Pittsburgh Modular – Taiga Pics & Points

Some pics of the Taiga. And some observations…

Taiga does wave shaped FM melancholy sounds…

Right, this started off through means of curiosity simply rather than a serious wish to modify a lot of aspects of this synthesizer. The Taiga is great and I like most of it very well, except maybe how the envelopes are very long and some modulation intensities are rather strong on very short amounts of knob travel.

Anyhow, someone suggest to simply email Pittsburgh and while I usually don’t ask for info about mods I though hey, good opportunity to say hi. Turns out, Richard, the company owner himself, answers after a couple of hours and is super friendly and passes on some good hints I’ll share below – how about that? Nor I kind of feel compelled to mod more…

Pictures

Some pictures first for orientation… Proper descriptions will follow and mod info is below. Front panel off…

Mind the ziff connectors!

Taiga flipped open…

Oscillator saw core, I reckon (op-amp, comparator and transistor setup)

Part of the expo converter/pitch stabilisation circuitry SSI2164 + trimmer

Wave shaper (i.e. wave forms derived from saw core) section: classic opa-diode stuff

LM13700 OTAs (3 OTA cells used, it appears, so I think that’s for the wave-folder circuitry

CPU and some ground connections that wanna get dirty (or already are)

Coolaudio V571M compander for the delay

speaking of the delay… bob’s me cheeky chap – best lofi BBD (Erica and Neutron approve)

more soon & will try to document some little changes as soon as I have more time on my hands…

Some modifications

Richard passed on some valuable hints for anyone interested in changing stuff in their Taiga:

ADSR 1 Timing Cap E6 4uF7

ADSR 2 Timing Cap E7 4uF7

Dynamics Timing Cap C113 1uF

Preamp Gain R159 30K

Max Delay Time R102 30K (panel PCB)

LFO Range C144 22nF (panel PCB)

LFO Range Long C143 2uF2 (panel PCB)

Words of warning about the electrolytic caps that handle general envelope speed. These capacitors are soldered onto the PCB in a way that the terminals are for the largest part UNDERNEATH the component itself. The PCB terminals are fickle and can tear off ver easily – this is not Pittsburgh’s design but simply how SMD electrolytic caps in this form factor are done. If you have no experience in desoldering stuff like this, best test somewhere else first or have it done by someone w skills/tools.

Still testing stuff on my unit but I guess I will settle for 2.2uf but will also modify my decay knobs a bit. these potentiometers are 1M with the wiper and pin1 connected, i.e. they work as variable resistors. I’ll test wiring a 1m resistor across wiper and Pin3, so that the maximum decay time is halved and the pot range shifted accordingly —> more room for sweet snappy spots in teh first third of the knob. I’ll post updates when i get to it.

Sorry for the hobbled text – more time soon… 🙂