Synth-DIY Yahoo! Groups Archives

Simmons SDSV tom tom noise generator issue

2016-05-09 by tubmyk2@...

Hello, first post in the group.

Just got an early SDSV SN# 362 with 5 modules; Bass, Snare, 2 Tom Toms and a digital HH. The HH might have been added later? But all boards are the early Rev1 style. I also, from a different source, got (6) SDSV black riot-shield pads, (1) SDS7 rubber pad, (1) SDS9 bass drum with the floating trigger, a possibly-rare or homemade cymbal with piezo, and have an additional Tom Tom module on the way in the next couple of days to complete the set for my liking.

One of the toms is having a problem generating noise. None of the noise adjustments work on the panel (including the mini trimpots) on that particular module. I cannot get that nice 'tssshh' sound behind the tom sound on this one. The other one is working fine. So far everything else seems to be working fine.

I'd already re-tinned the contacts on all the cards, just to make sure everything was seating correctly, and had to adjust the R28(?) internal trimpot on the toms and hi hat to center the audio. I really just guessed on this one as it was the first stop after the L/R outputs tracing backwards. The noise issue was there prior to me changing anything.

Is there an internal trimpot that adjusts the noise level? Or I'll ask it like this: what determines the factory 'un-altered' sound? I'm asking this because both of my tom tom cards have different factory presets, like one is low and one is hi, but if the modules are all the same, I would think they would have to be set to determine one was higher or lower, no?

For the noise issue, I'm hoping it was just someone screwing around with the internal trimpots and messed up the "calibration". If not, I am seeing that IC13, LM301, is the responsible noise generator?

Mike

Re: [Simmons Drums] Simmons SDSV tom tom noise generator issue

2016-05-13 by Nick Zampiello

it's probably whatever chip generates the noise. i've had this happen before.

NEW ALLIANCE EAST!!!!

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

New Alliance East - Mastering
New Alliance East - Facebook

X :::: B :::: S

On Wednesday, May 11, 2016 2:52 PM, "tubmyk2@... [Simmons_Drums]" <Simmons_Drums@yahoogroups.com> wrote:

Hello, first post in the group.

Just got an early SDSV SN# 362 with 5 modules; Bass, Snare, 2 Tom Toms and a digital HH. The HH might have been added later? But all boards are the early Rev1 style. I also, from a different source, got (6) SDSV black riot-shield pads, (1) SDS7 rubber pad, (1) SDS9 bass drum with the floating trigger, a possibly-rare or homemade cymbal with piezo, and have an additional Tom Tom module on the way in the next couple of days to complete the set for my liking.

One of the toms is having a problem generating noise. None of the noise adjustments work on the panel (including the mini trimpots) on that particular module. I cannot get that nice 'tssshh' sound behind the tom sound on this one. The other one is working fine. So far everything else seems to be working fine.

I'd already re-tinned the contacts on all the cards, just to make sure everything was seating correctly, and had to adjust the R28(?) internal trimpot on the toms and hi hat to center the audio. I really just guessed on this one as it was the first stop after the L/R outputs tracing backwards. The noise issue was there prior to me changing anything.

Is there an internal trimpot that adjusts the noise level? Or I'll ask it like this: what determines the factory 'un-altered' sound? I'm asking this because both of my tom tom cards have different factory presets, like one is low and one is hi, but if the modules are all the same, I would think they would have to be set to determine one was higher or lower, no?

For the noise issue, I'm hoping it was just someone screwing around with the internal trimpots and messed up the "calibration". If not, I am seeing that IC13, LM301, is the responsible noise generator?

Mike

Re: [Simmons Drums] Simmons SDSV tom tom noise generator issue

2016-05-13 by Michael Buchner

Do you hear any noise on the tom or nothing? If yes, change the IC 14 (1468), this is the noise CV summing amp. If no, check the noise amp IC 13 at pin 6, there has to be noise present. Pot R25 is responsible for the noise sweep/bend and pot 71 is noise volume by the way.

If yes, the SSM 2044 is dead.

----- Original Message -----

From: Nick Zampiello newallianceeast@... [Simmons_Drums]

To: Simmons_Drums@yahoogroups.com

Sent: Friday, May 13, 2016 4:20 PM

Subject: Re: [Simmons Drums] Simmons SDSV tom tom noise generator issue

it's probably whatever chip generates the noise. i've had this happen before.

NEW ALLIANCE EAST!!!!

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

New Alliance East - Mastering
New Alliance East - Facebook

X :::: B :::: S

On Wednesday, May 11, 2016 2:52 PM, "tubmyk2@... [Simmons_Drums]" <Simmons_Drums@yahoogroups.com> wrote:

Hello, first post in the group.

Just got an early SDSV SN# 362 with 5 modules; Bass, Snare, 2 Tom Toms and a digital HH. The HH might have been added later? But all boards are the early Rev1 style. I also, from a different source, got (6) SDSV black riot-shield pads, (1) SDS7 rubber pad, (1) SDS9 bass drum with the floating trigger, a possibly-rare or homemade cymbal with piezo, and have an additional Tom Tom module on the way in the next couple of days to complete the set for my liking.

One of the toms is having a problem generating noise. None of the noise adjustments work on the panel (including the mini trimpots) on that particular module. I cannot get that nice 'tssshh' sound behind the tom sound on this one. The other one is working fine. So far everything else seems to be working fine.

I'd already re-tinned the contacts on all the cards, just to make sure everything was seating correctly, and had to adjust the R28(?) internal trimpot on the toms and hi hat to center the audio. I really just guessed on this one as it was the first stop after the L/R outputs tracing backwards. The noise issue was there prior to me changing anything.

Is there an internal trimpot that adjusts the noise level? Or I'll ask it like this: what determines the factory 'un-altered' sound? I'm asking this because both of my tom tom cards have different factory presets, like one is low and one is hi, but if the modules are all the same, I would think they would have to be set to determine one was higher or lower, no?

For the noise issue, I'm hoping it was just someone screwing around with the internal trimpots and messed up the "calibration". If not, I am seeing that IC13, LM301, is the responsible noise generator?

Mike

Re: [Simmons Drums] Simmons SDSV tom tom noise generator issue

2016-05-16 by tubmyk2@...

Michael,

I partly wish I saw this before I went ahead and ordered up a couple of spare SSM2044 chips to have on hand, because you were 100% dead on about IC14, and IC3 also decided to blow up as well. I removed the SSM and replaced with a new socket and chip, and that made no difference, so I went back to checking IC13 and 14 (on my own will figuring it had something to do with the noise output). It also helps to have a scope and a working module to compare readings to. I saw big differences in IC14 on the faulty card when compared to the working one. Fortunately, that in conjunction with IC13 (and I tested to make sure it was actually both chips and it was), the card is now working. Yay :)

But..

At the same time I had received another Tom Tom module in the mail which worked great on first test, but somehow when I plugged it back into the unit I must have shorted the pins or something because I blew up the 2044!! Not even thinking it could actually be the filter chip I went ahead and replaced 13 and 14 just for giggles but when it didn't fix the problem and I swapped out the SSM to find out it was good, talk about a huge letdown and lucky at the same time to have ordered the spares...