wdao@castor.usc.edu (Walter Dao) (03/16/90)
In this month issue of Popular Electroniss (april 1990) there is a little circuit that you can build that will improve the quality of digitised sounds. It is supposed to do some extra filtering and do some fiddling with the sound and make it more process-able by the available sound digitisers. Looking at the circuit, it looks pretty easy to build (I am not an EE. but even for me, it looks pretty easy). The sound source plugs into this gizmo and the output goes into the input of the digitiser. Why Am i posting it here ? because the authorsaid that he made it for and used it with an amiga system and it works extremely well. (perhaps biased but any increase in sound quality is more than welcome for any digitiser). ohhh , by the way, the gyzmo's name is called the "ditherizer". This was just for your interest . Walter (you bet I am gonna build it).
fc@lexicon.com (Frank Cunningham) (03/17/90)
In article <8649@chaph.usc.edu> wdao@castor.usc.edu (Walter Dao) writes: > In this month issue of Popular Electroniss (april 1990) there is a little > circuit that you can build that will improve the quality of digitised sounds. > It is supposed to do some extra filtering and do some fiddling with the sound > and make it more process-able by the available sound digitisers. > .... > ohhh , by the way, the gyzmo's name is called the "ditherizer". ^^^^^^^^^^^^^ Dithering is often used in professional audio systems to improve the low level performance of A-D convertors and DSP stages. To dither a signal, one adds noise to it at a level of around the LSB, ahead of the A-D convertor, thus randomizing the conversion. The randomized conversion has uncorrelated noise added instead of the correlated and usually inharmonic stuff that results from converting music to square waves (which is what you get if the low level parts of the signal wiggle only the LSB). -- -Frank Cunningham smart: fc@lexicon.com phone: (617) 891-6790 dumb: {husc6,linus,harvard,bbn}!spdcc!lexicon!fc snail: Lexicon Inc. 100 Beaver St. Waltham MA 02174 Why are viola jokes so short ? So violinists can remember them.