As AndrewT implied, that subject has been covered extensively, and has been "beaten to death", and beyond. I have posted links, I think, in this thread, to at least two large threads that investigate it rather completely, such as the thread started by Nico Ras about "Resevoir Capacitance Size", and the thread about "Paralleling Electrolytic and Film Capacitors". And there are many other shorter threads where it has also been discussed, in great detail.
Many of us spent a LARGE amount of time and did a LOT of in-depth work, for those threads, and can hardly bear even just the thought of repeating those efforts.
Dear Gootee,
I'm very sorry if I offended you.
Please don't get me wrong, I have read your explanations fully and with great interest.
I am a injection molding process specialist, its probably a knowledge not familiar on this forum but it has many similarities with what is discussed here
The injection molding process consists of many sub processes but the sum of all will result in the end product.
Specialists of the sub processes are very important and will often help to improve the final output of the final product but it also sometimes can produce blindness to see what is really needed to get a "perfect" end product.
I know quiet some cases where so called perfect theoretical perceptions of a sub process did no good to produce a good end product simply because its often impossible to predict the influence of it in the whole process.
My search is to find out what is the ideal situation for the complete amplifier as I have build it, to my opinion to accomplish this its essential to be able to measure the end product of the complete process and in the case of an amplifier its to be able to replace the subjective listening experience with an absolute way of measuring it.
In the replies in this thread it seems not possible to do this so for me it means it will always stay subjective and resulting in endless discussions based only on theories
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Thank you very much for your explanation.
I will read it carefully to try to understand the principles.
But let me say one thing in the meantime.
I remember a commercial integrated amp offered in two versions, one basic and one DT (i.e. Dual Transformers).
BASIC
DT
with the main difference being the presence of a second mains transformer.
All the reviewers agreed on the fact that the DT had a more robust and dynamic sound, in a word was the better amp.
I think that this also answers to my doubts.
I have remembered it only now with the discussion.
Instead of two one with twice the VA should have similar results i think.
Thanks a lot and kind regards,
gino
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Did you look?
I posted just yesterday about my experience from a few decades ago.
Provided the second transformer was not to separate the digital circuits PSU from the analogue circuits PSU, it would almost certainly be better to supply all the analogue circuits from one larger transformer with it's lower regulation and use as many secondary windings as is necessary for the individual circuits.
I wish that transformers were available cheaply that had four identical secondary windings.
Hi sorry i made a mistake 
I wanted to post this in the 3D about current bottlenecks.
It is completely off topic here.
By the way thanks a lot for the advice about a single bigger transformer with better regulation.
I do not think that the additional transformer was for digital circuits because the amp was completely analogue.
I think i should study the transformer issue much more.
I think i have found the real bottleneck i was looking for ..
Thanks again and kind regards,
gino
I wanted to post this in the 3D about current bottlenecks.
It is completely off topic here.
By the way thanks a lot for the advice about a single bigger transformer with better regulation.
I do not think that the additional transformer was for digital circuits because the amp was completely analogue.
I think i should study the transformer issue much more.
I think i have found the real bottleneck i was looking for ..
Thanks again and kind regards,
gino
It's about lower regulation that I suggest a minimum of 160VA for all Power Amplifiers, even little chipamps.
Normally a 50W+50W two channel amplifier would use a 100VA to 200VA transformer. That becomes 160VA to 200VA.
A single channel 50W could use a 50VA to 100VA. That becomes a 160VA for the single channel, even though it appears to be massively too big.
BTW, a 50+50W chipamp will work with a tiny 50VA transformer for normal domestic duty. It won't run hot. It won't sound great either.
Normally a 50W+50W two channel amplifier would use a 100VA to 200VA transformer. That becomes 160VA to 200VA.
A single channel 50W could use a 50VA to 100VA. That becomes a 160VA for the single channel, even though it appears to be massively too big.
BTW, a 50+50W chipamp will work with a tiny 50VA transformer for normal domestic duty. It won't run hot. It won't sound great either.
http://www.diyaudio.com/forums/chip-amps/252436-lm3886-pcb-vs-point-point-data-3.html#post3846783
Here is a clear demonstration on how simply getting the layout right will improve your amp. I have not found such measurements for amps with different PSU design. There are plenty of claims, no data to back it up. There are the believers, they have only faith in there designs and the non believers, they can test it but don't think it relevant.
Its quite optional when describing this situation to use the language of religion. There are those who experience better sound and those who think those who experience better sound are just imagining things. Of course there are yet others who don't think all the effort can be worthwhile.
Some of the experience of better sound can probably be explained by the 'IKEA effect' (I believe a phrase coined by Dan Ariely, a behavioural economist) - we get more satisfaction from stuff we build ourselves than stuff that we don't have any input to. Question is - what proportion can be accounted for by this?
WHAT'S YOUR BELIEF
what do you propose for a test ?
no matter what you show on any test or where to find improvements, there will be folks that reject the "science gurus" they have / follow the other ideas.
Its not really inability to measure rather it would take a lot of work to do it well and its just not as interesting as building and listening to amps. Those who love measurements and want everything quantified aren't generally the same people as those who love great sound.
Tomchr has build an almost ideal amp by measuring it, I cant help but love this approach. Now test it with different PSU configurations.
The basic variables are transformer and caps.
Cap test1 with single cap per rail. 1000, 2200, 4700 uF
Cap test2 repeat of test1 with the addition of local caps 1, 10 100, uF.
Test 3 repeat test2 with Load of 2, 4, 8 ohm.
This would give a good indication of what is happening.
I will do it myself when I have bought the equipment, learnt how to operate it and understand the results.
The basic variables are transformer and caps.
Cap test1 with single cap per rail. 1000, 2200, 4700 uF
Cap test2 repeat of test1 with the addition of local caps 1, 10 100, uF.
Test 3 repeat test2 with Load of 2, 4, 8 ohm.
This would give a good indication of what is happening.
I will do it myself when I have bought the equipment, learnt how to operate it and understand the results.
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yes those are many parts, but what kind of tests?
I plan on using 100uF 35 or 50V caps and I can find so many different cases and types just within those simple bounds. and esr over SRF varies over a big range
I recon it's not the # uF that counts but esr over what frequencies!
Im looking at http://www.chemi-con.co.jp/e/catalog/pdf/al-e/al-sepa-e/004-lead/al-kzm-e-140101.pdf
well my belief is below
The data sheet says and everything I know says you need a three cap PS rail solution
1) bulk caps, near the rectifiers,
2) midrange bypass electo / tantalum, near the chip pins
3) and tiny ceramic / film , at the chip pins
maybe if you like single driver speaker systems you might get lucky picking one cap solution like some believe
I plan on using 100uF 35 or 50V caps and I can find so many different cases and types just within those simple bounds. and esr over SRF varies over a big range
I recon it's not the # uF that counts but esr over what frequencies!
Im looking at http://www.chemi-con.co.jp/e/catalog/pdf/al-e/al-sepa-e/004-lead/al-kzm-e-140101.pdf
well my belief is below
The data sheet says and everything I know says you need a three cap PS rail solution
1) bulk caps, near the rectifiers,
2) midrange bypass electo / tantalum, near the chip pins
3) and tiny ceramic / film , at the chip pins
maybe if you like single driver speaker systems you might get lucky picking one cap solution like some believe
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You can use the data from all the "non science gurus" to help in reducing the amount of tests.
"I reckon it's not the # uF that counts but esr over what frequencies!" It's the capacitance and its parasitics and the length of the leads and the trace lengths. Some of it is fixed, some you can reduce by good design. As an example, what is the point of having the local caps close to the op-amp if the speaker return is at the other end of your PCB.
"I reckon it's not the # uF that counts but esr over what frequencies!" It's the capacitance and its parasitics and the length of the leads and the trace lengths. Some of it is fixed, some you can reduce by good design. As an example, what is the point of having the local caps close to the op-amp if the speaker return is at the other end of your PCB.
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Re chipamp local bypass is just keep the bad things from happening , they have nothing to do with speakers. you might need local bypassing on the bulk caps too.
IDK maybe only speaker testing / listening can truly satisfy , that's why I keep asking what testing
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He just cleaned up a marginal ptp build, only proving what many engineers of linear power knew before. eg keep loop areas small along w/ good decoupling practice. A wise man once said, return the noise (IMD) to whence it came.
the only results that matter is the final application circuit, eg your amps, your PCB layouts , with your unregulated supply, of which there are thousands built, all slightly different, some closer to data sheet results than others.
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