Roland TR-707 ROM Expansion Kit

Harry Axten

"Coming soon for the Roland TR-707 and TR-727..."

via https://hkadesign.org.uk

"You asked for it, now here it is – a ROM expansion kit for the Roland TR-707 and TR-727. It gives the machine 8 banks of sounds you can select, including the stock sounds from both the TR-707 and TR-727, so you can turn one into the other (to an extent – more on this later).

Changing between 8 banks would be a bit cumbersome using toggle switches, and I didn’t want to spoil the machine’s futuristic looks either, so this time the bank switching is done by holding down one of the first 8 step keys while turning the machine on. The setting is remembered and will be recalled the next time it’s turned on. There are no modifications to the outside of the machine, and the installation is easily reversible.

Apart from having different sounds, a modified TR-707 / TR-727 behaves exactly the same as a stock unit, no functions are lost. The machine should also be compatible with any other modifications or circuit bends you may have fitted, such as voice tuning, hi-hat decay mods etc.

I’d like to extend a huge thank you to Sunshine Jones, who donated the TR-727 which I used to develop the modification, and who also provided the excellent TR-808 and TR-909 samples which were used in the expansion banks.

The 8 banks included are :

TR-707
TR-727
TR-808
TR-909
LinnDrum
LM-1
DMX

TR-707 + TR-727 mix (handy for those who don’t own both machines)
The ROM expansion kit will switch out all of the sounds (referred to as a bank) apart from the last two sounds (crash + ride / quijada + chime), which will remain the same across banks, as they are stored on their own ROMs in a different part of the machine. I may produce an optional add-on board that can switch these as well if there’s sufficient interest."