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Impressions: SMSL PA200 GAN FET Class-D Power Amp

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Ah, no need to discuss further, other than for consideration, and the PA200 is a nice example of material tech, via GaN (which allows/produces certain Electrical propertys), isn't it? A proposed consideration/suggestion is that is there a type of Conditioning occuring. To clarify, there are types of Conditioning (such as Annealing/Cryo/even Electrical tech), isn't there? The application of Annealing/Cryo is to change a materials property(s)/condition(s) to a desired Condition where one is a Heat/cool/etc and the other is a Cold/warm/etc, isn't it? A question/suggestion is, can Electrical Conditioning occur when applyed to materials (material tech).... a reasonable question/suggestion, isn't it?
Yes and no. One has to be careful when throwing around technical terms if one doesn't fully understand them. There are zillions of small things that affect the physical properties of electronics, even to the extent of producing measurable differences in the signal, but unless the differences are audible it doesn't matter. We don't obsess over the materials the printed circuit boards are made of, we don't obsess about how close to in-wall mains wiring our gear is, and we don't obsess about exact positioning of furniture in our living room.
 
I am never happy with my system, it's either too hot (300B and fosi v3 monos!), or not warm enough in mid range (v3 monos), muddy bass (300Bs) and both sucks power.

hence an upgrade to try to maintain similar performance while achieving less heat, using less power. The last closest one I had was SMSL AO300, before that AO200(not enough power to kick bass), NAD D3020 v2 (this was sweet sounding but hot!) , yamaha wxc-50 (this is dry), older Arcam (too polite, no bass) and Cambridge audio (hot and sounds crass) class AB mid range early 2000s amps. which are objectively lower performance in measurements and audibly.

the last frontier to cross was my wife who is the daughter of an audioman in the media industry who had done recording in the music industry, built his own speakers (15" drivers!) and does manual crossover of his speakers. She has trained golden ears who will tell me immediately if the amp is rubbish or too harsh. Sometimes I will just swap in new amps without telling her and ask how's the music hence how a Class A jeff rowland amp got retired to my office due to the unbearable brightness to her. I had secretly turned them on a few times but her mood will immediately turn for the worse asking me to turn off the music citing the music being extremely irritating.
My wife hated it when I put on music. And still she does not like the Genelec active system with AK4191/AK4499EX layout which I really enjoy in the morning.

It's only after introducing r2r non oversampling and tube pre amp with purifi she doesn't walk away from the couch anymore. But perhaps a cassette tape could do the same... And is much cheaper.

I think there's something in the digital domain other than linear respones with does something to our brains but I am not an engineer so i can't give you any useful advice. But to come back to the subject, of the SMSL PA200, this might be the right one for you at this moment, at least with the anniversary ali pricings.
 
I am never happy with my system, it's either too hot (300B and fosi v3 monos!), or not warm enough in mid range (v3 monos), muddy bass (300Bs) and both sucks power.

hence an upgrade to try to maintain similar performance while achieving less heat, using less power. The last closest one I had was SMSL AO300, before that AO200(not enough power to kick bass), NAD D3020 v2 (this was sweet sounding but hot!) , yamaha wxc-50 (this is dry), older Arcam (too polite, no bass) and Cambridge audio (hot and sounds crass) class AB mid range early 2000s amps. which are objectively lower performance in measurements and audibly.

the last frontier to cross was my wife who is the daughter of an audioman in the media industry who had done recording in the music industry, built his own speakers (15" drivers!) and does manual crossover of his speakers. She has trained golden ears who will tell me immediately if the amp is rubbish or too harsh. Sometimes I will just swap in new amps without telling her and ask how's the music hence how a Class A jeff rowland amp got retired to my office due to the unbearable brightness to her. I had secretly turned them on a few times but her mood will immediately turn for the worse asking me to turn off the music citing the music being extremely irritating.
What exactly do you mean by power consumption? How much power should an amplifier consume when idle (not in standby)?

The AO300 and AO200 are completely different amplifiers; the AO300 and AO200 MKII should be very similar.
May I ask what your wife said about the AO300?
 
I think there's something in the digital domain other than linear respones with does something to our brains but I am not an engineer so i can't give you any useful advice.
Are you aware of the fact that pretty much all mainstream music recorded since the mid-1980's have passed a digital stage in the vinyl lathe in the cutting process? Of course almost all music is recorded in digital these days...
 
Are you aware of the fact that pretty much all mainstream music recorded since the mid-1980's have passed a digital stage in the vinyl lathe in the cutting process? Of course almost all music is recorded in digital these days...
Yes I know. I have done music production myself. I have no experience with vinyl so I don't know anything about it.

And when technology and filtering in the recording studios finally started to get better they distroyed the human voice with auto tuning...Sorry, i am getting old..
 
And when technology and filtering in the recording studios finally started to get better they distroyed the human voice with auto tuning...Sorry, i am getting old..
Indeed. On the other hand, even older farts than me decry the invention of synthesizers, samplers and drum machines. I guess it isn't so much about the tools, but how they are abused. Let's hope the excessive autotuning is a passing fad.
 
My wife hated it when I put on music. And still she does not like the Genelec active system with AK4191/AK4499EX layout which I really enjoy in the morning.

It's only after introducing r2r non oversampling and tube pre amp with purifi she doesn't walk away from the couch anymore. But perhaps a cassette tape could do the same... And is much cheaper.

I think there's something in the digital domain other than linear respones with does something to our brains but I am not an engineer so i can't give you any useful advice. But to come back to the subject, of the SMSL PA200, this might be the right one for you at this moment, at least with the anniversary ali pricings.
haha, that's sad. She will be mad if she sees the bill for Genelec?

oh R2R with tube is warmish. My wife also likes the 300Bs. Pleasant distortions, terrible measurements "performance" I'm sure. I personally prefer 300B tubes in the morning when the mind is more alert and Class D or A at night when the mind is more tired.

I certainly hope so PA200 cuts it
 
Yes I know. I have done music production myself. I have no experience with vinyl so I don't know anything about it.

And when technology and filtering in the recording studios finally started to get better they distroyed the human voice with auto tuning...Sorry, i am getting old..
Indeed. On the other hand, even older farts than me decry the invention of synthesizers, samplers and drum machines. I guess it isn't so much about the tools, but how they are abused. Let's hope the excessive autotuning is a passing fad.
But that also depends heavily on the label.
When I switch from the usual mainstream streaming to recordings from, for example, Chesky Records, Ruf Records, 105Music, Inakustik, Sound Liaison, Nagra, etc., it sometimes feels like a slap in the face.
 
oh R2R with tube is warmish. My wife also likes the 300Bs. Pleasant distortions, terrible measurements "performance" I'm sure. I personally prefer 300B tubes in the morning when the mind is more alert and Class D or A at night when the mind is more tired.
Fortunately modern DSP gives us the possibility of both in the same system. TAP TubeWarmth
 
My wife hated it when I put on music. And still she does not like the Genelec active system with AK4191/AK4499EX layout which I really enjoy in the morning.

It's only after introducing r2r non oversampling and tube pre amp with purifi she doesn't walk away from the couch anymore. But perhaps a cassette tape could do the same... And is much cheaper.

I think there's something in the digital domain other than linear respones with does something to our brains but I am not an engineer so i can't give you any useful advice. But to come back to the subject, of the SMSL PA200, this might be the right one for you at this moment, at least with the anniversary ali pricings.
haha, that's sad. She will be mad if she sees the bill for Genelec?

oh R2R with tube is warmish. My wife also likes the 300Bs. Pleasant distortions, terrible measurements "performance" I'm sure. I personally prefer 300B tubes in the morning when the mind is more alert and Class D or A at night when the mind is more tired.

I think it's more on the alertness of mind which affects how we perceived music. Equipment is never tired hence the most accurate to judge performance.
 
The third advice for me personally (after my subjective experience with the I2s cable) was to start listening to these 'time domain smearing' stories some people are telling online.

There is always more to look into, and so much to learn. For those of us who aren't engineers, one of the more accessible aspects of this hobby is the area of psychoacoustics, which is almost completely ignored by the industry propaganda machine.

I was surprised to find that a number of components I was quite sure had various 'sound signatures,' suddenly sounded exactly the same to me once I matched their output levels and tested myself where I couldn't peek (blind).

No amount of reading or questions could have made the impression on me that first controlled test did. My bet is that if you compared your I2S cable with any other competent digital cable (while using basic controls) you aren't going to be able to tell the difference. I don't believe there is even a standard for an external I2S cable, as it was never really intended to leave the box. That's a good example of the propaganda machine at work. A completely useless, inconvenient 'feature' sold as the next best thing. Here, buy some cables.

You are clearly asking questions in good faith and looking to add to your knowledge base, and you've come to the right place for that. The more you can fearlessly put your preconceptions to the test, the more you stand to gain.
 
The third advice for me personally (after my subjective experience with the I2s cable) was to start listening to these 'time domain smearing' stories some people are telling online.
The technical term for "time domain smearing" is jitter. Measuring jitter is something many of us are very familiar with, but the big debate is what amount of jitter is audible.
 
The technical term for "time domain smearing" is jitter. Measuring jitter is something many of us are very familiar with, but the big debate is what amount of jitter is audible.
I used to own a wiim ultra which I then sold and replaced with wiim pro for my desktop setup but found that it sounded different. Someone told me it was due to jitter and if that is true, then it is the cohesiveness of the music that sounds different to me. Very subjective for sure.
 
I used to own a wiim ultra which I then sold and replaced with wiim pro for my desktop setup but found that it sounded different. Someone told me it was due to jitter and if that is true, then it is the cohesiveness of the music that sounds different to me. Very subjective for sure.
I would need a bit more evidence than just "someone told me", but then again, I would also need a double blind test to believe it sounded different. :)
 
The technical term for "time domain smearing" is jitter. Measuring jitter is something many of us are very familiar with, but the big debate is what amount of jitter is audible.
May I put another of my preconceptions to the test?
again I am not an expert and not an engineer but after 30 years of listening I would like to find some technical insight here.

I never invested in expensive cables, (i just buy from a studio brand with the right 110 ohm or 75 ohms and most of the time I choose AES/EBU)
but with this I2s thing I really got lost on the way. It might be in a blind test my myths will break as well, but for some reason I keep hearing a difference. And i tried many hdmi cables all with quality. I always checked the I2s protocols on both sides would match.

so according to this table 'time domain smearing' is a deterministic phenomenon tied to the systematic characteristics whereas 'jitter' (deterministic or random) refers also to this random aspect.

so in my brain to keep some logic I made 2 hypothesis.

1. there's a difference in 'elektromagnatic' traveling around the silver vs copper
2. there's a better signalling of the clock's info through the I2s compared to hdmi, for whatever reason
3. the HDMI cable seller has a 90& profit margin and is actually of low quality material.
 

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1. there's a difference in 'elektromagnatic' traveling around the silver vs copper
No.
2. there's a better signalling of the clock's info through the I2s compared to hdmi, for whatever reason
The reason is that they are very different protocols, both electrically and on the signalling level. They were designed for very different purposes.
3. the HDMI cable seller has a 90& profit margin and is actually of low quality material.
Unless the cables are really bad, it should not matter. Most modern DACs reclock the data anyway.

Jitter can be random or cyclical ("systematic).

Don't believe the table you included - it was done by someone who either doesn't understand digital signalling or wants to give a false picture. You should see the signal edges coming out of a transatlantic fibre optic cable - despite the rather "soft" edge we transmit gigabits of data per second without errors or issues.
 
Thank you, is the Lars, Lars Clausen of the LC Audio (pre 2000 days, edit: before Hypex and I also remember their creations/implementations)? If yes, ah, I remember his DIY creations/implementations (and used them), quite well, how about that. I also remember that he had decided to give more attention/interest to wave/wind tech (edit: perhaps, also and because at that time, Hypex DIY classD implementations were improving and beginning to surpass the LC Audio classD implementations (well done to Hypex, especially because they have continued to improve) :=)

If you still know/remember the link, of that Bruno and Lars discussion, do you mind posting the link in this thread, thank you....

Lars Risbo.

I have posted it on this site previously. Try the search function. I don't have it at hand.
 


No those aren't the links to the interview I mentioned but the first link above does summarize in rather layman's terms the reason GaN fets aren't much more than a marketing ploy in most cases when it comes to class d amps. Here is the relevant section (credit to the author, Bruno Putzeys):

"The Revolution that is, and isn’t GaN

New materials always get audiophiles’ hearts racing, much more so than strides in engineering fundamentals. Where would the loudspeaker market be without the perennial parade of new cone materials? They’d be forced to make fundamental improvements, which many people in the industry find challenging. Something similar is happening on the fringes of class D.


Let’s get this out of the way first: yes, GaN FETs are faster and easier to use than silicon. But at home audio power levels, the gap is narrow. 150V GaN FETs are about twice as fast as their much cheaper silicon counterparts. This means that if you drop GaN FETs into an existing class D amplifier, you can only hope to improve distortion by a factor of 2 or so.


But what’s a single-digit reduction, considering that in the past years, we’ve reduced distortion several thousand times using nothing but an extra op amp and a few passives (and, admittedly, reams of formulae)? Furthermore, that reduction goes across the board: distortion from switch timing, output inductor nonlinearity, and power supply noise are all impacted. Whereas the much-vaunted GaN FET improves timing distortion alone, which isn’t even that audible.


This explains why the established players haven’t jumped on the bandwagon. Head over to my competitors at ICE to read their excellent take8. The short rundown is: “When you know what you’re doing, GaN doesn’t really move the needle and is a waste of money. We’ll do GaN for you if you think it helps you sell products, but don’t expect any enthusiasm from us”. Amen.


By contrast, it’s been enthusiastically embraced as a band-aid and buzzword by parties who have little to bring to the table in terms of intelligent design or audio performance. The actual circuits in most commercial GaN-based amplifiers are nothing we wouldn’t have recognized 20 years ago. Often, they are basic open-loop schoolbook amplifiers, with lack of feedback ludicrously a claimed benefit.


This is sad because GaN is a breakthrough, just not one that’s relevant for Hi-Fi and home cinema amps. This changes markedly, and spectacularly so, once you pass 200V. 200V silicon FETs are significantly slower than 150V ones. By contrast, there’s not much of a speed gap between 150V and 600V GaN FETs. While GaN isn’t about to change what audio performance is available, it’s certainly going to change what power level this performance is available at. I can assure you, anything north of a kilowatt, I’d use GaN. Not because it’s magic, but because it’s practical. That’s something to look forward to. Imagine a touring amplifier with audiophile performance…"
 
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@EddNog, thank you for organiseing the ASR measurements with @amirm. Thank you @amirm, we (all) look forward to the ASR measurements (when able), even without Anticipation Bias, don't we (all) :=)
 
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