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previous: eric p The crappy sound is a very unpleasa... -- 11/10/1998 4:04 AM View Thread

Re: "Crappy" meaning distorted..

11/10/1998 12:35 PM
Mark Hammer
Re: "Crappy" meaning distorted..
The amount of storage space for any single sample is limited by the addressing capabilities of the device. So, say the gadget has 4 sec of sample length at 1khz bandwidth. Chances are that it will have at least 8k of static ram to store the sample (am I right in assuming that it retains samples after power down?). If this was the case, the on-board addressing will successfully count up as high 8192 addresses, and changing the pitch of the device will simply step it through those 8192 steps (dumping their contents to the D/A converter and output) faster or slower.  
If you were to stick 16k of memory in the same device, you would be able to use the 14th address line (8192 is a 13-bit address) on the RAM chip(s) to select sample A or sample B. Neither sample, however, could extend beyond the 13-bit address range because the counting circuitry on-board won't count any higher before it jumps back to the lowest address. Getting it to go further would entail a complete redesign, and that's not what you're looking for.  
It's entirely possible that the "crappiness" is the product of a/d or d/a conversion that goes astray after a little while for some reason. Given the price/age of the EH-SR, it probably uses 8-bit a/d conversion, and having even one of those bits off will almost necessarily produce sound quality that is sub-telephone quality.  
If it is indeed a product of faulty a/d conversion, and if you can trace the source and control it at will, you can have two effects for the price of one: replay and grttifier.