ADA Depot - A Forum To Support Users of ADA Amplification Gear

Please login or register.

Login with username, password and session length
Advanced search  

News:

Lets get Technical > All Things Tube All about preamp and power amp Tubes.

Pages: [1]   Go Down

Author Topic: Tube Cocktail  (Read 7357 times)

0 Members and 1 Guest are viewing this topic.

Dante

  • Administrator
  • Superhero Member
  • ******
  • Offline Offline
  • Posts: 2124
  • Nothing more uncommon than common sense
    • The Best Cover Band In Sacramento
Tube Cocktail
« on: Time Format »

In case anyone else wants to try to get that 'brown sound' out of a stock MP-1 by trying differing low-gain tubes, here's a post that I revived from inky depths of internetdom:

I found this from my old 'Tube Cocktail' post on the old Depot (in 2009):
Quote
I have read elsewhere on the board about putting the higher gain tube into V1 and a lower gain tube into V2, so I tried that. I put a JJ 12AX7 (high gain) into V1 and began trying all sorts of other tubes in V2.

Sylvania 12AX7 (low noise): Low noise my a$$! It was a mess, too noisy, too much gain (not in a good way)
JJ 12AU7: Excellent for low-gain rhythms, but a bit too clean. I couldn't get enough "hair" on the tone to use for solos.
GE 12AY7: PERFECT! I can get the low growl of my ol' JCM800 with ease. It's kinda like a MOD-1 with a bit more gain or "hair" on the edges. I love it. Since this tube is NOS (c. 1959) I'm ordering a newer JJ 12AY7 to put in there.

Gear used during testing: MP-1 directly into the input jack of my Musicman combo (112RD, 50 watt, SolidState preamp section, Tube Power section - 2 6L6s) running as clean as possible, no bright switch, EQ was flat.

and a few days later...

Quote
Well guys, I received the newer 12AY7 from TubeDepot.com and put it into my MP-1. I am happy to say it has the same result as the 50-year-old NOS GE tube I had in it.
« Last Edit: Time Format by Dante »
Logged

rnolan

  • Administrator
  • Superhero Member
  • ******
  • Offline Offline
  • Posts: 5998
Re: Tube Cocktail
« Reply #1 on: Time Format »

Dante, you tube roller you  :whoohoo!:
Logged
Studio Rig: Stuff; Live Rig: More Stuff; Guitars: A few

Axemane

  • Newbie
  • *
  • Offline Offline
  • Posts: 35
Re: Tube Cocktail
« Reply #2 on: Time Format »

I have two brand new groove tubes silver series 12AX7's. Chinese I think. Anyone ever troed these in a stock mp-1 ?
Logged

rnolan

  • Administrator
  • Superhero Member
  • ******
  • Offline Offline
  • Posts: 5998
Re: Tube Cocktail
« Reply #3 on: Time Format »

Hey Axemane, Haven't tried them personaly but they should be pretty good. GT do a fair bit of testing before they stick their name on a tube.  The original MP1 tubes (and MP2) were Chinese although no brand, they were great tubes.  I've heard mixed reports about Chinese tubes (some good some bad) but, as I say, if GT are putting their name on it it will be a good tube.  Put them in and see (hear) how they go, and let us know how you get on.
Cheers Richard
Logged
Studio Rig: Stuff; Live Rig: More Stuff; Guitars: A few

kawai2g4b

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 272
Re: Tube Cocktail
« Reply #4 on: Time Format »

Hey Dante,

I read that you originally did the tube test through the Music Man combo, this got me thinking...

Currently I have a Music Man HD130 with original Sylvania 6CA7s which serves as my main tube bass head, though it is equally if not more renowned as a guitar head, especially for country players.  If I remember right, those Music Mans all shared the same preamp circuitry, which my active basses tend to overrun if I don't turn the volume down.  Anyway, what did you have the ADA preamp output set to and how did you dial up the gain on the MM preamp and would that prevent damage if used during extended periods of time?
Logged
Pearce G2R with ADA TFX4 in loop.
ADA MB-1/B500B
And other non ADA stuff.

Kawai AQ-500 guitar, Korean Fender Lite Ash Strat, Electra X930 MPC modded, G&L L2K basses, Peavey T40, Fernandes basses.

Dante

  • Administrator
  • Superhero Member
  • ******
  • Offline Offline
  • Posts: 2124
  • Nothing more uncommon than common sense
    • The Best Cover Band In Sacramento
Re: Tube Cocktail
« Reply #5 on: Time Format »

I ran out of the recording out, directly into the input. I always planned on having the 'line out' jack in the back converted to a 'pwr amp in' jack, bypassing the preamp stage altogether. My local amp tech said he would do it for me, but I never got it done.

rnolan

  • Administrator
  • Superhero Member
  • ******
  • Offline Offline
  • Posts: 5998
Re: Tube Cocktail
« Reply #6 on: Time Format »

Does the MM have a loop return ?  sometimes you can bypass the preamp by going into the loop return (depending where it is in the signal chain) although this didn't work well for Steve (RandallRG) and his Randall head(s).

If you have an early MP1 you can use the switch on top to turn the output to instrument level and plug into the MM clean channel and make the eq as flat as possible.  If line level out of MP1 then turn MP1 output right down and MM clean input vol down so you don't overdrive the MM preamp, again eq as flat as possible.  Interesting note on eq in guitar amps, in the ADA APP1 manual (which I posted here somewhere (or download it from A/DA site)) they have some suggested eq settings for various amps to make them flat as possible (interesting as these suggested settings aren't necessarily what you would think e.g. all at half), if they don't list a MM, fender twin settings should be similar.

There's also some other posts (Guitar George I think) which recommend a decent level converter (Ebtech, line to inst, inst to line)
Logged
Studio Rig: Stuff; Live Rig: More Stuff; Guitars: A few

kawai2g4b

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 272
Re: Tube Cocktail
« Reply #7 on: Time Format »

The HD130 does not have a loop or preamp bypass.  I would have to do it like Dante did and with your added recommendations.  Hopefully will be the key to avoiding purchasing a tube power amp in the future.
Logged
Pearce G2R with ADA TFX4 in loop.
ADA MB-1/B500B
And other non ADA stuff.

Kawai AQ-500 guitar, Korean Fender Lite Ash Strat, Electra X930 MPC modded, G&L L2K basses, Peavey T40, Fernandes basses.

rnolan

  • Administrator
  • Superhero Member
  • ******
  • Offline Offline
  • Posts: 5998
Re: Tube Cocktail
« Reply #8 on: Time Format »

If you keep the levels under raps it should be fine, obviously line level loop returns (if they work as planned) or power amp ins are better matched....
Hopefully will be the key to avoiding purchasing a tube power amp in the future.
try this one, (http://www.carvinworld.com/products/DCM200L) even cheaper than I initially thought, and 2 cabs (run it stereo, it's awesome)
Logged
Studio Rig: Stuff; Live Rig: More Stuff; Guitars: A few

kawai2g4b

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 272
Re: Tube Cocktail
« Reply #9 on: Time Format »

Ideally you are right.  My budget is a bit cramped right now.  I could look into a power amp in jack mod but I will have to look into that cost.
Logged
Pearce G2R with ADA TFX4 in loop.
ADA MB-1/B500B
And other non ADA stuff.

Kawai AQ-500 guitar, Korean Fender Lite Ash Strat, Electra X930 MPC modded, G&L L2K basses, Peavey T40, Fernandes basses.
Pages: [1]   Go Up