EQ modding headphones

[kensuguro]

I just got Max Virtual's Cynaps bone conduction headphones. I've been a fan of bone conduction headphones not for any audio work but more for making calls and listening to crap while I work etc. Max Virtual's a kickstarter type of thing where I think one guy or a small team is 3D printing components and piecing them together. I got the "big" version of Cynaps with 2W drivers so they have better range than other bone conduction headphones that pretty much use ear bud drivers. Still not great range, but better.

The problem with bone conduction is that they're extremely unbalanced EQ wise. So I tried counter EQing back to where it should be, and got pretty good results. Still can't beat its physical limitations on range, but what sound it does produce is closer to truth.

In fact, I think that's the issue with a lot of sub par headphones.. besides the physical limitations, I think the can be EQ'd to a much more flatter response.. maybe we just 3-4 bands of paraEQ. (low mid high fixed band/Q types won't work) I was wondering, can't you just graft some sort of circuitry into the headphones so they're tuned correctly? Maybe it's a costly way to fix an acoustical problem, but if the circuitry is cheap and tiny, it seems all it takes is a measuring mic and an automated way to produce the correct EQ parameters and you'd have calibrated output. All without necessarily needing to use expensive drivers. I mean, it's not a true solution, but I think it'll at least bring the best out of what you have. I think this is precisely providing a software solution to a hardware problem. Sometimes it's cheaper that way. (like digital cameras processing the fuck out of CCD input)

Does such a thing exist? Like a teeny tiny EQ pcb board with an EQ chip that can easily be retrofitted into headphones. Or I guess maybe a phone jack pass through could work. (like a guitar pedal for headphones) I think the key is that once the EQ settings are found, they don't require further tuning unless the driver characteristics significantly change. So that means you don't really need knobs and such to control the EQ. Just enough DSP to apply a preset. Bigger question yet.. has this been done? Did I just miss it?

[dante]

Might have been done but possibly a bit redundant as half the world probably listens on iDevices which have EQ settings inbuilt.

I listen on iPhone so can go to settings and compensate for too much bass in these Marley earbuds, or simply dont have them poked in ear as much.

But, if you really want to drill down on this, check out HeadFI

http://www.head-fi.org/t/413900/how-to- ... a-tutorial

This doesnt have a hardware solution you're after, but outlines the theory behind the problem and points to software solutions.

[garyb]

using eqs really wrecks a monitor. if it's not correct to begin with, an eq is a very messy fix.

of course, if they're something cheap, it probably doesn't matter.

[kensuguro]

ya, not for monitors. If they needed substantial eqing to fix then that's a separate problem. Like you say, it's more for cheap stuff. I was hoping cheap cans + cheap chip = not completely fucked up. There are also tons of lower grade headphones with boosted lows etc that actually might not be that bad if they were eq'd back to a more neutral response. Maybe I'm imagining these circuits to be much cheaper than they actually are.

[garyb]

any monitor should be tuned for an enjoyable response, not just reference monitors. i was just saying that an eq filter makes further problems. i don't see the point in making a product with a transducer that doesn't do a good job in the system already(eq might be useful at that point), but that's just my problem...

imagine a cheap filter on a bad-sounding source. it seems nasty.

[tlaskows]

I'm not sure, but I think EQ can bring all sort of phase alignment issues.

-Tom

[Nestor]

All this stuff rather scares me, I fear losing my natural capacity of hearing with those inventions. It’s probable nothing but ignorance from my part, but I would be careful

[jksuperstar]

I think there's already all kinds of phase alignment issues using both the ear drum, and the skull to transfer sound through.

Maybe you can put on the headphones, and subjectively EQ to match an external set of speakers that are already tuned, and simply A-B them throughout a sine-sweep. After all, your bones probably sound different from many other people. In essence, you'd be ditching the usual A-weighting (and B,C,D for that matter) for your own custom Ken-scale.

Then again, people's ears are also custom, and likely why many people prefer one set of cans over another.

[dawman]

I always thought an audiologist making an audiograph was pretty cool.
Maybe have an audiograph done and send it to the manufacturer.
4k notch is always a culprit.