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General => Open Discussion => Topic started by: frankie5fingers on May 06, 2014, 01:54:43 AM

Title: Anyone Have Any Experience Stacking Delay Chips?
Post by: frankie5fingers on May 06, 2014, 01:54:43 AM
First the qualifier... I love delays, the more watery the better and I have a few including a TTE.  While I'm building the Zero Point I was thinking I'd like to try some mods on a BBE Two Timer I bought a while back.  I often stack OpAmps - is there anything to stacking the Coolaudio 3205 chips?  How about anything else - has anyone ever modded the Two Timer?
Thanks
Title: Re: Anyone Have Any Experience Stacking Delay Chips?
Post by: Scruffie on May 06, 2014, 02:08:29 AM
Sort of, you'd basically have parallel multiplexing there (although you can't just plop the other chip on top) which improves the sample rate of the BBD chip so basically the fidelity of the chip would improve.

Or you can of course run 2 BBDs in series for double the delay time with the associated components.
Title: Re: Anyone Have Any Experience Stacking Delay Chips?
Post by: frankie5fingers on May 06, 2014, 02:35:40 AM
Hi Scruff.  It's the fidelity I'm thinking about.  If not just plopping it on top of the other, how would I do it?  I understand running two in series with the other things for a longer delay time but I'm curious about ways to improve the depth of the delay tone...
Title: Re: Anyone Have Any Experience Stacking Delay Chips?
Post by: GrindCustoms on May 06, 2014, 02:40:52 AM
Quote from: frankie5fingers on May 06, 2014, 02:35:40 AM
Hi Scruff.  It's the fidelity I'm thinking about.  If not just plopping it on top of the other, how would I do it?  I understand running two in series with the other things for a longer delay time but I'm curious about ways to improve the depth of the delay tone...

You could make an adapter with vero, that has the pins to connect in actual socket, 2 sockets on adapter board with all the links to run them in parrallel.

If i understand correctly what Scruffie have said, by stacking them (parrallel) it's exactly what you are looking for that will happen.
Title: Re: Anyone Have Any Experience Stacking Delay Chips?
Post by: Scruffie on May 06, 2014, 02:47:48 AM
Read the SAD1024 datasheet, it covers parallel multiplexing and also using differential operation in conjunction with it for further improvements.

But you can't plop them on top of each other as the clock pins need to be reversed for the second BBD is all, however, with this you will not have the optimal bias point for the second chip, so it is better to give it a separate bias.
Title: Re: Anyone Have Any Experience Stacking Delay Chips?
Post by: frankie5fingers on May 06, 2014, 02:48:35 AM
Got it, thanks guys!!
Title: Re: Anyone Have Any Experience Stacking Delay Chips?
Post by: Scruffie on May 06, 2014, 02:49:58 AM
Quote from: frankie5fingers on May 06, 2014, 02:48:35 AM
Got it, thanks guys!!
I edited for a caveat.