SMSL PA-X Stereo Amplifier Review

[staticV3]

I'm only familiar with GaN in the USB-C charger market. Is its appeal a smaller footprint and less heat generation?

Higher efficiency by way of increased switching frequency, I believe.

Here's SMSL's marketing slide on the matter (ignore "enhancing sound clarity" ):


Source

 

[Roland68]

I'm only familiar with GaN in the USB-C charger market. Is its appeal a smaller footprint and less heat generation? I remember that being the marketing for the GaN phone chargers I've seen

Yes it is amazing how much power can come out of those ridiculously small and completely sealed wall warts. I think there is a chance for very efficient very small power amps somewhere, maybe battery operated boom boxes or something. These gan amps have been around quite a while, I wonder where have they been used.

GaN, or gallium nitride-based semiconductors, are neither a miracle technology nor anything new. It is simply the next stage of development after silicon-based semiconductors, with improved energy efficiency at high switching frequencies, especially at high power levels. GaN cannot be used effectively in conventional analog amplifiers.

And so far, it offers no advantage in audio amplifiers, except in switching power supplies.
Current GaN amplifiers are easily outperformed by non-GaN-based amplifiers, and they are also in a similar price range.

There is no reason to expect significant energy savings when using GaN in the power amplifiers, as the average power in real music is much lower, and the theoretically improved energy efficiency at this point will be well below 10%. Therefore, the effective energy savings achieved by GaN in power amplifiers will be in the single-digit watt range.

In addition, Infineon amplifier technology has had limitations for several generations, especially in terms of load dependence, especially at 4 ohms. GaN does not change this.

 

[Multicore]

Putting aside the unit failure, these features and measurements seem very meh for $700.

• No trigger
• RCA better than balanced
• Fine but not great sinad
• Frequency droop
• Power specs slightly under
• Crosstalk

Given the state of the industry, this is a hard pass.

I think this product is for people who want gallium nitride transistors. It's not more weird to be into that than some other features people enjoy, e.g. density and its oozing feeling of quality.

 

[jackdanyal]

Still not sure why to spend so much on this kind of class D amps if for the same price you can buy smth from Yamaha or Cambridge Audio with much more (reliable and stable) power, more inputs, sub out, sometimes even with 2 pairs speakers connection and better reliability. the only benefit here I see the size of the unit.

 

[Roland68]

Still not sure why to spend so much on this kind of class D amps if for the same price you can buy smth from Yamaha or Cambridge Audio with much more (reliable and stable) power, more inputs, sub out, sometimes even with 2 pairs speakers connection and better reliability. the only benefit here I see the size of the unit.

I'd be cautious with Cambridge, as they've unfortunately had frequent amplifier failures in recent years. Incidentally, I've been a Cambridge fan since day one.

I'm currently using, among other things, the Yamaha A-S1000 and two Sabaj A30as in my setups, all three for over two years and without any problems or failures.
With Yamaha, I would always prefer a used A-S1XXX or 2XXX to a new A-S701. A look inside and the more solid construction speaks volumes.
If I had to choose between the A30a and the A-S1000, I'd probably keep the A30a, especially because it doesn't require a DAC for digital sources and is at least as powerful.

Compared to these two devices, as well as some TPA325x PFFB amplifiers, I can't imagine any reason to buy an SMSL PA-X or PA200.

 

[jackdanyal]

I'd be cautious with Cambridge, as they've unfortunately had frequent amplifier failures in recent years. Incidentally, I've been a Cambridge fan since day one.

I'm currently using, among other things, the Yamaha A-S1000 and two Sabaj A30as in my setups, all three for over two years and without any problems or failures.
With Yamaha, I would always prefer a used A-S1XXX or 2XXX to a new A-S701. A look inside and the more solid construction speaks volumes.
If I had to choose between the A30a and the A-S1000, I'd probably keep the A30a, especially because it doesn't require a DAC for digital sources and is at least as powerful.

Compared to these two devices, as well as some TPA325x PFFB amplifiers, I can't imagine any reason to buy an SMSL PA-X or PA200.

Sabaj has the "same" power unless you will load it. with some load it will struggle much more and will have a ton of distortions. that's the weak point of almost all class D amps nowadays.

 

[Roland68]

Sabaj has the "same" power unless you will load it. with some load it will struggle much more and will have a ton of distortions. that's the weak point of almost all class D amps nowadays.

Where did you get this incorrect information about the Sabaj A30a? Or is this just a general assumption about Class D amplifiers?
Then you may have overlooked the fact that the A30a differs significantly in design and function.

In the SMSL VMV A2 (identical) test, Amir already pointed this out, quote: "As we have seen from other STM measurements, this is one linear amplifier with no care about the frequency or level." The other comments in the test report are extremely positive.
Load dependence is also virtually nonexistent; channel balance and crosstalk are excellent.

There are good reasons why two A30a amplifiers are now here, replacing amplifiers many times more expensive. It also prevented me from purchasing an A-S3200, which I had long planned. And I wasn't the only one. Especially at high power levels, even with impedance-critical speakers, I find it more detailed.

 

[jackdanyal]

nope, I didn't overlooked. I had the same amp actually and now I use Yamaha A-S301. it barely could catch the same amount of volume without any distortion connected to my second pairs of DBR62. The sound wasn't as clear and appealing as from Yamaha. considering that the sabaj is much more powerful than A-S301 on paper. With Wharfedale Diamond 12.2 and Heco Aurora 300s it was fine, those speakers are easy to run. Also I had issues with subwoofer output. it was giving different output volume level on different load. For me that's not acceptable and that kind of issues is a clear picture of state of current chi-fi devices: they try to produce a lot of devices with almost the same specs, with a little bit different design, but QC issues remain the same.

 

[Ismapics]

Big front panel area wasted. All would be forgiven if they had added to meters. Not complicated.

 

[Thomas Savage]

Assuming we belive in the merits of the test procedure that resulted in this device taking its toys home and not wanting to play anymore , then a fail is a fail .

No reason to feel bad , thanks for the review Amirm , are you still going to run this test in the future?

 

[Talisman]

Barely mediocre performance at a high price. We are in the range of hypex modules.
The dependence on the load on this figure is something I can no longer accept.

 

[Roland68]

nope, I didn't overlooked. I had the same amp actually and now I use Yamaha A-S301. it barely could catch the same amount of volume without any distortion connected to my second pairs of DBR62. The sound wasn't as clear and appealing as from Yamaha. considering that the sabaj is much more powerful than A-S301 on paper. With Wharfedale Diamond 12.2 and Heco Aurora 300s it was fine, those speakers are easy to run. Also I had issues with subwoofer output. it was giving different output volume level on different load. For me that's not acceptable and that kind of issues is a clear picture of state of current chi-fi devices: they try to produce a lot of devices with almost the same specs, with a little bit different design, but QC issues remain the same.

I can't understand that, and it sounds more like a defect.
I also have an A30a running on a DBR62 and an Elac Carina BS243.4, but also on much more difficult speakers.
It can easily keep up with the performance of the A-S1000, but at high volumes, the A30a seems to have more bass punch. A friend once brought an A-S501 with him and it couldn't keep up with both of them.
If you're happy with the A-S301, then everything's fine.

I'd like to hear the SMSL PA-X or PA200 for comparison, but they're too expensive for me.

 

[JSmith]

current ***-** devices

Not here, thanks;

Let's Avoid the Term Chi-Fi

I often see the use of the term "Chi Fi" to describe audio products from China. I see the intention and don't think anyone is trying to be racist and what have you. Still, I like us to show the highest respect to products from around the world. As avid readers of this forum know...

www.audiosciencereview.com

Sabaj

Yamaha A-S301

This is a review thread;

Rules for Review Threads

New Rules for Review Threads Reviews of audio products are the crown jewels of our forum. In cooperation with kind members and companies that send in gear, and collective wisdom of the contributing members, we have created an incredible asset for audiophiles. As we cover nearly one new audio...

www.audiosciencereview.com

JSmith

 

[GPx86]

Very disappointed. I was really hyped for this. Seems like a rushed product. I'm getting some friends into stereo and had hoped this would be the new go to recommendation.

 

[Lambda]

How and why Was the combination of Volume setting and input voltage chosen?
It would be interesting to see how Higher input voltage and lower volume setting or vice versa influences the performance.

Listening at "only 5W" with the volume turned almost to the max. dose not sound like a realistic test to me... but im sure there are resone for this

 

[classaistheway]

Thanks for the review Amir!

Did you happen to notice whether the volume control can be bypassed in stereo mode? The SMSL website says it can, but the user manual seems to suggest it can only be done in mono mode.

 

[shuppatsu]

Not here, thanks;

Let's Avoid the Term Chi-Fi

I often see the use of the term "Chi Fi" to describe audio products from China. I see the intention and don't think anyone is trying to be racist and what have you. Still, I like us to show the highest respect to products from around the world. As avid readers of this forum know...

www.audiosciencereview.com

This is a review thread;

Rules for Review Threads

New Rules for Review Threads Reviews of audio products are the crown jewels of our forum. In cooperation with kind members and companies that send in gear, and collective wisdom of the contributing members, we have created an incredible asset for audiophiles. As we cover nearly one new audio...

www.audiosciencereview.com

JSmith

I got my hand lightly slapped for this a few years ago and it’s totally fine. Different forums can set their own norms. I hope that this gets revisited at some point, though. The term is regularly used in other forums without any hint of its being pejorative. Chinese designs and production have revolutionized hifi.

 

[Old_School_Brad]

I can't understand that, and it sounds more like a defect.
I also have an A30a running on a DBR62 and an Elac Carina BS243.4, but also on much more difficult speakers.
It can easily keep up with the performance of the A-S1000, but at high volumes, the A30a seems to have more bass punch. A friend once brought an A-S501 with him and it couldn't keep up with both of them.
If you're happy with the A-S301, then everything's fine.

I'd like to hear the SMSL PA-X or PA200 for comparison, but they're too expensive for me.

Something doesn't quite add up. The A-S501 has, per the usually conservative Yamaha specifications, the same maximum power as the A30a -if we go by the VMV-A2 measurements on ASR, which is also maximum power, -so there's no real indication that the Yamaha wouldn't be able to "keep up" with the A30a..
Could be classic expectations playing tricks?

 

[staticV3]

How and why Was the combination of Volume setting and input voltage chosen?

Amir aims for 5W@4Ω, ~25dB gain hence ~0.25Vrms in for every Amp snapshot at the beginning of his review.

It's to level the playing field.

The specific values are not super important, what's important is that they stay the same for every review.

 

[JeremyFife]

Interesting review - for the use of GaN - thanks for this.

Performance decent, but not good enough for the price - the cost of early adoption perhaps.
Getting used to better load independence in particular.
Shame to see it fail on the 'FTC' sweep. I would have thought it would at least gone into protection and recovered.