Search found 92 matches
- Sat Feb 09, 2013 8:21 pm
- Forum: Technical Discussion
- Topic: Please help. (Weird acting input resistance)
- Replies: 12
- Views: 1737
Re: Please help. (Weird acting input resistance)
Did you put back the same resistor you took out? It sounds like you put back a much lower value resistor, maybe 4k7 or 470 ohms. The pedal has a low enough output impedance that it can drive that low of an input impedance, but it would make a regular guitar output sound dull and weak. 470k should be...
- Sat Jan 19, 2013 4:05 am
- Forum: Technical Discussion
- Topic: Volume Pot Taper On Vox AC 30
- Replies: 6
- Views: 3074
Re: Volume Pot Taper On Vox AC 30
Bourns has amp pots also.
- Thu Sep 06, 2012 7:06 pm
- Forum: Technical Discussion
- Topic: where to go to to have faceplates made?
- Replies: 38
- Views: 8861
Re: where to go to to have faceplates made?
Jeanne at BNP and Sandy at Precision Design are both top drawer. Highly recommended.
- Sat Aug 04, 2012 1:15 am
- Forum: Technical Discussion
- Topic: Acoustic Bolt on Neck
- Replies: 16
- Views: 4709
Re: Acoustic Bolt on Neck
Certain Epiphone acoustics from the '70s had bolt-on necks similar to an electric bolt-on.
- Fri Jul 20, 2012 3:33 am
- Forum: Technical Discussion
- Topic: Ampeg GVT15 - What circuit is that?
- Replies: 2
- Views: 1808
Re: Ampeg GVT15 - What circuit is that?
My guess would be a bridged-T filter with the pot in the bottom for more or less mid cut.
If you ask Pyotr nicely, he might just tell you.
If you ask Pyotr nicely, he might just tell you.
- Thu Mar 08, 2012 2:15 pm
- Forum: Technical Discussion
- Topic: Fake PI
- Replies: 16
- Views: 3627
Re: Fake PI
Couldn't you do something with zeners and regular diodes to simulate the grid conduction? Maybe something like this:You will have a helluva time emulating power tube grid conduction without having a power tube to cause stuff to clip earlier.
- Wed Nov 09, 2011 2:43 pm
- Forum: Technical Discussion
- Topic: Tone Stack Simulator and "Designer"
- Replies: 1
- Views: 1156
Re: Tone Stack Simulator and "Designer"
Grab a (free) version of SPICE or pSPICE and model your circuits. It won't give you the interactive control like the TSC, but you can run frequency plots at various settings to get a visual of what your stack is doing. I used B2 Spice Lite to model the D-stack and make some changes that bring it mor...
- Fri Oct 28, 2011 7:28 pm
- Forum: Technical Discussion
- Topic: Transformerless Reverb
- Replies: 10
- Views: 4662
Re: Transformerless Reverb
I "borrowed" the design that Carvin uses in their Vintage series of amps for a D-style amp conversion. I bought an Accutronics/Belton tank with the high input impedance, and used a single 12DW7 -- the 12AU7 side for the drive and the 12AX7 side for the makeup. Worked well enough, not surf quality, b...
- Mon Oct 17, 2011 8:19 pm
- Forum: Garage Talk
- Topic: adams amps malware?
- Replies: 2
- Views: 1493
Re: adams amps malware?
Yeah, I got the same message last week. I used the wayback machine to find the info I was looking for at that site. I don't know if the site is actively maintained, but I hope it can be remedied.
- Mon Aug 29, 2011 9:41 pm
- Forum: Technical Discussion
- Topic: Running My Fender Hotrod Deluxe without powertubes?????
- Replies: 11
- Views: 1891
- Mon Aug 29, 2011 8:43 pm
- Forum: Technical Discussion
- Topic: Running My Fender Hotrod Deluxe without powertubes?????
- Replies: 11
- Views: 1891
Re: Running My Fender Hotrod Deluxe without powertubes?????
Stick a shorted plug into the power amp in jack and that should kill the sound.
- Mon Aug 29, 2011 8:41 pm
- Forum: Technical Discussion
- Topic: Tweed Overdrive w/2CF
- Replies: 3
- Views: 1177
Re: Tweed Overdrive w/2CF
Know, too, that unless explicitly stated otherwise, these are all built, tested, and tweaked designs. I know 10thTx spends a lot of time getting the right combination of clarity, note bloom, touch sensitivity, harmonics, etc., at least for his own sensibilities, in each of these designs. He is indee...
- Tue Jul 19, 2011 7:36 pm
- Forum: Technical Discussion
- Topic: Seeking more clean power from this design
- Replies: 44
- Views: 9523
Re: Seeking more clean power from this design
Check the other 56K (the cathode resistor). Make sure you've got a good ground. Also check the 1K. With only a 6V drop, it seems like something is way out of spec or not properly connected. Yes, you should have about 300v on the plate and about 50v on the cathode. As measured, you're only flowing a...
- Tue Jun 28, 2011 10:28 pm
- Forum: Technical Discussion
- Topic: Finding the Right OT - Quad of EL84
- Replies: 11
- Views: 3204
Re: Finding the Right OT - Quad of EL84
Unless you plan on going ultra-linear, the Dynaco is overkill. The TW OT is also perhaps not the best choice at 6k6 primary impedance. You could actually get by with the Fender HRD or Bassman OT at Triode Electronics. The Allen TO35MT or TO40MT would also work.
- Fri Mar 11, 2011 3:48 pm
- Forum: Technical Discussion
- Topic: Where do I measure bias voltage?
- Replies: 8
- Views: 1913
Re: Where do I measure bias voltage?
Yes, you can leave the 1 ohm resistors in permanently.
When measuring, be aware that the cathode current contains both the plate and screen current.
When measuring, be aware that the cathode current contains both the plate and screen current.