Tube Amps / Music Electronics
For current discussions, please visit Music Electronics Forum. The sunn still shines online!

ampage archive

Vintage threads from the first ten years

Search for:  Mode:  

Mesa Boogie 5-band eq

7/15/1999 12:35 PM
Mesa Boogie 5-band eq
I'm planning on using the mesa boogie 5band eq as a starting point to designing a multiband eq for my amp. If someone could help me on the corrections, I would be most appreciative! (It's scheme. is in Aspen Pittmans book). So anyway, I see it as basically a differential amp... Q1 just matches the input impedance, Q4 gives extra current output. The base of Q2 is the inverting input and the base of Q3 is the positive input. So, that's how I see it should be! O.K., The LC feedback loop should be connected from the output, not the pos. input, to inverting input. Q2 should have a load resistor to the negative rail... Q4 should have it's emmitter connected between the 3.3k r and the .01 output cap (otherwise Q4 isn't providing output current). I have a great article from Audio Electronics, by Nelson Pass on building class-A, discrete op-amps, which includes building high voltage op-amps! (issue 1 1999). I just noticed, the input polarity in his article seems incorrect- So please someone help!

Eddie Van Halen Eth- So what you're asking is, for... -- 7/16/1999 1:28 AM