can think of it as a pulse train, but it is still 1 and 0. Meets the definition of digital.
12voltvids class d is not a quantized digital representation of an analog signal. It is a continuously and infinitely variable series of fixed period intensity measurements and has nothing to do with digital signal conversion or transfer. You seem to have glazed over the fact that even the ic in your device has a dac prior to the amplifier stage.
It has NOTHING to do with quantizied PULSE CODED MODULATION where you assign a numeric code for a given period of time.
A class D amplifier works on a continuously variable pluse train.
It has nothing to do with assigning a number or code.
It is a variable duty cycle, much like FM or frequency modulation, where a carrier wave varies in frequency with the rise and fall of the analog signal modulating it. IN PWM case, the frequency is constant, and the duty cycle changes as the ANALOG incoming signal rises and falls. These amplifiers do have a DAC, directly ahead of the electronic attenuator, and the output of that is passes to the comparator where it assigned a duty cycle and fed, as a DIGITAL signal, not a PCM digital signal, but a PWM digital signal to the output switching transistors for the voltage or amplification gain.
A class D amplifier is still classified as a digital amplifier because the amplified signal is a string of 1 and 0 representing the incoming analog wave it is amplifying. Confused yet?.
I'm not confused at all, but we will have to agree to disagree. class d is not digital, it is not an amplified representation of 1 or 0 in a string. It is discrete continuously variable fixed period intensity measurements, regardless of the modulation scheme, that is what is being amplified. One of the criteria for digital is a finite set of quantized values to represent the approximate analog waveform, wether its binary, ternary, map, or any other set of finite value, class d does not conform to this criteria as its value is not numerically represented or quantized, it is infinitely variable.
Wow
nice