> it's not a simple 3rd-order low pass.
I don't think it is 3rd-order anywhere.
Confirmation: the steepest slope is ~~10dB/oct or 1.5-order, and most slopes are simply asymptotic to 6dB/oct or first-order.
I see it as two channels.
The treble is low-cut twice; except that first low-cut is "spoiled" by the large pot resistance unless you are at the extremes.
The bass is high-cut twice; except that first high-cut is variable-frequency due to the large pot resistance off the extremes.
You would naively expect simple flat, high-shelf, low-shelf.
However with multiple R-C networks you get enough phase-shift that simple addition of amplitudes does not give the right answer. The "overlap" zone could add, but in fact in this case it cancels. Hence the deep dip at some settings. This is a recurring theme in guitar amps: the classic Fender stack does it at some settings, and Gibson sprinkled twin-Tee filters liberally.
The "10dB/oct" happens only on the edge of this dip. It is possible there is a setting which gives "infinite" dip, and infinite dB/oct over an infinitely narrow band. But I think the steepest slope you will "hear" is a 200Hz fundamental suppressed 28dB, its 4th harmonic down only 7dB, a >20dB boost of the 4th harmonic, which will sound like "all harmonic no fundamental". Which is not a natural guitar sound (unless you damp a node on the string) but is standard among the conical bore wind instruments.
I think it generally covers the same ground as the Fender, with a few more parts, but more same-value parts, which could be cheaper in small production (if you build 5,000, then one 10,000-crate of 0.0047u is cheaper than two 5,000-crates of two different values).
Topic: Traynor YGM-3 Mods (Read 22502 times)