Let's stop calling Class D amplifiers "efficient" when they are not.

[mhardy6647]

You'll be cutting down lots more trees for those speakers. Sure you've thought this thru?

I prefer to think of it as carbon sequestration.

 

[fpitas]

Although I don't care about the idle power per se, if parts of the amps really do overheat in normal use that is a valid discussion point for ASR.

 

[Chr1]

---

Reckon idle consumption, though possibly less important, is still relevant here. After all it is one of the primary negatives of Class A. I also bet loads of peeps didn't realise that Class Ds idle use can be as high as it sometimes is. I certainly didn't.

 

[mhardy6647]

The "hard power off" switch was and still is one of the greatest resource-conserving devices known to Man people beings.

 

[fpitas]

The "hard power off" switch was and still is one of the greatest resource-conserving devices known to Man people beings.

Exactly. I just turn the system OFF when not in use.

 

[Chr1]

Even when you get lunch?
Or go to the john/loo?
Petty, I know. But still relevant

(PS I occasionally use a valve amp with 140w idle. Mainly in the winter!)

 

[fpitas]

Well, if you care a lot about idle power, I certainly won't stop you. It's just not high on my list.

 

[pma]

Beating a dead horse, as usual at ASR.

 

[Chr1]

Beating a dead horse, as usual at ASR.

All good... Why so cheery?

I will probably be crucified for using the car analogy again, but there's horses for courses surely...
Only using a fraction of an amps power, if it has a high idle drain is like having a race car but only using it round town instead of a track. Nothing wrong with it per se, but it definitely wastes fuel. Regardless of class A, AB, D whatever.
(Good excuse for us blokes to have several vehicles/hifi rigs too surely. Does anyone here really only have one amp?)

 

[ahofer]

Does anyone here really only have one amp?

One in each of two homes now, does that count? But only recently thanks to selling two three.

 

[Chr1]

I definitely have way more amps than I need then, given I only have one home. Anyway, this thread indicates that in order to save the planet and not waste money, I'd best keep at least a few...Ahem.

 

[JeremyFife]

20 pages in and I've learned that Amps use electricity when they idle, and that I should never buy a new Amp (but should find one from the 70's and learn how to fix it).

Actually it's an entertaining and sometimes informative thread.

What does worry me is the implicit (pretty explicit from some) finding that most/some/all Hypex implementations have poor thermal management and will fail early... and that I need to spend up for a Purify (or something from the 70's)
Is this view backed up by anyone, apart from John? This I do find concerning.

 

[ahofer]

What does worry me is the implicit (pretty explicit from some) finding that most/some/all Hypex implementations have poor thermal management and will fail early... and that I need to spend up for a Purify (or something from the 70's)
Is this view backed up by anyone, apart from John? This I do find concerning.

I have a 252 amp from March Audio that does not seem to run particularly hot (and I turn it OFF when not in use). ou can find some discussion of heat in his various nCore units here:

March Audio Hypex Ncore Power Amplifiers

See the main Hypex website (not the DIY website); they only list them for OEMs at present. https://www.hypex.nl/ Hypex have a clear OEM policy. The 500 won't become available for DIY.

www.audiosciencereview.com

 

[Chr1]

Presumably thermal cycling affects Class D too, so as with other amps the question is: at what point do you err on the side of saving energy vs stress on the relevant components? A personal judgment call really, I guess. Cost to the climate and wallet vs longevity. And possibly different depending on the particular amp?

 

[Blumlein 88]

20 pages in and I've learned that Amps use electricity when they idle, and that I should never buy a new Amp (but should find one from the 70's and learn how to fix it).

Actually it's an entertaining and sometimes informative thread.

What does worry me is the implicit (pretty explicit from some) finding that most/some/all Hypex implementations have poor thermal management and will fail early... and that I need to spend up for a Purify (or something from the 70's)
Is this view backed up by anyone, apart from John? This I do find concerning.

IcePower units seemed to have stood the test of time somewhat. I don't know who if anyone is using those anymore. I do know of several personally that are 12-15 years old and are running along just fine.

Same for better Tripath units. Tripath is now mostly in really cheap low to moderate power units that are as cramped up as possible. I wouldn't expect great longevity.

As always really good data on this sort of thing is hard to come by. Even the vintage stuff was not all good nor anywhere close to forever amps. Devil is always in the details. In my opinion the easiest amps to keep going forever are vacuum tube units. As long as someone makes the tubes. You already have some SS designs where this or that transistor isn't available. You can probably do a work around for most, but not for all. Hitcahi Power MOSFETs come to mind. Popular for a minute, but I don't think you can get anything that is a drop in replacement if you need it.

The efficiency that really matters is economic. Have a great performing amp that lasts 5 years for $200, another that lasts 10 years for $500, another that might last the average lifetime for $2500. Which is the best deal? And do you know what amp you want to own or need for the next 40 years? Yeah....right.

It would be my opinion the Purifi is the best of current designs. Were I buying an amp that is what I would get.

 

[fpitas]

do you know what amp you want to own or need for the next 40 years?

Since they all have a unique sound, I'll have to try them all!

/

 

[Chr1]

My AVR, a Pioneer SC-LX86 uses ICE modules and seems to run cool and is almost 10 years old now. It never seems to use much more than 85W (it's idle draw) no matter how loud I go. It only powers C, SL, SR, SBL and SBR channels tho as I use two external power amps for the others. From what I can gather it is actually the DSP chip using most of the power at idle.

I will confess to having two class A power amplifiers. One valve, one valve/Hitachi Mosfet hybrid. The VTL valve draws 140w idle, the Lazarus hybrid 175w. I definitely try to avoid thermal cycling them. Particularly the Lazarus as from what I can make out the Mosfets are hard to replace now. Moderate use only then.

 

[Blumlein 88]

Since they all have a unique sound, I'll have to try them all!

/

Well the ICEpower units were sensitive to the load of the speaker with audibly varying response in the upper end. The others either have it reduced to a low enough level or in the case of Purifi it appears not to be an issue. Tripath units were worse about this than ICEpower.

 

[fpitas]

Well the ICEpower units were sensitive to the load of the speaker with audibly varying response in the upper end. The others either have it reduced to a low enough level or in the case of Purifi it appears not to be an issue. Tripath units were worse about this than ICEpower.

A friend has old Hypex UcD180s. As I recall from PMAs testing here, they're not bad at all.

 

[Audio Science Pal]

Reading comments in this thread gives me the impression that the 120V amps/power supplies seem to idle and standby at lower temperatures than the 220V versions.

That is not my experience. I can feed the switchable (auto or manual) power supplies from multitapped step up/down transformers. There is a minor variation (~10%) between the upper and lower allowable range for the two nominal voltages.

Then maybe it is the 60Hz vs 50 Hz difference leading Australians to experience more warmth, while Americans report that their amps are cooler?