Author |
Message |
mi_dach
Joined: Dec 17, 2005 Posts: 133 Location: Sweden
|
Posted: Mon Jul 17, 2006 9:56 am Post subject:
request: casio mt-800 service manual |
|
|
just wondering if anyone has some internal details on the mt-800.. thanks |
|
Back to top
|
|
|
fabreeze
Joined: Mar 13, 2006 Posts: 9 Location: Olympia, WA
|
Posted: Fri Jun 17, 2011 8:46 pm Post subject:
casio mt-800 internals Subject description: mt-800 analog drum section |
|
|
I know your post is old but I just opened up an mt-800 and poked around. It has really nice analog drum sounds. Most of the drum circuits are encased in resin or something with many leads going into the pcb. There are 5 trim pots that change the decay of the drums and some will oscillate if turned up all the way. Unfortunately, the bassdrum does not, but it still has oompf!! There are a handful of resistors in a row that are all connected on one side forming a mixer before going into an opamp. There is silkscreen labels next to each resistor to tell what sound it is. The drum part of the snare and the noise part are mixed in separately. There are some rounded globs of solder near this area that are the trigger inputs for the individual drums. The snare and hihat don't really make any sound unless the rhythm generator is started and running. This is because the metallic cymbal/hihat sound and the white noise are both generated digitally by the surface mount microcontroller that is on the solder side of the pcb. They were the 2nd and 3rd pin down on the right side of the chip respectively. All in all, it would not be difficult to add volume controls for each drum sound, individual output jacks, trigger input jacks, decay knobs, and outputs for the metallic noise and white noise. I hope this helps someone!! |
|
Back to top
|
|
|
CYBERYOGI =CO=Windler
Joined: Aug 05, 2012 Posts: 10 Location: Germany
|
Posted: Sun Aug 05, 2012 8:58 pm Post subject:
|
|
|
A single dead drum sounds like a bad electrolytic capacitor. When they leak/ vapour out, they loose capacitance/increase resistance and so shorten the drum decay envelope until it disappears.
Also check for an accidentally misadjusted or dirty percussion envelope trimmer. (Mark previous positions with a felt pen before you adjust them.) _________________
Code: | MAY THE SOFTWARE BE WITH YOU!
*============================================================================*
CYBERYOGI Christian Oliver(=CO=) Windler
(teachmaster of LOGOLOGIE - the first cyberage-religion!)
!
*=============================ABANDON=THE=BRUTALITY==========================*
{http://weltenschule.de/e_index.html} |
|
|
Back to top
|
|
|
|