[xnor]

Take a look at #10. He pulled all sliders down but the 1 kHz one, but the response (purple line) is a wobbly mess. There should only be a peak at 1 kHz, the rest of the frequency response should be flat.

 

[Joe Bloggs]

On the other hand, if you simply boost the band you want to boost and push down the preamp slider to prevent clipping, the itunes equalizer should do pretty much as it's told.
 
BTW, not sure there was any analog equalizer that would yield a straight line frequency response when the sliders were anything but all zeroed.  Assuming the graphic EQ was just a series of fixed-frequency, fixed-Q filters, the response with all sliders pulled down would always look something like this:
 

 
It's only in the digital age that we can conceive of a graphic EQ giving flat response whenever all the sliders are level--but what one is thinking of in this case is not a conventional graphic EQ of the analog era, more like an on-the-fly filter calculator that fits the response curve to the slider positions, such that e.g. -10dB on all the sliders yields a flat -10dB curve.
 

 

[slayerming2]

Alright thanks for all the help guys!

 

[Spyro]

EQ only adds distortion if you can hear it.  This topic is W A Y over analyzed.  It is all dependent on the IEM's capabilities, period.  
 
With the exception of W4 all of Westone's and Shure"s IEM's react very well with EQ with no distortion.  But when I had UE900 (and TF10 for that matter), if I added a few dB's of bass to thicken up the sound it would distort right away.  To me, this is a sign of a very poorly engineered IEM.

 

[bigshot]

You can't squeeze blood from a stone.

 

[firev1]

Quote:

EQ only adds distortion if you can hear it.  This topic is W A Y over analyzed.  It is all dependent on the IEM's capabilities, period.  
 
With the exception of W4 all of Westone's and Shure"s IEM's react very well with EQ with no distortion.  But when I had UE900 (and TF10 for that matter), if I added a few dB's of bass to thicken up the sound it would distort right away.  To me, this is a sign of a very poorly engineered IEM.

 
Don't be stupid, if you add a few db of bass to TF10s already bloated bass, of course you will get distortion(TF10 by itself already has a long bass decay)! EQ done correctly as others have noted can help to really improve fidelity and can help lessen stored energy issues. Certainly not the cure all but a valuable tool.

 

[bigshot]

The transducer needs to be capable of producing a full range of sound in order for equalization to work properly. Once the response is balanced, it will probably more likely take pressure off the transducer and make it easier for it to get loud, rather than put pressure on and create blow out.

 

[ferday]

i have found that different cans respond quite differently to EQ...my grado sr80 respond quite audibly to very small (2dB) changes in much of the FR where my (much hated here) HD500's don't respond at all to my ears until i've hit >10dB in any of the mids or lower FR. my HE400's are also fairly sensitive, yet i've found that it takes EXTREME EQ to make them distort/clip.  my ATHM50's seem to respond best to moderate (4-5dB) changes in the entire FR
 
i should find my old mic and do some actual measuring when i have some time, but to me the differences are very audible
 
thanks to the magic of digital EQ i've made dozens of different EQ files for different cans/different music/different moods, all just a click away LOL

 

[xnor]

@Spyro: If a headphone/in-ear has boosted bass and not very low distortion to begin with then boosting the bass further, no matter how you do it, will result in more bloated bass and more distortion.
 
If you cut the bass you'll get a more balanced frequency response and lower distortion.

 

[Ahriakin]

Why care what it will do to a graph, or even how it looks from a detailed mathematical pov. If adding EQ makes the music more pleasing to you that should be enough, whether compensating for deficiencies in the listening pipeline or simply adjusting from the mastering engineer's taste to your own...Now, yes of course I wouldn't be here with ye fine gentlemen if I didn't also put a lot of thought into the tech needed to reach audio nirvana, It's just all to easy to get lost in the science when it should be about the art 

 

[bigshot]

The reason that a truly balanced response is a good thing is because of masking. An imbalance in one frequency can cover up the frequency an octave up. Get a bunch of bumps going, and your sound is going to be full of holes like swiss cheese.

With decent equipment, balanced sounds better. The only reason I can think of to boost frequencies unnaturally would be to make up for deficiencies in your headphones.

Flat response isn't about taste. It's about allowing all of the music to come through equally. That makes sound clearer, sharper and more detailed.

 

[Ahriakin]

Quote:

Flat response isn't about taste. It's about allowing all of the music to come through equally. That makes sound clearer, sharper and more detailed.

 
This is the part I disagree with - well mostly since the purist in me is screaming agreement . As part of the mixing and then mastering process EQ will have been used extensively by the engineers involved, you are not hearing the original performance. Now that is being done (hopefully) by a true professional with far more expertise than the listener but it is being done to reach (synthesize) a certain sound quality, which for better or worse comes down to taste (beyond the basics of making the mix technically clear and coherent). When you strive for a flat response through your audio pipeline you are aiming to closely emulate what the engineer/producer/artist have deliberately processed, which might not suit your own listening preferences.

 

[proton007]

Quote:

 
This is the part I disagree with - well mostly since the purist in me is screaming agreement . As part of the mixing and then mastering process EQ will have been used extensively by the engineers involved, you are not hearing the original performance. Now that is being done (hopefully) by a true professional with far more expertise than the listener but it is being done to reach (synthesize) a certain sound quality, which for better or worse comes down to taste (beyond the basics of making the mix technically clear and coherent). When you strive for a flat response through your audio pipeline you are aiming to closely emulate what the engineer/producer/artist have deliberately processed, which might not suit your own listening preferences.

 
You're right about hearing the right sound. However, audio equipment, especially the speakers aren't perfectly flat in their response (well, atleast the cheap to mid range ones aren't).
 
Which means if you want a flat output response, you'll have to compensate for the irregularities of the transducer. Lower the frequencies that it boosts, and turn up those it supresses. Hence EQ.

 

[bigshot]

An engineer has EQ on each and every channel. He uses that to make each of the channels stand out from each other, not muddle together into an aural blur. The goal is clarity in the mix through overall balances.

If you apply coloration through goosing the bass or treble, you do that across everything at the expense of overall clarity. It's like a chef creating a very carefully balanced blend of ingredients and spices, and then you pour ketchup all over it. All you taste is ketchup. Yes, maybe you like ketchup. But it's covering up what the chef created for you. You're never going to be able to taste what he was creating.

When I was a kid, I would turn up the bass and treble all the time. I thought "more is better". As I went along, I realized that there is an ideal balance to strike. It isn't easy to achieve a balanced response, but when you do just about everything sounds better. Clarity is the most obvious improvement that a balanced response brings.

 

[proton007]

Quote:

An engineer has EQ on each and every channel. He uses that to make each of the channels stand out from each other, not muddle together into an aural blur. The goal is clarity in the mix through overall balances.

If you apply coloration through goosing the bass or treble, you do that across everything at the expense of overall clarity. It's like a chef creating a very carefully balanced blend of ingredients and spices, and then you pour ketchup all over it. All you taste is ketchup. Yes, maybe you like ketchup. But it's covering up what the chef created for you. You're never going to be able to taste what he was creating.

When I was a kid, I would turn up the bass and treble all the time. I thought "more is better". As I went along, I realized that there is an ideal balance to strike. It isn't easy to achieve a balanced response, but when you do just about everything sounds better. Clarity is the most obvious improvement that a balanced response brings.

Its especially true of the higher frequencies. Make them too loud, and you'll start missing out on the mid range.