[sdiy] help finding roland filter schematics?

[Florian Anwander]

Hi Louis

> Can the SH-3A possibly be earlier than the SH-3?
> Then the swap would make sense.
>> If this diode ladder filter is an SH3, all the rumours on patent 
>> infringements in the SH3 (which shall have caused the change to SH3A) 
>> would be false. Now: why did roland change the filter design?
I don't think so.

The SH3 service manual says:
"applied to serial No.220100 - 220599
complete manual is typed by hand on a mechanical typewriter.

The SH3A service manual says
"applied from serial no. 270800"
it is appearently already layouted professionally
and it mentions three versions:
Serialnumber XX2549 and below
Serialnumber XX2550-XX3049
Serialnumber XX3050 and above

To me it looks clearly that the SH3A is produced after SH3.

Did anyone read the book of Ikutaro Kakehashi?

Florian