Anyone tried EQ-ing their headphones?

[soldermizer]

OK, I admit it. I have never been true "audiophile." Gnawed around the edges of it, and left rat turds (posts on these forums I guess). Rodent fixation ... sorry. But I do like consider and try new ("to me") stuff. If you can get by the gag reflex that many audio-fools have about EQ being the work of Satan, here is a question: Do you use, or have you tried, some form of active EQ with your headphones? Being the recent owner of a pair of Stax Lambda (two pair actually)...I ran across this thread (url if interested):

http://www.head-fi.org/forum/thread/413900/how-to-equalize-your-headphones-a-tutorial

This for me was the ideal audio project because (A) it offers much tweaking possibilities and ( I'm broke, so no additonal money need be spent

I have more or less done as he recommends ... found a peak or two ... also I am trying subjective EQ with 1/3 octave pink noise bands. So far the results are good (I use the EQ for normal listening.) haven't done much A/B testing tho.

How much of the "sound" of headphones (speakers, rooms, etc) is due to just the different frequency responses? Do your $1000 headphones really sound better than the $50 pair,or is it just that 6K peak? Dare you find out?

-- Pedorrero, obviously deceived by the abyssmal quality of his Behringer DEQ2496 EQ (if only he'd turned on 24 bit dither, all would be in harmony in the universe.) ... ?

[Dreadhead]

In short: Yes

I also did measurements and other fun things:

I have a DEQ2496 and I would disagree about the abysmal part but that's my ears. I did a blind test with my Bel Canto DAC3 and a Weiss DAC2 and never heard any difference when volume matched and listening to music. YMMV I guess.

[purrin]

If you can get by the gag reflex that many audio-fools have about EQ being the work of Satan, here is a question: Do you use, or have you tried, some form of active EQ with your headphones? Being the recent owner of a pair of Stax Lambda (two pair actually)...I ran across this thread (url if interested):

I've on occasion shelved down the treble on the lambdas 2-3db from 1.5kHz upward. I don't bother trying to fine tune FR. It's kind of fruitless because most of the peaks are resonances or stored energy in the time domain that can't be really eliminated. And you are still going to get the same non-linear distortion relative to the signal anyways.

-- Pedorrero, obviously deceived by the abyssmal quality of his Behringer DEQ2496 EQ (if only he'd turned on 24 bit dither, all would be in harmony in the universe.) ... ?

The Behringer stuff is not too bad if you bypass the output stage after the DAC chips. The AKM chips have a voltage output. I think Behringer still uses the AKM4393, which doesn't sound too shabby to my ears. You can tap into the DAC chip output pins off the ribbon cable from the main board. Then either couple with a transformer or cap and feed your amp directly (assuming your amp is easy enough to drive directly from the chips.) Keep cable lengths short.

Edited July 7, 2011 by purrin

[acidbasement]

My isolating frankenorthos, on which I have no time to spend getting the damping right, sound great with a huge amount of bass boost - way better than anything else that would let me listen in bed while my wife is trying to sleep. I have had pretty good results using an old NAD receiver with bass set to 3 o'clock. I'm currently in the middle of cleaning up a salvaged Yamaha RX-350 stereo receiver, and it has a loudness potentiometer (rather than a switch), which seems like it might sound better than just cranking up the bass on the NAD, though I haven't done any A/B comparisons yet.

[ktm]

I've on occasion shelved down the treble on the lambdas 2-3db from 1.5kHz upward. I don't bother trying to fine tune FR. It's kind of fruitless because most of the peaks are resonances or stored energy in the time domain that can't be really eliminated. And you are still going to get the same non-linear distortion relative to the signal anyways.

EQ isn't evil. Just worthless in fixing most flaws in sound. Like you, I have tried this with 404's, and in the end found 202's to just work better.

Until I can afford the really good Stax stuff, the 202's will have to do.

[soldermizer]

My first post was a bit flippant: actually, I am a satisfied Behringer DEQ2496 user (except I lost one to an electrical storm recently). If anything, I tend to be suspicious of the claims of the golden ears or whatever they're called nowadays. Some things I can hear ... the size of a room, or (perhaps) the quality of a headphone.

Here is a link to David Greisinger, a guy that has done a lot of interesting things with headphones:

http://www.slideserve.com/presentation/23730/Binaural-Hearing-Ear-Canals-and-Headphone-Equalization

The equipment is not available to me, but if Greisinger is right, then it would require a pair of his calibrated "ear drum" mics and the DSP stuff to truly EQ any given pair of headphones and ears. I think he (and others) make the case that, at least it seems reasonable to me that there will be a unique response (convolution?) for any given pair of cans and ears, it is probably unique, or nearly so. Some concepts easier to grasp than others...like you should only see very high pitch resonances inside the ear (due to the tiny distances: one inch would be about 14 Khz wave length);

For my purposes, I note, that even if you could EQ ruler flat per Greisinger, it still might not be "subjectively flat." So, I am playing with the 1/3 octave pink noise. Thus, the subjective method wins in cash terms...I can tune the phones to sound the way I want. In the mean time, putting green marker on my cds and raising my cables a foot off the floor will fix the other signal problems

[John Buchanan]

Stax did this with their ED-1 - an attempt to bend the frequency response of their Lambda Professional Earspeaker to the ideal diffuse field frequency response.

[arnaud]

I think if good sound for you equals a satisfying tonal balance beyond any other aspect of sound reproduction then I think equalizing (in case you're not found the right pair of headphones to sound ok for you) is a great way to get there cheap.

On the other hand, such filters, the more aggressive they are (slope), the more they affect (ruin imo) the response of a headphone when looking into the time domain (additional ringing) or when looking at the phase response. So I guess, if one goes by measurements, better make sure you don't only equalize by looking at the magnitude response but also check impulse / step response and the phase as well.

Overall, I would think some eq. used with parsimony, to slightly adjust a good headphone to start with may be beneficial to some but any heavy filtering is going to show its drawbacks quickly. For headphones, one nice thing is that they're single transducer and thus should not require such filtering up the chain (if they are reasonably flat in the first place). It feels like a step back to introduce filters back into the chain, I don't call this audiofoolness but rather "less is better" philosophy.

[nnotis]

I haven’t yet spent effort trying to EQ my headphones. But my experience EQing mic signals might be relevant. As a rule of thumb, I try not to boost any part of the spectrum more than 3 db. When I do, it’s never for very long, as the heavily boosted region always sounds a bit distorted. That said, some mics, like my Royer SF1 pair, seem to offer more leeway in this regard. And some EQ plug ins seem better suited to boosting than others. The bottom line is that there are a fair number of variables. Distortion from both the mic and the EQ plug are probably at play. I’d expect a similar relationship to exist for headphone playback.

[Dusty Chalk]

Sounds like an overhead problem -- you ought to try cutting all the other bands.

And: mmmm...Royer.

[nnotis]

I find reducing bands rather than boosting them leads to a better outcome.

Not a fan of the SF-1?