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Message

Betr: Re: [Simmons Drums] SDS-III vs SDS-IV internally

2007-04-02 by Berk Aarts

can anyone get the schematics online
like to see what you guys are talking about
BERK!
>-- Oorspronkelijk bericht --
>To: <Simmons_Drums@yahoogroups.com>
>From: <jesper@...>
>Date: Mon, 2 Apr 2007 16:49:44 +0200
>Subject: Re: [Simmons Drums] SDS-III vs SDS-IV internally
>Reply-To: Simmons_Drums@yahoogroups.com
>
>
>Double checked the schematics... The 3086's are drawn as full schematics
>and 
>not standard IC's, that's why I missed them. Sure looks like the same setup.
>If anyone tech-skilled want to look at the SDS-III schematics I'm having
>
>suspicious thoughts of the 1458 in the top right corner on the schematics.
>
>Pin 1 gives just 1/10 of the value on the corresponding channel. As I 
>interpret the circuitry this directly affects the tone/noise pot (which
is
>
>fully functional BTW).
>
>What does the LFO section offer then? Doesn't look that impressive on the
>
>schematics. Time to mod the SDS-IV maybe? Trying to read pictures 
>online+schematics getting this;
>
>LFO speed (slow->fast)
>range: slow/fast
>LFO shape: square/sine
>LFO on/off
>run time (short->long)
>run on/off
>output level
>
>So the SDS-III has no waveform control. interesting, I didn't know this...
>
>electronically yours, jesper
>- -- --- ---- ----- ---- --- -- -
>www.electronic-obsession.se
>
>Order your own copy of the Machinepop/Imiafan
>split-EP at www.electronic-obsession.se/label.asp
>
>"Varför har du så många pianon?" (Nora Persson, 9 år)
>
>----- Original Message ----- 
>From: <michael.buchner@...>
>To: <Simmons_Drums@...m>
>Sent: Monday, April 02, 2007 3:49 PM
>Subject: Re: [Simmons Drums] SDS-III vs SDS-IV internally
>
>
>Hi Jesper,
>this is exactly the thing I want to know. The III is the four channel 
>device, as far as I know and the IV the two channel device, but the IV is
>
>not only half III. The IV has no master section with run generator and lfo,
>
>but may be the single channel is also different to the III.
>I repaired Wolfgangs III two month ago. It has no oscillators at all, the
>
>tone is nothing but a resonating ladder filter, copied 1:1 from good old
>bob 
>moog. If you turn the Noise/Tone pot to noise, the resonance is completely
>
>off, so also the impact click will not be audible. But on my schematics
of
>
>the III there are 3 3086 per channel, these are containing transistor arrays
>
>to build this filter.
>What I am wondering about is this pot on the IV called "Waveshape". Is this
>
>an osc or only an lfo? Maybe a good photo of both solder side and parts
side
>
>would help.
>Michael
>  ----- Original Message ----- 
>  From: jesper@...
>  To: Simmons_Drums@yahoogroups.com
>  Sent: Monday, April 02, 2007 3:01 PM
>  Subject: [Simmons Drums] SDS-III vs SDS-IV internally
>
>
>  Hi List!
>
>  I'm looking inside my newly arrived SDS-IV due to a dead oscillator and
>
>I'm
>  comparing it to the schematics of SDS-III. Is it just me or aren't they
>  alike? There are no 3086's on the SDS-III schematics but quite a few in
>
>the
>  SDS-IV...
>
>  Anyone with a SDS-IV schematic around?
>
>  electronically yours, jesper
>  - -- --- ---- ----- ---- --- -- -
>  www.electronic-obsession.se
>
>  Order your own copy of the Machinepop/Imiafan
>  split-EP at www.electronic-obsession.se/label.asp
>
>  "Varför har du så många pianon?" (Nora Persson, 9 år)
>
>
>
>
>
>[Non-text portions of this message have been removed]
>
>
>
>
>Yahoo! Groups Links
>
>
>
>


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