Back in the DIY game after some several month detours due to real life, work life, personal life, playing-in-bands-that-are-busy life...It's nice to be back. This is a preliminary post with pics- audio to come tomorrow.
I have been working on this project for about a year and a half off and on, chipping away at it. It is the JH Tau "The Pipe" Phaser. Link to JH's project page: http://www.jhaible.de/tau/jh_tau.html
. A pcb project issued by synth-DIY guru, Juergen Haible who is occasionally in this forum but mostly active on www.electro-music.com
and the synth-diy mailing list. Juergen loves rack mount gear and many of his projects make fantastic standalones, with onboard power supplies. I thought, why not make it a floor/keyboard-top/desk-top module, equally at home on my mixing desk or on the floor? Like a moogerfooger, lovetone, etc. ...My favorite projects are flexible, and patchable with CV's, but you can simply rock on them too.
His pcb's are flawless, transparent design - however, the config. of controls is largely left to the builder- I found this "choose your own adventure" aspect difficult as I am a pretty paint by numbers DIYer. The pcb is also configured to accept several different chipsets for the phasing; I got the highest end chipset, with SSM2210's. The pcb is currently out of print but the US modular synth hobby shop The Bridechamber (www.thebridechamber.com
) still has some, I think.
This project is a phaser that is almost flange sounding because at the deepest modulation settings you get a little pitch bend. It does everything from subtle, univibe like effects to over the top, cutting filter type "sounds like your head is in a pipe" (hence the name?) effects. Mine has stereo outputs (1 main + 1 aux) for 3-D effects, single input, LFO CV output, frequency CV input, 1V/octave "tuned" CV input, a switch to go between "phasing" (deep) and "vibrato" (light modulation), and potentiometers to control LFO depth (goes all the way to zero for manual phasing), LFO speed, frequency, level. The two LEDs indicate LFO rise and fall, going back and forth. There is also a switch for LFO wave shape (ramp/saw).
Here is one of my ferrets Mishka beta testing the pedal.
I am nervous to show gut shots because my guts are generally way less awesome than all the super tidy gut shots you see in the pics thread. This gives you a sense of the complexity. Refer to the JH link above for a diagrammatic view of the pcb. Sorry I could not get a better shot after I got it all assembled, without completely removing my panel components.
The enclosure is a repurposed phone equipment switch box that I got at a local nonprofit called Free Geek. Free Geek recycles electronics and computer equipment; if you log enough volunteer hours for them doing recycling labor you get a revamped Linux box and training in how to use it. Their programs serve Portland businesses with a computer disposal resource and 1000's of low income residents with home computers. Their thrift store is a treasure trove of useable enclosures for my music proj's.
Stuff I learned:
- Transformers and mains power are scary to me. They also make pedals heavy. I had a friend who is a seasoned DIYer and electronics technician help me do this part. I owe this friend a huge favor for helping me trouble shoot and wire the power.
- Troubleshooting a project this big is hard. Issues included wrongly wired audio ins and outs, not being able to figure out the 4PDT stomp, and a bent IC leg that we finally caught. With 20 phasing stages that's a lot of IC's to mess up...
- Synth modules make good pedals if you are up for the effort and the JH projects lend themselves to this concept. Other modules would require a lot of power supply work to deal w/ bipolar 15V, and level conversion for the signals.
- It was worth the wait and slow work.
lastly, I love phasing and I can't wait to do more. Mutron Biphase, perhaps?
I hope you enjoyed this off the beaten track project report questions are welcome/comments and I will post audio too.