[sdiy] Roland D-10 modifications

[Theo]

Hope I won't sound too patronizing, but...
I am afraid these modifications would bring you disappointment at most.
The D series are early digital synths, nearly all of the noise you hear
comes from the digital sound engine.
There is a noise gate build in, so most of the noise is only present when
you play a note.

Swapping opamps or changing other components will not help you,
because the noise does not come from "cheap" opamps but from the sound
engine.
A bigger power supply (bigger caps?) probably won't help, because there is
no net cycle hum to begin with.
There is a lot aliasing and clock noise is in the output of the synth engine
itself,
therefore adding ferrite breads to dampen digital crosstalk to the analogue
part won't bring much.

Since you say you are a beginner there might be serious hazard of damaging
the PCB.
For example adding ferrites would include cutting traces and reconnect them
thru a ferrite bread.

I would suggest you try to enjoy your D110 the way it is and try something
else
(for example building a SBM (single board modular) or a ASM1) as your first
project.
Might save you some disappointment and give you a nice DIY synth instead.

Theo


From: Yash <yashk2000 at yahoo.com>

> Hi Byron,
>
> Some questions:
>
> 1. How do I calculate how much bigger the caps need to be?
> 2. When you say better opamps, do you mean only rating-wise or
maufacturing
> quality-wise for same ratings?
> 3. How much bigger a power supply do I need (actually, in this respect
what
> does 'bigger' mean? Can I succeed by using hte same power supply but
> tweaking it to enable more juice, like putting in smaller resistors?)
> 4. What are ferrites? Where would you add them? What do you mean get the
> digital clock hash out of the analog chain? Is this related to quatization
> and/or zipper noise leaking into the analog outputs?
> 5. Since I'm a beginner, does it seem by my questions that these mods are
> beyond my capacity (:OP)
>
> I'd like to do it all myself.
>
> Regards,
>
> Yash.
>
>
> > -----Original Message-----
> > From: owner-synth-diy at dropmix.xs4all.nl
> >
> >
> > I concur with this thought.  I've known several techs who would put in
> > better opamps, bigger caps, etc in the analog output chain, and
> > beef up the
> > power supply.  In a couple of particular products, they'd add
> > some ferrites
> > and what not, trying to get the digital clock hash out of the
> > analog chain.
> > It's probably more work diagnosing why it's got problems than
> > figuring out a
> > fix.
> >
> > Byron Jacquot
> >
>
>
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