[sdiy] Single chip digital delay

[Seb Francis]

Andre Majorel wrote:

>On 2006-01-24 11:54 +0000, Seb Francis wrote:
>
>  
>
>>On the subject of delays.. I've been wanting to build a simple digital 
>>delay (or two) for the purpose of making a wide stereo image .. e.g. 
>>hard pan the original sound to one side and hard pan a few ms delay of 
>>the sound to the other side.
>>
>>The delay needs to be clean and accurate (so BBDs are out!), and the 
>>delay time doesn't need to be very long.  I guess what I need is 
>>something like a good quality single chip digital delay.  Anybody know 
>>of something suitable?
>>    
>>
>
>There's Ryan Williams' VC-echo based on the PT239x :
>
>  http://www.sdiy.org/destrukto/vc-echo.html
>
>Ryan says the PT2396 can go down to 12 ms. But for realistic
>stereo placement, you want 0.5 ms or less.
>
>  
>
I don't agree, I tend to use times between about 3 and 35 ms.  Important 
is that the sound quality is good enough so the delayed signal sounds 
virtually identical to the original (although it is also interesting to 
EQ one side differently to the other).  Really I try and avoid very 
short delays (i.e. keep time above 10ms or so) otherwise you will get 
mono-compatibility problems.

Thanks for the pointer though.

Seb