ALM-003 ‘SID GUTS’ - Operation Manual -
Introduction ...........................................................................................3 Features ...............................................................................................................4 Technical Specifications .......................................................................................5 Caveats.................................................................................................................5 Core Operation.................................
ALM-003 - ‘SID GUTS’ Introduction The MOS Technology 6581/8580 'Sound Interface Device' chip1, aka the ‘SID’, was the sound generator chip used in the Commodore 64 home computer - the greatest selling home computer of all time. The SID, by the means of 3 wavetable oscillators, a real analogue multi mode filter, an ADSR and various cross modulation options, provided the soundtrack to a generations gaming and perhaps many peoples first exposure to real sound synthesis.
ALM-003 - ‘SID GUTS’ Features The SID GUTS supports to following SID chip features via modular control; • 1volt per octave control of a ‘core’ SID oscillator 0-5v input (with tunable offset) • Direct and voltage control of oscillator wave shape selection (Pulse, Triangle, Square, Saw) • Filter switchable between 4 modes - 12dB/Octave HP , LP , BP & Notch (HP+LP) • Direct and Voltage control (with offset) of Filter cutoff and Resonance.
ALM-003 - ‘SID GUTS’ Technical Specifications • Supply: +/-12V • Current Draw: ~50-200ma (up to 200ma with 6581/8580 SID chip installed) • Size: 12 HP • Depth: 30-40 mm (with heat sinks installed) Caveats A SID chip is vintage technology! As such there are a number of limitations; • A real SID chip is noisy. • Filter performance varies between chips. • Resonance has very little effect and sometimes even unexpected. • SID chip updates are limited to approx. 50Hz thus very fast (i.
ALM-003 - ‘SID GUTS’ Core Operation Panel Layout LP BP HP Pulse wave shape pulse width control. PWM Filter Cut off control. FILTER PWM Pulse width CV attenuator. Wave Shape Filter type selection. _ Filter Pulse width CV input. 0-8V Res Mod Osc Sy nc M od Filter cut off attenuator. Filter resonance offset & attenuator. Modulation oscillator type selection control. Shape Type V/Oct Filter Resonance CV input. 0-5V Modulation oscillator 1 volt per octave input.
ALM-003 - ‘SID GUTS’ Overview The SID GUTS panel provides both direct user and interfaced voltage control of the various SID chip audio parameters. The SID GUT’s can be best thought of as a core wave table based oscillator with a built in multi mode filter and a second cross modulation oscillator. This provides classic SID type sounds but with modular levels of control. Synthesized audio is output through the 'output' jack. The external input allows external audio to be passed through the filter.
ALM-003 - ‘SID GUTS’ Filter Section The SID provides a multimode filter which acts on both its internal oscillator and any external audio signal. The filter mode can be switched cycled between low pass, band pass, high pass and notch (low pass & high pass combined) by pressing the blue filter button. The associated LED's will light indicating the mode. The cut off point of the filter is controlled by the large filter control knob.
ALM-003 - ‘SID GUTS’ Modulation Oscillator section This section provides access to a second onboard SID oscillator which can be used to modulate the main oscillator in interesting ways. The frequency of the modulation oscillator is controlled by the 1 volt per octave input (0-5V range). Modulation type is controlled by both the voltage control input (0-5V) and via cycling through type with the push button. The modulation types are None, Sync and Ring Modulation.
ALM-003 - ‘SID GUTS’ Limited Warranty From the date of manufacture this device is guaranteed for a period of 2 years against any manufacturing or material defects. Any such defects will be repaired or replaced at the discretion of ALM. This does not apply to; • Physical damage arising for mistreating (i,e dropping, submerging etc). • Damage caused by incorrect power connections. • Overexposure to heat or direct sunlight. • Damage caused by inappropriate mis-use.
ALM-003 - ‘SID GUTS’ Support For the latest news, additional info, downloads and firmware updates please visit the ALM website at http://busycircuits.com and follow @busycircuits on twitter. Please send any questions or comments to info@busycircuits.
ALM-003 - ‘SID GUTS’ APPENDIX I: Technical Info Connection of SID chip The SID GUTS uses a real 'SID' chip connected to the DIL IC socket on the rear of the SID module. Together with the IC socket, there is a jumper for setting the type of SID chip used and also two sockets for 5mm filter capacitors.
ALM-003 - ‘SID GUTS’ The SID GUTS supports 3 different types of SID chip; The original 6581 chip, the later 8580 and a modern hardware emulation chip - the 'SwinSID'. The SID chip should be clearly identified. Beware of fake SID chips or patly working SID chips with broken filters. • For a 6581 chip, the jumper should be set accordingly for 12V. The capacitors should be 470PF (supplied). • For a 8580 chip, the jumper should set accordingly for 9V, the capacitors should be 22NF.
ALM-003 - ‘SID GUTS’ IMPORTANT INFO. READ! Vintage SID chips are a very old technology and known to run hot and pull a lot of current. If you decide to use a vintage SID chip (instead of a modern ‘SwinSID’ chip) with the SID GUTS; • Make sure your power supply has adequate power available (~200 milliamps). • Make sure your case has plenty of space around the module to allow air flow and/ or good ventilation. • The supplied heat sinks should be attached to the two regulators on the rear of the module.
