Preamp tube question

[Guitarist-Jonny]

Hi dudes and dudettes- I'm just wonderin...
A) How much effect does the AMOUNT of preamp tubes (e.g. 12AX7) affect your sound? What if your using a multi effects machine before the amp?
B) How much of a sound difference will there be between an amp with say 4 12AX7 preamp tubes & 4 6L6GC power tubes and an amp with 4 12AX7 preamp tubes & 4 EL34 tubes with/without an effects processor/ multi effects before the amp?

All replies are greatly appreciated
Regards
Jonny

[Vim Fuego]

Well, of course the glib answer is... it depends, and, do whatever you think sounds best!
I know that when Joe Satriani was developing the JSX amp he made sure that it worked well with the effects he would put in front of it, tubescreamer, whammy etc. The inference being that some amps, particularly high gain amps, don't respond too well to having additional distortion/overdrive plugged in the front.
Interestingly on a G3 video I saw, Steve Vai and Joe Satriani were discussing this exact issue and commenting on the relative benefits of the tube screamer and boss DS-1 distortion. Steve Vai is working on a combined dual distortion/overdrive pedal with Ibanez at the moment called the jemini.
From my experience, for the last decade I have never used an overdrive pedal or the overdrive section of a multi effects. I always use the valve distortion from my Laney VH100R amp. I always thought this was how it should be done, but *most* people seem to use an overdrive/distortion pedal in front.
I have a GT-8 multi effects which I wire up using the "4 cable method" this means that the signal goes from the guitar to the front of the GT-8, GT-8 send to the front of the amp, amp send to the return of the GT-8, GT-8 output to the return of the amp.
This means some GT-8 effects can be in front of the amp e.g. Wah, compression, then you get the Laney pre-amp, then you get delay, chorus, reverb etc. after the pre-amp.
As you can move the location of the send and return in the effects chain on the GT-8, you can change which effects are pre or post amp pre-amp.
As regards the power amp valves. I changed from 6L6s to EL34s years ago and have never changed back, although in honesty I can't remember the sound being bad before!
Jim
'98 Jem7VWH
'91 Jem77BFP with GK-3
RG470FMR
Charvel EVH Art Series (red/white/black)
Burns Brian May
Epiphone G-1275 double neck
Epiphone Sheraton II

Laney VH100R
Boss GT-8
Roland GR-30
Roland VG-88
etc. etc....

[bammbamm]

Instead of listing the tube config, it might help if you list the amp you're using.
You could have a Mesa with 4 12AX7s and a pair of 6l6s sound chunky as fat Albert, and a Fender Twin will be spanky clean with the same or similar config.

Gain structures differ from amp to amp.

[Guitarist-Jonny]

Thanks for the reply dudes , I'm using a Peavey Valveking at the mo but I find the distortion only cuts right with the bright switch in w/ the ME50 METAL distortion, I'm using a Yamaha Pacifica 821D as my main guitar (Flame maple top, Alder Body, Maple neck/ rosewood board, bolt on, Dimarzio Air Classic pickups) Also when its turned up i cant seem to get the sound i get wen its lower in volume: its either too 'muffy' or too tinny . I'm lookin for a way to get a good sound without keepin my amp right down or turnin it WAY up- which leads me to asking whats the optimum volume for an amp? Obviously this could seem like a silly question but I'm thinkin- If I'm using a PA etc, what volume shud my amp be at to get a good quality sound without drivin the tubes too much? Because logic would tell me to configure all my settins and stuff to work best at this volume Sorry for all the questions. Ur help is much appreciated!
Regards
Jonny

[Vim Fuego]

It sounds like you're getting most of your best sound from a combination of the ME50 and the Valveking's Power valves.
If you're happy with the sound at high volumes then you could consider using a power attenuator such as the Marshall Powerbrake. This goes in parallel with your speakers and soaks up some of the power while keeping the load on the amp correct. This way you get less output from the speaker but the power stage of the amp can be running flat out which generally sounds better.
You could try backing off the gain on the Valveking pre-amp if you're hapy with the sound from the ME50 so you're almost using the Valveking as a clean power amp only.
Jim
'98 Jem7VWH
'91 Jem77BFP with GK-3
RG470FMR
Charvel EVH Art Series (red/white/black)
Burns Brian May
Epiphone G-1275 double neck
Epiphone Sheraton II

Laney VH100R
Boss GT-8
Roland GR-30
Roland VG-88
etc. etc....

[bammbamm]

Yup power attenuator will do you right. Scholz Power soak or a Hot Plate.

[Guitarist-Jonny]

Cud the 'tinniness' of the amp at high volumes be caused by the cab speakers movement/shaking? How much and where cud i get a power attenuator please? How is the amps sound different when the tubes are driven hard? by running my amp as a clean power amp- wud the power tubes (6l6GC) still make a difference to my sound? I think it does but i have to be sure sorry lol. If it does affect my sound how much difference wud ther be and what tonal differences wud i find if i installed EL34s instead?
Thanks
Regards
Jonny

[bammbamm]

Tinny-mess I would think would be a tonal adjustment, not the speakers shaking. That is what they're designed to do. If they are moving with a wide excursion, you'll get more rumble than anything else.

You'll have to see what you like better about your output tubes.
I used to prefer EL-84's, but now I'm a staunch EL-34 guy.
It's pref.

[Vim Fuego]

Of course there is a well-known (by some!! ) effect by the name of 'Fletcher–Munson' (http://en.wikipedia.org/wiki/Fletcher-Munson_curves) this states that the ear is less sensitive to high and low frequencies at low sound levels. So you will naturally boost the lows and highs compared to the mids when your amp is quiet. When you turn up the ear becomes more sensitive to the high and low frequencies and the amp starts to sound both "tinny" and "woofy" (http://line6.com/support/entry.jspa?externalID=3787)
Maybe this is part of the problem?
Jim
'98 Jem7VWH
'91 Jem77BFP with GK-3
RG470FMR
Charvel EVH Art Series (red/white/black)
Burns Brian May
Epiphone G-1275 double neck
Epiphone Sheraton II

Laney VH100R
Boss GT-8
Roland GR-30
Roland VG-88
etc. etc....

[Guitarist-Jonny]

That's an awesome explanation dude cheers! So basically tek my treble and bass down wen its high in volume . Thanks dudes . Does each tube have a sort of genre where its most used? If so, where are the 6l6, EL84 and EL34 each mostly used?
regards
Jonny

[Vim Fuego]

Well... most amps use ECC83 (12ax7) in the pre-amp, rarely ECC82 in the power amp driver.
EL34s give about 25 watts each so you'd have 2 in a 50W amp 4 in 100W. These are usually used in "British" amps - Marshall Hiwatt Laney etc.
EL84s give about 7 watts each so 2 would be 15W and 4 would be 30W. These are usually used in amps like AC30s, Matchless and other boutique low wattage amps (They are often used in class A/B mode).
6L6GC (5881) give about 30 watts each. Usually used in "American" amps like Boogie, Fender, Peavey etc.
You can use 6L6 or EL34 interchangably provided you can adjust the Bias voltage for the power amp valves, some amps do this automatically, some use a pot and some have a switch.
Jim
'98 Jem7VWH
'91 Jem77BFP with GK-3
RG470FMR
Charvel EVH Art Series (red/white/black)
Burns Brian May
Epiphone G-1275 double neck
Epiphone Sheraton II

Laney VH100R
Boss GT-8
Roland GR-30
Roland VG-88
etc. etc....

[Guitarist-Jonny]

Thanks so much dude! Just one more question- what will the sound difference between 3 12 AX7's and 4 if the amp is structured the same? thanks
regards
Jonny

[bammbamm]

Ha, it's a trick question !
It would sound exactly the same because in both cases there would be 3 12ax7s !

I win.

[Guitarist-Jonny]

Wat do u mean sorry lol? How wud they both have 3 12AX7s? is it coz i sed they wer structured the same? Sorry i jst dnt understand lol
regards
Jonny

[toshiro]

Depends on how the amp uses that extra tube. If it's using it as a effects loop buffer, or something, there will be little difference.

On the other hand, if it's adding gain stages, you just went up by as much as 2.