100m-ish Audio Delay
This 8HP Eurorack module emulates the Audio Delay function of the Roland-100m M-172 module.
The circuit has been modified to operate with Eurorack power supplies and signal levels, and to address other issues with the original circuit.
As the MN3004 BBD chip used in the original circuit is now rare, the PCB is designed to accommodate either an MN3004, or the much easier to obtain MN3007. It has also been tested and works with MN3207.
The PCB in theory also supports various other MN30XX and MN32xx series BBD chips though not all of these options have been tested so far.
The original specs for the Roland module are:
- Delay 0-7mS
- 30Hz – 20 KHz
- S/N 60dB
- Input: 10V 50K
- Output: 1K
- External CV: 10V max 50K
- The module includes the original LFO circuit, where the output amplitude decreases with increased LFO rate:- LFO range 0.04 Hz to 10Hz- Amplitude:o 10v p-p at 0.04Hzo 400mV p-p at 10Hz
- PCB: GBP 10.00 (in stock)
- Panel: GBP 15.00 (in stock)
This LFO is intended to replicate the user interface and most of the behaviours of the
Roland 100m LFO (as found in the M-140 and M150 modules).However, the internal circuitry is totally different to the Roland – it’s PIC based, using code derived from the Electric Druid VCLFO9D (used with permission).
- The module also has a "hidden" sample and hold waveform option.
- PIC code Link
- PCB: GBP 8.00 (in stock)
- Panel: GBP 15.00 (out of stock - please enquire)
- Pre Programmed and tested PIC chip GBP 5.00 (in stock)
This is designed to replicate the user interface and most of the behaviours of the Roland 100m Mixer module, M-131.
- PCB: GBP 12.00 (low stock)
- Panel GBP 22.00 (in stock)
100m-ish VCO Driver
The VCO driver allows modulation, glide and octave switching to be easily applied to multiple VCOs. It is heavily based on the circuits from the Roland system 100m 180 and 181 keyboard controllers.
- PCB GBP 8.00 (low stock)
- Panel GBP 15.00 (in stock)
100m-ish High pass filter (HPF)
Frequency Central makes an excellent version of the Roland System 100m M-121 VCF, but it does not include the switched HPF that was in the original Roland module.
This simple module is designed to replicate the fixed 6dB/octave high pass filter from the Roland 100m M-121 VCF module.
Ideal as a first Eurorack DIY project!
- PCB GBP 6.00 (in stock) - the price includes 2 slide switches.
- FR4 Panel GBP 5.00 (in stock)
Aluminium Panel GBP 12.00 (in stock)
100m-ish Ring Modulator
- This module is designed to replicate the Ring Modulator from the Roland 100m M-150 module.
An additional “Mix” output has been added which allows mixing of the two inputs (X and Y) with the ring modulated signal.
- Build manual: PDF
- PCB GBP 8.00 (low stock)
- Panel GBP 12.00 (low stock)
100m-ish Signal Gate
This module is designed to replicate the Roland 100m Signal Gate module, M-173. The module comprises four analogue switches, each having a positive and negative control input. The circuit keeps the original Roland circuitry for processing the control signals, but uses a DG412 analogue switch IC for the signal switching, replacing and simplifying the discrete circuitry in the original Roland unit. The module includes two multiples. FR4 (White on black PCB) and 2mm aluminium panels are now available.
- Build manual PDF
PCB GBP 7.50 (in stock)
FR4 Black Panel GBP 7.50 (in stock)
For orders and enquiries, contact me at email@example.com