Recent content by DadTheTinkerFairy

I’m going to experiment with the jfet bias as well. I set them to 4.5v but saw another thread that they should be set to 5.875 for Q1 and 6.345v for Q2.

Thanks! We definitely more attention to acoustic gear in the DIY community. The available acoustic preamps are stupidly expensive for what they are, no reason we can’t build them ourselves.

I decided to socket C3, C5, and C14 to experiment. Turns out C3 and C5 don’t have nearly the effect I I thought they do. They mostly serve to reduce the noise floor and only slightly reduce presence treble frequencies. I may just reduce these from 3.3nf to 2.2nf. The big culprit turned out to...

I built a Capsize preamp to experiment using with my acoustic. It has a Fishman magnetic sound hole pickup, not piezo. It is a pretty low output pickup so I was looking for something to clean boost and add a bit of tone shaping. I also added a buffer/inverter for an XLR balanced output. It works...

This thing RIPS !! Just have to decide how to label the knobs.

I tore this thing down because I wanted to replace the volume pot with an audio taper, so I removed C6 while I was at it and that was definitely what was making it so dark. I suppose it is tuned to be used into a really bright amp, but the 2n2 cap makes the tone control so it doesn’t have very...

I have built a Stagecoach (Barber BUSS) and I really like it except even with the tone knob all the way up, it doesn’t have much treble and no presence at all. I’m wondering if this is normal for this circuit. And, what is the deal with C6? Seems like it would be dumping treble to ground before...

Ooohh. The XLR mounted one sounds perfect. I have use the AMZFX multipurpose opamp board for this in the past but had to modify it to remove the gain he designed into it and added a voltage divider to the input because the output was still too hot.

No build documents available yet so I’m wondering if this will be capable of using the inverted and non-inverted outputs simultaneously for use as an active direct box. ?? Doesn’t seem like there are quite enough components on the board to do this the way I am familiar with...

Been quite a while and couldn’t remember what I did so I had to crack it open and get a pic. I did standard diodes on the low gain side and on the high gain side I used germanium hard clipping and asymmetrical combo for soft clipping. Then I squeezed in an external switch to select between...

Yes there are lots of Marshall flavored pedals designed to make your amp sound similar to a Marshall, but few preamps to use in conjunction with a cab sim to take the place of an amp.

I have built the Cobbler preamp and use it as a clean pedal platform along with the Unicab to run direct to FOH and it works great. I recently bought the Bobby preamp board planning to build a Marshall flavor to use as well. After reading some reviews of the Sheriff that it is derived from, I...

A very good suggestion. Alternatively, I could put in a separate voltage multiplier for the Unicab and DI and just use the separate 9v supply.

I have built this amp sim box out of a Cobbler, Unicab, and an AMZ opamp board for an active DI output. https://forum.pedalpcb.com/threads/amp-cab-di-experiment.16398/ I want to run it from a spare 18v output on my power supply instead of a separate 9v power supply for better headroom on the...

Turns out the unpleasant distortion I was hearing was not from the Cobbler after all. The output of the DI was too hot causing clipping in my recording interface even with the input gain all the way down. I had to rework the DI circuit remove the gain from. Took it to band practice instead of my...