Inductor for headphone EQ ?

[Paul W]

I'd like to build a passive EQ for a set of 300 ohm headphones. The task is to attenuate a 3db rise centered around 100Hz (low Q). Haven't run any sims yet, but I suspect the inductor for a parallel RLC in series with the phones will be large...perhaps requiring a core . What are the best core materials and construction for the job? Given the high load impedance, coil resistance probably doesn't have to be particularly low.

Recommended sources for parts of reasonable size?

[Tommythecat]

http://www.head-fi.org/forums/showthread.php?t=249871&highlight=behringer

I've never, ever seen anyone attempt what you're suggesting. I have no idea what kinds of parts values you should be expecting or what tolerance variation could do to the RLC's design. So here's a 15 band eq for 35 bucks.

[Paul W]

I'm using them with a DEQ2496 now but it seems like overkill...plus I can get more utility out of the phones with a sorta-portable passive box.

The inductor needs probably needs to be 10-15 mH and, after thinking about it a bit more, coil resistance somewhat low.

[Tommythecat]

Yeah, as i thought about it - it seemed like it would be difficult for portable use. That's why i recommended the EQ.

[Dennis H]

When in doubt, ask SL. He lists some parts from Mouser in that range.

http://www.linkwitzlab.com/reference_earphones.htm