TipTop Audio has realized a completely Eurorack-compatible version of the Frequency Shifter 285 in cooperation with Buchla. The 285t has two independent functional areas. If you have a soft spot for ring modulation, metallic sounds, atonal frequency manipulation and extreme sound changes, you should take a closer look at the 285t.

The upper half of the module is an analogue frequency shifter. Even though this function specializes in changing frequencies, it has nothing in common with a pitch shifter. The Frequency shifter shifts all frequencies of the incoming audio signal to the same frequency. For example, if the shift frequency is 200 Hz, 1000 Hz becomes 1200 Hz, 2000 Hz becomes 2200 Hz and so on. The frequency range of the internal reference oscillator is 1000 Hz, which can be replaced by any external signal. The DIFFERENCE output provides the signal with the difference between the main signal (e.g. 5300Hz) and the reference oscillator (e.g. 800Hz; i.e. 4500Hz). The SUM output is a simple Mix from the main signal and the reference signal.

The lower half of the module is an analogue balanced modulator, which most people will be familiar with as a ring modulator. A ring modulator determines the sum and difference of two signals simultaneously and superimposes them on top of each other. This works best with waveforms with low overtones such as sine and triangle. Of course, other waveforms and wavetables also work, so experimentation is highly recommended. The RING output is a classic 2-quadrant ring modulator. The VARIABLE output can be adjusted manually and via control voltage from no ring modulation (zero) to 100% ring modulation (ring).