[sejarzo]

In another thread here discussing various options for someone asking advice on a new pair of headphones, Jaska posts something that seems to be a common finding, sound-wise, and posts a comparison graph from HeadRoom to explain.......

Quote:

Originally Posted by Jaska /img/forum/go_quote.gif .......The HD580 would probably be another good choice, though harder to drive than the rest of the pack. It's rare that people cite lack of bass quantity in the HD580, and weirdly, the measurements in that department are almost identical between the HD580 and the K501.

The graph in question:

I also find the common perception of the AKG's being bass-shy versus the similarly-priced Senn's to be an enigma, because of virtually the same comparison I made last year.....both audibly and when looking at the HeadRoom curves.

I use HD600's and thought I'd give the K601's a try to see if the AKG did indeed provide a wider soundstage. I'd found the K701's in a very brief trial to be extremely comfortable, but didn't want to spend so much on a second pair of cans at the time.

So....I bought some mint K601's from a Head-Fi'er who really likes Darth Beyers, so it was no surprise that he opted to sell, right?....but I found them very bass-shy and cold/sterile, though with a wider soundstage. Drove them with a Millett and a maxed-out desktop PIMETA, and they never excited me at all. I sold them in a month or so to another forum member, who PM'ed me in a few weeks, saying he found the signature to be pretty much in line with my findings....and he sold them, too.

Now take a look at this graph, comparing the HD600 and K601:

Huh, what? All the way up to 4 kHz, there is virtually no difference in the curves. Considering that the huge majority of musical energy exists in that range, and sound signature overall is primarily a frequency response issue, it seems almost incomprehensible that there's a general perception that the K601 is bass-shy/bright/sterile versus the Senns....but that was my definite conclusion.

Even more strangely......go to the HeadRoom pages for each of the headphones in question and a few others, and look at the curves displayed on each of those pages. My understanding is that the curves on a product's page represent each channel of a pair of that model....and the difference between left and right drivers in a single pair often is as much or more than the difference between the HD600 and the K601 in the comparison graph!

Something tells me that head/outer ear/ear canal shapes and dimensions have a lot more to do with how each of us perceive sound sigs than we realize.

Comments?

 

[Kevin Sinnott]

I read your post with interest. Something that's mystified me about my AKG 501s is how come the bass appears so much stronger using 701 pads. Would they measure the same? If they would, to me it renders measurements unhelpful in determining audible differences. In other words, I agree with your statement that other factors come into play, some in one's ears and some in the headphone's physical design, beyond electronic speaker performance. In this way, the ear pad design appears to be a factor similar a listening room's acoustics, where it's widely agreed that a pair of loudspeakers will sound different based upon their environment.

 

[egokun]

Judging from the curves, the AKGs do seem to have the bass, "objectively". Subjectively, I've had a very curious experience. When I first received my K701, I was used to the Westone UM2s, and the AKGs sounded shrill and lifeless. Now I feel that the K701 have deep and impactful bass; the problem is that the K701's soundstage is so wide that everything seems somewhat distant from you, and this may reduce bass impact (the bass is definitely there, audible and accurate). The curious thing is that, after I switched the tri-flanges with the Shure black olives on the UM2, this notoriously all-bass IEM suddenly changed its sound signature to something not so different from the K701: the highs are much more prominent, sibilance can be a problem with some singers, and most surprising of all, the bass is almost level with the K701's, ie not boomy nor prominent at all, but tight and articulate. I am surprised by how much more similar these two phones sound to me now

 

[ph0rk]

The human ear is more sensitive in the middle ranges.
See:

Physics Tutorial 2: The Physics of Hearing — Audioholics Home Theater Reviews and News


When you set the volume on a given headhone, it is those peak areas on the inverted loudness curve that you're setting, so if any two given headphones have the "same" bass on a headphone.com curve, they may not when set at equal perceived loudness, as the headphone.com curves are matched at 600 hz, not 1khz or 1-3khz.

Additionally, I have seen argument that the headphone.com graphs are inaccurate over 1khz, so that would further confound the results.

 

[sejarzo]

One of the first things I noted when I put on the K601's is that they felt nothing at all like the K701's. The K601's were actually quite uncomfortable after a couple of minutes, when the K701's felt great and just got better in my 7-10 minute audition.

At some point last year, I looked at various photos of the two cans/pads to see what might be significantly different. The K601 pad appears to be of very consistent thickness around the entire circumference, while the K701 pad seems to be relatively thinner on one side versus the other (I can't recall which side that is, though!) I didn't think I had a "small head", but the earcups on the K601 are so large that they didn't "seal"....there was always a gap between my head and the pad, at a point sort of straight back of the bottom of my jaw--about straight down from the rear of my outer ear.

Back in the days of strictly closed cans, sealing them to one's head was necessary to get full bass response. If I push in toward the top of my HD600 earcups to produce a gap beneath my ear, the bass response definitely drops.

I don't know what HeadRoom's test protocol is with respect to fit issues--maybe they adjust positioning and/or clamping force to ensure that the entire circumference of the pad is sealed against the dummy head.

 

[sejarzo]

Quote:

Originally Posted by egokun /img/forum/go_quote.gif Judging from the curves, the AKGs do seem to have the bass, "objectively". .....:

Quote:

Originally Posted by ph0rk /img/forum/go_quote.gif .....the headphone.com curves are matched at 600 hz, not 1khz or 1-3khz. Additionally, I have seen argument that the headphone.com graphs are inaccurate over 1khz, so that would further confound the results.

The differences in the bass range are only about 1 dB or less--which is likely close to the differences between drivers in the same pair of cans. Also, if you use an EQ to boost those ranges only 1 dB, you'll the difference is rather slight, far less than what many of us find when listening to AKG's versus Senn's. To me, the bottom end was virtually non-existent on the K601's.

Also, if you look at the response at 600 Hz versus 1 kHz for these comparisons, there would be precious little difference should one frequency or the other be used as the match point.

It sure seems that there should be some way to create graph based on for perceived loudness, such as setting the input level with pink noise to be 85 dB, and then running the FR sweep.

 

[PFKMan23]

That comparison, which is of the 2 Senn and AKG cans I own (also own K1000 and PX100), makes sense to me why the Senns would have more bass.

 

[sejarzo]

Quote:

Originally Posted by PFKMan23 /img/forum/go_quote.gif That comparison, which is of the 2 Senn and AKG cans I own (also own K1000 and PX100), makes snese to me why the Senns would have more bass.

I'm confused.......that graph shows the K701 as having much more bass than the HD580 all the way down the frequency range.

Did you possibly mean to type "no sense" and it came out "snese"?

 

[PFKMan23]

To me it can make sense if you take into consideration the whole picture. And yes I corrected my previous post.

The 701s have a roll off that the 580s do not, which can influence how the music is presented (ie: when one portion has a roll off, the other portions can seem more prominent than they are). That said I'd like to see how other tools measure these headphones.

 

[sejarzo]

Quote:

Originally Posted by egokun /img/forum/go_quote.gif ..... The curious thing is that, after I switched the tri-flanges with the Shure black olives on the UM2, this notoriously all-bass IEM suddenly changed its sound signature to something not so different from the K701....

Just recently, I found that the guy who ran the hi-fi shop across the street from the Purdue campus, where I bought all my gear during college and for a long time thereafter, had taken a role at Klipsch as director of education. We exchanged a few emails re old friends and such, and in one I mentioned that I just wasn't an IEM guy.....none of the seals ever seemed to work for me for more than a few minutes, and even those few minutes were always somewhat uncomfortable......he replied:

"One of the things our research with the IU (go
boilers) audiology department revealed is that
the ear canal is not round in crossection though
all the ear gels up to now have been round. So you
either get a bad seal or if you push in far
enough, you get discomfort. The Klipsch designs
are all oval; offered in numerous sizes and flange
options. This seems so simple but makes a big
difference. "

Interesting, eh?

 

[number1sixerfan]

"In theory, there is no difference between theory and practice. But, in practice, there is."
- Jan L.A. van de Snepscheut

Imo, graphs are not always representative of what the case is in real life.

First, to have this argument, you must establish what you mean by "bass shy"(this, no one will agree on). The AKG k701 extends very low and has very detailed bass. However, the quantity of bass and bass impact is lacking in comparison to nearly every headphone in it's class/price range. (hd650, grado 325i, beyer dt990, sa5000, etc.) In contrast, a lot of times, phones that have more impact and quantities of bass lack the control and detail of the k701's bass. So there is a trade off. These are the things that a headroom graph can't explain to you.

Another thing people tend to forget is that after time with a can, you tend to get used to their signature. So in fact, if a can seems bass shy with early use, eventually the bass may be sufficient. Many call it burn in(which it can be), when really sometimes it is simply them getting acclimated to the sound.

 

[SonicDawg]

the human mind is a powerful thing..

 

[sejarzo]

Quote:

Originally Posted by PFKMan23 /img/forum/go_quote.gif To me it can make sense if you take into consideration the whole picture. And yes I corrected my previous post. The 701s have a roll off that the 580s do not, which can influence how the music is presented (ie: when one portion has a roll off, the other portions can seem more prominent than they are). That said I'd like to see how other tools measure these headphones.

I'm seriously not getting something here...and definitely not trying to hassle you, but to simply understand your point....at what frequency range in that graph does the K701 have a roll-off that isn't present in the Senn's that would make them perceived as "bass-shy"?

The only point that I can see is at 12 kHz, which is way up there, and the Senns have a similar dip at 16 kHz.....neither of which should have an impact on perception of the low end, and up in the really airy part of the frequency range (where my 50 year old ears have got to be deficient!

)

 

[sejarzo]

Quote:

Originally Posted by number1sixerfan /img/forum/go_quote.gif First, to have this argument, you must establish what you mean by "bass shy"(this, no one will agree on). The AKG k701 extends very low and has very detailed bass. However, the quantity of bass and bass impact is lacking in comparison to nearly every headphone in it's class/price range.

But when you say "quantity of bass...is lacking", that would mean there should be a measurable reduction in amplitude response in the bass range....and that's exactly what is being measured in the frequency sweep!

 

[SonicDawg]

Quote:

Originally Posted by sejarzo /img/forum/go_quote.gif I'm seriously not getting something here...and definitely not trying to hassle you, but to simply understand your point....at what frequency range in that graph does the K701 have a roll-off that isn't present in the Senn's that would make them perceived as "bass-shy"? The only point that I can see is at 12 kHz, which is way up there, and the Senns have a similar dip at 16 kHz.....neither of which should have an impact on perception of the low end, and up in the really airy part of the frequency range (where my 50 year old ears have got to be deficient! )

Look at the 701 vs 580 graph again. The lower end of the 580s roll off at the lowest side, thus accentuating the midbass or the perceived bassiness.