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Valve pres with solid state powers , what works

DavidS

pfm Member
As title , there are many combinations that don't work because of impedance mismatching.

Any experience of this ?
 
what is solid state, damn kids and their new fangled technology.
 
My experience is that 'fannying about' causes audiophiles far more worry and displeasure with their systems than just leaning back and enjoying the music. The whole notion of liking valve amps is a visual thing, nothing more. Amps are either good or they're not: there is no 'sound' to specific topologies so the notion of valve pre-solid state power is just an attempt to be able to drive speakers because valve power isn't enough, or to try to introduce distortion to the equation because the listener is not happy with a distortion-free sound. There's absolutely nothing wrong with liking a bit of distortion whatsoever but there's many a system gone belly-up because of mismatches caused by meddling!
 
A friend of mine had a kit made of a Conrad Johnson PV 10/Bryston 2B flat version hooked up to some DCM time window speakers and it sounded bloody well right for an affordable vintage setup.
 
If the right valve pre amplifier came along I'm going to give it a go with a sugden a21. Really looking into starting to treat my room acoustically at the minute though so valve pre on back burner for now.
 
In many ways it's an impossible question to answer as for many people the last thing they want is for it to be good.
A perfect pre amp has no sound of its own. Most who want to add a valve pre to a SS power want to ruin the sound by adding "nice" distortion and in many ways and many circumstances having a bad "match" will "help" this!!
 
The increasing hassle with valve preamp's comes if you are tempted, or intend all along, to "play" with the valves.

When I looked recently, I could not believe how much NOS and used valves have increased in price since I was buying nearly two years ago, and I can't imagine that prices will be levelling-out either.

NOS ECC82 were mostly something like £10 each and "unfashionable" brands were no more than a fiver. Even Philips, including Mullard, were under £20 if you chose wisely what to bid on.

Tempted? Buy now, or pay a hell of a lot more in the none too distant future.
 
I really don’t care what the tub-thumpers, trolls, shills or agenda-posters think but for me, and that is all that matters in this equation, it is only since having at least one valve between me and a digital source that I have grown to really love it as much as vinyl. I have two systems in regular use, one has a very good valve preamp, the other a very good valve power amp. I now absolutely love (well mastered) CDs!

If a system gets you playing music it is working. Always listen and decide for yourself. There really is nothing more to it unless you are trying to sell/shill something!
 
In many ways it's an impossible question to answer as for many people the last thing they want is for it to be good.
A perfect pre amp has no sound of its own. Most who want to add a valve pre to a SS power want to ruin the sound by adding "nice" distortion and in many ways and many circumstances having a bad "match" will "help" this!!

I went from Audiolab 8300MB and Farlowe era pre', changed to Avondale NCC220, changed to Croft Micro, changed to Croft Super Micro.

Each change brought greater clarity, greater precision, greater depth to the music, and the changes were easy to hear - I have an unbiased guinea-pig to judge.

Did the valves bring distortion? To be honest, the changes for the better swamped anything else that my ears may tell/told me, and what the speakers produce, the ear collects and sends to the brain, and what the brain interprets that as, are all, very, very different.
 
Personally I'm against valve rolling.... Even though I do it here and there myself! Most of the time all you are doing is slightly changing the operating characteristics of the stage. ie it's not so much that different makes of valve sound different and more that specific samples draw slightly different current etc and so have small changes in the load line and changes in the amount and nature of distortion. Changing resistor values in the stage by a few percent would often have the same effect... but hey if you've got a box of suitable valves it is easier and more "fun" to just try different makes I guess.... it really goes against the grain as an EE though!
 
I went from Audiolab 8300MB and Farlowe era pre', changed to Avondale NCC220, changed to Croft Micro, changed to Croft Super Micro.

Each change brought greater clarity, greater precision, greater depth to the music, and the changes were easy to hear - I have an unbiased guinea-pig to judge.

Did the valves bring distortion? To be honest, the changes for the better swamped anything else that my ears may tell/told me, and what the speakers produce, the ear collects and sends to the brain, and what the brain interprets that as, are all, very, very different.

Yes.... well the lack of NFB and no doubt excessive loading of the valve stage did. More than that of the other gear anyway.
People are far too quick to ascribe changes/improvements/reductions to sound quality to whatever their personal hobby horse is at the time! Pre amp A sounds better than pre amp B to you and A happens to be valved and so you say "it is a better pre because it is valved"....

As I said above, and will keep saying, the best pre amp is one with no sound of its own... "a straight wire with (or without!) gain". This is the raison d'etre of hi fi itself. Reality. Not "niceness".
 
Yes.... well the lack of NFB and no doubt excessive loading of the valve stage did. More than that of the other gear anyway.

Serious request - please explain a bit - I don't think I read that comment as you wrote it and meant it to read. "Excessive loading" in particular.
 
As I said above, and will keep saying, the best pre amp is one with no sound of its own... "a straight wire with (or without!) gain". This is the raison d'etre of hi fi itself. Reality. Not "niceness".

Reality? What is that?

A preamp that "does nothing" would be ideal if "perfection"/"reality" was fed into it.
The problem there is that DACs sound different, as do turntables, tonearms, cart's, and phono stages etc. etc. etc.. So why pick on the pre'? It applies, or should, to all components, equally.

I am not necessarily after reality (or "niceness") either. I am after a set of kit that produces an enjoyable, engaging, believable experience across a very broad selection of recorded music.
 
Serious request - please explain a bit - I don't think I read that comment as you wrote it and meant it to read. "Excessive loading" in particular.

Just what I've said several times before... that triode valves are not inherently high distortion. They are lower than transistors in fact. It's the lack of stages and NFB that causes most valve pres to have higher distortion than SS ones. An Audio Research SP8 line stage for example has THD down around 0.003% and output impedance of a few Ohms.
As I explained in the Croft 25 thread the other day it has fairly high Zout and very little load driving ability (many Audionote ones are worse still) and hence when driving something like a naim amp (and probably the Avondale you mentioned) the 22k load is enough to raise THD from about 0.02 to 0.5%.. hence you could say a bad match... but the 0.5% of mainly second harmonic is likely the reason many want a valve pre in the first place! "valve warmth" and all that...

Valve pre's using a cathode follower will usually have pretty low distortion and lower output impedance.
 
^^^^Thanks. One of these days that will all sink in and stay in.

I have ordered copies of both books mentioned on the DIY valve thread and will read and understand the basics if it is the last thing that I do.
 
Obviously, again, there is far from a simple answer, but modern SS power amp's have input impedance values of 20K and thereabouts, as you have said, but what would most valve pre's be happier with? OK, more, but realistically?

Where were/are valve power amp' input impedances pitched? That is assuming that they are aimed at operating with a valve pre'. Or is the "matching" achieved between valve pre' and power achieved in some other way?
 
If I had the money, I might be tempted to settle on a Mcintosh MA 352 to scratch that itch. Not for everyone, of course.
 
I use a valve preamp to drive my diy Voyagers via eight metre leads. Sounds absolutely fine to me. I use another similar valve preamp to drive a Crown PSA2 or NCC200s in my office system. I've tried a few SS preamps and not liked any of them. I tell a lie, I did quite like the old MF Pre3a I had but it was a touch noisy.
 
I use a valve preamp to drive my diy Voyagers via eight metre leads. Sounds absolutely fine to me. I use another similar valve preamp to drive a Crown PSA2 or NCC200s in my office system. I've tried a few SS preamps and not liked any of them. I tell a lie, I did quite like the old MF Pre3a I had but it was a touch noisy.

I don't doubt that, and doubt that anyone else would either, I certainly hope not. The point, maybe not what you are alluding to perhaps, is that what we like is not necessarily "as nature intended", that is, not like real instruments and human (or other) voices, and very frequently it is not even especially close.
 


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