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previous: R.G. I just posted a DIY design for a tw... -- 10/6/1999 1:00 AM

Re: DIY Parametric EQ at GEO

10/6/1999 10:56 AM
GFR	Re: DIY Parametric EQ at GEO Note: the simple "graphic EQ" shown in the first schematic is exactly the same topology used in the MESA/Boogie amps, only the MESAs use a "discrete op-amp" (three transistors) instead of U1B. So if one wishes to build an inductor-less EQ for a boogie clone go and read RG's article. Also note that the simulated inductors are built around an op-amp wired as an unity gain amp. You don't need an op-amp for this: you can use a commom-collector transistor stage (the Boss Metalzone uses this trick).

10/6/1999 10:56 AM

GFR

Re: DIY Parametric EQ at GEO

Note: the simple "graphic EQ" shown in the first schematic is exactly the same topology used in the MESA/Boogie amps, only the MESAs use a "discrete op-amp" (three transistors) instead of U1B. So if one wishes to build an inductor-less EQ for a boogie clone go and read RG's article.

Also note that the simulated inductors are built around an op-amp wired as an unity gain amp. You don't need an op-amp for this: you can use a commom-collector transistor stage (the Boss Metalzone uses this trick).

Replies:

R.G. Yep, all correct. The LC filter sty... -- 10/6/1999 12:49 PM