Impressions: SMSL PA200 GAN FET Class-D Power Amp

[Deleted member 72219]

We need a full test to show why, but possibly the PA200 has a wider frequency response than the NAD.

I don't see that being the case given the measurements of the NAD:

NAD C298 Stereo Amplifier Review

This is a review and detailed measurements of NAD C298 stereo class D power amplifier based on Purifi Eigentakt modules. It is on kind loan from a member and costs US $2,399. The unit is quite heavy for a class D amplifier. The front is plain as most power amps are. I was not a fan of the...

www.audiosciencereview.com

-Ed

 

[Roland68]

Thank you @goryu, very much appreciated :=)

Let's ask @amirm (for accuracy/clarity) about the SMSL P200 GaN amplifier utiliseing a closed-loop design with post-filter feedback, as indicated by SMSL Shop. @amirm could you please (objectively) clarify for us if the SMSL PA200 utilises post-filter feedback or not and if it does, what type of post-filter feedback? Also as since you have been asked about this, we would like to ask if the SMSL PA200 is in the schedule for the ASR test & measurements review process?.... thank you

Aside from the fact that SMSL has often included incorrect information and errors/misinformation in its descriptions, what the chip manufacturer provides is more relevant and important.

Infinion clearly states in its functional description: "This integrator receives a rectangular feedback waveform from the class D switching stage and outputs a quadratic oscillatory waveform as a carrier signal."

This means that any kind of post filter feedback from the manufacturer Infineon has been excluded. These components simply cannot do that.

 

[Matt_Holland]

I don't see that being the case given the measurements of the NAD:

NAD C298 Stereo Amplifier Review

This is a review and detailed measurements of NAD C298 stereo class D power amplifier based on Purifi Eigentakt modules. It is on kind loan from a member and costs US $2,399. The unit is quite heavy for a class D amplifier. The front is plain as most power amps are. I was not a fan of the...

www.audiosciencereview.com

-Ed

Good point.

 

[JustJones]

When the daughters switch the pre amp on and off the NAD gives the switching sounds to the speakers. The SMSL for some reason stays silent. So with little children the PA200 has it's advantages in my situation.

When there is no music playing the NAD gives a very little noise to the speakers, while the SMSL stays completely silent. Gain is both fixed, no other changes in setup.
When a record has high frequency noise recorded on the track the SMSL (in my setup) gives the noise more presence whereas the NAD 'covers' it.

Looks like NAD has some issues with power off and idle. Might be picking up something.

Power on is silent although there is a pattern in the idle noise which should have been caught and eliminated:

 

[KL....]

Amir doesn't open the devices that he tests often, and when he does, he doesn't always comment about the design. You have better chances convincing an owner to post pictures of the insides (or do it yourself ) and asking the folks in the forum what you want to know.

Thank you, No! If @amirm cannot help and you (and others) cannot help, we will just need to accept that the SMSL Shop is correct, which is that the PA200 utilises a closed-loop design with post-filter feedback, until otherwise advised, won't we?

 

[Deleted member 72219]

Thank you, No! If @amirm cannot help and you (and others) cannot help, we will just need to accept that the SMSL Shop is correct, which is that the PA200 utilises a closed-loop design with post-filter feedback, until otherwise advised, won't we?

Quite the opposite, based on this:

...what the chip manufacturer provides is more relevant and important.

Infinion clearly states in its functional description: "This integrator receives a rectangular feedback waveform from the class D switching stage and outputs a quadratic oscillatory waveform as a carrier signal."

This means that any kind of post filter feedback from the manufacturer Infineon has been excluded. These components simply cannot do that.

However, this is based upon an assumption as to the precise componentry used in the amp. I think we're not 100% confirmed on this piece yet, if I am not mistaken.

-Ed

 

[KL....]

I asked their online support at https://smsl.shop/

Here is the conversation:

SMSL SHOP​

• March 19
• Hello-
  10:45 AM
• Can you tell me if your PA200 GaN amplifier uses post filter feedback or is it open loop? Thank you.
  10:46 AM
• March 20
• Thank you for your technical inquiry! The SMSL P200 GaN amplifier utilizes a closed-loop design with post-filter feedback to ensure optimal performance and stability. If you have further questions about its architecture or operation, feel free to ask! Best regards, SMSL Support Team
  12:24 AM

Seems pretty clear to me.

Thank you @goryu, very much appreciated :=)

 

[goryu]

Quite the opposite, based on this:

However, this is based upon an assumption as to the precise componentry used in the amp. I think we're not 100% confirmed on this piece yet, if I am not mistaken.

-Ed

easiest way to confirm is to measure the frequency response of the amp at different loads. If it varies with load, then it doesn't have post filter feedback.

 

[Deleted member 72219]

easiest way to confirm is to measure the frequency response of the amp at different loads. If it varies with load, then it doesn't have post filter feedback.

I’ve not the necessary tools to do this, hence my push for a real test by ASR.

-Ed

 

[goryu]

I’ve not the necessary tools to do this, hence my push for a real test by ASR.

-Ed

Send your amp to Amir.

 

[Deleted member 72219]

Send your amp to Amir.

Sent him a DM to gauge interest/capacity.

-Ed

 

[goryu]

Well, different day, different answer from SMSL:

Here’s your response from SMSL SHOP​

Me: Can you tell me if your P200 GaN amplifier uses post filter feedback or is it open loop? Thank you.

SMSL SHOP Thank you for your technical inquiry! The SMSL P200 GaN amplifier utilizes a closed-loop design with post-filter feedback to ensure optimal performance and stability. If you have further questions about its architecture or operation, feel free to ask! Best regards, SMSL Support Team

Me: Was this answer provided by a human or ai bot? Thank you.

SMSL SHOP If you are asking whether the PA200 is equipped with PFFB, I am sure that it is not. I am a human being, just more polite and my tone of voice is more formal when answering questions.

 

[KL....]

easiest way to confirm is to measure the frequency response of the amp at different loads. If it varies with load, then it doesn't have post filter feedback.

Thank you, yes, until then the @EddNog ASR impressions Stand/Evidenced, aren't they?

Note that the PA200 can accept RCA/Stereo or XLR/Mono, can't it?

These are the SMSL measurement graphs....

It could be suggested this graph is why GaN Tech requires/deserves close attention/inspection, doesn't it?

The following graphs suggest/indicate an acceptable Implementation, don't they?

 

[Loba]

It it could be suggested, why wonder? You could simply purchase the SMSL PA200, to compare to the Fosi V3, with your (unchanged) speakers, can't you? This is an objective approach, isn't it? If you do not like the PA200 then you can return it for a refund and post your like or dislike impressions in this thread, can't you?

A point to consider, though.... @EddNog, did you notice a QC/Test sticker with your units (an objective process, isn't it? usually on rear or bottom panel) or QC/Test indications on the SMSL website)? If no, then until clarifyed, the purchaser is the QC/Tester, aren't they? As such, @Loba, if you do purchase an SMSL PA200 then you should test it (perhaps playing music through it for 10-12hrs/day) to test its robustness and evaluate it at the same time, shouldn't you?

If you like it, enough, then you will probably keep it but regardless and after, you can still recap the speaker crossovers, can't you?.... enjoy :=)

edit: if you do purchase a PA200, keep it, and post your impressions in this thread then after you recap the speaker crossovers then you can edit your original/impressions post and add your impressions of the PA200 with the recaped speaker crossovers, can't you? If others ask then you can direct them to your post.... enjoy :=)

thanks for sponsoring my PA200 before I sell my V3 monos! Jokes aside, I do not want too many amps on hand, I still have my arcam solo uno integrated streaming amplifier unsold...

 

[Julf]

When there is no music playing the NAD gives a very little noise to the speakers, while the SMSL stays completely silent. Gain is both fixed, no other changes in setup.

Gain is fixed, but is it equal?

 

[Loba]

On your first point--I suppose it simply depends on how good the return policy is for his reseller for the PA200. I get that not everyone necessarily has access to great return policies like those of Amazon (Prime) or Apos.

On your second point--I have no idea on this. Is it somehow mandatory to disclose whether or not a product is final-QC'd in other countries? Here in the US, I do not believe it is mandatory to indicate if an item is actually final-QC'd.

On your third point (I know, not directed to me)...and I understand of course that it isn't necessarily a direct correlation, but if he's willing to recap speakers almost as old as I am as opposed to looking into new ones with potentially much better objective performance, then either he REALLY, really loves those speakers, or there is a budget constraint there, and just recapping his speaker's crossovers is a LOT cheaper than new amps, hence my original suggestion because I am looking at cost:benefit ratio and moving from V3 Monos to PA200 is expensive with very minimal to no (noticible) gain, even potentially detrimental given V3 Monos have better objective results.

-Ed

aint no budget to get new speakers and the DM3000s are still giving newer speakers a run for its money despite being ancient. I also kept a set of spare NOS tweeters and woofer drivers. They feature a time delay tweeter, a design element that allows for phase-coherent performance, meaning the tweeter's output is timed to arrive at the listener's ear at the same time as the other drivers, resulting in a more accurate and natural sound. This occurs no matter where you position yourself in the room.

Recapping them will probably cost as much or more than your low to mid end amps in my country. 1 of the huge iron inductor alone is US$100 and I will need 2. There are other resistors and capacitors that need replacing, those cost less but number quite a bit and these are just part costs alone, excluding the soldering and labour cost involved.
The circle of B&W DM3000 claims that these set of speakers love lots of power hence looking at PA200. The alternatives would be Hypex Nilai500DIY mono blocks x 2 each which would give up to 190W max power at 8ohms, 494W at 2ohms with "still quite clean" power , be almost twice the cost of PA200 which gives 250W max power at 8ohms. question is whether power is continuous or not and whether PA200 is still quite clean power at lower ohms is something to be measured...

having saying that, V3 monos on standby sucks 5W each and stays pretty warm in my tropical climate near the equator, and my electrical bill has gone up hence considering cooler and more powerful options.

 

[Sokel]

having saying that, V3 monos on standby sucks 5W each and stays pretty warm in my tropical climate near the equator, and my electrical bill has gone up hence considering cooler and more powerful options.

What do you mean standby?

 

[Roland68]

However, this is based upon an assumption as to the precise componentry used in the amp. I think we're not 100% confirmed on this piece yet, if I am not mistaken.

-Ed

However, Infineon's component portfolio doesn't offer much choice in this area. And a completely in-house development by SMSL is beyond my imagination, especially when you look at all the other Infineon-based amplifiers in their range, which are all limited to the standard layouts.

It would be interesting to see high-resolution photos of the PA200 board with component labeling; then we wouldn't have to rely solely on speculation about component similarity.

The AD825 shown in the SMSL image is also installed on the EVAL_AUDAMP24, and SMSL replaced the CS3310 with the pin-compatible PGA2311. Any similarities are therefore purely coincidental .

 

[Loba]

What do you mean standby?

V3 monos can be in standby mode

 

[Deleted member 72219]

V3 monos can be in standby mode

Are you talking about when they turn, “off,” using signal sensor?

-Ed