Exploring The Various Tube Types

[My name is mud]

This post is why I don't understand why the various tube types are even changeable parameters. If changing them doesn't change the sound, why include them at all?

and that’s not the only thing in the advance parameter that I tweak and then do a « ???? » face . Then some guys here said « wow I change to 0,2 this parameter and wow ». So maybe that’s me ? Maybe I don’t feel the difference with high gain sounds.
cliff will say : « so don’t touch it ».
and that’s exactly what I do . I try, No change ? Never again .

but that’s sad in a way considering that 2 JJ preamp tubes In real life cost 50 and here you don’t listen « nothing »

 

[Rex]

and that’s not the only thing in the advance parameter that I tweak and then do a « ???? » face . Then some guys here said « wow I change to 0,2 this parameter and wow ». So maybe that’s me ? Maybe I don’t feel the difference with high gain sounds.
cliff will say : « so don’t touch it ».
and that’s exactly what I do . I try, No change ? Never again .

Never say "never." Those parameters where you change them and hear no change — revisit them in a year or two. Some of them may surprise you. And some of them... may not.

 

[Budda]

Why would they holler when Cliff has made it clear it doesn't make any difference?

Because people complain, loudly, when something isnt there that they expect to be there. See: forums.

I think the power amp controls + tube type is where more educated users can really pull sounds out of a specific tube type. I am not that user, but do odd swap anyway.

 

[Rex]

Rex:
“A big part of the tube's interaction with the circuit has to do with the tube's impedance, which varies from tube to tube. Play around with XFMR MATCH to simulate that interaction.”

I’m curious if adjusting those parameters would simulate adding tubes to say the JC120 amp sim which has no tubes. Or would adding tubes abd increasing sag be necessary.

I don't think it works that way. Tube and transistors react differently to changes in impedance.

It would make an interesting experiment, though.

 

[Joe Bfstplk]

Is is true that 5881 and 6l6gc are the same?

Depends on which 5881 is being modeled.

A real, vintage USA 5881 is the industrial version of the old 6L6WGB tube, which is an uprated, ruggedized 6L6GB, as denoted by the W in there (think Elmer Fudd: 'Wuggedized').

A 6L6GC is rated to handle/produce more power than the 5881.

The tone is similar but nit identical. Based on personal experience with Sylvania 5881s in years past, the mids and top tend to sound a little more forward than the GE 6L6GC. Not sure how the currently available overseas 5881/6L6GC types compare, but the old suffix lettering system, which at one time had fairly strict meaning, is now played fast and loose for marketing purposes a lot of the time....

Sovtek 5881 tubes are not true 5881 tubes, but a relabeled Russian military tube. They sound best to me at a higher plate load than Fender and Marshall used. 6k6 plate-to-plate us a nice load for them. They are really consistently manufactured, probably due to their military origin, and/or the selection process surrounding that origin. Back when I was matching output tubes for Antiaue Electronics, I had to tighten up the matching specs quite a bit to leave 'singles' for those who wanted them.

 

[shemihazazel]

Because people complain, loudly, when something isnt there that they expect to be there. See: forums.

I think the power amp controls + tube type is where more educated users can really pull sounds out of a specific tube type. I am not that user, but do odd swap anyway.

I'm not either, but being held hostage by a cadre of screeching dullards is counterproductive for everyone.

 

[boyce89976]

Many of the power amp settings are normalized to the chosen model, so the actual values of those parameters wouldn’t change.

Ah, okay, that makes sense. Thanks!

 

[Stratoblaster]

I'd love to hear more about your experience as you play with different models! I mostly play Triptik Clean with a Tone of Kings out front and I've been loving the EF86-->6CA7 for that setup.

Ok cool...I get carried off in tangents at times as I like to explore one particular parameter, component, or stage in the AMP block and geek out just for hours getting them to fold, spindle, and mutilate to uncover their secrets...then I log in here and babble so thanks for reading lol.

Interesting preamp/power amp tube combo you have there, I've read a other few players here liking the EF86 for cleaner/mild-OD tones too. Trying out the various Preamp tubes is on the list as are deep dives into the Cygnus "Cathode Follower" stuff and the new "Speaker Compression".

Swapping tube types on my favorite amp sims...which are generally FAS amp blocks... I cannot hear a difference at all. Do y'all find that it presents mostly on NMV amps?

In general, I've found both MV/NMV amps show differences only when you start to push the power amp, and the more you push it the more the differences become apparent until they are completely maxed out. Moving a bit of air also helps here; with headphones the changes might get blurred.

If a MV amp with it's MV control set low-ish so the preamp tone is dominating you'll hear/feel subtle, if any, differences in swapping power tube types...again, depending on how much the PA is, or isn't, clipping/compressing. The Headroom meter is a fantastic tool to see what the PA is doing and how it responding.

Similarly, if a NMV amp has it's input level turned low so the PA is running clean, or only slightly compressing, you're hearing the preamp dominate the overall tone/feel and changes may not be as apparent.

An interesting thing to try is to take a Fender Deluxe Verb, or similar NMV amp, and tweak the Input Drive until you hear/feel the PA start to work and begin to 'chew notes'. Get it right on the edge where you can dig in/pull back to ride the 'crest of clipping' heh. Then, start to swap power tubes at that point. I found the differences in tubes type parameters (gain/transconductance curves, response, compression, hard/soft clipping, etc.) when swapping at this set-point was generally the most revealing of the various characteristics.

I did the same type of testing with some MV amps with more crunchy/distorted/higher gain tones...just set the MV in a similar way (right on the edge) after setting the Input Drive to taste.

Then, when you find a tube you like overall with the current setup, further playing dynamically with the right hand, and/or tweaking the preamp and power amp levels, start to show even more nuances for the many tube parameter differences.

I really love geeking out like this with Cygnus; it's by far the most fun I've had playing amp-doctor with any FAS platform by far

 

[Stratoblaster]

Cliff notes changing LF & HF resonance can simulate changing tubes.

Yes indeed, Cliff's notes on this subject are astute and a good read...while LF/HF effects likely have the largest overall influence/affect on tone, other tube parameters (transconductance, clipping threshold, harder/softer clipping, etc.) won't be able to to show their flavoring if only tweaking the LF/HF resonance I would think...???? But, LF/HF tweaks just might be enough to get you 95% where you want to be in this case. We are taking minutae and some pretty fine tuning here which may be more academic then generally practical....but fun!

 

[Stratoblaster]

6V6
My favorite for single coils, especially for single notes on the neck pickup, for clean-ish, mildly driven/OD bluesy tones.
Punchy, fat, creamy, chewy with a full body and snap which really sings nicely with sweet Fender amp.

Reading this today reminds me of someone evaluating fine wine...or scotch lol...

"The 6V6 has a full bloom, and possesses a rich body and harmonics that start bold and finish cleanly, with just the right amount of sharpness to the attack. Paired with a fine vintage Fender, or even a modern boutique amp, you'll find this tube is a cut-above the more typical offerings and compliments single coils and bluesy tones perfectly."

Let the cork-sniffing begin heh.

 

[yoitsmegabe]

I wish there was a "normalized/non normalized" option for the tube swaps. It really is subtle to hear the differences in the axe, but on my amp heads that allow 6l6 el34 swaps I hear the difference more pronounced. If I'm honest, I would probably mess with it and end up back in normalized because I'm used to the sounds I get with the axe as is.

 

[Fab8040]

Thank you to everybody.. To be honest i understand nothing in electronics.. My was just a curiosity because in the axe i use almost only the soldano slo which is set with 6l6gc in the power amp.. Listening to michael soldano also about the new version he s always talking about 5881.. I ve tried to swap the tubes and in fact there is a minimal difference.. Others parameters should be changed or all the same with this 2 tubes?

 

[komorebi_dayo]

one trick i was playing with just now is to use the hiwatt tonestack on a mostly clean amp. set up your eq how you like it, swap to the hi power tonestack, mid position, 700 Hz center freq. the compression and clip characteristics feel more distinct to me on each type, even on the interchangeable sets (6L6GC/5881/KT66, EL34/6CA7/KT77, 6550/KT88)

 

[Smilzo]

I wish a way to mix different tubes (not the output... the behaviuor) and a way to load "user tube". The more autentic the firmware, more subtle differnce shine trhu...

 

[J.C]

You should play around with a Boogie Mark series amp and some different tubes. I think you'd hear and feel a difference between El-34 and 6L6.

 

[Stratoblaster]

You should play around with a Boogie Mark series amp and some different tubes. I think you'd hear and feel a difference between El-34 and 6L6.

I'm finding a few Boogie amps in Cygnus that I can get on with now...never could bond with any Boogie amp previously. I'll definitely try out the various power tubes on them. I'd suspect I would indeed hear/feel some differences between those two tubes; they both are different species for sure.

Do you prefer one over the other in Boogies?

 

[J.C]

I'm finding a few Boogie amps in Cygnus that I can get on with now...never could bond with any Boogie amp previously. I'll definitely try out the various power tubes on them. I'd suspect I would indeed hear/feel some differences between those two tubes; they both are different species for sure.

Do you prefer one over the other in Boogies?

For Cleans, it's 6L6. For gain sounds, I buck the trend and prefer the El 34's. In the real Mark IV I go simul-class which has 2 of each. The differences are more obvious on the amp in the room, but I still notice a change in the Axe FX.

 

[IronSean]

This post is why I don't understand why the various tube types are even changeable parameters. If changing them doesn't change the sound, why include them at all?

They do have an effect, but when everything else is normalized the effect is subtle. Different tubes can have slightly different harmonic content behavior , especially when overdriven. But it's a lot more subtle when only the tube type changes vs real amps where a number of different parts of the amp align differently when you swap tube types without redesigning the whole thing.

 

[Fab8040]

5881 is a 6L6GC that's made to military spec so there's tighter quality control but they should otherwise be interchangeable.

Yeah i read about that.. I ve also read that not all 5881 are the same.. For example in the slo they where russian 5881.. Anybody knows which tubes are fractal refering to in the power amp section choice?

 

[LiamH]

Yeah i read about that.. I ve also read that not all 5881 are the same.. For example in the slo they where russian 5881.. Anybody knows which tubes are fractal refering to in the power amp section choice?

Not all of any given tube designation are the same, or for that matter labelled and sold under the intended designation, so Cliff will most likely need to be idealising the specification to some extent. Tubes of the same model number from different manufacturers can have significantly different internal structure. While many of the "corksniffer" tales tend to exaggerate how transformative of tone whichever rare and overpriced Mullard, Telefunken, RCA or whatever tube set is, they do make amps sound different from one another to varying extents.

Throw in on top of that: some of them might be "gassy", have screen resistors that have drifted in value, have varying degrees of microphonics, tube sockets that are not connecting perfectly, and a whole host of other unintended variables, and the omelette starts to become really quite complex. (Cliff, if you are reading, not sure anyone needs tubes half or completely failing to be modelled).

So neatly avoiding answering your question , I think in a lot of ways I prefer not to know. The last 20 years has been a minefield of mismatched tube brands and factories from all around the world, or see what you can find NOS that wasn't a reject, and if you are lucky you'll get a set that sounds good and is reliable (why is it that you could buy a 60s or 70s Marshall or Fender, still with original tubes, and go out and do 100 gigs straight without even thinking about tubes; late 80s onwards, you sometimes couldn't even set the bias without losing a tube?). I'm pretty happy just to know that modelled 5881 is a good 5881 specification (maybe RCA, GE or Philips), and that I can play with bias point and transformer matching without worrying about forking out for a new set because I have been running the plates too hot, or I got a matched set where one decided to prematurely commit suicide.

I'll bet I still have a brand new quad of matched EL34, a pair of 6V6, and probably a quad of 5881 or 6L6 GC in my spare tubes box, all of known reliability, or good quality NOS. I used to lose sleep over "what if" with power tubes, but for the last 5 years I've been using Axe FXes, and I am completely over it. This isn't yet perfect I am sure, but for me, it's close enough and getting closer all the time.

Liam