Your all time favourite tube pre

[Learner]

Hi guys,
Just out of curiosity, I was wondering if anyone could nominate your all time favourite tube pre(mic or line) that you have used?

I am looking to experiment with all nominated tubes aiming to find out and try to understand factor(s) that contribute to the audible perception, which causes the "pleasant/positive" listeing experience.

Schematic on the tube biasing would be greatly appreciated but not essential, thanks in advance!

 

[CJ]

You mean besides an EF804S?

Maybe something from the same family. That would be first place for me. But I have tried not many tubes. That's the good part. Something to look forward to. Trying out new tubes is a gas. But hopefully not too much gas, tube gas that is. Whatever that is.

 

[Learner]

[quote author="CJ"]You mean besides an EF804S? [/quote]

Yea, anything. Preferably CHEAP!!! :grin:

Man...... that EF804$ is one of those vintage priced Telefunken V72 rare ebay big mon-nay tube. :? I won't be able to get any where near one of those.......

 

[CJ]

Oh, now I get it. You want to know what tubes are killer for audio, but dirt cheap because nobody knows about them.

Well, they are out there. But thanks to Eric Barbour and his Dumpster articles, slowly but surely the cat is getting let out of the bag. Take for instance, the "useless" 12SX7 that use to get used for target practice. Now they are 25 bucks at Antique because they sound better than 6SN7's.

Or there was the WeCo 417A that you might have noticed a while back. Use to be able to get those for a buck sixty. Now they are close to forty smackers.

There are still some deals out there. Like the 6AV5. Killer tube. Good as a 6L6 in some cases. Used in old Bogen's. $4.35 at Antique. Don't tell anybody. (wait, I just did, me lardass!)

Others you might find in the basement that are cool are the 5687, 6FQ7, 6900, 7044, 7119,...

The 5687/2C51 type, which everyone curses because people rebrand them as 6386's, can be used for audio. Pretty cheap still. Just hookup whatever you got and give it a shot. You might be the next tube hero, if you don't electrocut yourself in the process. Observe pinout data.

 

[gyraf]

For dirt cheap, good audio tubes, you may want to look into the PF86 audio pentodes. It's a (300mA) series-heated version of the EF86, and even Tele ones are still dirt cheap. They seem to react very well to slight underheating - so they're a very good choice for tube mics imo.

Othe tubes from the "P" european series-heated types are also good candidates - like the PCC88's extensively used in EAR stuff..

Jakob E.

 

[cantgetnosleep]

Sometimes you can learn a lot about something by studying the opposite condition as well. By this I mean, you might also gather up the worst sounding preamps/tubes and see what makes them so bad. You could then extrapolate backwards to some qualities in the best preamps. This should at least be cheaper than studying a bunch of excellent preamps, although maybe not as much fun.

Just a though - Andrew

 

[Learner]

[quote author="CJ"]Oh, now I get it. You want to know what tubes are killer for audio, but dirt cheap because nobody knows about them.[/quote]

:green: :green: :green: :thumb:

Well, they are out there. But thanks to Eric Barbour and his Dumpster articles, slowly but surely the cat is getting let out of the bag. Take for instance, the "useless" 12SX7 that use to get used for target practice. Now they are 25 bucks at Antique because they sound better than 6SN7's.

Right, even with all those tips I think there are still at least a few out there. Since people rarely venture out of the 12a..7 tube land.... Speaking of 6SN7 and the 6SL7 stuff, ther are so linear I don't find them sounding any different comparing to standard generic ICs such as the 7*1 :shock: :shock: :razz:

BTW, wanna PM me the rest of the tubes thats still in the bag??? :green:

You might be the next tube hero, if you don't electrocut yourself in the process. Observe pinout data.

ha, I donno about being a hero since they are usually the first one to die when sh*t hits the fan :shock:

 

[Learner]

[quote author="gyraf"]For dirt cheap, good audio tubes, you may want to look into the PF86 audio pentodes. It's a (300mA) series-heated version of the EF86, and even Tele ones are still dirt cheap. They seem to react very well to slight underheating - so they're a very good choice for tube mics imo.

Othe tubes from the "P" european series-heated types are also good candidates - like the PCC88's extensively used in EAR stuff..

Jakob E. [/quote]

Cool, thanks Jacob!! :thumb:

Will check out the P series tube, however I donno there is such thing as Telefunken tubes and CHEAP :shock:

 

[gyraf]

I donno there is such thing as Telefunken tubes and CHEAP

There is. Last time, I paid something like 2.15?/ea for Tele PF86's from some german distributor. Schuricht? Pollin? Reichelt? something like that - but I cleared out their stock (they only had 10-15 pcs anyway). But look around - the series-heated tubes were made in very-very large amounts for television sets, and later nobody wanted them because they were non-standard heater voltage..

(and once I managed to buy six Tele VF-14K's for 4?/ea, but that's an entirely different story :grin: )

Jakob E.

 

[Learner]

[quote author="cantgetnosleep"]Sometimes you can learn a lot about something by studying the opposite condition as well. By this I mean, you might also gather up the worst sounding preamps/tubes and see what makes them so bad. You could then extrapolate backwards to some qualities in the best preamps. This should at least be cheaper than studying a bunch of excellent preamps, although maybe not as much fun.

Just a though - Andrew[/quote]

Hey that's not a bad idea!!! Plus it is more achievable with my kinda budget :green:

I think may be I should change the name of the thread to ultimate worse sounding tube you have ever encountered???

The reason I want to study those excellent pres is because it has a rep of being sounding "good" and I would like to know what causes it and why that is.

Actually what I am trying to look for are tubes that leaves unforgettable or recognisable impression on people after listening experience, may it be "good" or "bad" since they are just personal opinions and I think the V72 is a good example of this situation.

Anyone got any more? ie. tubes with the most non linear response.


BTW, cantgetnosleep. Tried ordering some prozak online? Smoking some ganja might be a more organic way to put on weight, I mean sleep.

 

[adamasd]

Try a 6SL7 in grid leak bias, or bias into a very unlinear range. Sure they can be very linear, but they do not have to be at all. They are one of my favorite tubes, same with the 6SN7, really can sound quite fantastic. Lately I have been playing with the 6S4a which costs nothing. I am likeing it alot, it is a nice sounding tube, makes a nice little 2 watt amp also. The 6J4 is the next tube on my list, I like its specs, but that means nothing.

adam

 

[cantgetnosleep]

Learner,

Yeah, I like your idea. You want to study the 'good' tubes and try and isolate the mechanisms or effects which cause the to sound good. Right? Cool idea. I'm pretty new and ignorant about audio electronics, but I have a good background in science (mostly biochemistry, genetics and some computer science). Maybe I'm telling you something you already know here, but I'll say it anyway in case it'll help.

If you want to go about this rigorously, you should try and verify that there is actually something there that you want to study before you try and isolate the property (this can save you a lot of fruitless work). It might be a good idea to do some blind tests with different tubes to isolate a few that consistently sound better to a number of different people. This will help insure that you are actually studying something concrete, and not just nebulous personal preference, which will be very hard to isolate consistently with a scope.

If you find a set of tubes that consistently are picked by the study group as sounding 'good' then you can look at what common qualities they posses and make a hypothesis as to what qualities make them sound good. Idealy, you would then try and find some previously untested tubes and make predictions on their sound quality to test your hypothesis. Or perhaps you could devise a circuit to emphasize the positive qualities and diminish the negative qualities. Regardless, if your hypothesis is verified by experimentation then you are on the right track. Of course, the verification study should be double blind to insure proper objectivity. The brain is pretty good at percieving what you expect to percieve, and you have to be very vigilant against that in a scientific analysis.

Hmmm...sorry if this is overly didactic. I don't know much about tubes (yet), but I know a little about scientific analysis, so I figured I'd share what I can :grin:

It would be interesting to see a study such as this done objectively, there is definitely a lot of opinion and ad copy on the subject.

r/ the prozak and the ganja. yeah, that'd be nice, but it's not time or the place for that in my life right now. Actually, I'm working a lot of hours these days, so I sleep pretty well. Cangetnosleep is left over from a much more nihilistic phase of my life and was pretty apt at the time. I think Mark Twain said, "Two things in life I hate are going to bed at night and waking up in the morning." That's kinda how I am usually.

 

[Learner]

[quote author="cantgetnosleep"]Learner,
If you want to go about this rigorously, you should try and verify that there is actually something there that you want to study before you try and isolate the property (this can save you a lot of fruitless work). [/quote]

Yes, that's what I am attempting to do. I have experienced the difference of audible perception in tube vs solid state amps. Which is the reason that got me curious in the first place to search of factors that contribute to this audible effect in tube amplifers, that's how I found myself to be involved with tube audio.

Appearantly I am not the only one that has experienced this difference, words such as warmth as such has been associated with the description of tube audio. However, I do not really understand the assciation of warmth with tube audio because I don't think I have quite experienced it. OTOH, I do have experienced different types of effect generated by different tubes which to me feels like some sort of manipulation of the sound image.

Of course, some tubes I can not seem to perceive ANY effect whatsoever. For those that seems to have an effect the effect varies from tube to tube, some seems to enhance the sound image and causes a pleasant effect others does the opposite.

Personaly, I believe the effect also varies with the music that's being played using the amp. That is, I believe that some tube/amp are "good" for playing music(ie.CDs) and some tube/amp are not "good" for listening but seem to work very "well" for recording CERTAIN instruments because of the way it manipulates the sound image that places the instrument in certain spot when perceived through the speaker.

I have yet to implement my personal opinion stated above thoroughly in practical experiments to be certain of my current suspicion, however I do plan to do so except that I would need to build a lot of various prototypes of amp based on different tubes before I can carry out the listening test. That, is what makes it very time consuming since I would not only need to bias the same tube with different setting eg. FB and no FB plus mix and match different tubes times the possibilities of circuit layout eg. serial with parallel tube output or serial with parallel output with another overall parallel stage etc.... makes it difficult to be able to cover a large area of work in a short period of time....

Anyway, the purpose of this thread was to see if anyone else has experienced any kind of obvious effect with tube amps so it would give me a clue on what type of tubes to try and see if the effect are common even with different types of tubes. Meanwhile, it allows me to explore or discover new audible effects indicating that each effect is unique to each tube.

I would love to be able to listen to some sound clips recorded from classic tube pieces such as Fairchild or Pultec just to experience and have an idea of what this perception is like, also its a good indication of what people think of sounding good is.

 

[analag]

I would love to be able to listen to some sound clips recorded from classic tube pieces such as Fairchild or Pultec just to experience and have an idea of what this perception is like, also its a good indication of what people think of sounding good is.

That's subjective everybody hears differently....for example I love tubes without transformers, yet a lot of people like it with transformers. Still I'm brave enough to stick to my guns despite popular opinion. I believe in trying to extract new sounds from the glass....imagine if the old designers had the tools and the parts we now have. I think they would kick our *****...because they looked ahead and we are looking backwards.

Analag

 

[Learner]

I would love to be able to listen to some sound clips recorded from classic tube pieces such as Fairchild or Pultec just to experience and have an idea of what this perception is like, also its a good indication of what people think of sounding good is.

[quote author="analag"]That's subjective everybody hears differently....[/quote]

Yes, it is subjective HOWEVER these clssics are the most commonly recognized by users as great sounding unit. Do you know or have you heard of anyone that are users of these unit saying that they sound like crap???

Which is the reason why I think it would be worth studying these units, such as looking at the frequency response of the unit and listen to clips recorded on it.

Then try to duplicate the frequency response on a 1/3 octave 31 band graphic EQ and listen to the same sound clip that has not being recorded through those units, do you get the same impression when you listening to both clips recorded and not recorded using the classics? If not, why not???

Could it be possible that the spectrum analyzer is not displying exactly what you are hearing??? :shock:

for example I love tubes without transformers, yet a lot of people like it with transformers. Still I'm brave enough to stick to my guns despite popular opinion.

mmm..... interesting approach? philosophy? :?

I do not have any specific believes on implementation based on a particular method, to me different ways of implementation are just alternatives that you have in order to achieve a certain goal and are tools available to get the results that you might want. Getting the result that I am looking for in this physical world is the only thing that counts for me, I do not see any advantages by imposing restrictions during the process of implementation not to mention it minimise the alternatives that might be available at your disposal.

The only approach that I have when it comes to implementation is trying to make things simple, effective, economical, durable and reliable.

I believe in trying to extract new sounds from the glass....imagine if the old designers had the tools and the parts we now have. I think they would kick our *****...because they looked ahead and we are looking backwards.
Analag

Heh, I think some of them are still around and are GLAD to be out of the tube era and couldn't get away far enough from this out of date obsolete technology as possible. That seems to be the impression I get, when ever/where ever I speaking to an EE oltimer from "back in da days".

I am not a fan of this glass technology due to all the obvious reasons that has driven EE technology to ICs, I am just trying to understand the artifect embeded in this glass technology which contributes to the audible outcome that people seems to find it "pleasant" including myself.

 

[bradzatitagain]

No unit in particular, but this circuit and its variants is worth investigating:

http://www7.taosnet.com/f10/mustage.html

Peter mentioned Alan Kimmet's mu-follower a couple of months ago, I've just been diggin into it. Line stage, phono stage (hi-fi,) mic pre. If you use tubes instead of MOSFET/tube you sit a pentode on top of a triode. On a different forum PRR suggested trying vertical deflection tv tubes. The EF822 was super cheap until dealers started selling them as replacements for EF86's.

The gain is equal to the transconductance of the triode, maybe a little more free gain with the in/out xt's. Try different tubes in combination with different in/out iron. Could be intersting to put a dual triode gain stage in front of it, like a variation on the G9. But as it is it's intriguing, especially if you can find a dual pentode triode that will work. signifcant real estate gains in your rack, one tube per channel. Might even be able to get 8 in 2U if you mount the tubes horizontally and use a low profile power transformer, maybe even 1U w/ a torroid. That's be very cool.

 

[analag]

I am not a fan of this glass technology

I am, it is my first love in electronics. Because of that I have been able to squeeze glorius performances from them...even the generous Analag keeps back a few things. Did I just say that?

Analag

 

[Peter Simonsen]

[quote author="Learner"]Hi guys,
Just out of curiosity, I was wondering if anyone could nominate your all time favourite tube pre(mic or line) that you have used?
[/quote]

uhh I know this one is nearly to much, but a man gotta be honest.. My all time favourite tube preamp is my own :green:

Kind regards

Peter

 

[Learner]

[quote author="analag"]
I am, it is my first love in electronics. Because of that I have been able to squeeze glorius performances from them...[/quote]

That's nice to know.

Perhaps you might be able to help me out directing me to some tubes of your preference solely due to the way it sounds?

even the generous Analag keeps back a few things. Did I just say that?

Analag

heh, there is nothing wrong with that!
I would suspect that you are probably very familiar in building HV PSU by now?
Got any advise for newbies like me settling in with a discrete HV PSU?? Better yet, a fully working tested circuit would be real nice!
:green:

 

[Learner]

[quote author="Peter Simonsen"][quote author="Learner"]Hi guys,
Just out of curiosity, I was wondering if anyone could nominate your all time favourite tube pre(mic or line) that you have used?
[/quote]

uhh I know this one is nearly to much, but a man gotta be honest.. My all time favourite tube preamp is my own :green:

Kind regards

Peter[/quote]

What kind of tube did you use? Have you ever compared it to some well known commercial unit? How do they vary in terms of the sound?

Sorry to venture into the land of tube sound description again but that seems to be the only way of feedback online, since there just don't seem to be any sound clips available... :roll: