CV-3 MIDI-CV Converter Review

[gstopp at fibermux.com]

     Okay, don't read this Kyle!
     
     Yes I did open it up, soon as got it... geek that I am....
     
     Let me see what I can remember about what I saw... okay there's a PLCC 
     in a socket, I think 44-pin, plus the EPROM which is a 27C512. Then 
     there's a few op-amps, a couple LM358's I think, and an opto-isolator 
     or two. There's a DIP-8 MAXIM MAX-something, I ferget. Near where the 
     audio coax hits the PCB there's one or two 14- or 16-pin packages, 
     plus a couple of DIP-8's I believe. There is a 4066 in there too I 
     think. All of the interesting chips have had their top surfaces 
     *sanded blank*, including the PLCC which I suspect is the CPU.
     
     Clearly JKJ is interested in maintaining the proprietary nature of 
     their product in a slim vertical marketplace, which is quite 
     understandable, and I will without hesitation respect that desire. 
     Based on this fact, combined with the clean layout and obvious care 
     taken to signal routing, I get the feeling that there is some very 
     good engineering going on here.
     
     It looks like everything is going on in the code - no obvious external 
     voltage-controlled lag circuitry or sample and holds. From the low 
     parts count I'd say there's only a single DAC, probably one of those 
     high-falutin' high-bit-count serial jobbers. I'd guess that there are 
     at least a couple S/H circuits, since there are three panel CV's, but 
     they're just not obvious. I may be wrong.
     
     Anyway whatever's going on appears to be extremely clever. I have 
     absolutely no aspiration to reverse engineer it, frankly because for 
     the time, energy, and effort I feel that what you're buying here is a 
     total bargain. It's really amazing what kind of space-program code you 
     can buy these days, in our crazy little boxes!
     
     Hope I didn't reveal too much, Kyle! Well ya can't put a ban on 
     screwdrivers I guess....
     
     - Gene
     gstopp at fibermux.com


______________________________ Reply Separator _________________________________
Subject: Re: CV-3 MIDI-CV Converter Review
Author:  Christopher_List at sonymusic.com at ccrelayout
Date:    12/17/96 6:39 PM
     
       > Anyway there's the scoop on the CV-3 box from a user's standpoint.
     
  Awww c'mon Gene - we want to hear about it from the GEEK's standpoint!
     
  What kind of DAC?
  (or) What's the bit resolution?
  How many DACs?
  What kind of processor?
  Glide done with VCable hardware on the output pitch-CV - or in the 
  firmware before the pitch is DACed?
  What do they use for a VCA for the audio? Can (are?) the control voltages 
  for the audio VCA (be) routed to the front panel?
     
  This isn't AH yer talkin' to afterall!
     
  :)
     
  - CList