Search found 66 matches

by two tone
Sun May 26, 2024 1:38 pm
Forum: Marshall Discussion
Topic: Friedman Plex
Replies: 0
Views: 145

Friedman Plex

Looking for gutshots, anyone?
by two tone
Sun Apr 28, 2024 1:03 pm
Forum: Dumble Discussion
Topic: #54 (photos)
Replies: 46
Views: 12006

Re: #54 (photos)

A 12AX7 sounds brighter than a 12AT7
by two tone
Mon Jan 08, 2024 10:03 pm
Forum: Technical Discussion
Topic: "EF86" sound from 12AX7 tube?
Replies: 7
Views: 9615

Re: "EF86" sound from 12AX7 tube?

Actually the Top Boost Vox installed later, comes pretty close to the tone of an EF86. (set the Treble and Bass Pots to zero or very low)
by two tone
Thu Sep 28, 2023 10:16 am
Forum: Technical Discussion
Topic: Fetron
Replies: 37
Views: 18252

Re: Fetron

6C248C35-6E21-4188-82B4-C81E4C5195E3.jpeg
8B4C39C7-2B5F-4301-923C-251BEE97BB8E.jpeg
from the manual..
by two tone
Wed Sep 27, 2023 9:19 am
Forum: Technical Discussion
Topic: Fetron
Replies: 37
Views: 18252

Fetron

3C8686AB-DDC0-40D9-BDCE-801C7C201548.jpeg
B33A4AB3-D46D-4146-B21D-46E8DF7A9EB5.jpeg
Rare find from a 1977 Mesa Boogie
by two tone
Wed Sep 06, 2023 8:07 am
Forum: Technical Discussion
Topic: Clean Reverb
Replies: 4
Views: 483

Re: Clean Reverb

I do. I split the signal coming from the guitar. A is going to fet booster into Dumble Style amp ,B goes to tuner and a Delay pedal ( 100%wet) into a 5 w Combo . Love it
by two tone
Tue Jul 04, 2023 12:41 pm
Forum: Dumble Discussion
Topic: VHT Fet Boost
Replies: 1
Views: 531

VHT Fet Boost

I bought a VHT D-Boost recently, here is my review. Accurate take on the Fet Circuit of a Dumble. Uses a 2N4416A JFet and a LT1054 Voltage Converter. With a Power Supply of -12v I got 22v on top of the Drain Resistor (10k),16,5v at the Drain and 2,7 v at the Source. Lowering the Source Resistor from...
by two tone
Mon May 22, 2023 6:19 pm
Forum: Dumble Discussion
Topic: The plate to cathode cap
Replies: 33
Views: 4318

Re: The plate to cathode cap

If my memory serves me well, the Fuchs ODS had 470p snubbers
by two tone
Thu Mar 23, 2023 10:58 pm
Forum: Technical Discussion
Topic: OPT driven reverb into second amp input
Replies: 8
Views: 1050

Re: OPT driven reverb into second amp input

I‘ve been doing this for some years now. Add a resistor between the speaker out and the reverb in( 50/100ohm in series) .This isolates the reverb from the amps output impedance. I‘m running 50 w amps at stage volume into the reverb pan feeding a small satellite amp( 5-10w) . Dry/Wet system
by two tone
Mon Feb 20, 2023 9:07 am
Forum: Technical Discussion
Topic: W/D/W Using The FX-Loop Vs. A "Line Out Box"?
Replies: 34
Views: 2324

Re: W/D/W Using The FX-Loop Vs. A "Line Out Box"?

Build one yourself, it‘s only a pot and a resistor
by two tone
Mon Oct 31, 2022 4:41 pm
Forum: Technical Discussion
Topic: Circuit Analysis Jim Kelley Amp
Replies: 22
Views: 7350

Re: Circuit Analysis Jim Kelley Amp

Having 2 Jim Kellys, I can say ,it‘s not a problem with JJ‘s.One has 470v, the other about 460v on the plates.
High Plate Voltages are not so much problematic,High Screen Voltages can be.
These are great amps!
by two tone
Tue Mar 09, 2021 8:17 am
Forum: Dumble Discussion
Topic: High Plate Classic? Should We build it.
Replies: 47
Views: 6304

Re: High Plate Classic? Should We build it.

1M Trimmer with 150k to ground equals 100k trimmer with 40k to ground.Add the 220k ,there is a 7:1 ratio ( 280k:40k / 1070k:150k) so 12,5% Signal feeding OD 1
by two tone
Mon Mar 08, 2021 3:15 pm
Forum: Dumble Discussion
Topic: High Plate Classic? Should We build it.
Replies: 47
Views: 6304

Re: High Plate Classic? Should We build it.

I have a schem of #094 with a 1M OD Trimmer, 152k to ground,100k pots