jeffwhitfield
Well-known member
Finally finished this sucker today! Took a while with this one. Had a debacle over some REVV builds and ended up with some store credits on the PCB Guitar Mania site. I had already built an Obsidius Preamp but really wanted something closer to a Darkglass Microtubes B7K. Picked up a Black Mirror VII board and waited for it to arrive, which was in October. Once I got it, I started planning the build but held off on ordering parts due to an announcement of a few mods that add a couple of settings from the B7K Ultra.
Finally got around to building it a few weeks ago. Build went pretty smooth. After getting the main stuff on the board, I plugged it in to test it out. Everything worked for the most part....but the Drive was acting funny. Distortion worked only for the first 30-40% of the pot. Dropped out after that. Replaced the op-amps, which helped and got it to where it wouldn't start dropping out until 80-90%. Played with the op-amps and I think one of the sockets was being finicky. Once I made sure everything was seated well seems the Drive pot started to work better.
Last thing is the Ultra mod that adds a few switches for the selection of Hi-Mids and Lo-Mids frequencies. I opted for the 168 Hz (100n) and 500 Hz (10n) options for the Lo-Mids and 1.55 kHz (3300pf) and 3.3 kHz (680pf) for the Hi-Mids. This is about as close as I felt I could get to the original B7K options. Mods worked well and do add quite a bit of flexibility. Might play with different caps later on with a custom breadboard or something. Still damn good as-is though.
Once I put everything together, I noticed that I messed up the enclosure design a bit. Seems I got the Grunt and Ultra-Hi switch labels mixed up. Didn't have any labels set for the mods so I just added a label there too. This is my own personal pedal so no biggie. Not anything I plan on selling so no harm, no foul.
Sound-wise, this ended up being a really, really great pedal for me. I bought a Darkglass Vintage Deluxe v3 to compare it to. I'm very surprised at just how close the Black Mirror is to it. Granted, the options aren't quite the same but still very comparable and highly flexible. The drive character is different with the Vintage. Like many reviewers have said, it's warmer than the B7K...which is certainly the case with the Black Mirror. I was surprised that I ended up liking the Black Mirror more though. The drive has a richness about it that the Vintage doesn't have. Just feels like I can get it to cut through a mix easier. Definitely more modern sounding...but with a few tweaks it can get quite mellow and warm. Maybe not quite like the Vintage...but close enough.
Overall, I'm very happy with this preamp. I'll be returning the Vintage and sticking with the Black Mirror as my bass preamp of choice.
Finally got around to building it a few weeks ago. Build went pretty smooth. After getting the main stuff on the board, I plugged it in to test it out. Everything worked for the most part....but the Drive was acting funny. Distortion worked only for the first 30-40% of the pot. Dropped out after that. Replaced the op-amps, which helped and got it to where it wouldn't start dropping out until 80-90%. Played with the op-amps and I think one of the sockets was being finicky. Once I made sure everything was seated well seems the Drive pot started to work better.
Last thing is the Ultra mod that adds a few switches for the selection of Hi-Mids and Lo-Mids frequencies. I opted for the 168 Hz (100n) and 500 Hz (10n) options for the Lo-Mids and 1.55 kHz (3300pf) and 3.3 kHz (680pf) for the Hi-Mids. This is about as close as I felt I could get to the original B7K options. Mods worked well and do add quite a bit of flexibility. Might play with different caps later on with a custom breadboard or something. Still damn good as-is though.
Once I put everything together, I noticed that I messed up the enclosure design a bit. Seems I got the Grunt and Ultra-Hi switch labels mixed up. Didn't have any labels set for the mods so I just added a label there too. This is my own personal pedal so no biggie. Not anything I plan on selling so no harm, no foul.
Sound-wise, this ended up being a really, really great pedal for me. I bought a Darkglass Vintage Deluxe v3 to compare it to. I'm very surprised at just how close the Black Mirror is to it. Granted, the options aren't quite the same but still very comparable and highly flexible. The drive character is different with the Vintage. Like many reviewers have said, it's warmer than the B7K...which is certainly the case with the Black Mirror. I was surprised that I ended up liking the Black Mirror more though. The drive has a richness about it that the Vintage doesn't have. Just feels like I can get it to cut through a mix easier. Definitely more modern sounding...but with a few tweaks it can get quite mellow and warm. Maybe not quite like the Vintage...but close enough.
Overall, I'm very happy with this preamp. I'll be returning the Vintage and sticking with the Black Mirror as my bass preamp of choice.