I'd like to add a tone control to a Fender Acoustasonic Tele. Stock it has a volume and "blend" control but no tone control. Adding a passive tone control (treble roll-off) does not seem like a daunting project. What do you think?
Thanks
Search found 182 matches
- Mon Dec 18, 2023 10:14 pm
- Forum: Garage Talk
- Topic: Tone control for acoustasonic Tele
- Replies: 1
- Views: 1261
- Fri Feb 10, 2023 1:40 am
- Forum: Fender Discussion
- Topic: AA764 Champ Farts Out, help!
- Replies: 4
- Views: 1387
Re: AA764 Champ Farts Out, help!
Turns out it was the Tubes after all. Replaced the old tubes with new and now it should like a Champ. And the TSB switch adds a nice crunch.
Thanks, everyone for your help and advice. I'm going to try the cap value adjustments too.
Thanks, everyone for your help and advice. I'm going to try the cap value adjustments too.
- Wed Feb 08, 2023 10:33 pm
- Forum: Fender Discussion
- Topic: AA764 Champ Farts Out, help!
- Replies: 4
- Views: 1387
AA764 Champ Farts Out, help!
1966 Fender black-face Champ (non-vibrato). All new electrolytic caps, new 8" MOD speaker. The only mod is a tone stack bypass switch. The circuit is stock with the TSB turned off. The amp farts out significantly at medium and above volume with/without the TBS engaged. Tubes are original by test goo...
- Fri Apr 17, 2020 7:55 pm
- Forum: Technical Discussion
- Topic: Rectifier help
- Replies: 24
- Views: 2067
Re: Rectifier help
With the 150r bias resistor, the plate dissipation is down to 9w, which seems very safe for a JJ 6v6 (14w max) in a class A application. Also, I changed the bypass cap on V1 to improve the highs and I like it better. The amp is working fine.
Thanks for all your help and advice.
Thanks for all your help and advice.
- Tue Mar 31, 2020 12:56 am
- Forum: Technical Discussion
- Topic: Rectifier help
- Replies: 24
- Views: 2067
Re: Rectifier help
Power Tube (EL-84 ) voltages:
Plate (pin 7) 257vdc
Cathode (pin 3) 6.5vdc
Screen Grid (pin 9) 249vdc
Control Gri (pin 2) .137vdc
Voltage drop across the Cathode resistor: 6.5vdc
Cathode resistor value is 120 R
267 vdc (B+) from the rectifier
Plate (pin 7) 257vdc
Cathode (pin 3) 6.5vdc
Screen Grid (pin 9) 249vdc
Control Gri (pin 2) .137vdc
Voltage drop across the Cathode resistor: 6.5vdc
Cathode resistor value is 120 R
267 vdc (B+) from the rectifier
- Sat Mar 28, 2020 11:19 pm
- Forum: Technical Discussion
- Topic: Rectifier help
- Replies: 24
- Views: 2067
Re: Rectifier help
OK! with the rectifier circuit change per Martin's modded layout, the voltages are now within a couple of volts of those on the original schematic. Thanks for your help! Do you have any advice on how to get this circuit to be more "chimey" and no so mid-range heavy? I am hoping to get more that EL-8...
- Thu Mar 26, 2020 1:47 am
- Forum: Technical Discussion
- Topic: Rectifier help
- Replies: 24
- Views: 2067
Re: Rectifier help
Even if i have only one El-84 installed?
- Wed Mar 25, 2020 4:33 pm
- Forum: Technical Discussion
- Topic: Rectifier help
- Replies: 24
- Views: 2067
Re: Rectifier help
Martin, that's how I had it originally, which made more sense to me but I was only getting 245vdc B+ and the amp had no punch at all, after changing to it, the vdc went up over 100vdc and it sounds much better, but I'm thinking of adding a diode to lower the B+ a bit. I still like your circuit bette...
- Mon Mar 23, 2020 8:24 pm
- Forum: Technical Discussion
- Topic: Rectifier help
- Replies: 24
- Views: 2067
Re: Rectifier help
Here is the schematic
- Mon Mar 23, 2020 8:15 pm
- Forum: Technical Discussion
- Topic: Rectifier help
- Replies: 24
- Views: 2067
Re: Rectifier help
Posted in error
- Mon Mar 23, 2020 12:17 am
- Forum: Technical Discussion
- Topic: Rectifier help
- Replies: 24
- Views: 2067
Re: Rectifier help
this is how it's wired now. This is from Mat's 86 Special layout from a few years ago. I added an additional EL84 in series to make it dual single-ended.
- Sun Mar 22, 2020 10:25 pm
- Forum: Technical Discussion
- Topic: Rectifier help
- Replies: 24
- Views: 2067
Re: Rectifier help
Thanks, I don't understand why but moving the ground from the center tap of the transformer to the negative side of the rectifier fixed the issue. i now have 379 vdc out of the rectifier. I was mistaken about the diodes, they are N40007 rather than 40001. Ultimately, I'm trying to find out why this ...
- Sun Mar 22, 2020 8:19 pm
- Forum: Technical Discussion
- Topic: Rectifier help
- Replies: 24
- Views: 2067
Rectifier help
I have a Hammond 269EX going to two N4001 diodes to form a bridge rectifier. The center tap of the B+ is going to ground. I have 205vac per side into the diodes but only 245vdc coming out. I could change the rectifier to full bridge, adding two more diodes, lift the center tap ground from the transf...
- Mon Apr 10, 2017 6:41 pm
- Forum: Fender Discussion
- Topic: fender deluxe homemade too bright and clean
- Replies: 9
- Views: 2121
Re: fender deluxe homemade too bright and clean
If you have 170v or more on the plates of the pre-amp tubes you could try dropping the voltage off the power rail at “B” so you get closer to 100v on those plates, that will brown up the amp and give you earlier breakup. Also, you could try changing the rectifier tube to a NOS tube and see as much a...
- Thu Sep 15, 2016 5:13 pm
- Forum: Technical Discussion
- Topic: Gretsch 6150t Supro 16t amplifier build
- Replies: 3
- Views: 2081
Re: Gretsch 6150t Supro 16t amplifier build
Nice build, You could use a power resistor for impedance matching too. I use these for impedance matching when building attenuators. You could paint the inside of the apexjr clear pilot jewel and get that milky white glow similar to the valco amp. The white jewel from AES is close to the correct loo...