How-To Speed Mod a Tape Player

Demonstrating a speed input mod I added to this FiiO CP13 Cassette Player. This mod adds an 3.5mm tape speed input jack to the FiiO CP13. When nothing is plugged in the speed is set by an internal trimpot (the input jack is switching). When a 3.5mm mono cable is plugged in, the internal trimpot is switched out of circuit and the speed is determined by the resistance between the two leads of the audio cable. In this performance the resistance, and therefore the speed, is being controller by a photoresistor (LDR) illuminated by an LED (a combination called a vactrol). The LED power of the vactrol is being set using the CV (Control Voltage) output of a Korg SQ-1 Step Sequencer. In this way, the speed of the FiiO CP13 tape playback, and as a result, the pitch, is sequenced. The speed input could also be controlled by a potentiometer, touch sensor, or any number of other resistive components. FiiO CP13 Cassette Player - https://amzn.to/4cyMz5H Korg SQ-1 Step Sequencer - https://amzn.to/42unqDf VTL5C3 Vactrol - https://amzn.to/4cXahHH 3.5mm Switched Jack - https://amzn.to/4w8k4U0 Trimpots - https://amzn.to/4utJYjG Resistors - https://amzn.to/4tPwtuM Speed Input Parts -- 1x 1kΩ Trimpot (Trimmer Potentiometer) 1x 3.5mm Switched Jack CV-Resistance Parts -- 1x VTL5C3 Vactrol 1x 330Ω Resistor 2x 3.5mm Jack The CP13 employs the renowned JRC5532, known to some as the classic "King of op-amps." This op-amp is deployed in a fully analog audio circuit that provides a familiar, pleasant sound that will surely leave an impression. ------------------------------------------------------------------------------------ substatica Discord -   / discord   ------------------------------------------------------------------------------------ 00:00 - Intro 00:58 - Demo 03:42 - Vactrol-to-resistance box overview 04:40 - FiiO CP13 teardown 06:14 - Mod overview 09:06 - Reassembly ------------------------------------------------------------------------------------ Buy Me a Coffee - https://www.buymeacoffee.com/substatica One Time Donation - https://streamlabs.com/substatica/tip PayPal - https://paypal.me/substatica Merch - http://store.substatica.com ------------------------------------------------------------------------------------ #fiio #fiiocp13 #korgsq1 #speedmod #synth #jam #chill #ambient #cinematic