TR-707 querys..

Paul Maddox space_banana at
Wed Mar 11 15:00:50 CET 1998

>Ok.. The Situation is this.. .I phoned Roland Scandinavia and they 
>said that they obviously couldn=B4t give any information about the 
>sampleformat or anything like that..

suprise suprise, roland are like that... try asking if you can buy a 
schematic from them! you'll more likely to get a refund of the TAX man.

>But there is a guy that has put the rom of an 727 on top of the 
>707-rom and then put switches so that he had both machines in one.. . 
>But i couldn=B4t get a hold of him..

Chances are just a switch and resistor for the chip select.. or address 

>> The sounds in the 707/727s are pretty heavily companded.
>> I've heard that in truth they are only 6 bit resolution.
>Thinking of backwardsenginering.. .. Could anyone explain "briefly" 
>how you would do to identify the sampleformat .. How is it done? .. . 
>Anyone? ..

The way I did it with the PPG stuff, was to get copies of the contents 
of the chip onto a disk, put all the numbers (hex) into a spreadsheet 
and make a graph out of them, if its vagually cyclic (ie Waveform) you 
should be able to see it.. PPG used half wave samples (cunning, but 
effective).. The sample format is what is called RAW, ie it has no 
header or sample information, its just pure numbers.. chances are the 
rom data is probably 8 bit or 16bit at a push...

If you or anyone has got an eprom from this beasty I wouldn't mind a 
copy to see if I can extract the sounds and make a module out of it!


Paul Maddox

*  Modulus DIY Web Page ;-                        *
*  *
*  E-Mail ;-                                      *
*      Space_banana at                   *

Get Your Private, Free Email at

More information about the Synth-diy mailing list