Pro Audio Design Forum

It's 20 uH 22 Ohm min or 25K max and yes its 1.6 kHz but as I point out the Q is nada at both extremes. It introduces a nice HF gain rolloff. Joe Neil in Waynes mic pre used them IIRC at max gain the 3 dB point we used was around 80 kHz. I would have split the two inductors and placed each at their ...

Here are some tone burst oscillograms comparing ripple without and with the quadrature channel summed in. It's a few cycles of 50 Hz with a Ct of 2.2 µF and an It of 7.5 µA for a log-domain tau of 7.6 ms. Default dBx timing is around 35 ms so this is an example of the fast-response low ripple capabi...

Q = 0.009 with VR1 at 0Ω.
Q = 8.25E-6 at 25KΩ.

I've put inductors in Rg to rolloff RFI.

Interesting but is side chain signal rectification the significant audible concern in side chains? https://groupdiy.com/threads/that2180-vca-based-compressor-90deg-detector-filter.81970/ https://groupdiy.com/threads/some-ideas-for-compressor-side-chains.52305/#post-666719 I thought I recalled Jakob...

Detector ripple produces odd-order distortion which is very audible when it's down in the power portion of the waveform. The Waveulator has shown us you can murder the peaks symmetrically with clipping but not the power portion of the waveform which is far more "delicate." When I get it co...

The sidechain schematic is a work-in-progress. The prototype will use the audio path of a Waveulator and a Quadrature Summing Filter board. https://proaudiodesignforum.com/images/jpg/Unocomp_Sidechain_Schematic_040824.jpg (Schematic updated 4/8/24.) I'm using an old school dBx 303 type RMS detector ...

It might seem sin² + cos² is overly complex when a stereo detector is required. By following Blackmer two 90° Dome networks and four log detectors would be needed. Fortunately that is not the case due to the unique property of the 90° Dome filter to equally weight L+R and L-R inputs. By splitting th...

Thanks John. I forget the oscillator manufacturer that uses sin/cos zero cross to sample the opposite. E.g. zero cross of sine drives a sample and hold which captures the peak of cosine and vice-versa. The beauty of this approach is that we already have the squared term in the log domain when the de...

A Quadrature Power-Summed Compressor Sidechain Inspired by Blackmer's figure 4 in his RMS detector patent I'm working on a stereo compressor sidechain that uses a sin/cos Dome filter along with "True" Power Summing. I call the sidechain topology "Quadrature Power Summation" due ...

"Performance Limits In Contemporary Console Design," John Roberts, Recording, April 1980.

https://proaudiodesignforum.com/images/ ... 980-04.pdf