Class D amplification - Shock!

[John_73]

I've in recent years moved from Quad 606II to Primare A30.2 to Primare A34.2 (proprietary class D) and in every case it's been a significant improvement as far as my ears hear it. The A34.2 gives more detail, sound stage and better instrumental timbral information. I'm pleased.

Interesting. I’m planning on moving on from my Quad 606 and (assuming I find a buyer for my Chord Hugo TT2) going for either a used Benchmark AHB2 in tandem with a Dac3 HGC, or the following, which contains the Purifi amplifier modules which ASR recommended highly recently. Looks pretty good value too:

https://www.audiophonics.fr/en/powe...ass-d-stereo-purifi-2x400w-4-ohm-p-14393.html

 

[James]

I s'pose that it's experience of going from valves to s/s class A rather than from class B or A/B. Can't seem to find any info. on that one.

Mike, unfortunately I have no experience with valve (power) amps, so I'm not in a position to comment.

 

[Hayche]

My leema elements intergrated is a class d keeper for me. It just plays music the way I think it should be played. Second hand bargain too!

 

[htm_1968]

I s'pose that it's experience of going from valves to s/s class A rather than from class B or A/B. Can't seem to find any info. on that one.

I use two types of Class A amp. My speakers are relatively efficient at 91 dB/w at 1 metre. The day-to-day amps are Pass Labs XA100.5 monoblocks, which are rated at 100W in Class A. The only downside to these (once they are in situ) is that they throw off a lot of heat. In very warm weather I use a pair of thermionic Rank Concept monoblocks which are rated at 16W. I'm definitely not keen on a lush 'valvey' sheen.

Below is a photo is the Ranks in action. That is a 12" record mailer protecting the casework on the Pass Labs amp.

The real trade-off between the two set ups is (for want of a better description) the loss of a bit of bottom end welly from the Ranks. They run hot, but nowhere near the Pass Labs in terms of heat. Ultimately it is a question of trying a few alternatives so a bake-off would be the obvious suggestion were it not for CV-19.

 

[Mike Reed]

Ultimately it is a question of trying a few alternatives so a bake-off would be the obvious suggestion were it not for CV-19.

Indeed; nail on the head. I've been invited to hear my friend's recent new purchases: a 12" Glanz arm (£6K?) plus Miyajima Shilabe (£3K?) into his system which is v. similar to mine (E.A.R. integrate. + Quad 2812s v. my 912/509s + Quad 2905s). Probably okay, as we're both sensible but think I'll wait a while.

Re. class A, the Rank is valved but low-powered but is the Pass Labs valved or s/s class A? No wonder there's a discrepancy in 'welly' (and the rest, probably ?) between your two amps, even considering the sensitivity of your speakers. My 509s are 100 W/ch too, but oddly, don't get overly hot or eat that much juice; seems T de P's designs, and possibly use of valves, are known for that. Mind you, mono's may well make this claim null and void !!!!

Looking at your Pass Labs, I think this might be s/s, which is why you think this is a viable comparison. 100W of s/s class A is one hell of a lot!!!!! Compare Vitus and Sugden around 30/35 watts!

Thanks for that; very interesting. Bit of a monster, that Pass Labs; understandably with that kind of power output.

 

[misterdog]

going for either a used Benchmark AHB2

Good luck finding one of those, you may also have competition from myself.
In the US they are $3000 new and $2500/2700 second hand.
Here the retail has risen to £ 3495, I suspect due to the plummet of the £ v $ in May, now the £ is strong will the RRP drop ?

Generally as rare as hens teeth. In the US Benchmark offer a 30 day trial, shame that is not available here.

 

[htm_1968]

Indeed; nail on the head. I've been invited to hear my friend's recent new purchases: a 12" Glanz arm (£6K?) plus Miyajima Shilabe (£3K?) into his system which is v. similar to mine (E.A.R. integrate. + Quad 2812s v. my 912/509s + Quad 2905s). Probably okay, as we're both sensible but think I'll wait a while.

Re. class A, the Rank is valved but low-powered but is the Pass Labs valved or s/s class A? No wonder there's a discrepancy in 'welly' (and the rest, probably ?) between your two amps, even considering the sensitivity of your speakers. My 509s are 100 W/ch too, but oddly, don't get overly hot or eat that much juice; seems T de P's designs, and possibly use of valves, are known for that. Mind you, mono's may well make this claim null and void !!!!

Looking at your Pass Labs, I think this might be s/s, which is why you think this is a viable comparison. 100W of s/s class A is one hell of a lot!!!!! Compare Vitus and Sugden around 30/35 watts!

Thanks for that; very interesting. Bit of a monster, that Pass Labs; understandably with that kind of power output.

Sorry Mike, I wasn't clear. The Pass Labs Mono's are 100W in pure Class A solid state. They are huge, fugly, immensely heavy, expensive to buy and run and totally impractical. OTOH, they sound wonderful.

 

[notevenclose]

My point is that I am now interested in hearing hi-fi quality Class D amps after wiping my prejudice away in a stroke.

I think we're probably at the stage where there are good and not so good amps of all types.

I've long said I'm technology agnostic in that I don't care how it works or whether it glows in the dark or not. In the last 20 years or so I've owned amps by Sugden, Lavardin, Kondo, Leben, 47 Lab and Job, and each one was the best amp (or at least the best I could afford) for the task at hand at the time.

I've no experience of Class D in a known system, but I'm being threatened with one potentially arriving in the not too distant future, so who knows?

 

[Gervais Cote]

Sorry Mike, I wasn't clear. The Pass Labs Mono's are 100W in pure Class A solid state. They are huge, fugly, immensely heavy, expensive to buy and run and totally impractical. OTOH, they sound wonderful.

I think pure class A has been specifically designed for the human ears (or maybe the other way around ?) but most of people don’t want to admit that fact.
When I give a listen to that kind of amp, I don’t read the reviews or look at the specs or graphs as they all become irrelevant after 30 seconds of music listening ! IMO.

 

[notevenclose]

I think pure class A has been specifically designed for the human ears (or maybe the other way around ?)

Sugden have been refining the original a21 design for over 50 years, but I'm reasonably confident even the most feverish Creationists would concede that we have lots of evidence for the existence of lugholes even before Heckmondwicke's finest swung into action.

 

[John_73]

Good luck finding one of those, you may also have competition from myself.
In the US they are $3000 new and $2500/2700 second hand.
Here the retail has risen to £ 3495, I suspect due to the plummet of the £ v $ in May, now the £ is strong will the RRP drop ?

Generally as rare as hens teeth. In the US Benchmark offer a 30 day trial, shame that is not available here.

I’ve seen a few go for around £2200 this year, and have been very tempted, but really need to sell on a few other things first.

 

[Mike Reed]

They are huge, fugly, immensely heavy, expensive to buy and run and totally impractical. OTOH, they sound wonderful.

Having a deck which fulfils the 'fugly', heavy' and in a logistical sense, 'impractical' as well as 'wonderful'(N.A.Dais), I empathise. However, class A s/s can't be more juice-hungry than valves, surely? Wonder if they have toroidal or the older type of trannie as in most valved amplication.

 

[Arkless Electronics]

Having a deck which fulfils the 'fugly', heavy' and in a logistical sense, 'impractical' as well as 'wonderful'(N.A.Dais), I empathise. However, class A s/s can't be more juice-hungry than valves, surely? Wonder if they have toroidal or the older type of trannie as in most valved amplication.

It entirely depends on the power output (and on what type of class A but that's another topic) but for equal power valves will take more juice due to that needed for the heaters in the valves. However, more output power will quickly make up for and then go beyond that! ie a 20W class A valve amp would give something like the same heat as a 30W SS class A but a 50W ss class A would give off much more heat than either (and of course use more juice).

 

[Dirkster]

At a lower price point, the PS Audio Sprout100 integrated amplifier is a great-sounding Class D unit. About $700 in the US, don’t know about UK availability/pricing. I bought one a few months ago, I’m still waiting on a pair of Dynaudio Emit M10 speakers, so in the meantime I’m running a pair of inexpensive ELAC Debut 2.0 B5.2 speakers and the setup sounds shockingly good.

Given the fact that the nearest hifi shop is at present, an international flight away from my current home, I've taken a punt on a Sprout100. It should hopefully be with me before the end of the month.

Once again, many thanks for all of your advice. It is gratefully received.

Full listening report to follow.

 

[Linus]

At a lower price point, the PS Audio Sprout100 integrated amplifier is a great-sounding Class D unit. About $700 in the US, don’t know about UK availability/pricing. I bought one a few months ago, I’m still waiting on a pair of Dynaudio Emit M10 speakers, so in the meantime I’m running a pair of inexpensive ELAC Debut 2.0 B5.2 speakers and the setup sounds shockingly good.

I have a pair of the Dynaudio Emit 10, and though I’ve now mainly been using Proac Tablette 10’s, I think the Emit 10’s are great. I hear the Emit 20 is even better. Great value.

 

[JemHayward]

I lent a Muse class D amp (about £30 on Amazon a few years ago) as he wanted to try 5.1 sound from his Arcam pre-power system. He needed another power amp to drive the rear speakers, but when I went round to listen, it sounded a lot better than it had in stereo a few days before. We swapped back to stereo, and it still sounded much better. Then he remembered to tell me he was using my Muse as his main power amp, and the Arcam FMJ to drive the rears as it sounded much better that way around.

 

[Subito]

FWIW, the Emit 10 seems perpetually out of stock at my preferred US dealers, so I took a chance on the new ELAC Uni-Fi 2.0 UB52 bookshelf models (just released Sept. 1st). They only arrived two days ago, and already I am utterly stunned at their sound quality. They deliver a combination of startling clarity, midrange smoothness, enormous soundstage and bass power & definition I didn’t think possible at this price ($600/pr US).

My favorite CD for months now has been Ry Cooder’s “The Prodigal Son,” and I have listened to it dozens of times recently. When I first played it through the UB52, it was like hearing it for the first time, his vocals were so much more lifelike and intimate, with none of the slight harshness I had heard before. The breadth and depth of the soundstage made the performances feel much more immediate and present. Bass notes are deep and powerful, but more importantly they’re crisp, clear and rhythmically exciting.

I could go on and on, but you get the point. In the US there are dealers like www.crutchfield.com that give 60 day home trials on speakers, and they can typically be shipped back for only $10, so I would encourage anyone in the market for affordable bookshelf speakers to check out the UB52. For me, I am now officially done. For $1500 total (Sprout100 at $699, ELAC UB52 at $599, B&W Stav24 stands at $199) I have put together a system that makes listening to music a deeply and consistently enjoyable experience.

 

[Iain Docherty]

I have a pair of the Dynaudio Emit 10, and though I’ve now mainly been using Proac Tablette 10’s, I think the Emit 10’s are great. I hear the Emit 20 is even better. Great value.

I had a pair of Emit 20s in my second system for a while and they were really, really good