Is it possible for a power supply to affect sound quality?

[StephenJK]

19 hours ago, sandyk said:

 Try telling that to Alex C , E.E. John Swenson and many others, especially the majority of the posters in this thread

 .https://audiophilestyle.com/forums/topic/30376-a-novel-way-to-massively-improve-the-sq-of-computer-audio-streaming/#comments

 I did exactly what you demanded recently for a well qualified participant in this thread. via a PM.

 In this case it was powering a USB memory stick instead of using the PC's crappy SMPS +5V USB power.

https://audiophilestyle.com/forums/topic/54909-usb-audio-transmission-isn’t-bit-true/page/18/#comments

 

I would offer you some examples, but given an attitude like yours I doubt that your equipment is likely to be good enough to either see or hear the differences anyway.

What type of equipment I have and whether it's good enough would be my concern, not yours - and certainly has little to do with the conversation.  I think low level insults are best left aside, wouldn't you agree?

[John Dyson]

On 6/19/2020 at 3:38 PM, SJK said:

SPICE is a great tool, but my question is are we really overthinking this whole thing?  

 

A full wave bridge, basic filter network and you get a DC power supply with a bit of ripple.  No electronics, no chips, old school power.  It works, and it works well.  All of the comments to my question are with a solution that involves some type of custom designed circuit that in a complex way does the same thing.  

 

And, the question still stands.  That old school rectifier/filter with a bit of ripple, does it sound better or worse than a boutique solution?

 

Sounds like we need to have a showdown, pardner.  

The major thing, whether or not you use subsequent linear regulation, depending on application, is perhaps a shielded transformer (missing on the schematic), and RF choke.  That can help all kinds of little noise issues that can leak through, can even bypass good regulation.   Also, always use a RF choke on the mains, again because of noise leakage issues.   Of course, grounding layout is missing on practically all power supply schematics, but layout IS part of the circuit.

 

After these leakage issues are handled, then we have the matter of regulation.  As long as your regulator is good, low-Z, and can supply the current that you need with low noise (circuit noise, picked up coupled and radiated noise -- most people don't know that radiated/coupled are different), then you are pretty much home free assuming a sane layout and no wierd hidden currents causing problems.   Circuit noise in a regulator circuit can make a difference.  But, if a commercial circuit (even preamp circuit) is very sensitive to regulator circuit noise, then the preamp itself needs better consideration for the power input.   A hobby built circuit is a different story -- who knows how much robustness has been designed-in to a hobby purpose design?

 

The other thing is the resistance/impedance/shielding of whatever connecting wire that you use.   When in doubt, use an RF choke at junctions from the outside world into a box.  Whatever impedance problems there will be will likely be soaked up by some hopefully already built-in capacitance between the power leads inside the design getting the power.

 

Yes, a lousy power supply can cause audible defects.   The transition from a good industrial quality, for purpose supply to an incredibly good 'elite' power supply needs GOOD CONTROLS for verifying  the improvements, because they will be very, very small.  More than likely, significantly improved results come from another variable that has leaked in -- like missing transformer shielding & missing RF choke.

 

If there are improvements by fancy changes beyond a well designed industrial quality supply (the only kind I have ever designed, and they lasted for DECADES, with no noise problems with the sensitive thermocouple & thermistor inputs being powered) -- then, I'd look for the acutal reason for improvement be a shielding/coupled even conducted/ground noise problem -- that some 'fancy' design change might finess around other issues.

 

You are very unlikely to be very sensitive to significant 'power supply' design changes if you do use a shielded transformer and follow good grounding apply RF chokes wisely.  Also, the various components being powered should already be somewhat robust WRT power/grounding/conducted/coupled/radiated noise sources.

 

All this said, not all equipment is prudently designed -- but if a design is so fragile that moving from a well designed power supply to an elite power supply makes a differnece, then the improvement is likely coming from somewhere else unexpected.

 

John

 

[bernardl]

Isn't that a case that when you looking for small improvements you end up considering them large if you think you notice them?

 

To me it's a statistical game where adding up possible small improvements on top of each others in a system may end up resulting in a better sounding system as a whole.

 

Well designed LPS are generally speaking to contribute in various ways, so are better power cable, power filtering,... I think that moving from a stock Mac Mini to one driven by a Mojo Audio Illuminati V2 (probably one of the very best LPS on on the market) did improve the sound in my system. I am pretty sure it did. Would changing the stock PS of my Melco s100 audiophile hub to to a high end LPS have a significant impact? I frankly doubt it... but I'll probably do it at some point... to be sure... 🙂

 

We should always be aware of the dangers of confirmation bias. It's all too easy to get our hopes turn uncertain changes into improvements when we believe we are on the right track.

 

Cheers,

Bernard

 

[sandyk]

2 hours ago, SJK said:

 

What say you to that?  You can be abusive if you like, or you can stay on topic.  I'm fine with it either way.

 

Better still, I will completely ignore you, as you are simply not interested in anything that myself, AlexC (and in turn highly experienced E.E. John Swenson have to say on this matter)

 

 As this has been made into a technical discussion requiring Objective answers (Proof), it should be taken to the Objective area of the forum.

[sandyk]

9 hours ago, davide256 said:

I can't offer you explanations, only the observation that in my gear improving DC power supply has been crucial for improved resolution of lower db level signals

and elimination of USB digital irritants. And that the cost /benefit equation (~$500 per power upgraded component) has been far cheaper

than any next equipment upgrade

 

And the approximate level at which these improvements have been noted as the PSU area is further improved , are quite measurable as to the noise level and output impedance of the PSUs used.

IOW, In this case, Objective measurements are able to confirm Subjective reports.

[sandyk]

14 hours ago, Summit said:

 

This is not correct IMO. SMPS's advantage are its small size, low weight, high efficiency, low heat radiation and most important low cost per watt.

 

It’s not that simple that a linear power supply is always quiet electrically. Many LPS are sensitive to DC offset and both hum and radiate a lot of EMI.

 

Am not saying that SMPS is better sonically, but a quality SMPS is normally better than a low quality LPS for the same watts and price.

 

To answer the OP question, can a linear supply actually make any difference? Yes it can, but that it is linear is no guaranty. If it was, no respectable hifi manufacturer would use SMPS.

 

Hi Summit

 Gary is very well qualified in this area. His reply was about the typical use of generic SMPS as a cost cutting measure in many cheaper components, and also used to reduce the size of the equipment which also translates to a further cost advantage.

 The key word in your reply is a quality SMPS, with a few manufacturers having their SMPS made to improved specifications.

 

Alex

[davide256]

5 hours ago, SJK said:

OK, now we're on the right track.  Someone who has made a change in an external power supply and believes that it has made a difference in the sound of the the system.  

 

I find it interesting on how people have a hard time staying on topic with this, and insist on wandering off mumbling about how this and that obviously has to make a difference.  

 

Davide, perhaps you could give us a bit more information on how the change in power supply made a difference to your system.  It doesn't have to be technical, we seem to have technical depth on the design side well covered.  

 

Remember, this is and Audiophile forum, not an Electrical Engineering forum.

Part of the battle with digital I find to be eliminating irritants and artifacts (a.k.a. from Galaxy Quest "thats not right"). I've been through a  stock SMPS, SoTM SPS500, HDplex200W and my last purchase an Uptone Audio JS-2. The sense of ease for my sound has gotten much closer to my vinyl playback solution. As I improved

power supply for NUC USB source, my ISO Regen became superfluous, hindered more than helped. I do think power supply affects sound quality, but its along

the lines of "how pure are the colors in your paintbox".. a poorer power supply means somethings added to the sound that doesn't belong,

that distracts from the music.

 

[StephenJK]

2 hours ago, sandyk said:

Hi Summit

 Gary is very well qualified in this area. His reply was about the typical use of generic SMPS as a cost cutting measure in many cheaper components, and also used to reduce the size of the equipment which also translates to a further cost advantage.

 The key word in your reply is a quality SMPS, with a few manufacturers having their SMPS made to improved specifications.

 

Alex

Who knew?

 

I thought this was an audiophile forum where we could discuss various topics without someone having a different opinion becoming deeply offended.  

 

My post was the result of two things. 

 

The first was a person who had posted as to whether changing out their LPS for his NUC could possibly make a difference in the sound.  And there's me, going "what the hell is a NUC?"

 

And then, as I Google it, it turns out that CC from this very site has written a detailed "how to" on that very topic!

 

Courtesy of our friends at Amazon, I now have a NUC with RAM installed and just waiting for the SSD to show up on Monday to load a Roon ROCK.  And then I can get it all setup to replace the hardware I'm using now. 

 

But then, being a designer of power and control systems for industrial machines - not stereo gear, I thought there might be a topic for discussion, and the premise was simple.

 

Could that external power supply for that NUC possibly make any difference in the sound of a stereo system?

 

I apologize for bothering all of you and promise that it will never happen again.

 

Cheers,

 

Stephen

 

 

 

 

[sandyk]

 

John Dyson who is qualified in this area also posted some good information in #27

Quote

Don't explain to me how I'm wrong, prove it.  Prove it with recordings of how this version sounds better than that version with this power supply or that power supply

 

 BTW, this was the reason I responded the way I did.

That was an unreasonable demand to make of the majority of members. 

[One and a half]

18 hours ago, Summit said:

 

This is not correct IMO. SMPS's advantage are its small size, low weight, high efficiency, low heat radiation and most important low cost per watt.

 

It’s not that simple that a linear power supply is always quiet electrically. Many LPS are sensitive to DC offset and both hum and radiate a lot of EMI.

 

Am not saying that SMPS is better sonically, but a quality SMPS is normally better than a low quality LPS for the same watts and price.

 

To answer the OP question, can a linear supply actually make any difference? Yes it can, but that it is linear is no guaranty. If it was, no respectable hifi manufacturer would use SMPS.

 

 

Transformers are sensitive to DC offset, not the bits after the transformer secondary. A transformer manufacturer doesn't expect the power source to contain enough notches to cause hum, a transformer expects a clean zero transition, it's up the consumer to provide a clean notch free voltage or IOW 'connect the transformer to a suitable power supply".

 

SMPS can comply to EMC rules within themselves, but connect them to a load and that certification is shot, that's clear in the added pdf.

 

Magnetic interference can be controlled with design techniques for the transformer, ask any tube amplifier designer.

 

Respectable hi fi manufacturers (some) that I could think of...

Here's a list of amplifier manufacturers that use linear approaches to the main drive and in their pre-amplifiers:

 

Adcom

Accuphase

Ayr Acoustics

Bricasti

Macintosh

Luxman

Soolution

Pass

and countless more thousands

 

Here's a list of some amplifier manufacturers that use SMPS approaches to the main drive:

 

Benchmark

Hypex

90% of modern AV amps

 

[One and a half]

2 hours ago, SJK said:

But then, being a designer of power and control systems for industrial machines - not stereo gear, I thought there might be a topic for discussion, and the premise was simple.

You should be aware then of the implication of noise on serial communications, shielding and grounding techniques for cables, and noise coupling from one voltage system to the other. Audio is really no different, if you start with a poor power supply full of noise, then that noise is propagated through the machine's system where it can affect the operation of sensing equipment.

 

 

[Summit]

Paul McGowan have explained what power supplies actually are, how they work, why they are different and how Switch Mode Power Supplies can be made to sound good. Yes it’s a long series but is packed with information and IMO easy to read and understand. Best to read them in the right order.

 

https://www.psaudio.com/pauls-posts/smps/

https://www.psaudio.com/pauls-posts/transformers-2/

https://www.psaudio.com/pauls-posts/smaller/

https://www.psaudio.com/pauls-posts/choppers/

https://www.psaudio.com/pauls-posts/bucking-trends/

https://www.psaudio.com/pauls-posts/i-wonder/

https://www.psaudio.com/pauls-posts/plus-and-minus/

https://www.psaudio.com/pauls-posts/regulations/

https://www.psaudio.com/pauls-posts/size-freight-cars/

https://www.psaudio.com/pauls-posts/sounds-good-true/

 

[Summit]

9 hours ago, sandyk said:

Hi Summit

 Gary is very well qualified in this area. His reply was about the typical use of generic SMPS as a cost cutting measure in many cheaper components, and also used to reduce the size of the equipment which also translates to a further cost advantage.

 The key word in your reply is a quality SMPS, with a few manufacturers having their SMPS made to improved specifications.

 

Alex

 

Alex I have no interest in debating who is qualified. I share what I believe to be correct and will point out pros and cons of different technology, no matter what. I did not and have never liked cheap wall warts, but it’s a big difference between those cheap wall wart and a quality SMPS that is used in Linn’s or Chords DACs for example. That was my subject. I was pointing out that am not saying that SMPS is better sonically, only that a quality SMPS is normally better than a low quality LPS for the same watts and price.

[sandyk]

50 minutes ago, Summit said:

 

Alex I have no interest in debating who is qualified. I share what I believe to be correct and will point out pros and cons of different technology, no matter what. I did not and have never liked cheap wall warts, but it’s a big difference between those cheap wall wart and a quality SMPS that is used in Linn’s or Chords DACs for example. That was my subject. I was pointing out that am not saying that SMPS is better sonically, only that a quality SMPS is normally better than a low quality LPS for the same watts and price.

 

  I agree that a quality SMPS is capable of outperforming a cheap Linear PSU, especially one  like that basic supply suggested by the OP, even if followed by a LM317 voltage regulator.

[manueljenkin]

The place to start with would be to understand how a transistor behaves with power supply fluctuations.

 

Start with the most abstract model around. Ideal power supply. Then look into one level deeper but still a abstraction - power supply rejection ratio. Then start looking into non linear power profiles of transistor operation, their internal capacitance resistance parameters etc and quantum effects.

 

In short, yes power supply quality will affect sound.

[manueljenkin]

Speaking of good quality SMPS, I think burson fun should be given a chance. Really inexpensive and sounds great.

[John Dyson]

8 hours ago, manueljenkin said:

The place to start with would be to understand how a transistor behaves with power supply fluctuations.

 

Start with the most abstract model around. Ideal power supply. Then look into one level deeper but still a abstraction - power supply rejection ratio. Then start looking into non linear power profiles of transistor operation, their internal capacitance resistance parameters etc and quantum effects.

 

In short, yes power supply quality will affect sound.

It is more about how a circuit all together, including power supply functions.   Few circuts contain a transistor by itself.  In fact, when we start talking about 24bits of resolution, everything in a circuit needs to be considered, including the circuit board being a part of the circuit.  After you do a bit of upper RF/lower microwave design, which still has similar aspects to 'normal' circuitry, you start thinking of a circuit in a more holistic standpoint.   That trace is part of the circuit just as a big fat inductor (depending on where in the circuit.)  Even the layout or even 3d space in the circuitry itself is part of the circuit.

 

One problem that apparently happens is that the traditional concept of a audio frequency schematic representing a circuit that is in an environment with non-audio frequency aspects.  Often, an 'audio only' design will result in vulnerabilities.    To be safe, you use an RF (probably UHF/lower microwave) sensibility when looking at the circuit as a whole.  Of course, the proportions are different than an actual microwave design -- but the fact that layout might have to e carefully considered.   This 'layout' thing also extends to power supply characteristics,  (Please, if you REALLY want reliable low noise -- use a shielded transformer.)

 

Similar in concept is when you design an RF amplifier, a more optimal, linear design will be created if the audio frequency & lower characteristcs are considered (e.g. intermodulation distortion.)   There are concepts where audio-range feedback is used in an RF-only amplifier to mitigate certain kinds of distortion.

 

I haven't done an EE design in decades, but one thing that I found -- often, it is more complex than the superficial picture on a schmatic.  Don't think in terms of 'parasitics' in the deisgn, but instead the components that used to be called 'parasitics' are a natural part of the design -- sometimes actually considered as part of the schematic.   Of course, great experience EVENTUALLY support shortcuts, but too often it seems like the experience/developing expertise step in career evolution is skipped -- then we end up with fragile combinations of componentry..

 

John

 

[manueljenkin]

7 minutes ago, John Dyson said:

It is more about how a circuit all together, including power supply functions.   Few circuts contain a transistor by itself.  In fact, when we start talking about 24bits of resolution, everything in a circuit needs to be considered, including the circuit board being a part of the circuit.  After you do a bit of upper RF/lower microwave design, which still has similar aspects to 'normal' circuitry, you start thinking of a circuit in a more holistic standpoint.   That trace is part of the circuit just as a big fat inductor (depending on where in the circuit.)  Even the layout or even 3d space in the circuitry itself is part of the circuit.

 

One problem that apparently happens is that the traditional concept of a audio frequency schematic representing a circuit that is in an environment with non-audio frequency aspects.  Often, an 'audio only' design will result in vulnerabilities.    To be safe, you use an RF (probably UHF/lower microwave) sensibility when looking at the circuit as a whole.  Of course, the proportions are different than an actual microwave design -- but the fact that layout might have to e carefully considered.   This 'layout' thing also extends to power supply characteristics,  (Please, if you REALLY want reliable low noise -- use a shielded transformer.)

 

Similar in concept is when you design an RF amplifier, a more optimal, linear design will be created if the audio frequency & lower characteristcs are considered (e.g. intermodulation distortion.)   There are concepts where audio-range feedback is used in an RF-only amplifier to mitigate certain kinds of distortion.

 

I haven't done an EE design in decades, but one thing that I found -- often, it is more complex than the superficial picture on a schmatic.  Don't think in terms of 'parasitics' in the deisgn, but instead the components that used to be called 'parasitics' are a natural part of the design -- sometimes actually considered as part of the schematic.   Of course, great experience EVENTUALLY support shortcuts, but too often it seems like the experience/developing expertise step in career evolution is skipped -- then we end up with fragile combinations of componentry..

 

John

 

Agreed 100%. Transistors are very pedantic devices in terms of behaving wild to random aberrations. A high frequency noise can still harm the normal functioning of transistor even if our input sigal is in audio band.

 

Benchmark had an article on RF noise consideration when designing their amps.

[StephenJK]

On 6/20/2020 at 11:34 PM, One and a half said:

You should be aware then of the implication of noise on serial communications, shielding and grounding techniques for cables, and noise coupling from one voltage system to the other. Audio is really no different, if you start with a poor power supply full of noise, then that noise is propagated through the machine's system where it can affect the operation of sensing equipment.

 

 

Sorry, but the SJK account had to be closed due to MS issues, but my original it would seem is still active, and if you don't mind I'll use that to reply.  

 

The experience that I have with designing and building power and control systems for industrial machines isn't something that I feel I need to explain or defend to anyone, particularly not an anonymous internet group.  

 

The premise was simple and basic - whether a high cost or low cost linear power supply could possible affect the sound.

 

Now, you're all debating the merits of a nasty switch mode harmonic nightmare that was developed to be smaller, cheaper and to use less power.  

 

Let's get back on track.  If you want to start your own post on how magical SMPSs then please do so. 

 

But don't hijack my post, and then go on and on without addressing the original question. 

 

Which nobody has done, except for Alex, who has explained "That was an unreasonable demand to make of the majority of members."

 

As I've stated before, you can post up articles until the cows come home.  Stereo gear is about the sound, not about the schematics.

 

 

[sandyk]

47 minutes ago, StephenJK said:

Which nobody has done, except for Alex, who has explained "That was an unreasonable demand to make of the majority of members."

 

As I've stated before, you can post up articles until the cows come home.  Stereo gear is about the sound, not about the schematics.

 

As I also stated, I did just that recently (Thursday June 15) for another member who I know has equipment suitable of demonstrating these differences, in this case ALSO a decent external monitor instead of a cheap laptop, where he was then able to report both SEEING and HEARING differences at the same time. It's pretty hard to dismiss what both your eyes and ears are telling you at the same time.

As both Digital A and V use 1s and 0s they are both subject to PSU shortcomings.

[StephenJK]

2 hours ago, sandyk said:

As I also stated, I did just that recently (Thursday June 15) for another member who I know has equipment suitable of demonstrating these differences, in this case ALSO a decent external monitor instead of a cheap laptop, where he was then able to report both SEEING and HEARING differences at the same time. It's pretty hard to dismiss what both your eyes and ears are telling you at the same time.

As both Digital A and V use 1s and 0s they are both subject to PSU shortcomings.

Dude,

 

You really need to stop with the capital letters and bold text - it adds no value.

 

On the the bright side, you will be pleased to know that courtesy of an excellent "how to" from CC of this site, I now have my NUC up and running.  I was waiting for the SSD that showed up this morning and can now use the M6500 for more suitable tasks. 

 

I've posted a picture for you of my stereo system where "any change in power supplies likely wouldn't be noticeable".  

 

Cheers,

 

Stephen

[John Dyson]

Well, the statement that a 'power supply can affect sound quality' is a true statement.  It is a sad state of affairs on a system where it is true -- not because of the system owner.   The reason why it is a sad state of affairs is a matter of design competency.   Nothing in audio (except for certain digital pieces) is high tech at all, analog EE is pretty much the same as it was 40yrs ago.  The mixed audio/RF design techniques required by some digital circuitry are also VERY WELL understood. Sure, there are newer components, better semiconductor processes (lower 1/f noise), but those aren't showing the advantages IF power supply quality becomes a factor.  Of course, there is the matter of ill considered design as a whole (considering the entire circuit environment as being part of the design.)

 

If a properly specified power supply doesn't fill the bill -- then someone did something wrong.  IT is NOT the fault of the consumer that they were lied to.   I guess a misapplication could happen, but this is all a matter of ENGINEERING and STANDARDS.   Weak standards, poor engineering, each can make a system be fragile.

 

An audio consumer should not have to try to be an engineer -- because apparently a lot of so-called developers are not even good 'engineers'.  How can a hobbyist with a real job spend as much time in learning/keeping up as a full time paid engineer?   Someone is being sloppy, too much cost reduction, too much spending on 'industrial design' (consumer packaging) instead of on the integrity of the whole product design.

 

I think the reason why people who used to be engineers like me might mistakenly say 'no', a power supply cannot make a difference.  It is because the fact is: there is no good reason why a power supply should cause any problems, make even slight differences. (I am specifically discounting absurd small  parameter differences as being a 'difference'.)

 

John

 

[sandyk]

10 minutes ago, StephenJK said:

Dude,

 

You really need to stop with the capital letters and bold text - it adds no value.

 Dude

 Neither does posting  a photo like you have done, with no explanation as to what the actual components are, so  that others are able to

make their own minds up as to whether or not this is a great system.

[StephenJK]

18 minutes ago, sandyk said:

 Dude

 Neither does posting  a photo like you have done, with no explanation as to what the actual components are, so  that others are able to

make their own minds up as to whether or not this is a great system.

The one thing that would be difficult to identify would be Jax - one of our Maine Coon cats.  Poor little guy just got diabetes and is having a hard time getting around, but he does love his tunes.

 

Top:  Clearaudio Innovation Compact with the Universal tonearm, VTA lifter and a Dynavector Te Kaitora Rua cartridge.

 

Middle:  A pair of Devialet Expert Pro 440 monoblock digital amplifiers, 440 W per side.

 

Bottom:  Some kind of power gizmo, supposed to filter etc. with a network switch, NUC and LaCie USB drive.

 

Speakers:  KEF Blades.

 

Any more questions?

 

Edit:  The art print is the Philip Garris cover art for the Grateful Dead's "Blues for Allah" album.  

[sandyk]

3 minutes ago, John Dyson said:

I think the reason why people who used to be engineers like me might mistakenly say 'no', a power supply cannot make a difference.  It is because the fact is: there is no good reason why a power supply should cause any problems, make even slight differences. (I am specifically discounting absurd small  parameter differences as being a 'difference'.)

 John

It is easily demonstrated by both measurements and using a C.R.O. that a simple  PSU like the OP posted, even with a LM317 voltage regulator following it, is incapable of rejecting HF rubbish such as the harmonics from an SMPS and is grossly inadequate for the best performance from a Digital front end, or even an Analogue Preamplifier , and more so the RIAA Phono Preamp for the TT in the photo ,

even though it MAY be satisfactory for the output stage of an amplifier.

 

Regards

Alex