Very short delay times

[bancika]

Hi,

is it possible to make a simple delay that has only one echo and variable delay time between 5ms and 50ms or something like that. Is PT2399 suitable for that, can it go that low on delay time?

Tnx,
Bane

[frequencycentral]

A PT2399 can get into the 18ms to 20ms region with pin 6 grounded and using a 6v regulator instead of a 5v regulator - still within the chip's tolerance too.

[culturejam]

A PT2399 can get into the 18ms to 20ms region with pin 6 grounded and using a 6v regulator instead of a 5v regulator - still within the chip's tolerance too.

I think I saw in the Little Angel thread that you can also use a 5v regulator and add a diode between the ground pin and ground to get the voltage bumped up by the amount of the diode drop.

[PRR]

Are 128 or 256 stage BBDs still available?

We hated them because they only did short delays.

100ips tape, ugh.

25 feet garden hose, speaker, microphone. Don't giggle; we used to do that. There was even a commercial product. If it prototypes acceptably, PEX tubing may give lower loss.

[Scruffie]

Not as simple as a PT2399 but if you put a 3007, 3207 or 3208 chip in this (I'll post up the 300X to 320X converted schematic soon, it's quite easy to work out though and that schematic is verified) that should do the job - http://www.diystompboxes.com/smfforum/index.php?topic=87488.0

[Processaurus]

You might want to take a peak into the PT2396's "easy mode".  You can't continuously vary the delay time, but can get a range of hi-fi digital delay from ~10ms to 200ms with one IC.  Shorter delays are possible than the PT2399.  I was looking at it for stereo widening/fake surround sound type effects.  BBD's are still probably a viable solution for very short delays. 

http://experimentalistsanonymous.com/diy/Datasheets/PT2396.pdf