john12ax7
Well-known member
Was looking for some inexpensive EQs so figured this was a good candidate. It's not really a clone, but a bit of a redesign to incorporate some other features.
Here are some changes I made:
1) Input can accept a line receiver THAT1200, 1246, INA134, etc or a differential opamp.
2) Each EQ stage gets its own opamp, this removes the mid band interaction of the original (for better or worse), a wide selection of opamps can be used and mix / matched if desired.
3) Added relay hard bypass.
4) Output can be a line driver THAT1646, DRV134, etc or opamp impedance balanced.
Overall the results are good, both in terms of sound and noise, it holds it's own with some of the other EQs I have.
Mostly I just built these for myself but if there's interest I could make a kit available, total build cost would probably be $225-250 (US) per channel. It would be a significant lead time though (10-12 weeks) as some of the pots would need to be custom ordered, either that or hacksaw the shafts and use different (and bigger) knobs.
Here are some changes I made:
1) Input can accept a line receiver THAT1200, 1246, INA134, etc or a differential opamp.
2) Each EQ stage gets its own opamp, this removes the mid band interaction of the original (for better or worse), a wide selection of opamps can be used and mix / matched if desired.
3) Added relay hard bypass.
4) Output can be a line driver THAT1646, DRV134, etc or opamp impedance balanced.
Overall the results are good, both in terms of sound and noise, it holds it's own with some of the other EQs I have.
Mostly I just built these for myself but if there's interest I could make a kit available, total build cost would probably be $225-250 (US) per channel. It would be a significant lead time though (10-12 weeks) as some of the pots would need to be custom ordered, either that or hacksaw the shafts and use different (and bigger) knobs.