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Class A Amp

I made my mind up to do it this time, or to die in the attempt. If it isn't guaranteed to scorch my fingers, I'm not going there.

Short list, so far :

1. a Sugden A21, either the current generation, or the one immediately before.

2. a Pass-clone, the Aleph 3 sounds very interesting

3. secondhand Krell, but taking on board Arkless's warning about refurbishment costs, this is probably over budget

4. a Marantz PM4

I refuse to consider anything valved. I'm adamant about that. Completely certain. Not to be deflected, though obviously I would prefer EL34 output devices .... unless I could afford SE triode.

Now for the tricky bit. Finding one.

Disparate to say the least! Like saying your next car MUST be diesel and then having a 1100 Dacia and a 5 litre 7 series BMW on the same short list cos they're both diesel versions!

Most <30W valve amps are class A BTW and some at much more than that. They can sound fabulous. Personally I'd have little interest in what type of output valve was used beyond implications in reliability and replacement costs... but I wouldn't have a SE triode amp even if it was free!

If a secondhand Krell is working well enough then it could still be worthwhile if you get it at the right price and you have the prospect of improved performance after it is sorted out.

I wouldn't bother with the Marantz PM4. nice enough but not in the same league as the others.
 
Disparate to say the least! Like saying your next car MUST be diesel and then having a 1100 Dacia and a 5 litre 7 series BMW on the same short list cos they're both diesel versions!

Most <30W valve amps are class A BTW and some at much more than that. They can sound fabulous. Personally I'd have little interest in what type of output valve was used beyond implications in reliability and replacement costs... but I wouldn't have a SE triode amp even if it was free!

If a secondhand Krell is working well enough then it could still be worthwhile if you get it at the right price and you have the prospect of improved performance after it is sorted out.

I wouldn't bother with the Marantz PM4. nice enough but not in the same league as the others.

My comment on valve amplifiers was intended to be whimsical. I'm not considering one! Your comments on the Marantz tend to confirm my suspicion that this is a lesser choice, purely based on its value in the s/h market.

I have in the past heard the A21, and really liked it. It's the less ambitious, but perhaps less demanding choice. The Krell and the Pass I'm trying to evaluate from a position of unimpeachable ignorance. It hardly helps that I live out in the wilds of Scotland.

One thing I certain of - I would not be permitted to own a Series 7, or any other BMW, as I know how to drive.
 
I used to own a Krell KSA-150. Sounded great. Weighed a TON! Unnecessarily heavy and difficult to deal with. Lots of heat, too.
Since I moved from the cool mainland USA to Hawaii, the Krell has been replaced. I use a Sony TA-A1ES, a hybrid class A amp which sounds *better* than the Krell, in my opinion. Much less expensive, much less heavy and a little less heat. I also use a Peachtree amp500 which is class D and it also sounds excellent, almost as good as the Krell, I’d say, for a lot less money, less weight, and much less heat.
Class A sounds great, but there are disadvantages and there are some pretty good alternatives, too.
I live in Scotland. Any extra heat is generally very welcome!
 
There is also the Schiit Aegir too, it's not very powerful, but ive been thinking about get a pair and using them as Monoblocks. $799 or £800.... i like the way the price isn't quite a strait Dollar to Pound conversion... ;/

https://www.schiit.co.uk/Aegir

https://www.stereophile.com/content/schiit-audio-aegir-power-amplifier

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I considered the M-22 too especially after watching this...

But in the end decided I didn't fancy the hassle of vintage gear (funnily enough that guy who reviewed it, his M-22 crapped out just a couple weeks after that review)
Which is why I said:

The Pioneer M-22, on the other hand ... is fabulous. But will need a good fettle and checking over, if the OP can find one in the first place.
The M-22 I bought had to be fully rebuilt with all caps (except the the four monster 33,000uF cans), non-original power transistors replaced with a full set of super-rare genuine Sanken, trim-pots, diodes etc. changed. I recognised that heat remains the #1 enemy of longevity, so I built a platform with a pair of twin fans that run at a low speed keep air flowing through the chassis (bottom plate is perforated). Ordinarily, the heatsinks would be too hot to touch for more than a few seconds once it has reached full operating temperature. Now, it stays at around 50 degrees Celsius, and I'm assured that the rectification circuit where power diodes run hot are bathed with fresh air.

Vintage gear certainly needs more TLC, but the rewards of arguably the finest sounding amplifier I've ever owned, is worth the effort. If my M-22 should become impossible to service, then it'll be another class-A amp that I'll be buying. At this stage, Luxman or Accuphase are the likely contenders for me.
 
I’ve always used Sugden amps since 1975 and they all get bloody hot but never have I had one actually break down, the nearest being a noisy volume pot and I live in the Canaries where the switch on temperature is invariably 20 degrees or more so being an absolute ignoramus when it comes to electronics all I can say is that someone at Sugden certainly knows how to choose their components.
 
There is also the Schiit Aegir too, it's not very powerful, but ive been thinking about get a pair and using them as Monoblocks. $799 or £800.... i like the way the price isn't quite a strait Dollar to Pound conversion... ;/

https://www.schiit.co.uk/Aegir

https://www.stereophile.com/content/schiit-audio-aegir-power-amplifier

919sch.promo_.jpg


919sch.ins.jpg
They do look interesting (the Vidar too). My only problem with the design is they mention a microcontroller controlling all sorts of things (bias included), rather than using passive components or manual calibration. This makes me wonder how it will behave if/when the microcontroller fails down the line, and if anyone will be able to fix it. Assuming Schiit hangs around a long time and keeps lots of spares, maybe it's not a realistic problem.
 
They do look interesting (the Vidar too). My only problem with the design is they mention a microcontroller controlling all sorts of things (bias included), rather than using passive components or manual calibration. This makes me wonder how it will behave if/when the microcontroller fails down the line, and if anyone will be able to fix it. Assuming Schiit hangs around a long time and keeps lots of spares, maybe it's not a realistic problem.

Yes I'm not sure either with it being an American component (made in the state too), everything is one board to save costs, there is a five year warranty on them apparently, the guy that runs the company seem very pragmatic and honest which is something i suppose.

I’ve always used Sugden amps since 1975 and they all get bloody hot but never have I had one actually break down, the nearest being a noisy volume pot and I live in the Canaries where the switch on temperature is invariably 20 degrees or more so being an absolute ignoramus when it comes to electronics all I can say is that someone at Sugden certainly knows how to choose their components.

Thats a brilliant endorsement, and of course if something did go wrong it could be be fixed easily. I've just read their tag line on their website... Sugden - Rescuing Music from Technology. I'd say that's a summarisation of those that have tried the all singing and dancing packed full of technology, Class D amps and while initially exciting, they have eventually been found wanting in terms of enjoyment.
 
Yes I'm not sure either with it being an American component (made in the state too), everything is one board to save costs, there is a five year warranty on them apparently, the guy that runs the company seem very pragmatic and honest which is something i suppose.
I'm assuming this comment means you're from the UK? Not everyone is, I don't think it really makes sense to have more or less confidence in a company's longevity based on its location.
 
No matter the comments, specs, graphics, energy consumption and being non environment friendly, nothing beats a real pure class A for listening pleasure over long periods of time.
The best compromise for me is a decent class A/B that sounds good enough for me but can generate more power.
Never been impressed by the other/new technologies so far.

For me a good sounding amp is a good sounding amp, and whether it's class A, A/B or something else doesn't seem to make that much difference to me. Of the amps I mostly listen to at the moment one of them is class-A (an Audio Note integrated), one is class A/B (a Krell integrated) and the other is class D (a Primare integrated) and all of them sound good to me, and are great for long term listening. I like all of them but the Krell is my favourite amp.
 
I've been looking at Joe Henry's Pass-like amps on eBay, of which I have heard good reports. Anyone care to recommend one in particular? What other Class A amps are out there? I heard the previous model Sugden A21a which sounded very well to me. Budget - tops -£1200, preferably less, as I like to eat once in a way.

Choosing which First Watt-type (from JH) was a bit tricky. Personally went with the M2 as it appealed in SQ descriptions and design concept. So a bit of a stab and I've not heard any others to compare it to, but it sounds wonderful in itself - moreover, as I'd come to hope.

In terms of getting an idea of the various First Watt products, his own website is obviously good and makes some comparisons in the respective manuals (http://www.firstwatt.com/prod.html). Six Moon reviews have a go at that also.
 
I finished my BA2018 preamp (designed by Wayne from Pass Labs) yesterday. Today was the first time using both it and the F5. They sound fantastic together! However, as I suspected, they won't be sticking around. This was my first time owning/using a class A amp, and it gives off too much heat. I ran it for a few hours and it raised the room temperature a few degrees, which meant running fans to stay comfortable. On many days it would mean more AC!

So I think I need to find this setup a home up north where the heat would be welcome. Valencia is still in the 80s and I don't think we'll be needing any heating until at least December!

It's too bad -- I also built the Pass M2X amp boards to compare but what's the point if the amp isn't staying? :(

A really nice thing about the DiyAudio based clones is the amp boards are modular -- the same chassis/PSU can have the amp boards swapped out. Once you have one of them you can very affordably swap out the boards and try the F4, F5, F6, M2X (which has six daughter boards to play with), Aleph J, etc...
 
Schitt do a range or Preamps too, so i suppose they'd be a good match, seems like a interesting product if your speakers are sensibly sensitive, get's a smashing write up in Stereophile.

(I'd use my own Minimax Preamp into them)
Aren't all the (non-trivial) preamps valve based? I was surprised to see nothing solid state other than the $49 passive pre.
 
Schitt do a range or Preamps too, so i suppose they'd be a good match, seems like a interesting product if your speakers are sensibly sensitive, get's a smashing write up in Stereophile.

(I'd use my own Minimax Preamp into them)

Thanks. I read the Stereophile piece and might be tempted in the future.

Jack
 
Aren't all the (non-trivial) preamps valve based? I was surprised to see nothing solid state other than the $49 passive pre.

I'm not sure really i'm not Schitt expert! (although others would disagree), i just read the review on Stereophile and the John Darko's little film about them and thought they were good value for money, i did have some Monarch monoblocks that were Class A at one point but never really had much chance to try them.

Are you in Valencia California, or Spain Booja?
 
I'm not sure really i'm not Schitt expert! (although others would disagree), i just read the review on Stereophile and the John Darko's little film about them and thought they were good value for money, i did have some Monarch monoblocks that were Class A at one point but never really had much chance to try them.

Are you in Valencia California, or Spain Booja?

¡España!

I'm not a Schiit expert either. I just noticed on the website all the preamps over $50 had tubes sticking out the top.

Someone's going to have a fit that I called it a tube. But you know, I don't call TP bog roll either. :p
 


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