Switching Power Supplies in AV Receivers

[PENG]

Could care less about the specs, How the amp sounds? Flat? sterile sounding? Many Tube amps..will sound a 100,000.00 times better and they don't have switching power supplies with a much better >damping factor (○○)

haha, I maybe the opposite, all well design and build amps sound great to me as long as the recording/mastering of the source media is good, so for amps, I care mainly about the specs and bench test data. I believe most (not all) reports of hearing night and day difference between well design amps are Placebo effects or other factors, (example: not apple to apple comparison).

 

[highfigh]

Just like anything else, there are advantages and disadvantages to SMPS.

For me, in general think that the disadvantages outweigh the advantages from a performance and reliability aspect. Over the years, I have had many SMPS fail on me in computers and for lab instrumentation at work. On the other hand, I can't recall a single linear PS failure in my experience.

Of course, it depends on the application.
If I need/want cheap, lightweight, less heat, or portability, then SMPS becomes a no-brainer. If I have a permanent install, then linear likely makes more sense unless heat management is a concern.

So, for 2 channel music in my home, I will personally choose a linear supply and Class A or A/B every time. For home theater where I may have a stack of gear, possibly enclosed, and I may not be quite as critical on the listening, then SMPS and Class D makes a lot more sense.

So, that's the real question to answer: What's the goal? What's the best tool to accomplish the goal?

What works best? Define the goals and pick something. Without defining everything, it's more likely that the choice will be wrong.

 

[Verdinut]

I hope you are right, because linear PS really has to go eventually for their disadvantages in terms of weight and efficiency. I would probably still prefer class A if I can manage the heat (I don't even like hot summer days) 20 years from now, but I hope 99.999% of the population will go with something of much better efficiency that still produce hifi sound quality. Everything being equal, I still want near 0 distortions of any kind, knowing full well that I am unable to discern the difference in sound quality regardless but I also know that is just being silly.

PENG,

IMO, I doubt that someone can hear a difference between a near 0 distortion Class A design and a near 0 distortion Class AB one. The fact that the output stage of a Class AB amp is appropriately biased should make it sound like the Class A type if it's properly designed and has equivalent distortion and other spec figures.

What say you?

 

[Verdinut]

Oh, I agree that QSC has some incredible engineers and some great products on the market. They were pretty heavily featured in an issue of the AudioXpress Voice Coil Magazine a few years ago.

Looks like you have your goal and you know how you want to achieve your goal. But, that doesn't mean that your approach will be my approach to reach my goal.

I am a big proponent of simple, elegant solutions. SMPS designs are neither simple nor elegant, I'm pretty sure we can agree there, right?

Slipperybidness,

Your reference to the AudioXpress Voice Coil Magazine really interests me. Would you happen to have a copy of the issue or do you think there might be a possibility of getting the article from the magazine for instance?

 

[slipperybidness]

Slipperybidness,

Your reference to the AudioXpress Voice Coil Magazine really interests me. Would you happen to have a copy of the issue or do you think there might be a possibility of getting the article from the magazine for instance?

I realized that it was definitely in the AudioXpress mag family, but there is a chance that I was mistaken about the "VoiceCoil" aspect (I know that when I get newsletters via email it always says AudioXpress VoiceCoil, I haven't suscribed in a couple years and I think I sold all my back issues to Half Price Books).

It's been quite a while, but I'm about 90% sure that this is the article that really brought QSC to my attention, and really got my confidence in their equipment and engineers. Really, this is the stuff that you want to see from an engineering and R&D team!

If this article doesn't make you a QSC convert, then nothing will
http://www.audioxpress.com/files/attachment/2596

Anyway, a simple search also finds other articles:
http://www.audioxpress.com/tags/QSC

And, if you are not familiar with AudioXpress---I HIGHLY recommend that mag! I think one of the main reasons I let my scrip run out is b/c I couldn't get the student discount on a renewal.

Side Note: We have a bar/nightclub downtown here that always advertises "Audio by QSC". Which always seems a little odd to me b/c the general public likely has no idea what that means, and I haven't really seen that advertised like that for other venues either.

 

[Verdinut]

I realized that it was definitely in the AudioXpress mag family, but there is a chance that I was mistaken about the "VoiceCoil" aspect (I know that when I get newsletters via email it always says AudioXpress VoiceCoil, I haven't suscribed in a couple years and I think I sold all my back issues to Half Price Books).

It's been quite a while, but I'm about 90% sure that this is the article that really brought QSC to my attention, and really got my confidence in their equipment and engineers. Really, this is the stuff that you want to see from an engineering and R&D team!

If this article doesn't make you a QSC convert, then nothing will
http://www.audioxpress.com/files/attachment/2596

Anyway, a simple search also finds other articles:
http://www.audioxpress.com/tags/QSC

And, if you are not familiar with AudioXpress---I HIGHLY recommend that mag! I think one of the main reasons I let my scrip run out is b/c I couldn't get the student discount on a renewal.

Side Note: We have a bar/nightclub downtown here that always advertises "Audio by QSC". Which always seems a little odd to me b/c the general public likely has no idea what that means, and I haven't really seen that advertised like that for other venues either.

Slipperybidness,

I was actually familiar with the AudioXpress cause I bought several of the mags in the past. A very serious magazine indeed.
Thanks so much for the information.
Cheers,
André

 

[PENG]

PENG,

IMO, I doubt that someone can hear a difference between a near 0 distortion Class A design and a near 0 distortion Class AB one. The fact that the output stage of a Class AB amp is appropriately biased should make it sound like the Class A type if it's properly designed and has equivalent distortion and other spec figures.

What say you?

I am saying the same thing, but I prefer class A regardless. Just like I know my AVR-3805 sounds as good as the Halo A21/Cambridge Audio class A preamp sitting right next to it, but I prefer the Halo amp.

 

[PENG]

Verdinut, please don't misunderstand me, I am really in agreement with you that everything being equal class AB is better and hopefully preferred by near 100% of the potentially buyers if just for the lighter weight and effciency. I don't even own a class A power amp, except my Halo and Bryston both operates in class A at low output level (8 for the Halo, 20 to 25 for the Bryston). No I can't hear the difference due to IMD contents between my amps and AVRs, but I feel good knowing that it is not there or at near 0 level. In class AB amps, IMD (caused by the inherent crossover distortions), could theoretically be all but eliminated, if their bias controls are done well.

Also note that not all class AB amps are designed the same, so some, hopefully only some entry level ones, may have IMD that are high enough for critical ears to detect.

 

[Bucknekked]

Verdinut, please don't misunderstand me, I am really in agreement with you that everything being equal class AB is better and hopefully preferred by near 100% of the potentially buyers if just for the lighter weight and effciency. I don't even own a class A power amp, except my Halo and Bryston both operates in class A at low output level (8 for the Halo, 20 to 25 for the Bryston). No I can't hear the difference due to IMD contents between my amps and AVRs, but I feel good knowing that it is not there or at near 0 level. In class AB amps, IMD (caused by the inherent crossover distortions), could theoretically be all but eliminated, if their bias controls are done well.

Also note that not all class AB amps are designed the same, so some, hopefully only some entry level ones, may have IMD that are high enough for critical ears to detect.

Peng
How many times have you had this same Class A, Class AB, Class what-the-freak discussion/minor disagreement ? I just took at look at this thread and it seemed like major echoes and deja vu from the last 1/2 dozen times I saw the same discussion, with the same end points.

In my mind, you have this topic figured out, sliced and diced, edited and noted, summarized and annotated and generally mastered (if mastery is a thing in audio). It would seem that all you should need to do from here on out is just cut n paste from previously cited writings, put in hotlinks, or just use footnotes.

You could also just go with ibid. Save yourself some aggravation and typing.

If I ever have another amplifier question, I know right where to go. If there's something you don't know about amps, I'm not sure its relevant or audible. Its not likely that I will have one anytime soon because I took your advice on my last purchase and it sounds fantastic and probably will keep sounding fantastic for years. Be well.

 

[PENG]

Peng
How many times have you had this same Class A, Class AB, Class what-the-freak discussion/minor disagreement ? I just took at look at this thread and it seemed like major echoes and deja vu from the last 1/2 dozen times I saw the same discussion, with the same end points.

In my mind, you have this topic figured out, sliced and diced, edited and noted, summarized and annotated and generally mastered (if mastery is a thing in audio). It would seem that all you should need to do from here on out is just cut n paste from previously cited writings, put in hotlinks, or just use footnotes.

You could also just go with ibid. Save yourself some aggravation and typing.

If I ever have another amplifier question, I know right where to go. If there's something you don't know about amps, I'm not sure its relevant or audible. Its not likely that I will have one anytime soon because I took your advice on my last purchase and it sounds fantastic and probably will keep sounding fantastic for years. Be well.

The information are scattered all over the forum, maybe time for AH to setup an effective FAQ section that deals with repeat questions/responses/debates.