JH Tau Pipe Phaser Built As Pedal - Build Report!

[Strategy]

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.

- Strategy

[Brymus]

Nice !!
I really like the way that looks,its very DIY but mysterious and minimal,could be anything.Makes you wanna step on the switch to see what happens...

[StephenGiles]

JH is in the process of designing a new vocoder at the moment.

[frequencycentral]

A real worthy project to take on. I'm jealous as hell. You should be suitably proud of yourself!

[Strategy]

I never label my stuff- there is a similar aesthetic developing between them. I always remember what the knobs do, but I have trouble remembering which jacks are input and output (!) so I've started to mark those with one of those clear round bumpon feet you get at smallbear, just next to or above the input so I when I'm plugging things in I can feel the plastic dot and remember.

One of these days I'll learn decalling. Why does it seem so scary??

- Strategy

Nice !!
I really like the way that looks,its very DIY but mysterious and minimal,could be anything.Makes you wanna step on the switch to see what happens...

[Strategy]

I've been following that vocoder project. Not sure I'll realistically ever get to it: I hope to do his flanger project and forthcoming BBD delay project. I estimate that right there is a couple years' worth of work.

One project that I've heard in person that just sounds great and would make an ideal standalone pedal is the Polymoog fixed filter bank:
http://www.jhaible.de/resonator/resonator.html
CV inputs, envelope follower, or LFO could be easily modified and the pcb includes mod/experiment blank pad grid. The module sounds great on its own though for like extreme EQ type effects.

JH is in the process of designing a new vocoder at the moment.

[Strategy]

cheers thanks! feels great to  be back in my pedal building projects

A real worthy project to take on. I'm jealous as hell. You should be suitably proud of yourself!

[Taylor]

Do you have any clips? I know Juergen has some, but I'd be interested to hear this with something other than synths. (Don't remember whether you play guitar at all.)

[Strategy]

I play, er, make sound with, guitar, among other things. i'm going to do some comprehensive sound clips tonite!

Do you have any clips? I know Juergen has some, but I'd be interested to hear this with something other than synths. (Don't remember whether you play guitar at all.)

[Taylor]

Cool. I like synths, but I think it's cheating to use synths to show off effects. An effect is more impressive when it can make the most boring sound ever (clean guitar) sound interesting.  How's the WTPA going?

[Rectangular]

Cool. I like synths, but I think it's cheating to use synths to show off effects. An effect is more impressive when it can make the most boring sound ever (clean guitar) sound interesting.  How's the WTPA going?

I don't distinguish between synth modules and effects pedals anymore. in the case Lovetone, Moogerfoogers, and some EH offerings, they are literally one and the same.

The guy at my post office is a jerk, so I've been building with 100% local parts for the past year or so (challenging !).. I kind of miss ordering PCBs and stuff from DIY places like electromusic.

can't wait to hear some clips

[Strategy]

Cool. I like synths, but I think it's cheating to use synths to show off effects. An effect is more impressive when it can make the most boring sound ever (clean guitar) sound interesting.  How's the WTPA going?

Hey Taylor, I don't know if it's cheating to use synth to show off effects, but it is ineffective just because its hard to know what's the effect and what's not. I did a guitar demo here- sorry its un-elegant, it is very off the cuff just to give a sense of the thing. The noise floor is from my mixer. I play a beat up Hohner Steinberger copy into a beat up Seck mixer, with a tad of Joemeek MC2 compression:

http://www.cascadianknights.org/share/strategy/Tau%20Test%20-%20Strategy.mp3

First there's stereo phasing at various modulation depths...then stereo phasing step-sequenced by a Frostwave analogue sequencer...then there is some mono phasing with step sequencer AND LFO at the same time.

I will also put up a sound sample with a Farfisa organ drone, with some uneffected organ for comparison. The reedy, raw sound of the organ is VERY dramatically cut by this particular phaser so you can really hear the details of the 20 delicious phasing stages.

BTW, "where's the party at" sampler project is now trouble shot (I think), but I don't yet have an enclosure selected. I have a Red Llama and an Experience to finish as well.

- Strategy

[Strategy]

I don't distinguish between synth modules and effects pedals anymore. in the case Lovetone, Moogerfoogers, and some EH offerings, they are literally one and the same.

The guy at my post office is a jerk, so I've been building with 100% local parts for the past year or so (challenging !).. I kind of miss ordering PCBs and stuff from DIY places like electromusic.

can't wait to hear some clips

The one thing that keeps me from really seeing stompboxes and synth modules as equal is form factor and levels. really running line level into most synth modules without amplification to step up to 10v will leave your signal hissy and yucky. There is a synth DIY pcb called "stompbox adaptor" from cgs.synth.net (uuhhh.I think that's the link) that allows you to adapt both power and signal levels such that a typical synth module can be used as a pedal. Fortunately there are some fun 9v VCF's and things, but you can see where such an adaptor would come in handy. There is also a pcb to do the reverse so that you can effectively use stompboxes with your modular system.

- Strategy

[Brymus]

I really like the stereo sound in that clip,very noticeable stereo.
That phaser sounds great ,would be nice for doing some old Cure or Bauhaus covers.
Is the PCB home etchable or does it require purchasing from the designer ?

[Taylor]

Ooh, that sounds really cool. It's pretty close on the strangeness scale to my Lovetone ? Flanger I built, but with some pretty interesting sounds I haven't seen in a flanger before. I'll be interested in hearing the Farfisa drone; I'm working on a DIY CMOS organ right now specifically to get some Farfisa-ish drone sounds happening.

BTW, I was just kidding about it being "cheating" to use synths. I just mean, as you say, that it's hard to tell what specifically the effect is doing when the source material is already more complex than a guitar. I actually don't even play guitar myself.

[Strategy]

@ Taylor: The CMOS organ sounds cool!

The ? Flanger would be awesome to build...maybe one day that project will get revisited/revised in the forum, as the info about it is kinda spotty...This pedal definitely does some bizarre stuff, I did a show the week before last with my sampler run through this and hard panned stereo phasing...it was a medium room with a low ceiling DIY club space and the effect was really 3-D.

[Strategy]

I really like the stereo sound in that clip,very noticeable stereo.
That phaser sounds great ,would be nice for doing some old Cure or Bauhaus covers.
Is the PCB home etchable or does it require purchasing from the designer ?

Yeah I really thought of early Cure when I first plugged this in with guitar.

the pcb is not home etchable. these are very complex 2-sided boards. you have to order it from the guy, and actually, this pcb is out of stock with him but his US supplier has them, www.thebridechamber.com. They have parts kits too. You get what you pay for with JH pcb's though, fantastic stuff.

- Strategy

[Taylor]

@ Taylor: The CMOS organ sounds cool!

The ? Flanger would be awesome to build...maybe one day that project will get revisited/revised in the forum, as the info about it is kinda spotty...This pedal definitely does some bizarre stuff, I did a show the week before last with my sampler run through this and hard panned stereo phasing...it was a medium room with a low ceiling DIY club space and the effect was really 3-D.

Yeah. I don't have time to trace it myself but I'm sending my ? clone to somebody for them to trace it out. Then we'll have actual schematics and wiring diagrams instead of perplexing photos only. That will make the build much more manageable.

[Strategy]

Yeah. I don't have time to trace it myself but I'm sending my ? clone to somebody for them to trace it out. Then we'll have actual schematics and wiring diagrams instead of perplexing photos only. That will make the build much more manageable.

well, I will be really stoked on that. Will keep my eye out!

[Rectangular]

Yeah. I don't have time to trace it myself but I'm sending my ? clone to somebody for them to trace it out. Then we'll have actual schematics and wiring diagrams instead of perplexing photos only. That will make the build much more manageable.

well, I will be really stoked on that. Will keep my eye out!

Taylor: how did you manage to make a "?Flanger" without having any kind of schematics, parts list, or pcbs ? Or is my understanding that you didn't construct it youself, and someone else out there has been cloning these ? I've cloned the entire lovetone family except the doppleganger, wobbulator, and ?Flanger.  the doppleganger and wobbulator aren't really interesting to me as I have enough other equipment that will emulate all of their functions... but the ?Flanger is pretty unique, and I've been wanted to build one for years. please keep us updated