Impressions: SMSL PA200 GAN FET Class-D Power Amp

[Tlow98]

By the way, for full disclosure, the two other amps that I was originally considering before I bought the PA200s were Schiit Vidar 2 (one unit, for now) or pair of Outlaw Model 2220 monoblocs (came EXTREMELY CLOSE to pulling the trigger on a pair of these, open-box/refurb). Both of those amps actually are slightly worse SINAD/THD+N than even the PA200.

-Ed

I was also shopping the Vidar 2. Still may get one. Would like to know what another flavor is like.

 

[KL....]

Nice writeup, glad that you really like this amp :=)
What are your impressions between bridged/mono and unbridged/stereo? Any negatives?

I did not notice a specific performance difference at lower volumes, despite the potential (small) hit to SINAD for bridging. At high volumes, the speakers really sing when driven in bridged mono mode!

@EddNog, with playtime, are your impressions still the same?

Couple of negatives to consider....

• for mono/bridged mode, only XLR input can be used, Right +/positive binding post (which is good) but the Left +/positive binding post has been used as -/negative instead of the Right -/negative or even Left -/negative binding post?
• accepts RCA for stereo but RCA cannot be used for mono/bridged mode. For mono/bridged mode, it would have been nice if Right RCA input and Right +/positive and -/negative Binding Posts, were available.
• the RCA sockets are recessed (it appears so or is it an optical illusion, please confirm?), if the chassis opening is not large enough, this could make it difficult for connecting RCA plugs with Locking Barrels/Housings or RCA plugs with forward extended Housings because they may not fit through the chassis opening or the barrel/housing could touch the chassis, or simply large RCA plugs or ....

 

[Deleted member 72219]

@EddNog, with playtime, are your impressions still the same?

Couple of negatives to consider....

• for mono/bridged mode, only XLR input can be used, Right +/positive binding post (which is good) but the Left +/positive binding post has been used as -/negative instead of the Right -/negative or even Left -/negative binding post?
• accepts RCA for stereo but RCA cannot be used for mono/bridged mode. For mono/bridged mode, it would have been nice if Right RCA input and Right +/positive and -/negative Binding Posts, were available.
• the RCA sockets are recessed (it appears so or is it an optical illusion, please confirm?), if the chassis opening is not large enough, this could make it difficult for connecting RCA plugs with Locking Barrels/Housings or RCA plugs with forward extended Housings because they may not fit through the chassis opening or the barrel/housing could touch the chassis, or simply large RCA plugs or ....

View attachment 434405

Correct, in mono mode, the left positive post becomes the negative post

Correct, it cannot provide true mono power with single-ended input because it relies on the opposite differential signals from a true balanced line to feed the opposite half bridges (similar to Schiit Vidar or Aegir amps). Although I suppose it may be possible to utilize an op-amp to convert a single-ended signal into a differential signal to achieve this, but they didn’t choose to include this capability.

The RCA sockets aren’t recessed:

-Ed

 

[drmevo]

Not to stray too far off topic, but curious what your high and low pass settings are with this set up @EddNog?

 

[Deleted member 72219]

Not to stray too far off topic, but curious what your high and low pass settings are with this set up @EddNog?

As I only have one subwoofer, I leave it at the default setting on the Anti-Mode X2D, which is at 80Hz. I would run it higher if I had a second SB-3000, but I neither want to spend the money for one nor have to find the space for it. That’s not even to mention the cost and effort to replace my Anti-Mode X2D with a solution that can handle stereo subwoofers (such as a MiniDSP, which is significantly more complicated to use than the, “one-button-press,” Anti-Mode).

-Ed

 

[would]

Thanks for your Impressions, @EddNog

I got mine yesterday, but am curious about the "temperature".

When it's on it's warm, not hot. No problem at all.

BUT: it's the same temperature when it's in standby. Can you confirm that? The red standby lights (speaker connectors) look cool btw

 

[Deleted member 72219]

Thanks for your Impressions, @EddNog

I got mine yesterday, but am curious about the "temperature".

When it's on it's warm, not hot. No problem at all.

BUT: it's the same temperature when it's in standby. Can you confirm that? The red standby lights (speaker connectors) look cool btw

By standby do you mean on, but not playing? Or do you mean when it’s not active and the small red LED is on in the front?

-Ed

 

[Deleted member 72219]

Thanks for your Impressions, @EddNog

I got mine yesterday, but am curious about the "temperature".

When it's on it's warm, not hot. No problem at all.

BUT: it's the same temperature when it's in standby. Can you confirm that? The red standby lights (speaker connectors) look cool btw

I left my amps off/standby (red light on the front is lit) overnight and just checked and I agree that the amp is still mildly warm. Good thing I ordered that trigger-activated power strip!

-Ed

 

[would]

Thanks for checking!

P.s. I meant Stand-By. Red led on front is on.

 

[Tlow98]

Question - how much of the power needs of your system is caused by the Anti-Mode? I’ve yet to try a DSP, but want to.

Have you tried removing it with your different sets of amps? Wondering about headroom, etc. You have a similar-ish setup and use case as mine. And finally, would you ever go without DSP or is too impactful on your listening to consider that?

Any thoughts helpful. Anything… I’m. So. New.

 

[Deleted member 72219]

Question - how much of the power needs of your system is caused by the Anti-Mode? I’ve yet to try a DSP, but want to.

Have you tried removing it with your different sets of amps? Wondering about headroom, etc. You have a similar-ish setup and use case as mine. And finally, would you ever go without DSP or is too impactful on your listening to consider that?

Any thoughts helpful. Anything… I’m. So. New.

The DSP actually doesn’t suck up a whole lot of power per se—this assumes listening with a flat response. What sucks up a lot of gain (and, as an indirect result, power) is my use of tone control to simulate a Harman curve, my preferred overall tonal signature. I use the highly adjustable tone controls in the Anti-Mode X2D to simulate a Harman curve, and the way that this works is to apply a preamp volume reduction so that boosting low and lower mid frequencies won’t cause distortion or clipping. How do I know this? Because the more I boost the bass, the lower the maximum volume is on the Anti-Mode. Maximum volume with a flat curve is 0. I have the bass turned up enough to simulate a Harman curve and because of this, the maximum volume setting I can go is -7. There is a pretty substantial difference in volume between 0 and -7 settings on the Anti-Mode. The only real way to compensate for this is to have a power amplifier with sufficient gain, more so with low-sensitivity speakers.

The LS50 Metas are neither super-sensitive nor super not sensitive. I am still able to hit higher than comfortable listening levels before maxing out my volume on the lowest volume tracks in my test list (specifically used for testing is All-Star Percussion Ensemble’s rendition of Carmen—this track needs me to turn volume WAY WAY higher than normal, and I always flip the WiiM to repeat track before using this track to test because I am afraid of absent-mindedly forgetting to stop the music when the track ends and then suddenly playing a much more normal volume track with the volume jacked way the hell up!).

I haven’t tried removing DSP. The reason for this is because I am limited in how/where I can place my speakers/system in my home, and the room correction is absolutely critical for this system to sound as good as it does. It’s placed asymmetrically in a room with a ton of soft/absorbent furniture/surfaces and full carpeting. I would venture to say my setup demands room correction much more than average. I also am not willing to spend money on room treatments as this room is definitely not going to be the permanent home for the system—once my 7- and 5-year-old sons are a few years older, I’m moving all this to the much more symmetrical layout in our formal living room with hardwood floors (it’s currently set up sideways on one end of the family room right now).

-Ed

 

[OdiusEX]

The DSP actually doesn’t suck up a whole lot of power per se—this assumes listening with a flat response. What sucks up a lot of gain (and, as an indirect result, power) is my use of tone control to simulate a Harman curve, my preferred overall tonal signature. I use the highly adjustable tone controls in the Anti-Mode X2D to simulate a Harman curve, and the way that this works is to apply a preamp volume reduction so that boosting low and lower mid frequencies won’t cause distortion or clipping. How do I know this? Because the more I boost the bass, the lower the maximum volume is on the Anti-Mode. Maximum volume with a flat curve is 0. I have the bass turned up enough to simulate a Harman curve and because of this, the maximum volume setting I can go is -7. There is a pretty substantial difference in volume between 0 and -7 settings on the Anti-Mode. The only real way to compensate for this is to have a power amplifier with sufficient gain, more so with low-sensitivity speakers.

The LS50 Metas are neither super-sensitive nor super not sensitive. I am still able to hit higher than comfortable listening levels before maxing out my volume on the lowest volume tracks in my test list (specifically used for testing is All-Star Percussion Ensemble’s rendition of Carmen—this track needs me to turn volume WAY WAY higher than normal, and I always flip the WiiM to repeat track before using this track to test because I am afraid of absent-mindedly forgetting to stop the music when the track ends and then suddenly playing a much more normal volume track with the volume jacked way the hell up!).

I haven’t tried removing DSP. The reason for this is because I am limited in how/where I can place my speakers/system in my home, and the room correction is absolutely critical for this system to sound as good as it does. It’s placed asymmetrically in a room with a ton of soft/absorbent furniture/surfaces and full carpeting. I would venture to say my setup demands room correction much more than average. I also am not willing to spend money on room treatments as this room is definitely not going to be the permanent home for the system—once my 7- and 5-year-old sons are a few years older, I’m moving all this to the much more symmetrical layout in our formal living room with hardwood floors (it’s currently set up sideways on one end of the family room right now).

-Ed

TY EddNog, tremendous posts and pictures. The PA200s seem like cutting edge tech at cut-rate prices...and yes *you* took all the risks. I'm very happy you've gotten next level performance. All said, I'm unclear why you haven't rolled the op amps yet. (justkidding)

 

[Tlow98]

The DSP actually doesn’t suck up a whole lot of power per se—this assumes listening with a flat response. What sucks up a lot of gain (and, as an indirect result, power) is my use of tone control to simulate a Harman curve, my preferred overall tonal signature. I use the highly adjustable tone controls in the Anti-Mode X2D to simulate a Harman curve, and the way that this works is to apply a preamp volume reduction so that boosting low and lower mid frequencies won’t cause distortion or clipping. How do I know this? Because the more I boost the bass, the lower the maximum volume is on the Anti-Mode. Maximum volume with a flat curve is 0. I have the bass turned up enough to simulate a Harman curve and because of this, the maximum volume setting I can go is -7. There is a pretty substantial difference in volume between 0 and -7 settings on the Anti-Mode. The only real way to compensate for this is to have a power amplifier with sufficient gain, more so with low-sensitivity speakers.

The LS50 Metas are neither super-sensitive nor super not sensitive. I am still able to hit higher than comfortable listening levels before maxing out my volume on the lowest volume tracks in my test list (specifically used for testing is All-Star Percussion Ensemble’s rendition of Carmen—this track needs me to turn volume WAY WAY higher than normal, and I always flip the WiiM to repeat track before using this track to test because I am afraid of absent-mindedly forgetting to stop the music when the track ends and then suddenly playing a much more normal volume track with the volume jacked way the hell up!).

I haven’t tried removing DSP. The reason for this is because I am limited in how/where I can place my speakers/system in my home, and the room correction is absolutely critical for this system to sound as good as it does. It’s placed asymmetrically in a room with a ton of soft/absorbent furniture/surfaces and full carpeting. I would venture to say my setup demands room correction much more than average. I also am not willing to spend money on room treatments as this room is definitely not going to be the permanent home for the system—once my 7- and 5-year-old sons are a few years older, I’m moving all this to the much more symmetrical layout in our formal living room with hardwood floors (it’s currently set up sideways on one end of the family room right now).

-Ed

Fantastic, thank you. This internal monologue type post if very helpful for me as I think about my next steps. Would love to listen to some ls50s… one day!

 

[KL....]

Correct, in mono mode, the left positive post becomes the negative post

Correct, it cannot provide true mono power with single-ended input because it relies on the opposite differential signals from a true balanced line to feed the opposite half bridges (similar to Schiit Vidar or Aegir amps). Although I suppose it may be possible to utilize an op-amp to convert a single-ended signal into a differential signal to achieve this, but they didn’t choose to include this capability.

The RCA sockets aren’t recessed:

-Ed

Thank you, actually, the simplest solution would be to simply include a Mono RCA socket, alongside the Mono XLR socket, and appropriate circuitry (such as op-amp to convert a single-ended signal into a differential signal, switch for selection, etc). Then if you were using RCA interconnects with the pa200 for stereo, which you must do, then decided to purchase/try another one to use them in mono for stereo, well, you could use your existing RCA interconnects for connection without needing to purchase a pair of XLR interconnects.... wouldn't it? This would also allow an apples/apples comparison with using your existing RCA interconnects then later, when ready, you could purchase/try a pair of XLR interconnects for comparison. But it doesn't allow this approach but it would be nice.... wouldn't it?

 

[Deleted member 72219]

Thank you, actually, the simplest solution would be to simply include a Mono RCA socket, alongside the Mono XLR socket, and appropriate circuitry (such as op-amp to convert a single-ended signal into a differential signal, switch for selection, etc). Then if you were using RCA interconnects with the pa200 for stereo, which you must do, then decided to purchase/try another one to use them in mono for stereo, well, you could use your existing RCA interconnects for connection without needing to purchase a pair of XLR interconnects.... wouldn't it? This would also allow an apples/apples comparison with using your existing RCA interconnects then later, when ready, you could purchase/try a pair of XLR interconnects for comparison. But it doesn't allow this approach but it would be nice.... wouldn't it?

I guess it would. RCA is of no personal concern to me anyway, but I can see how that might be useful for others.

-Ed

 

[KL....]

Thank you, actually, the simplest solution would be to simply include a Mono RCA socket, alongside the Mono XLR socket, and appropriate circuitry (such as op-amp to convert a single-ended signal into a differential signal, switch for selection, etc). Then if you were using RCA interconnects with the pa200 for stereo, which you must do, then decided to purchase/try another one to use them in mono for stereo, well, you could use your existing RCA interconnects for connection without needing to purchase a pair of XLR interconnects.... wouldn't it? This would also allow an apples/apples comparison with using your existing RCA interconnects then later, when ready, you could purchase/try a pair of XLR interconnects for comparison. But it doesn't allow this approach but it would be nice.... wouldn't it?

I guess it would. RCA is of no personal concern to me anyway, but I can see how that might be useful for others.

-Ed

Thank you, yes, the versatility would be nice and if it was available it would be nice to have amirm test/measure it and it other input features.... wouldn't it :=)

 

[Deleted member 72219]

Thank you, yes, the versatility would be nice and if it was available it would be nice to have amirm test/measure it and it other input features.... wouldn't it :=)

I would be happy to see him test it of course, if anything so that these amps can get a little more exposure than they currently get. Guessing it won’t set the world on fire with its (nowadays) mediocre SINAD. Some people (like myself) may not care, especially some who care more about other things (aesthetics, power output, quality of components such as the binding posts, not having external power supplies, etc.).

-Ed

 

[Matt_Holland]

I would be happy to see him test it of course, if anything so that these amps can get a little more exposure than they currently get. Guessing it won’t set the world on fire with its (nowadays) mediocre SINAD. Some people (like myself) may not care, especially some who care more about other things (aesthetics, power output, quality of components such as the binding posts, not having external power supplies, etc.).

-Ed

SMSL’s 1KHz THD+N graph shows approx 0.004% at 5W in bridge mode which is -88dB SINAD.

Bandwidth looks very good. Power output is excellent.

You say this amp is delivering something special subjectively which intrigues me.

 

[goryu]

Does this amp have post filter feedback or is it open loop?

 

[Deleted member 72219]

Does this amp have post filter feedback or is it open loop?

They don't state, but the bandwidth is excellent, with frequency response solidly flat through the entire audible band.

-Ed