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Old 11th February 2009, 06:19 PM   #11
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Quote:
Originally posted by cygnus x1
Andy,
I tried all the others, 01, 26, 1H4, 1H5, 1J6, 10, 45, 801, 811, etc. The CX-340 really sing with the right PS and parts. For years I ran it with a Lambda Tube regulator and all kinds of LC networks, CCS etc. It really improved with the Salas HV shunt reg.
I think I tried all those on your list except 1H5, but also added 3a5, 1G4, 30, 31, 12A, X99, 1E4 and a few more. Never came across the CX-340. I'll have to look out for it. I also have some European ones to try like RE074, RE034 and RE134.

I must look at the Salas. I've been using a mesh plate AZ1 with choke and polypropylene caps.

andy
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Old 11th February 2009, 06:53 PM   #12
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Quote:
Originally posted by SY
There's a well-known designer for whom I have the greatest respect who believes (not unreasonably) that much of the attractive "vivid" quality of DHT comes from the mechanical resonance of the cathode.
I think this is exactly right. However, the best sounding thing I have ever produced is a 71-A based headphone amp. It is lovely to listen to. I am never concerned that there are musicians in the room, however. The notion that a stereo will ever depict realism, or indeed even come close, is a fallacy.

As such, the goal to me is to produce something that sounds good and that evokes the emotion of the music, not something that reproduces some situation in my house. Really, the "distortion" between a live event and a recording is huge -- the same as a distortion between a photograph and an experience. It is dumb to even compare.

Quote:
Originally posted by andyjevans
So my line of reasoning is:
"If this is added realism and vividness, then by what fortuitous accident does it get closer to the timbre of acoustic instruments than IDHTs do?". * * *

Do you see my difficulty with this line of reasoning?
Sure, it is predicated on the belief that either the DHT or IDHT has a chance of sounding real, at all. If one sounds better to you than the other, why does it need to do more?


Quote:
Originally posted by tubelab.com
I prefer Zeiss,
Me too, for exactly the reason I prefer DHTs, oddly enough.

Quote:
Originally posted by tubelab.com
Remember the original Kodachrome advertising stated that Kodachrome delivers pleasing color rendition, not accurate color rendition. Worked well for Kodak.
The analogy is apt. I love Kodachrome, too.

Fwiw, I say that good solid state sounds like Velvia looks
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Old 11th February 2009, 07:04 PM   #13
Sheldon is offline Sheldon  United States
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Quote:
Originally posted by andyjevans
"If this is added realism and vividness, then by what fortuitous accident does it get closer to the timbre of acoustic instruments than IDHTs do?"
I think confusion and friction often arises because terms like accuracy and realism are not defined in context. SY is referring to accuracy of reproduction, and it can be defined objectively. "Realism", as used here, refers more to the effectiveness of the illusion. Not saying that's inferior or undesirable, as one cannot accurately reproduce all the sounds that would reach our ears, with all the correct timing in in the right proportion, and with all the correct directional cues. So we make do. Case in point: I never hear the some kind of directional cues live that I hear in a stereo recording, especially with large ensembles. But, in the live event, I have my eyes and the venue effects to add to what I hear. So is a good recording accurate? Well, only the recording and amplification chain can be accurate. Once it hits the speaker and goes into the room, it's not. So if the system adds a little here or there to fill in some of the missing pieces and create a more realistic seeming illusion, then great. But, the illusion that triggers the "real" in you, might not be the same one that works for others.

DHT's are certainly no more accurate than IDHT's, as a class. But perhaps they can they add something that enhances the illusion for at least some. SY suggests a mechanism.


Quote:
Originally posted by andyjevans
Maybe there are other factors at work here?
OK. Such as?

Sheldon
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Old 11th February 2009, 11:29 PM   #14
Vlauga is offline Vlauga  Russian Federation
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Quote:
Originally posted by analog_sa



I suspect the "DR" makes a real difference.
Yes, you are right.
Modern 6N30 = ~6N6P with not so good sound.
The old Soviet 6N30P-DR absolute no equivalent of modern 6N30P. 6N30P-DR has powerful and at the same time refined and transparent sounding.
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Old 12th February 2009, 12:52 AM   #15
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Quote:
I build circuits to sound good, so my ears are the arbitor of what stays and goes.
I have an inherent distrust of my ears. Actually, not so much my ears as my brain, to which my ears are connected.

If they are more accurate(meaning that they produce a scaled up version of the input and nothing more), it should be easy to provide some evidence of this in the form of measurements. Don't get me wrong, I'm not saying that they aren't more accurate. I'm just saying that it sounds like a cop-out to say on one hand that they are more accurate but on the other hand that one will only accept one's own listening experiences as evidence of their accuracy, which I hear all the time.
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Old 12th February 2009, 01:05 AM   #16
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Default Re: Is it worth using anything other than DHTs for preamps?

Quote:
Originally posted by andyjevans

Clearly the preamp stage is critical - it establishes the sound that then gets amplified through the chain. Lose something and it's lost.
...
All my experience over 2 years has shown me that I just can't get that vivid, alive, delicate sound with IDHTs, whatever they offer. I'm a professional musician - I've played all my life in orchestras, small groups, theatres, clubs etc. I know what real instruments sound like, and I get this with DHTs.
...
andy evans
The only IDHT that has come close to capturing the magic of DHT preamps was based on the 27 tube (mesh plate globe 27s).

-- josť k.
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Old 12th February 2009, 01:12 AM   #17
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How about some links to schematics of the pre you are talking about?

Fran
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Old 12th February 2009, 01:24 AM   #18
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Quote:
The only IDHT that has come close to capturing the magic of DHT preamps was based on the 27 tube (mesh plate globe 27s).
I just recently found a mesh plate globe 27 in a local antique shop for $1. I bought it, of course.
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Old 12th February 2009, 01:33 AM   #19
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Quote:
Originally posted by woodturner-fran
How about some links to schematics of the pre you are talking about?
Fran
Here you is:

27 Parafeed Preamp
http://nullspace.us/27.html

Click the image to open in full size.

Enjoy,

-- josť k.
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Old 12th February 2009, 01:51 AM   #20
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DHT's are certainly no more accurate than IDHT's, as a class. But perhaps they can they add something that enhances the illusion for at least some>>>>>

I believe I'm saying that as far as I can hear, DHTs ARE more accurate in terms of timbre, and are so as a class. I'm not talking about illusion either, like situating speakers in such a way to create a "soundstage". And I think a good sound system can come quite close to live instruments. I'm only talking acoustic instruments here - nothing miked up or amplified. Such instruments as drumkits, oboes, clarinets and Steinway pianos have quite distinctive sounds, and I think musicians who hear such sounds on a daily basis and in close proximity can recognise when the timbre of these instruments is close or closer to the original.

The bit I personally have diffidulty with is that in the recording chain there are God knows how many solid state devices and transformers. So the difficult part is believing that a recording can go through all that lot, and when it encounters a single preamp DHT somewhere in the chain the sound reverts to a more realistic timbre.

Against that, I have found that if I replace all the tubes with DHTs - preamp and amp - the timbre gets better and better.

So I'm still stuck over the theory here, even though I can hear the results quite plainly.

andy
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