Circuit Atlas · HUSH M4 · Rev 2027.4 draft
S3a Isolator building block
Schematic for S3a Isolator building block. Design targets and calculations, no measurements.
IN DEVELOPMENT · REV 2027.4 (DRAFT) · DESIGN TARGETS, NOT MEASUREMENTS
HUSH M4 is in development. This draft is published on zakkhutoretsky.com; it has no price and no ordering. Figures marked design target are goals for the finished product. Figures marked calculated come from the published formulas. No value on these pages was measured on a built unit. Interviews are cited as the design brief, not as an endorsement.
See this control Master isolator on the playable panel
S3a Isolator building block
| Item | Value / formula |
|---|---|
| Section | Second-order Butterworth Sallen-Key, equal resistors and equal capacitors, f0 = 1/(2πRC), K = 1 + Rf/Rg = 3 − 1/QR3 |
| LR4 | Two cascaded sections give a Linkwitz-Riley 24 dB/oct filter, each stage Q = 0.71R4 |
| Values | C = 10 nF. 300 Hz: R = 53.6k (f0 = 296.9 Hz). 3 kHz: R = 5.36k (f0 = 2969 Hz). Rg = 10k, Rf = 5.9k gives K = 1.59, Q = 0.709 |