18W Tremolo TMB Xtra Gain build
Moderators: zaphod_phil, Daviedawg, Graydon, CurtissRobin, colossal
- JMPGuitars
- Super Duper Admin
- Posts: 3965
- Joined: Tue 09/18/12 8:00 pm
- Location: South Central, MA
- Contact:
Re: 18W Tremolo TMB Xtra Gain build
Your schematic is showing 470K grid leaks on the power tubes. Switch those to 220K and see how it sounds.
1 x
'I installed a skylight in my apartment yesterday... The people who live above me are furious.' - Steven Wright
Modern Ground Schemes
Soldering Technique
B+ Voltage Reduction
Amplifier Tools & Parts Info
Web Design: DolceVittoria.com
Guitars / Amps / Effects: JMPGuitars.com
(anti)Social: Facebook · Instagram
Items for Sale
Modern Ground Schemes
Soldering Technique
B+ Voltage Reduction
Amplifier Tools & Parts Info
Web Design: DolceVittoria.com
Guitars / Amps / Effects: JMPGuitars.com
(anti)Social: Facebook · Instagram
Items for Sale
- Bieworm
- Verbose Moderator
- Posts: 2302
- Joined: Mon 02/10/20 8:24 am
- Location: Belgium
Re: 18W Tremolo TMB Xtra Gain build
Thanks Josh... but I would like to maintain the Tremolo TMB sound when in parallel mode.JMPGuitars wrote: ↑Thu 02/24/22 11:25 amYour schematic is showing 470K grid leaks on the power tubes. Switch those to 220K and see how it sounds.
Will give it a shot anyway.. although it's a vox thang
0 x
"THIS should be played at high volume..preferably in a residential area"
- Bieworm
- Verbose Moderator
- Posts: 2302
- Joined: Mon 02/10/20 8:24 am
- Location: Belgium
Re: 18W Tremolo TMB Xtra Gain build
Sorry Josh.. but I tried a 100k Xtra Gain pot and it's spot on! Really nice crunch now.. even on full on dial. This is with the A500k Gain pot at 3 o'clock and the A100k Xtra Gain pot at 2 o'clock... rock on!!!
https://www.dropbox.com/s/ibba6h3d4iqr1 ... t.m4a?dl=0
https://www.dropbox.com/s/ibba6h3d4iqr1 ... t.m4a?dl=0
0 x
"THIS should be played at high volume..preferably in a residential area"
- JMPGuitars
- Super Duper Admin
- Posts: 3965
- Joined: Tue 09/18/12 8:00 pm
- Location: South Central, MA
- Contact:
Re: 18W Tremolo TMB Xtra Gain build
lol, no need to apologize. You can compensate for the gain issue in the preamp (which you did) or you can compensate in the power amp (or both). You may find you like it better one way or another, but you'll never know if you don't try.Bieworm wrote: ↑Thu 02/24/22 2:13 pmSorry Josh.. but I tried a 100k Xtra Gain pot and it's spot on! Really nice crunch now.. even on full on dial. This is with the A500k Gain pot at 3 o'clock and the A100k Xtra Gain pot at 2 o'clock... rock on!!!
https://www.dropbox.com/s/ibba6h3d4iqr1 ... t.m4a?dl=0
1 x
'I installed a skylight in my apartment yesterday... The people who live above me are furious.' - Steven Wright
Modern Ground Schemes
Soldering Technique
B+ Voltage Reduction
Amplifier Tools & Parts Info
Web Design: DolceVittoria.com
Guitars / Amps / Effects: JMPGuitars.com
(anti)Social: Facebook · Instagram
Items for Sale
Modern Ground Schemes
Soldering Technique
B+ Voltage Reduction
Amplifier Tools & Parts Info
Web Design: DolceVittoria.com
Guitars / Amps / Effects: JMPGuitars.com
(anti)Social: Facebook · Instagram
Items for Sale
- Bieworm
- Verbose Moderator
- Posts: 2302
- Joined: Mon 02/10/20 8:24 am
- Location: Belgium
Re: 18W Tremolo TMB Xtra Gain build
you're right! it's pretty easy to try when I parallel another 470k resistor with the EL84 grid leak resistors..JMPGuitars wrote: ↑Thu 02/24/22 4:32 pmlol, no need to apologize. You can compensate for the gain issue in the preamp (which you did) or you can compensate in the power amp (or both). You may find you like it better one way or another, but you'll never know if you don't try.Bieworm wrote: ↑Thu 02/24/22 2:13 pmSorry Josh.. but I tried a 100k Xtra Gain pot and it's spot on! Really nice crunch now.. even on full on dial. This is with the A500k Gain pot at 3 o'clock and the A100k Xtra Gain pot at 2 o'clock... rock on!!!
https://www.dropbox.com/s/ibba6h3d4iqr1 ... t.m4a?dl=0
thanks for your input!
1 x
"THIS should be played at high volume..preferably in a residential area"
- JMPGuitars
- Super Duper Admin
- Posts: 3965
- Joined: Tue 09/18/12 8:00 pm
- Location: South Central, MA
- Contact:
Re: 18W Tremolo TMB Xtra Gain build
Another thing you can do is the stupid simple master volume. Play around, and when you're done, measure the resistance you like the best at the grid leaks.
Obviously if you drop the volume with that too much, you lose power amp distortion.
Thanks,
Josh
You do not have the required permissions to view the files attached to this post.
1 x
'I installed a skylight in my apartment yesterday... The people who live above me are furious.' - Steven Wright
Modern Ground Schemes
Soldering Technique
B+ Voltage Reduction
Amplifier Tools & Parts Info
Web Design: DolceVittoria.com
Guitars / Amps / Effects: JMPGuitars.com
(anti)Social: Facebook · Instagram
Items for Sale
Modern Ground Schemes
Soldering Technique
B+ Voltage Reduction
Amplifier Tools & Parts Info
Web Design: DolceVittoria.com
Guitars / Amps / Effects: JMPGuitars.com
(anti)Social: Facebook · Instagram
Items for Sale