Hi Paul, thank you. You know, you sold me instantly on your speaker design when I first read about it. I had by then concluded that an OB speaker must be the ideal, a box being a compromise one would better do without. FR drivers are coherent. And multiple drivers reduce distortion, and move air. I can't think of anything better than an array of FR drivers in OB. It then occurred to me your power supplies must be quite something if your audio preferences go the direction of the speaker you built for yourself. That's when I started using your supplies.
IIRC, the field coil current draw per driver is nominally 1A, with a voltage range of 6-17VDC thereabouts. I'll get confirmation of those figures.
I'll take your advice and drive the drivers in parallel. My amp (being constructed) is a SIT amp with two SIT devices on the output operating in class A. The amp will operate in what I prefer to call parallel SE, as the SIT devices will operate in reverse phase to each other, but drive separate drivers. Each SIT will thus drive two drivers in the above array. Given the SITs' reverse-phase output, they will be connected inversely at the drivers to allow power supply noise cancellation at the drivers' summed acoustic output. That be the theory so far. We'll see if it works!
The load presented to each SIT will be 16/2 = 8 ohms nominal, which is an acceptable impedance for the SIT devices (I'll have SIT operating voltage soon for the shunts I asked you to design).
DAC is a TotalDac with four channel output operating in differential stereo. I haven't figured out the coupling yet between DAC and amp. I have Feastrex Finemet transformers I'll use if I can swing a proper design for biasing the SITs, as their use would allow some bias-supply noise cancellation if the SITs are biased via the centre-tap of the transformer with the same supply. The only problem here is that each SIT requires a different bias voltage, though that could be accomplished through separate resistor dividers. Volume control will be digital, for starters (in the DAC). If that doesn't work well, I'll figure out some Lightspeed arrangement.
