the circuitry after the voice roms can cause a lot of problems if
things get disconnected or misconnected. after doing the pitch mod, i
had some distorted, bent sounds, coming out of the wrong outputs and
stuff, until i tracked down the original clock traces that were cut
with the pitch mod.
hope this helps,
greg

--- In tr-707@yahoogroups.com , JB Prater <philo_707@...> wrote:
>
> OK, I got all of the chips out of there, all intact and everything.
I went ahead and labeled them and tossed them loose in a static bag.
They should ship fine like that, I'll wrap them in bubble wrap.
>
> BTW, someone mentioned removing the gate array. I want to try and
replace that but am having zero luck getting it desoldered, does
anyone have any tips on how to do that On that point, if the gate
array had been fried, would it probably quit working entirely, or is
it possible that it would just malfunction. I cant think of what else
would be causing ALL of the sounds to be messed up and bent, I really
do think its the gate array.
>
>
>
>
> plutoniq9 <Plutonique9@...> wrote:
> Is this the same machine you broke the pin off the gate array On the
> other note, do you really have 707 ROM's to donate Of course, I
> really only need to borrow them 4 just enough time to make .bin dump's
> to the computer. Are they already removed from the machine & which
> machine are they comin' from
>
> Funny thing about eprom's is they they have a life cycle of about
> 100,000 cycles. Eventually everyone's 707/727 (or any eprom drum
> machine) is going to lose the sounds.....maybe all together, most
> probably all random. Making copies, however, would allow the data to
> be burned to new eproms or flash memory for replacment when that
happens.
>
> Thanks
>
> Ryan
>
>
> --- In tr-707@yahoogroups.com , JB Prater <philo_707@> wrote:
> >
> > I have ROM chips to donate to this project, shoot me an email.
> >
> > OK, so on the chip transplant subject, I've been doing a lot of
> that. The fried 707 is working much better--to recap, first, I lost
> the second sound in grouped sounds, then I lost everything but
> kick/hitom/ride and they sounded all bent. I fried a few chips, I
> guess.
> >
> > After swapping some chips, I now have all sounds except crash,
> even both sounds in a paired set (came back after replacing IC29,
> BTW). But they sound bent (although recognizable). Here's where it
> gets interesting: no crash -- I had a test pattern with a crash in
> it, but it didn't sound -- then as I powered down I got a brief crash
> as it turned off. Where it gets really interesting: the crash sound
> was unbent, it sounded totally normal. Odd, but seems to suggest that
> something is wrong with a crash related chip, doesn't it Anybody
> have any ideas as to what to replace first
> >
> >
> >
> >
> >
> > plutoniq9 <Plutonique9@> wrote:
> > Well, still waitin' on the eprom burner to get here from hong
> > kong....is it wrong to wait this long for a bong to arrive from hong
> > kong
> >
> > hehehe, just a lil' humor....
> >
> > But i haven't been idle. I programmed a VST module today that applies
> > Mu-law compression/expansion algorithm to samples. It will be
> > necessary to process all samples this way before gettin' them on the
> > 707/727 because;
> >
> > -Samples have a lot of quantized noise (like aliasing) if they aren't
> > compressed before converting them to 8-bit.
> >
> > -707, like most 80's machines, use a combination of compression +
> > expansion on the samples (compansion), so it would sound real bad if
> > they (samples) were burned in their native linear format, because the
> > expansion would still be applied by the de-mux chips. That's thoses
> > extra "envelopes" the schematics refer to, but they apply exponential
> > envelopes to restore sample dynamics.
> >
> > Also, when ripping sounds off eprom's, I can apply mu-law expansion to
> > them to restore their original dynamic content. This would be the most
> > accurate way to extract samples from old eprom drum machines......
> >
> > I'm itchin' 4 this eprom burner to come, can ya tell Also, does no
> > one have 707 eprom's to donate Some junk/parts boards out there I'm
> > broke....so i can't just grab one from evil bay :) Also, still lookin'
> > for v2.0 of the firmware.....maybe I'll drop a line to the AH/SDIY
list.
> >
> > Seeya
> >
> > Ryan
> >
> >
> >
> >
> >
> > ---------------------------------
> > YAHOO! GROUPS LINKS
> >
> >
> > Visit your group "tr-707" on the web.
> >
> > To unsubscribe from this group, send an email to:
> > tr-707-unsubscribe@yahoogroups.com
> >
> > Your use of Yahoo! Groups is subject to the Yahoo! Terms of
> Service.
> >
> >
> > ---------------------------------
> >
> >
> >
> >
> >
> > ---------------------------------
> > Blab-away for as little as 1 ¢/min. Make PC-to-Phone Calls using
> Yahoo! Messenger with Voice.
> >
>
>
>
>
>
>
>
> ---------------------------------
> YAHOO! GROUPS LINKS
>
>
> Visit your group "tr-707" on the web.
>
> To unsubscribe from this group, send an email to:
> tr-707-unsubscribe@yahoogroups.com
>
> Your use of Yahoo! Groups is subject to the Yahoo! Terms of
Service.
>
>
> ---------------------------------
>
>
>
>
>
> ---------------------------------
> New Yahoo! Messenger with Voice. Call regular phones from your PC
and save big.
>