delay chip

gkaiomenos · Post by **gkaiomenos** » 22 Dec 2007, 09:49

do you guys know of a delay chip with internal ram capable of 700ms up to 1s clean delay?

Brian M · Post by **Brian M** » 25 Dec 2007, 08:12

gkaiomenos wrote:do you guys know of a delay chip with internal ram capable of 700ms up to 1s clean delay?

Depends on what you mean by clean. Considering the size of a lot of the digital chips and the fact that most require external ram, you might look in to using 2 PT2399's instead.

gkaiomenos · Post by **gkaiomenos** » 26 Dec 2007, 09:39

thanks Brian

well i haven't thought of that possibility

I guess that you mean cascading the two chips and controlling clock/delay time from a single pot. right?

Brian M · Post by **Brian M** » 06 Jan 2008, 02:02

gkaiomenos wrote:thanks Brian

well i haven't thought of that possibility

I guess that you mean cascading the two chips and controlling clock/delay time from a single pot. right?

Yeah, although I dont think you can just connect a pot to each chip. Unfortunately I've never been able to find an internal schematic of the pt2399. Most likely you would have to use a single pot and a pair of transistors, and a few resistors. That's the way I've done a few prototypes and breadboard projects....

Or if size and knobs are not an issue, you could even do a dual tap delay and have two delays in series, each with a delay time, and level control, and a master feedback knob. Multitap delays can be really cool.

I've been working on something similar to this for a while. Of course the trick with the PT2399, or any delay really is the filtering.

gkaiomenos · Post by **gkaiomenos** » 06 Jan 2008, 10:45

how about a stereo pot?

bajaman · Post by **bajaman** » 06 Jan 2008, 11:10

how about a stereo pot?

are you asking where to purchase one from

if so - what size, what value, what resistance law, etc., please be more specific - then we may be able to help you

bajaman

analogguru · Post by **analogguru** » 06 Jan 2008, 11:46

I think this should read:

How´s about (the use of) a stereo-poti (to achieve the desired result) ?

analogguru

gkaiomenos · Post by **gkaiomenos** » 06 Jan 2008, 12:35

analogguru wrote:I think this should read:

How´s about (the use of) a stereo-poti (to achieve the desired result) ?

analogguru

lmkv15 · Post by **lmkv15** » 13 Jan 2008, 06:09

gkaiomenos wrote:do you guys know of a delay chip with internal ram capable of 700ms up to 1s clean delay?

Hi,

You can use the Holtek HT8955A. The delay time is up to 800ms. With lower tact up to 1s.
You need an external DRAM type 41256 (256Kx1).
Another chips are PT2395 with external DRAM, M50195.

Best regards Uwe