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Tube gear section.

Do you want a tube gear section ?


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fpitas

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Case in point: you can easily simulate tube amps in a fairly convincing way using various DSP effects (the number of decent tube distortion VST plugins is massive, even for free)... but hardly anyone uses these.

If you really just wanted tube sound you can get it very cheap or free.

Yet, we have a disturbingly robust market for actual tube amps. I think the appeal is the tubes themselves. If it were anything else, cheaper solutions would have completely taken over ages ago.
I know guitarists who use DSP to simulate the sound of old Hiwatts, Marshalls etc. and use a small, lightweight SS amp to save their backs lugging tube amps around.
 
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fpitas

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"Competently designed" IF the goal was inaudible distortion. That's not necessarily, it seems, what some tube amp manufacturers are going for ("if it sounds the same as SS, why bother?")

So "competence" should be judged based on the goal of the designer. (For instance, Nelson Pass is, I believe, known as a competent designer of SS amps and has produced models with inaudible distortion. But he's also known for deliberately designing for slight distortion in some models).
I'd like to think you're right. Thing is, we've seen so much badly designed high-end stuff come through here I'm a bit cynical.
 

Doodski

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Since tubes lend themselves to DYI more than S.S. stuff does due to their simple circuits and their tendency to sorta work even if not done exactly right, a DYI-tube area might work. power amps, preamps, crossovers, da woiks.
With a disclaimer about not being responsible for stuff if bad stuff happens.
 

MaxBuck

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"Objectively" inferior implies agreement on the goal of the equipment.
My post commented upon fidelity. Think about what kind of componentry produces maximum fidelity to the source material. If that's not your goal, I wonder why you're here.
 

MattHooper

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Case in point: you can easily simulate tube amps in a fairly convincing way using various DSP effects (the number of decent tube distortion VST plugins is massive, even for free)... but hardly anyone uses these.

That's because they are made for audio professionals typically using a DAW (like myself). I'm not aware of any such plug-ins for consumer equipment.
Also, having played with some of the tube plug-ins in the past, they were more suited to modelling the heavier distortion one finds in, say, guitar tube amps.
I didn't find they perfectly mimicked what I perceive from my tube amps in my stereo system.

Yet, we have a disturbingly robust market for actual tube amps.

Why should this disturb anyone? There are niches. People have fun with niches. I'm not disturbed by the niche market for bikes-with-fat-tires or whatever.


I think the appeal is the tubes themselves. If it were anything else, cheaper solutions would have completely taken over ages ago.

Admittedly, if there were a consumer tube modeller that was just software...yeah it would take some of the fun and appeal out of it for many.
I'd include myself. I like the physical aspect of tube amps too.
 

egellings

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With a disclaimer about not being responsible for stuff if bad stuff happens.
That would be true for any project that does not end up working well. With tubes, of course, there are the dangerous high voltages not present in S. S. stuff, so chances of serious personal injury are there with tubes.
 

DMill

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"Objectively" inferior implies agreement on the goal of the equipment. Tube fans aren't (the clear-headed ones, anyway) interested in true fidelity, they're interested in euphonic distortion or maybe just cool-looking equipment.

For tube amps to be objectively inferior they would have to be judged on the same basis as solid state amps, but IMO their users don't really judge them that way. Or at least, I hope they don't. They're definitely worse in general at quantitative measures of fidelity, but if their users cared about that above all, well, they probably would not be using tube amps.
Yup. I have another rig now too. They’re just fun if you want to play. Mine sounds better than you might think compared to a Yamaha AS1100. Gotta get loud and then maybe I hear the tubes getting a little muddy. Haven’t tried Class D yet, but think I’ll give Buckeye a shot in the near future.
 

MattHooper

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I'd like to think you're right. Thing is, we've seen so much badly designed high-end stuff come through here I'm a bit cynical.

Ok, fair enough.

I've also said before that I think there is often a sort of "hide the goal" that can go on with the advertising for tube amps. So if we take for sake of argument the tube amps with higher distortion, you rarely if ever see the manufacturer touting the "distortion my amp gives you." Rather they couch it in more euphemistic or attractive ways "more pure, Gets You Closer To The Music." I think many audiophiles keep chasing an ever more "transparent" source or amplification and so most stuff is sold on those grounds (even if the manufacturer knows full well he's producing a design that departs from neutral or produces distortion).
 

Robin L

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Having a "tube section" would serve to validate, to some extent, objectively inferior gear. As my understanding of the goal of this site is to identify and celebrate excellence in high fidelity, which frankly is not something that tube gear is capable of, it just seems out of place.

Then again, it's @amirm's site; he should do as he likes.
Except that there might be outliers that successfully leap over SINAD barriers. Only one way to find out. Of course, that means folks sending in fragile, easily damaged stuff. But go for it, the results would be interesting. And there might be room for more folks doing measurement/reviews here. I think that would be valuable.
 

kemmler3D

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That's because they are made for audio professionals typically using a DAW (like myself). I'm not aware of any such plug-ins for consumer equipment.
Also, having played with some of the tube plug-ins in the past, they were more suited to modelling the heavier distortion one finds in, say, guitar tube amps.
I didn't find they perfectly mimicked what I perceive from my tube amps in my stereo system.



Why should this disturb anyone? There are niches. People have fun with niches. I'm not disturbed by the niche market for bikes-with-fat-tires or whatever.




Admittedly, if there were a consumer tube modeller that was just software...yeah it would take some of the fun and appeal out of it for many.
I'd include myself. I like the physical aspect of tube amps too.

IIRC you can run VSTs in Voicemeeter or EQAPO, close enough to consumer for many.

"Disturbing" only in the sense that it would be inexplicable if you assumed everyone was after true fidelity and nothing else. Just dramatic language.

You are right that most VSTs go for pretty heavy distortion, but if you haven't checked out the Variety of Sound plugs, they're well worth a look for subtle harmonic distortion. The guy is very diligent about modeling nonlinear effects and carefully studies the harmonic output of real gear. Most of his stuff simulates solid state, but there's some tape and less-specific types of distortion in there. Generally the effects are (IMO) euphonic but pretty subtle, like the intensity of distortion you'd get with an actual IRL amp, tape machine or other bit of analog gear.
 

MattHooper

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Having a "tube section" would serve to validate, to some extent, objectively inferior gear. As my understanding of the goal of this site is to identify and celebrate excellence in high fidelity, which frankly is not something that tube gear is capable of, it just seems out of place.

As some have mentioned, tube gear can be audibly transparent to the source.

But, that aside, while I don't see anything wrong of course with a forum being devoted to only "excellence in high fidelity gear" (and hence the most transparent and accurate), my take is that the forum isn't quite that restrictive. I see it as a place to come to gain accurate knowledge about how audio gear does (or doesn't) work. It doesn't enforce that anyone choose a particular type of gear. If you want technically inferior gear, you can choose that, but around here you'll understand what you are choosing.

I think this understanding matches the tenor of this place, and explains why there's even a part of the forum devoted to turntables. :)

Then again, it's @amirm's site; he should do as he likes.

Agreed.
 

GXAlan

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Yes, BUT only if science is the theme as opposed to just subjective comments.

The fact that tubes exist in music reproduction (not just music generation) suggests that euphonic colorations exist. However, science has failed to demonstrate even and odd harmonics, etc.

There is also data that suggests a good tube amp has lower distortion at the very lower power of 50 milliwatt EVEN compared against the AHB2. A forum dedicated to looking at tubes in the 10 to 50 mW range could be interesting.

The advantage of separating tubes is that those who do not want anything to do with tubes can be spared from reading about it.
 

mhardy6647

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There is also data that suggests a good tube amp has lower distortion at the very lower power of 50 milliwatt EVEN compared against the AHB2. A forum dedicated to looking at tubes in the 10 to 50 mW range could be interesting.
Those of us who use loudspeakers exhibiting > 100 dB SPL /watt (@ 1 meter) sensitivity... already kinda sorta sussed this out. :cool:
 
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GXAlan

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Those of us who use loudspeakers exhibiting > 100 dB SPL /watt (@ 1 meter) sensitivity... already kinda sorta sussed this out. :cool:

Right. And you really don’t need 100 dB SPL/2.83V speakers. Even mid 90’s in efficient is already easy for listening at levels that don’t destroy your hearing.

But just as there is a HUGE spread in performance among solid state amps, I am sure there is an equally HUGE spread in performance across tube amps. They’re not going to be all the same.

There is also the question of tube amps that leverage things like solid state rectifiers. I bet those are great at measurements as opposed to hybrid amplifiers with tube buffers and solid state amplification which may end up with the worst of both worlds.

Last, there is debate on tube rolling. Is this the same as sighted bias/cables? Or are there differences at different bias or volume?

Everyone insists there are tube simulators for sound, but this is only for tubes in music creation and overdriving into distortion. Now that the AHB2 vs Dynaco data is out at 50 mW, it would be interesting to see if at 25 mW it is even more different.
 

MattHooper

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Last, there is debate on tube rolling. Is this the same as sighted bias/cables? Or are there differences at different bias or volume?

I'm bummed because I had a chance to actually blind test tube rolling in my amps, but it didn't happen. For a while I had two pairs of the same tube amps.

I own Conrad Johnson Premier 12 monoblocks, which are quite old, and I bought a more updated pristine-condition pair at a price below what I knew I could sell them for. A "bonus" was that the pair had gone to Conrad Johnson where then went over it and also did the Teflon Cap "upgrade" - one of their expensive upgrades (yes, I know how that will be greeted here). So I originally planned on keeping those newer, better condition amps and selling mine. I wasn't necessarily expecting a sonic difference - it being more of a chance to have a newer, better condition pair of Premier 12s.

As I mentioned in some other thread, I was surprised that I seemed to hear a very "obvious" difference - the bass seemed tighter and deeper, the highs a bit brighter, and everything sounded "bigger" than what I'd been used to. The guy who sold it to me sent it with KT120 tubes (and different rectifier tubes) where I'd always had 6550s in my amps. So I swapped those KT102s to my old pair of CJs just to check and much of what I "heard" transferred to my old amps.
That was so fun I tried all sorts of tube rolling, and often perceived differences. Even more surprising, the new CJs (with the Teflon caps) consistently seemed to have tighter, more controlled bass even when using the exact same tube compliment from my old amps.

Naturally I wondered how much could be due to human bias effects and would have loved to do a blind shoot out between my old and new CJs, both for tube rolling and to see if I could actually identify the "updated" model. Perfect situation! I even asked about this in ASR because I was aware it's a bad idea to swap speaker cables between live tube amps. I got some suggestions as to how to protect the amps/speakers but in the end chickened out. My finances demanded I had to sell the new amps pronto! And there was no way I was going to even chance something happening to those amps (or my speakers) at that point. Someone with electronics knowledge/experience I'm sure would have had no problem going ahead, but I just wasn't confident enough. Sold them shortly after.

I still wish I could have done that blind shoot-out. (I failed my ASR brothers....)
 

MaxBuck

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Except that there might be outliers that successfully leap over SINAD barriers. Only one way to find out. Of course, that means folks sending in fragile, easily damaged stuff. But go for it, the results would be interesting. And there might be room for more folks doing measurement/reviews here. I think that would be valuable.
Sure. But I don't see that not having a special tube subforum has prevented people from sending in tube components.
 

GXAlan

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A "bonus" was that the pair had gone to Conrad Johnson where then went over it and also did the Teflon Cap "upgrade" - one of their expensive upgrades (yes, I know how that will be greeted here).

Capacitors can affect SINAD, proven here:

The "faulty" capacitor in the original x6700H puts it ahead of non-broken JBL SDR-35, Arcam AV10...

The guy who sold it to me sent it with KT120 tubes (and different rectifier tubes) where I'd always had 6550s in my amps.
...
My finances demanded I had to sell the new amps pronto! And there was no way I was going to even chance something happening to those amps (or my speakers) at that point. Someone with electronics knowledge/experience I'm sure would have had no problem going ahead, but I just wasn't confident enough. Sold them shortly after.

Do you have a tube tester? How do the CJ's control bias? By the measurements, there isn't a lot of difference between tubes at similar bias (but at different bias, there can be big differences.) I also wonder how different tubes change over time (within a listening session). Visually, they all don't glow equally! :)
 

DMill

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I still wish I could have done that blind shoot-out. (I failed my ASR brothers....)
Nah. You didn’t fail I think. It’s so hard to do a true A/B test, especially with rolling tubes. I did some half ass experiment years ago with a couple of friends. By the time we got the new tubes in the amp. Biased them and reset SPL it was 20 minutes later. Might has well been 20 months later at that point. I personally didn’t hear differences. A couple of us thought we heard something different. But I don’t think anyone could say it was better with a $30 Tung Sol 6sn7 vs. $200 NOS Tube. Heard nothing different rolling rectifier tubes. My amp can take different power tubes so might have been a difference there but would want a cleaner test than we did to confirm
 

Chrispy

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Generally no as I doubt everyone who likes/uses tubes would use it exclusively, where it would have some value in opposition to more commonly used and current gear than such a weird subset. :)
 

MattHooper

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Capacitors can affect SINAD, proven here:

The "faulty" capacitor in the original x6700H puts it ahead of non-broken JBL SDR-35, Arcam AV10...

Interesting. Thanks.
Do you have a tube tester?

No.

How do the CJ's control bias?

A bias pot for each output tube. So manually, each time I change power tubes.

By the measurements, there isn't a lot of difference between tubes at similar bias (but at different bias, there can be big differences.) I also wonder how different tubes change over time (within a listening session). Visually, they all don't glow equally! :)

Yeah...I dunno. As I understand it, while the KT120 tubes can under the right circumstances produce more power, you don't just get more power dropping them in place of 6550s. The amp has to be designed specifically to get that extra power out of the KT120. (And even then, it's not a huge gain).
So even if I am hearing the difference I seem to hear, that wouldn't explain it. I had no experience at all with the KT120 tubes, never tube rolled in my CJ Premier 12s before, and wasn't expecting those tubes to come with the amp. So the sonic "difference" I heard came as a surprise. More intriguing is that, after I heard this difference I started to research the tube and came upon review after review from other tube amp owners trying the KT120 in place of other power tubes (like 6550s/KT88s). Over and over the differences they reported mirrored what stuck out to me: deeper, weightier, tighter bass and more extended sounding highs.

I can't say I know it makes sense - and...see my tag line...but it was interesting to me to see such relative uniformity on that tube.
 
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