Yes I know. This is how the Internet should be. A bunch of people sharing their love, insights and enthusiasm for a common cause like building your own amplifiers motivated by each-other and an inspirational guide. I know compared to a lot of social platforms this one is a safe haven with friendly and helpful guys.
I mentioned this now already multiple times before. But it seems just completely ignored.
If they want to stay compliant to the EU regulations, it's not a question to go for a SMPS, but rather a must.
I use SMPS now (high quality) for DIY power amps because it reduces weight, prices, time to build etc. It also eliminates problems with 50/100 Hz hum noise.
Even preamps seem happy with SMPS if a little attention is made to eliminate HF/RF noise.
I don't think the end consumer will accept SMPS in High-End products just because it is a SMPS (audiophiles are very "religious").
I also think many thinks that SMPS are not as reliable as linear PSU's.
Are Class-D amps more "un-realiable" than the others? .....I don't know....
Regarding EU compliance etc.......I have no idea.
I don't know who is selling Pass Labs amps in Denmark if any?), but I found this large mono block amp which uses a 1600 VA trafo so a very large linear PSU.
I assume it is EU-compliant.......but who knows? 🙂
https://high-performance.dk/ps-audio-perfectwave-bhk-m600-mono-power
Even preamps seem happy with SMPS if a little attention is made to eliminate HF/RF noise.
I don't think the end consumer will accept SMPS in High-End products just because it is a SMPS (audiophiles are very "religious").
I also think many thinks that SMPS are not as reliable as linear PSU's.
Are Class-D amps more "un-realiable" than the others? .....I don't know....
Regarding EU compliance etc.......I have no idea.
I don't know who is selling Pass Labs amps in Denmark if any?), but I found this large mono block amp which uses a 1600 VA trafo so a very large linear PSU.
I assume it is EU-compliant.......but who knows? 🙂
https://high-performance.dk/ps-audio-perfectwave-bhk-m600-mono-power
This doesn't make sense to me.... at so many levels.
With class A amp, the SMPS has 0 benefits. All the heat comes from the output stage biased in class A.
Furthermore, the SMPS would just spit a lot of HF rubbish back to the mains supply... so no other sensitive equipment (pre-amps / DACs / turntables) can be plugged into the same power outlet. They are nasty things those high-power SMPS...
Also, I believe that, due to the regulating nature of the SMPS, the heat dissipation would be greater in the {SMPS + class A output stage} vs. {conventional power supply + the same class A output stage}.
I spent 6 months trying to get various high-quality SMPSs to outperform my liner power supply, powering NUC11 which I use as a streamer.
The SMPS can sound nice, extended... but it can't come close to the liner power supply I built. There is simply no comparison. The LPS sounds so much more natural and authoritative.
Of course, I may have done many things wrong when I tried to optimise the SMPSs, and a few things right when I built the LPS.... but it was all unintentional. In other words, I tried really hard to favour SMPS in this application (powering up my NUC).
Yeah... because it doesn't have the SMPS inside, so no need to combat RF rubbish going back to mains...
When I build ZM's "Lazy Bush" I will make a building thread and there will also be a bit info about SMPS as I have ordered these and the company will optimize them for my use. They asked for the usage as I ordered 2 x 2 kW types. Then we had a little discussion and as I only need 3-4 A they will optimize them for that. I found out they knew more about SMPS theory than I do 🙂
Regarding mains......then all commercial equipment uses SMPS today (TV's etc.) I think in EU there is a requirement that phone charger adaptors must be SMPS to not waste energy. They are very small SMPS but there are so many connected.......but these must also be EU-compliant.
As well as @Extreme_Boky That has given a couple of posts back.
We are not talking about the audio performance here, but regulations that has to do with harmonics and other stuff that devices create on the mains net. Those are two completely different things.
(I know soms people thing a device is only 100% tailored for audio performance, but that is just not the reality)
Oh btw, this doesn't have anything to do with RF rubbish, but the power factor (as well as the involved harmonics).
ANY audio device has to comply with this.
I have a very hard time believing that one can get away with this with a linear power supply these days.
Even for a Class-A amplifier. But therefor I have asked multiple times now if there is any proof of being compliant with IEC/EN61000-3-2.
Just one CE sticker doesn't proof this.
So in other words, these days it's very hard to be compliant without an active PFC circuit in your device.
Which is often part of a SMPS.
Sure, that can also be done with a linear power supply, or sometimes can be done with a passive PFC circuit, but both are extremely uncommon.
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Sorry for delay. Was travelling.
Seems a bit late now since you may already know the answers from more knowledgeable people. Still haven't had time to read your report, but I'll still guess even at the risk of being wrong.
- Lower mains voltage - seems likely. Provided some suggested calcs for demonstration in another post. Nelson further offered direct confirmation re: what might be expected with a 10% reduction in mains voltage.
- Altered bias settings - definitely
- Different methodology for measuring 1% distortion
- Different 1% distortion spec perhaps (THD / THD +N)?
- Variance 'stacking' -- This one is 5% 'high', this one is 5% 'low' => 10% deviation. We do repetitions in my field to help eliminate.
Again... all guesses, and as previously stated, I'm often wrong. Sadly, this seems to have devolved a bit more. I hope I didn't contribute to that. Again, I hope you determine what you're looking for re: the differences in measurement technique and results. If anything, many people may learn just how 'easy' it can be to have such vast differences in reported performance with just a few 'seemingly minor' changes to operating conditions and measurement techniques.
I'll be watching from the bleachers now. I type too much anyway.
I fibbed unintentionally re: last post and watching from the bleachers. I'm still curious about this.
I'm still wondering how a device rated for 32A output fits into the 3-2 standard, but as admitted, I don't know.
I took the time to read the attached. I admit to reading it very quickly and in an area where I could not focus well, but will give it a more thorough read as time allows. I may have completely misinterpreted the premise behind the standard and associated test methods, but I really don't see how this test / standard relates at all to the matter at hand of measuring a rated power level at 1% distortion.
With that said, it may be a relevant standard even if I don't understand how it applies to this particular product.
Even stipulating that the standard applies to a 600.5, I don't see why the compliance is being questioned. I don't see any measurements that have been posted or alluded to that would indicate even the potential for non-compliance.
Once again, my intention is not to question with malice or indicate that someone is 'wrong'. I am genuinely curious, I looked for an answer myself, and I am failing to understand. That could be in large part because I am completely misinterpreting both the purpose for the compliance standard and how it's intended to be measured.
Thanks for any insight you're willing to offer. You seem to be an expert in the matter.
Now back to the bleachers.
I still don't get it. What do you mean by "...has to do with harmonics and other stuff...". Referring to a IEC document that costs a few hundred bucks to look at is not helpful. Can you be more specific about what exactly is (or might be) wrong with using linear power supplies in the EU?
At 8 Ohms I pressume? What's the issue then? Is that the red curve doesn't reach the 600 Watts and the reference does.
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