SMSL A300 Stereo Amplifier Review

[Lord Whimsey]

The power cord was something I had leftover from a much more expensive system.
If you need technical support for the idea that power cords affect the sound, EE students at University of Toronto found that better cords improved slew rate and distortion specs.. I've found that good entry level cords can provide great bang for the buck. Depending on the circumstances they can make a bigger difference than anything in the wire game.

From what I've seen this site doesn't provide any specifications to meaningful describe sonic differences in high end gear. For example, what factors are responsible for the sonic differences between Audionet, D'Agostino, and Goldmund amplifiers?

As such, this site is just another "I'm smarter than the hobby" site. This isn't very smart, or even participating in the hobby.

 

[ahofer]

The power cord was something I had leftover from a much more expensive system.
If you need technical support for the idea that power cords affect the sound, EE students at University of Toronto found that better cords improved slew rate and distortion specs.. I've found that good entry level cords can provide great bang for the buck. Depending on the circumstances they can make a bigger difference than anything in the wire game.

From what I've seen this site doesn't provide any specifications to meaningful describe sonic differences in high end gear. For example, what factors are responsible for the sonic differences between Audionet, D'Agostino, and Goldmund amplifiers?

As such, this site is just another "I'm smarter than the hobby" site. This isn't very smart, or even participating in the hobby.

 

[Bleib]

Toronto found that better cords improved slew rate and distortion specs..

This should be easy to demonstrate yet is never done. And even if it had any difference to an amp it still wouldn't improve the much, much higher distortion rate speakers have.

The problems with this amp won't be solved by a(ny) cable. Like the fact that display leaks some noise into the signal. It won't fix the frequency response either.

This hobby is absolutely filled with snake oil rubbish

 

[Toku]

The power cord was something I had leftover from a much more expensive system.
If you need technical support for the idea that power cords affect the sound, EE students at University of Toronto found that better cords improved slew rate and distortion specs.. I've found that good entry level cords can provide great bang for the buck. Depending on the circumstances they can make a bigger difference than anything in the wire game.

From what I've seen this site doesn't provide any specifications to meaningful describe sonic differences in high end gear. For example, what factors are responsible for the sonic differences between Audionet, D'Agostino, and Goldmund amplifiers?

As such, this site is just another "I'm smarter than the hobby" site. This isn't very smart, or even participating in the hobby.

The purpose of ASR is to provide a forum for discussing audio equipment technically based on electrical measurement data. Until now, ideas like yours have been dominant among audio fans, and sometimes have become religious.
ASR was started with the aim of eliminating these vague subjective evaluation judgments and evaluating them technically. Therefore, you should understand this before participating in the discussion.
However, current measurement technology cannot fully explain audio equipment. I have been involved in product development, and I believe there are many unknown factors that affect sound quality.
It will probably take some time to figure out what they are.

I also purchased and evaluated two A300s. I understand your questions about sound quality. I believe that this is not limited to the A300, but is common to all Class D amplifiers.

 

[Roland68]

The power cord was something I had leftover from a much more expensive system.
If you need technical support for the idea that power cords affect the sound, EE students at University of Toronto found that better cords improved slew rate and distortion specs.. I've found that good entry level cords can provide great bang for the buck. Depending on the circumstances they can make a bigger difference than anything in the wire game.

From what I've seen this site doesn't provide any specifications to meaningful describe sonic differences in high end gear. For example, what factors are responsible for the sonic differences between Audionet, D'Agostino, and Goldmund amplifiers?

As such, this site is just another "I'm smarter than the hobby" site. This isn't very smart, or even participating in the hobby.

I would be very interested in the link to the topic you mentioned from the University of Toronto.

By the way, I removed my A300 and the AO300 (the amplifier section and power supply are identical) from my desktop setup a long time ago, as there are much more transparent amplifiers available for around €200. The A300, with its bridge circuit and 400 watts into 4 ohms, is an affordable and powerful subwoofer amplifier.

 

[torgeirs]

The Infineon MA5332 chip has some intrinsic qualitys that provides slam. It gets the least hot of all chip amps for 4 ohm load. So we can slam on without meltdown.
200watts btl into 8 ohms is actually sustainable for that chip

 

[ahofer]

“Intrinsic slam” sounds like a decent band name.

 

[Roland68]

The Infineon MA5332 chip has some intrinsic qualitys that provides slam. It gets the least hot of all chip amps for 4 ohm load. So we can slam on without meltdown.
200watts btl into 8 ohms is actually sustainable for that chip

Definitely, including mediocre transparency, intermodulation distortion, and load dependence.
But since I removed it from the setup, it has proven itself to be an extremely potent subwoofer amplifier in BTL mode.

But what are these "some intrinsic qualities that provide slam" characteristics?
Either it reproduces the existing music signal accurately, or it does a very poor job. This is a point that many people don't understand.

 

[torgeirs]

It is cool. To be more presice the output impedance of the transistors is really low. Heat over time is not good, so less heat over time is good.
And -60 dB thd is actually sufficient for slam

 

[Roland68]

It is cool. To be more presice the output impedance of the transistors is really low. Heat over time is not good, so less heat over time is good.
And -60 dB thd is actually sufficient for slam

This has nothing to do with the output impedance of the transistors, but rather with the high switching frequency. We're talking about a PWM-controlled CLASS D chip amplifier here.

Even a low temperature isn't necessarily a good thing if you're familiar with temperature-dependent operating points and their stability in components.

 

[torgeirs]

Have you read the tecnical documents from Infineon?
All transistors has loss that generates heat

 

[torgeirs]

MA5332MS - Infineon Technologies

The MERUS™ MA5332MS multichip module offers the same or even higher output power as monolithic alternatives without a heatsink and 50 percent less footprint.

www.infineon.com

Check out the videos section

 

[torgeirs]

Just to be clear. Output impedance was not really accurate. On resistance is the right term. From the Infineon site:

The latest MERUS™ audio amplifier, MA5332MS has the lowest RDS(on) class D output stage among all integrated amplifier solutions today. It enables heatsink-less operation and delivers 50% higher power density than its predecessor as well as other alternatives

 

[Roland68]

Have you read the tecnical documents from Infineon?
All transistors has loss that generates heat

MA5332MS - Infineon Technologies

The MERUS™ MA5332MS multichip module offers the same or even higher output power as monolithic alternatives without a heatsink and 50 percent less footprint.

www.infineon.com

Check out the videos section

Just to be clear. Output impedance was not really accurate. On resistance is the right term. From the Infineon site:

Great advertising babble, but it doesn't change the problems and limitations that Merus-based amplifiers have.
Even cute promotional videos don't change reality.
I don't know what you're trying to tell me.
If you're happy with it, that's fine.
I abandoned this technology after several evaluation boards with Merus MA12070 and MA5332, as well as a few SMSL and SABAJ amplifiers with these chips, because I didn't want to waste any more time on it.

 

[ahofer]

A request: Please describe slam in a way that people can understand similarly. Or don't use it to recommend or describe audio components.. If you mean impulse response, low frequency presence/amplitude, low bass distortion at high power, or something like that, say so. Otherwise it's just a feeling, and everyone will know it somewhat differently.

 

[torgeirs]

This has become a thread of feelings. Seems no one is interested in science here

 

[Roland68]

This has become a thread of feelings. Seems no one is interested in science here

Science is the limit of this technology. Look at the measurements and limitations of the A300. This is consistent with all other tests of Infineon-based amplifiers.

 

[torgeirs]

Yes they are great.
But most are implemented with all the gain in power stage so that will give raised distortion in high frequencies because of power bandwith. But still under -60 dB.
No human can hear it

 

[torgeirs]

By the way the 12070 models are different technology that broke (could not handle the current if load disconnected) Those are disconntinued by Infineon

 

[torgeirs]

Even cute promotional videos don't change reality.

Look at the numbers on the lab equipment in the video. They tell the tale of reality. Not feelings
Try to do the same with any other chip on the market. I guess you will smell the smoke.
Or maybe not. They will feel a little warm and shut down