Class D power amplifiers

Are class D amps finally ready for prime time for audioholics, even audiophiles, if not why not?

  • Yes

    Votes: 38 67.9%
  • Yes, but probably not audiophiles

    Votes: 2 3.6%
  • May be, it depends..

    Votes: 7 12.5%
  • Don't know

    Votes: 5 8.9%
  • No, they are not ready for prime time because..

    Votes: 1 1.8%
  • Yes, but only those with good specs confirmed by bench tests

    Votes: 6 10.7%

  • Total voters
    56
3db

3db

Audioholic Slumlord
All my systems are AVR based so unfortunately for me, the move to one of these new class D amps would be an expensive outlay as I would need to replace the AVR with a mininimum of 5 amps (unless they come in multichannel configurations) plus an AVR processor. Although these amps output power makes even my RX-A3060 look like a toy, power for me was never issue as my rooms are not all that large and the PSBs are easy to drive. If this was available when I first got into the hobby, then I would have definately gone for this route.

I also echo ACCUdefTechguy's sentiment that AVR manufactures should move to classD and slim these "fatboys" down a lot. Cooling would be no longer an issue and as a result reduces the footprint of the audio rack.
 
AcuDefTechGuy

AcuDefTechGuy

Audioholic Jedi
All my systems are AVR based so unfortunately for me, the move to one of these new class D amps would be an expensive outlay as I would need to replace the AVR with a mininimum of 5 amps (unless they come in multichannel configurations) plus an AVR processor. Although these amps output power makes even my RX-A3060 look like a toy, power for me was never issue as my rooms are not all that large and the PSBs are easy to drive. If this was available when I first got into the hobby, then I would have definately gone for this route.

I also echo ACCUdefTechguy's sentiment that AVR manufactures should move to classD and slim these "fatboys" down a lot. Cooling would be no longer an issue and as a result reduces the footprint of the audio rack.
I have a 26ft x 22ft x 14ft ceiling HT room with 9 speakers and 10 subs (5.2.4). All nine speakers are powered by the Yamaha MX-A5000, which is basically what's in the Yamaha RX-A3000-series AVRs. The 10 subs are all powered by the ATI amps.

In my 23x24x12 wide-open-floor-plan living room, I have the RBH SVT towers (2.2CH). The RX-A3080 powers the 2 x SV831R (4 ohms). And the SV-1212N subs are powered by a sub amp.

So most of the time, if you are using powered subs, I don't see the requirement of external amps.

For pure direct 2.0 CH big-tower systems in large rooms and/or very high volume, I do see the requirement for external high-power amps.
 
highfigh

highfigh

Seriously, I have no life.
Last time I shopped for the most transparent speakers I could find in the below $10,000 range I found them in a store in Toronto that powered the speakers with, surprisingly, class D amplifiers. In the end I bought the speakers without requesting them to try driving the speakers with my kind of trusted class AB amplifiers. I can't believe that was almost 10 years ago (in 3 days)!! So I think class D amps must be really ready for prime time now.

Incidentally, S&V asked the following question also about 10 years ago, so I think it is high time the question get asked again.

Are Class-D Amps Ready For Prime Time? | Sound & Vision (soundandvision.com)

For me, I have been planning on downsizing and I thought it would be good to do it before I cannot pick up amps that weigh more than 55 to 80 lbs in the box without much difficulty. At that point I had only ever auditioned the Bel Canto class D amps where I bought my last pair of the speakers that I intended to keep until the end. Of course I did buy other speakers (less expensive ones), after, even DIY the lovely BMR..:D

Then came the low cost Hpex and Purifi modules based miniature power amplifiers. Take a look of the potential gain in real estate for those using >200 W class AB amps:

View attachment 52446View attachment 52447

The Purifi amp is just slightly larger. So now my big and heavy Parasound amp's gone (the Bryston's long gone already).

Before I let the Parasound go I forced myself to listen to it for hours, just to be sure if I was really ready, and in the end I was. The Parasound really sounded sweet though for the last several days, subjectively of course.

I do miss my big class AB amps and I think I would keep my remaining ones for a long time, but I also love my new little toys. As a self proclaimed objectivist (converted many years ago), I don't want to comment on how their "sound" compared to my two much more expensive class AB amps and the remaining Marantz, Outlaw and Anthem amps other than to say they are all transparent to me but then it is based on my biased (because I know their specs, and some measurements) subjective impression only, without doing any serious level matched AB, let alone DBT.

The person who I passed my two amps to has purchased and received the necessary accessories for some more formal AB comparison listening tests between the Bryston and Parasound amps. I am hoping to bring my two little ones over too for more comparisons. They weight 6 to 8 lbs only so I could hand carry them easily.

I started this thread hoping to attract other new class D amp owners to share their experience.

For those interested, I bought my Hypex amp from Buckeye amps and the Purifi amp from VTV amps.

Buckeye Amps: New US based Hypex multichannel amplifier builder, line-up announcement! | Audio Science Review (ASR) Forum

VTV Amplifier – Pure Sound For the Ears

Buckeye currently only build Hypex amps based on the MP modules, VTV offers a much more varieties, including those from both Hypex and Purifi.

For Canadians on a budget, I think these two companies offer the best values. Shipping cost would be low for those in the GTA, as both are in Ohio.

Both are great to deal with, and would answer questions typically within 24 hours.

For warranty, Buckeye would send you a replacement module if you want to replace it yourself. It takes a few minutes to take it apart, should be easy to do.

Edit: Should have included the following links for those interested in Class D amplifiers:

What are the Different Types of Audio Amplifier Classes? | Audioholics
Bruno Putzeys: Head of the Class (D, That is) | Sound & Vision (soundandvision.com)
class-d-audio-amplifiers.pdf (analog.com)
How do Class D amplifiers work? | Rotel
Microsoft PowerPoint - class D tutrial_modified___2.ppt (irf.com)
Microsoft PowerPoint - Designing Class D Amp 2 B.ppt (irf.com)
Fundamentals of Class D Amplifiers | Maxim Integrated
Class D must read papers and publications | Audio Science Review (ASR) Forum
Audiophile Myths About Amplifier Negative Feedback Debunked | Audioholics
Is Too Much Amplifier Negative Feedback Bad? | Audioholics
Switching Amplifier (Class D) Basics | Audioholics
The Truth About Digital (Class D) Amplifiers | Audioholics
New NAD Masters Series Employ Revolutionary Class D Amplifier Technology | Audioholics
Cable Distortion and Dielectric Biasing Debunked - page 2 | Audioholics
Press - PURIFI (purifi-audio.com)
If Class D amps are so simple, why do they cost more than $1000?
 
Replicant 7

Replicant 7

Audioholic Samurai
If Class D amps are so simple, why do they cost more than $1000?
I was gonna say something about, why they cost so much, when you get so much less. Most of those Class D amps, weigh about the same as a cheap AVR's, 20 or less lbs. I've seen reviews on SVS subs where the class D amp has crapped out. That's why I asked about Class D amps reliability and longevity. Now I'm sure a bunch of Crown amp fanboyz will jump in and say, But Crown amps last. They'd be right also.
 
highfigh

highfigh

Seriously, I have no life.
I was gonna say something about, why they cost so much, when you get so much less. Most of those Class D amps, weigh about the same as a cheap AVR's, 20 or less lbs. I've seen reviews on SVS subs where the class D amp has crapped out. That's why I asked about Class D amps reliability and longevity. Now I'm sure a bunch of Crown amp fanboyz will jump in and say, But Crown amps last. They'd be right also.
If the SVS amps took a dump, I would like to see what failed. I have seen comments about plate amps failing because of vibration, but if that's the case, SVS (and anyone else whose amps crap out) should make them more durable- if they can send people into space, they someone should be able to make a plate amp that doesn't fall apart because of sound.

I think some Crown amps need a few features that would make them more usable for me, but if you haven't, check out the CDi and XTi models and their DSP abilities.
 
AcuDefTechGuy

AcuDefTechGuy

Audioholic Jedi
But will Class D last 10, 20 year's?
Good question. High quality Class-D operate significantly cooler and more efficient. So theoretically they should last 20YR, especially from ATI. :D

But then again, have high-quality Class-D amps been selling for 20YR?

If Bryston were to offer a Class-D would it get 20YR warranty?
 
lovinthehd

lovinthehd

Audioholic Jedi
Too early to tell with such as the Hypex or Purifi modules, they simply haven't been around very long yet. What has weight got to do with it? I haven't seen much about amp problems with SVS lately, think they had a bad run of amps a few years back, tho. Then again submitting an amp to the poor location in a sub isn't the best. Depends on quality used, too....rather have the amp external myself. Good design/execution will still matter, as it can with other classes of amps. None are particularly bullet proof, are they?
 
P

PENG

Audioholic Slumlord
No doubt there had been plenty of issues with class D amps. If it isn't the now seemingly much improved products such as the Hypex and Purifi, and some German chip amps becoming available and gaining popularity, I would not even have considered them. I am very happy with the two little Hypex and Purifi amps so far, as HD alluded to, only time will tell how reliable they are going to be. They have relatively low part counts, and cool running temperature, I think they will last just as long.
 
3db

3db

Audioholic Slumlord
No doubt there had been plenty of issues with class D amps. If it isn't the now seemingly much improved products such as the Hypex and Purifi, and some German chip amps becoming available and gaining popularity, I would not even have considered them. I am very happy with the two little Hypex and Purifi amps so far, as HD alluded to, only time will tell how reliable they are going to be. They have relatively low part counts, and cool running temperature, I think they will last just as long.
Running cooler with less parts count is a formula for longevity. Time will tell. The problem as I see it is that we are at an age group where 30 years from now could push us into senility and the whole dam thing becomes moot. :p
 
P

PENG

Audioholic Slumlord
Running cooler with less parts count is a formula for longevity. Time will tell. The problem as I see it is that we are at an age group where 30 years from now could push us into senility and the whole dam thing becomes moot. :p
True, for many of us. But some of us must have grand kids, and one of them may appreciate a 15 years old little class D power amp that could be expected to last even another 5 years.:)
 
3db

3db

Audioholic Slumlord
True, for many of us. But some of us must have grand kids, and one of them may appreciate a 15 years old little class D power amp that could be expected to last even another 5 years.:)
Speaking of which, I have a new grandson born on Valentine's Day. :)
 
N

NMG

Enthusiast
I’d definitely consider them but it would have to be in the ballpark of an AB amp price wise for me. I see the advantages for sure, but I also don’t mind having a big heavy box sitting on my cabinet :)
 
G

Golfx

Full Audioholic
I’d definitely consider them but it would have to be in the ballpark of an AB amp price wise for me. I see the advantages for sure, but I also don’t mind having a big heavy box sitting on my cabinet :)
I believe you will find they are quite competitively priced if not routinely cheaper when compared to similar quality/wattage Class AB amps.
 
Replicant 7

Replicant 7

Audioholic Samurai
I've got one that's over 10 years old and it works just like it did when I bought it used in 2011.
They should, I have a good friend who D-J's on the side for cash. All he uses is Crown amps, can't killem.
 
P

PENG

Audioholic Slumlord
I've got one that's over 10 years old and it works just like it did when I bought it used in 2011.
You are the first one (that I know of) who have used it long enough to comment on the reliability of class D amp. Would you mind telling us what make it is, manufacture year, and usage (lightly used, daily, weekly etc..)in general, please..
 
newsletter

  • RBHsound.com
  • BlueJeansCable.com
  • SVS Sound Subwoofers
  • Experience the Martin Logan Montis
Top