All about the Roland Jupiter-series

Date: Sun, 31 Mar 2002 14:08:27 +0800
From: "drew" <hoovertime@...>
Subject: RE: [AH] checking mks-80 voices?

for the archive......

ok after checking the jupiter-6 service notes seems the mks-80 works the
same, theres a jig switch on the processor baord the bottom one near the
front right hand side, switch this to "jig" after power up.

seems like the mks-80 must be closer to the jp-6 after all ;D

-----Original Message-----
From: drew [mailto:hoovertime@...]
Sent: Sunday, 31 March 2002 12:18 PM
To: Ah
Subject: [AH] checking mks-80 voices?

hi,
recently purchased a version 4 mks-80 of evil bay, & turns out 2 of the
voices are playing up.
I dont have the service notes, so what is the procedure to put the mks80 in
the "check the voices mode" ? ;D

ive checked the archive to no avail, but did find this which seems apparent
in my mks-80.

"I've seen a few MKS80s in my day and two of them had dead CEM
3360 dual VCA chips in them. Check to see if you hear any bleed-through
when no voices are playing........."

one of the voices just seems to lay low with constant sustain, avoiding all
envelope settings etc......

until then...........

------------------------------

Date: Sun, 31 Mar 2002 14:31:11 +0100
From: "Colin Fraser" <colin@...>
Subject: RE: [AH] checking mks-80 voices?

> seems like the mks-80 must be closer to the jp-6 after all ;D

The MKS80 is more like a Jupiter 8/6 debate has been going on for a long
while, with even a Sound On Sound journalist (and listmember ?)saying
the MKS is more like a Jupiter 8 -
http://www.sospubs.co.uk/sos/feb98/articles/rolandjupiter.html - "the
MKS80 had nothing to do with the Jupiter 6". I disagree.
The voice boards in the Rev 4 MKS80 are nearly identical to the JP6
boards - basically they've just moved a few bits around and changed the
filters from hi-band-low to low pass plus Juno-style high pass.
Compare an MKS80 Rev 4 board -
http://www.ftg.co.uk/studio/mks/images/MKS80inside.jpg
with a JP6 board - http://www.colinfraser.com/misc/jp6vb.jpg
The layout around the slave CPU, the sample and hold sections and the
oscillators is the same.
The differences creep in around the filters/VCAs, and the connectors are
jiggled around a bit, with the bender board connector gone from the MKS
for obvious reasons. There can't be any doubt that the MKS80 voice board
is based on the JP6.
Soundwise, the biggest difference between 6 and 80 is going to be the
filters. Can anyone with the MKS80 schematics confirm whether the Rev 4
uses the IR3109 configured as state-variables, or standard OTA four-pole
low pass ?
That's likely to be the only factor that makes the MKS80 more like a JP8
than a JP6.

Colin f