• TalkBass has been independent since 1998. Add your voice.
    Create a free account to reply to discussions, view embedded media, and browse with fewer display ads.
    Join free Log in
    Want zero display ads or expanded classifieds tools? Compare plans.

Preamp tube section on head - how long for warmup?

#41
Super Bass said:
The JJ's are pretty typical sounding 12AX7's....
Click to expand...

Depends on their use IME. In classic 4-hole Marshalls, they're my favorites, especially in the first and phase inverter positions. They do the old-school, mid-range punch thing better than the Gold Lions, especially when using the amp, not pedals, for overdrive tones.

Sample clips from past gigs, JJ ECC83s spiral filament 12AX7's and EL34 power tubes. Amps have usable master volume controls. No pedals on 1st two clips, a clean boost on the second verse of clip #3.

50w Marshall plexi clone:



50w Marshall bass/1986 plexi:



50w plexi clone:

 
  • Like
Reactions: toan4dayz, Bill Whitehurst and Super Bass
#42
Kyley Boyd said:
I have the GK fusion with 3 tubes. Takes about 20 seconds before any sound will come out. After a few minutes it sounds even better. Sorry I don’t know enough about the issue to help.
Click to expand...
I've been using a GK MB800 Fusion (into a Berg 410) for several years now, and I've noticed that it seems to take several minutes (like 15-20) for the preamp section to sound as though it's warmed up and running on all cylinders. Have you or anyone else experienced this?
 
#44
I've been using a GK MB800 Fusion (into a Berg 410) for several years and it seems like it takes several minutes (like 15-20) for the tone section to manifest and sound "warmed up". At that point it sounds great. Have you or anyone else experienced that?
 
#45
AntiTreble said:
I've been using a GK MB800 Fusion (into a Berg 410) for several years and it seems like it takes several minutes (like 15-20) for the tone section to manifest and sound "warmed up". At that point it sounds great. Have you or anyone else experiencedd that?
Click to expand...
No, and there are no tubes in the MB800.
 
#49
AntiTreble said:
I've been using a GK MB800 Fusion (into a Berg 410) for several years now, and I've noticed that it seems to take several minutes (like 15-20) for the preamp section to sound as though it's warmed up and running on all cylinders. Have you or anyone else experienced this?
Click to expand...
Yes, many times. Although in theory it could be anything, what you describe is a typical symptom of one or more weak preamp tubes. Sounds like there's a veil over your tone, poor dynamics, no life, no "grunt". The sound is just... "there". However, before you proceed with a tube swap, connect the effects send and return jacks together and see if things improve. Probability of that being the problem is extremely low, but it's a cheap, quick, zero-potential-for-damage test you should do first. I've never been inside a Fusion so I can't advise you on what cautions to observe WRT potential physical damage during a tube swap. Wouldn't surprise me if that topic's already been discussed somewhere.
 

Latest posts

Top Bottom
Back