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previous: Mike I have a TS9 reissue with a 7550 ch... -- 8/11/1999 11:18 PM View Thread

Re: TS9 Upgrade?

8/12/1999 3:00 AM
Mark HammerRe: TS9 Upgrade?
There has been MUCH dialogue in this forum about replacement chips for TS-9's that produce a sound that appeals to more ears. I'm not sure what happened to those threads, but you can find much of that information summarized very nicely at both RG Keen's site ( and at Jack Orman's site (  
The short version is that there are a number of dual op-amps besides the now legendary JRC4558D that appear to have promising characteristics. Jack Orman has speculated about why this is, and what can be done to simulate that characteristics, regardless of what op-amp one is using.  
A simple way to identify the proper orientation of an op-amp on the PC board is to simply look for the ground pin and V+ pin. Most FX use a single-ended +9V battery supply, with the #4 pin going to ground, and the #8 pin going to V+). If you do decide to yank the dual op-amp from your reissue TS9, the smart thing to do is to solder in an 8-pin IC socket so you can try out different op-amps. The socket itself will have a little notch between pins 1 and 8,.

mike Mark, I don't see any n... -- 8/12/1999 9:11 PM