Vintage Tube Amp Restoration Walk Through

[muel]

 

There's no point in tube gear if the source is digital files and digital streams.

 

expand on this thought please. 

 

No need to expand... I disagree. 

[Thaddeus Smith]

Digital. 

[Thaddeus Smith]

 

There's no point in tube gear if the source is digital files and digital streams.

 

This was a tiny bit too short for general audience. Let me correct it to say this. Setting personal whimsey aside, there is no good sonic benefit to use tube gear if the source is digital.

I hope it goes without saying, that it's just my opinion after many years designing tube amps.

 

 

Again, I want to know why you feel that way. My limited understanding is that except for some very recent offerings from NAD, all amps are analog - so why should the source material play into the decision?

[CECAA850]

If someone prefers the sound of a tube amp over a SS amp, what difference would the source make?  Clearly there are those out there that profess a preference between the two types of amplification.  That's where I don't understand the comment about there's no sense in tube amps if the source is digital.

[Thaddeus Smith]

No, which is why I'm asking you to expand on the opinion. I'm having a hard time thinking of any instance where I have heard both analog and digital sources through the exact same chain of devices/speakers.. so it's an unfair comparison.

Edited May 6, 2015 by Thaddeus Smith

[CECAA850]

Sometimes I make Thad answer for me just by thinking about it.  It's a gift.

[CECAA850]

Good example.  At the gathering we used multiple sources (analog and digital) with tube and SS amps, at times with no pre.  There was definitely a difference in the sound the combinations created.  Better or worse was subjective but a difference none the less.

[Thaddeus Smith]

Good example.  At the gathering we used multiple sources (analog and digital) with tube and SS amps, at times with no pre.  There was definitely a difference in the sound the combinations created.  Better or worse was subjective but a difference none the less.

 

but at no time did we only change between the turntable or cd player.

[oldtimer]

Tubes are a way to color the sound. If you like that coloration then do it.  My ears were trained with live music.  That's about as analog as it gets.  Thad have you been to a concert where there were guitars and a digital synth and drums all played through the same stage system?  And vocals of course?  Then you have heard both played through the same chain.

[Thaddeus Smith]

First of all, the advantage to tubes is the physical characteristic of the transfer function versus BJTs. To GET that benefit, you need to place it where significant gain is needed, not at the tail end of a DAC as a silly buffer with no gain. Where in audio is tremendous gain needed? Analog records and tape, of course, where upwards of 40dB of gain must be achieved with maximum linearity. THAT is why tubes became the magical leader in amplification - because they do it better.

 

In a digital system, the output of a DAC needs not much gain if any. Why on earth use a tube? I tell you why. It's good marketing. A tube being used as a cathode follower gives you all the coloration and none of the benefit. Why bother?

 

and that makes sense. thanks for the expanded explanation. 

[Thaddeus Smith]

Tubes are a way to color the sound. If you like that coloration then do it.  My ears were trained with live music.  That's about as analog as it gets.  Thad have you been to a concert where there were guitars and a digital synth and drums all played through the same stage system?  And vocals of course?  Then you have heard both played through the same chain.

 

just last week. electric guitar, acoustic guitar, electric piano, and drums. it sounded horrible because the engineer running the board thought "LOUD EVERYTHING IS THE BEST" .. it wasn't a big venue and the crowd was pretty quiet during each song. the volume levels were truly unnecessary and we ended up leaving early, it was just that bad.

[Thaddeus Smith]

 

Good example.  At the gathering we used multiple sources (analog and digital) with tube and SS amps, at times with no pre.  There was definitely a difference in the sound the combinations created.  Better or worse was subjective but a difference none the less.

 

Well, sure, a difference would be noted.

 

You know what film buffs say about 70mm film? "Man, the color is glorious." Guess what DOESN'T work? Converting the glorious 70MM film to digital, and playing it through a digital projector. "Man, that's lousy."

 

There's more.

A simple tube circuit is cheap. A good one is expensive and a great one is a lot of money. Everyone is running around buying $200 tube things to hang on their digital stack. Well, I've got bad news. That cheap tube thing is worse than a cheap SS thing. It's only at the VERY TIPPY TOP of stretching tube design that you achieve the benefit and that doesn't cost $200!

 

 

So how does this opinion stand against your comments in this thread, regarding this amp, which I now possess and use to amplify my DAC output?

 

https://community.klipsch.com/index.php?/topic/149147-fresh-off-the-bench/

[Thaddeus Smith]

and by the way, I like the sound with that tube amp being used vs. the solid state it replaced. so I'm just trying to reconcile my experiences with your statements (my ears perk up when you talk about technical things).

[muel]

I grew up with vinyl but as a kid I most often listened to recordings of records made to a Nakamichi tape deck. 

Anyway, I think the flaw in thinking that tubes are a waste with a digital source has to do with the fact (my opinion anyway) that many digital sources do a good job of screwing up the sound before it ever gets to the tubes.

 

It is funny to me how people will spend thousands of dollars on a vinyl rig and tireless work to get it set up for the very best sound only to spend a few hundred bucks on a DAC and then complain that digital sucks and vinyl is so much better.  Not that every dollar spent will necessarily equate to better sound but I'm pretty sure you can hear a trend there...

 

Spend as much on a well made DAC as you did your vinyl rig and listen.   

[Thaddeus Smith]

For many years I have mistakenly been recommending tube rigs to people, who very definitely should be using SS or all digital gear. I did this under the misguided idea that once anyone drank from the magic waters, they would be spoiled for any other drink. The superiority of a vinyl/tube rig seemed so entirely obvious to me that I did not consider carefully, that in fact, I did not know these people in a personal enough sense to have heard what the devil they are listening to and what they enjoy as sound. And, what the heck, if they want what you are selling, be sure to close the sale.

 

Call me a slow learner if you like, but it seemed a good assumption until the last few years. This is when I discovered the ear training. I would hear people talking about their system and they weren't describing any of the traits I would expect from tube gear, and in fact often describing negative traits vis a vis their SS gear. I might be slow, but I am also very observant, and I began to pay close attention to all this. The kicker was this idea of adding these "show tubes" that you see to every little device made nowadays. I knew that had to be pure crap in a bottle, because I have designed enough to know what it takes to sound good. I looked to my photography experience for a parallel, and there it was - film v. digital again - and guess what? - the same classification distribution fell out. If you grew up shooting big film, like me, you didn't like the look of even high end digital. And, the beginners for whom a digital was their first camera, were in love with that look. Well, for me, it took FujiFilm to come up with the Xtrans sensor, and some might powerful software, to turn digital images into something that brought back the analog feel.

 

We are not recorders. We do not take in all the data. We take in tiny amounts of sensory data and form whole images and sounds from it. The question is - which tiny bits? And that's what I think sensory training does. Gets you accustomed to specific sets of tiny data.

 

EDIT:

One more problem. I have now concluded that no matter what people say in written form about the sound of their system, it doesn't translate into anything meaning for me to judge. The pro writers who do reviews can hit me around 30% of the time if I have been reading them awhile. But just basic internet chatter may as well be smoke signals.

 

thank you for this.

[muel]

Interesting and some good points.  

 I agree it is a matter of taste in the end and it is amazing how bad some setups can sound (to me) and yet the owner loves it.  I'm still not satisfied with the sound of my OWN setup though.   My room makes it tough but I'm not moving anytime soon.  

 

I never heard tubes (not counting Grandma's tube radio) until about 6 years ago.  It was a jaw dropping experience for me.  

[CECAA850]

EDIT: One more problem. I have now concluded that no matter what people say in written form about the sound of their system, it doesn't translate into anything meaning for me to judge. The pro writers who do reviews can hit me around 30% of the time if I have been reading them awhile. But just basic internet chatter may as well be smoke signals.

 

I'm the worlds worst at putting into words what I hear.  I know what I hear.  I can hear subtle differences in components and sources.  I know what I like, I just have a heck of a time putting it into phrases that everyone else understands what is going on in my head.

[mikebse2a3]

Yes, I still feel tone controls are a useful feature, especially if they are by-passable when not needed. Having designed mixing consoles used in many recording studios, I also agree with statements made by Cello that the tonal balance of recordings is "manipulated" by the recording engineer based on both their “taste” and on their monitoring environment. Every mixing board I designed had tone controls (with at least 3 bands) on each input, and often included graphic equalizers on the output channels, and they did get used. The best engineers usually did a good job of trying to use equalization to only correct for recording defects. Some engineers went to great lengths to listed to several different monitors to be sure they were not over correcting based on one particular speaker/amp combination. But not all recording engineers are equal when it comes to their ability and time allowed to correctly compensate. Plus there are things like room acoustics, speaker performance, and personal tastes that can sometimes benefit from tone controls. So I would have to say that if done correctly, they can be quite helpful in recreating the playback tonal quality originally intended by the artist and recording engineer.

Thanks for the insights on this subject based on your experiences Ken...!

"So I would have to say that if done correctly, they can be quite helpful in recreating the playback tonal quality originally intended by the artist and recording engineer."

Once I really began to give a lot of thought to the whole recording/reproduction chain and the uncontrollable variables I realized it is a fallacy that many of us have or had locked ourselves into which is to believe and treat all/majority? recordings as an untouchable reference source because we falsely believe that we were hearing exactly what the artist and recording engineer wanted us to experience. Well designed and by-passable Tone Control Systems are the only option and best Tool we have to repair the damage and inaccuracies of the present day recording/reproduction chains we all live with and in many cases as you stated to actually approach what the really good artist and recording engineers wanted us to experience..!!!

miketn

Edited May 7, 2015 by mikebse2a3

[mikebse2a3]

Thanks! We certainly believe in rigorous testing, as well as critical listening

 

 

Agreed..... we must respect/acknowledge the abilities and limitations of both to help us achieve advances in the reproduction of music IMHO...!!!!

 

Very Impressive testing program....!!!

 

 

miketn

[oldtimer]

Interesting and some good points.  

 I agree it is a matter of taste in the end and it is amazing how bad some setups can sound (to me) and yet the owner loves it.  I'm still not satisfied with the sound of my OWN setup though.   My room makes it tough but I'm not moving anytime soon.  

 

I never heard tubes (not counting Grandma's tube radio) until about 6 years ago.  It was a jaw dropping experience for me.  

I have heard plenty of tubes and none of them dropped my jaw.  I would ask the same question mdeneen asked:  What did you train your ears with?

 

Edit: Reread your prior post so I get the idea. 

Edited May 6, 2015 by oldtimer