tilt eq schematic check

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Hi,

i have a question regarding a tilt eq design
i made a little schematic of a passive LC tilt eq with center freq about 730hz

it is controlled with a double lineat pot with resistor added to alter the characteristics more/less to NM (balance pot, which is a bit to expensive for me)

this will be a part of every channel of my summing mixer, so before the eq there will be a line trafo and the output of will go to a opamp with gain 2

can you tell me if this will even work?

An externally hosted image should be here but it was not working when we last tested it.


bests
alan
 
I had to look up "tilt eq" - I've seen/heard single-control tone controls that cut treble at one end and cut bass at the other, but don't think I've heard the term before.

Offhand, it looks like you need resistors between the wipers and the common output, or directly in series with the wipers, otherwise when you have the control at one extreme one of the wipers will short the signal directly to ground.

Other than that, I'd want to check out impedances of the inductance and capacitance at crossover frequency in comparison with the 100k (35k?) load, so there's not resonant and putting a big peak in the frequency response. It appears this loading will change with the wiper position, and will somewhat affect the frequency response. This may not be a problem as long as the response is flat at mid position.

What is the opamp circuit? I'm asking because the opamp circuit's input impedance will also slightly affect the response.

Perhaps the easiest no-math (but least rigorous and involving the most trial-and-error) way to find the best component values is to use a simulator such as LTspice, and tweak them, giving simulations for different values.
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.