Pro Audio Design Forum

So far I've used identical C values per pole with them cascaded in series. The phase delay per section is the same and adds. It seems to sound better - deeper to me at least - than when the values are mixed. (During test I tried this.) Most of the phaser cites I see use identical values though it's ...

I've tried values between 220 pF and 47 nF depending on the topology. 220 pF seems to offer the widest range using only VCA attenuation in the Hoshuyama topology. I determined this by looking at an FFT of the notch on white noise. Really large values, say 47 nF, compress most of the range in the sub...

OK, I've been playing with this for a few days and the Hoshuyama topology is the way to go. Sam Hoshuyama was very kind to allow me to modify and use his SSM2164-based circuit. With the help of Gary Hebert of THAT to transform it to a non-inverting VCA, I was able to protoboard a 4 pole phaser. I'll...

This may be an earlier citation for an SSM2164 based phaser from Osamu Hoshuyama. It's dated before Neil's Webbly World phaser. http://userdisk.webry.biglobe.ne.jp/000/024/65/1/Vcph0505.GIF With some help from someone more skilled than I, I was able to modify the Hoshuyama circuit to use a THAT2180....

Yep, the Vos of an untrimmed 5534, though not a lot, at 6 mV/dB can provide significant tracking error in Ec.

Point taken on the Vos error. There will have to be a trim anyway to set the maximum gain limit to slightly less than unity. Right now the VCAs have a common Ec bus. If any of them go into gain, positive feedback results. I'm using a pre-bias of 3 mV, about -0.5dB, to keep that from happening. (The ...

I took a little break from working at the O.K. Ranch to test out a few phaser ideas. With brush set-out about another week away the chainsaw and I are enjoying a little separation. I do miss the smell of 2 cycle fuel though. Bifet op amps for the VCA input buffer and the all-pass sections is a defin...

Probably want to settle on 0-5V and +/-5V sweep inputs then. Makes envelope control easy. Could have a single input with bypassable level shifter to switch between unipolar and bipolar sweep. Exactly my thought Roger. Thanks emrr for the feedback on the samples. I was concerned that phasing may hav...

I was thinking about keyed effects based on dynamics and some crude form of frequency tracking in addition to an LFO. I'd like it to mutate a high hat by being keyed from it or follow a guitar part kinda-sorta. (Which I did by knob turning.) Pedal operation for sure. Stuff that made the DynaFlanger ...

yes gain cell is non inverting, looks like voltage input, not current input. I think it's current in. http://www.analog.com/static/imported-files/data_sheets/SSM2164.pdf The 30K is the input V-I converter. The 30K wrapped around from the output back to the 2164 input alters the gain control slope (...