[captian73]

What’s the point in graphs when you have me with good (o.k.) hearing, my dad who where's a hearing aid, and my brother-in-law who is profoundly deaf and communicates via sign language?

 

[Shike]

Quote:

Originally Posted by jynweythek /img/forum/go_quote.gif Looks very different. I don't know if the SR60 graph is accurate (never listened to an SR60). But the V6 graph, at least, does seem quite accurate.

The problem is we don't know how the owner of the site measures phones and what equipment they use to do it. If we didn't have to worry about the HRTFs life would be just a bit easier.

 

[miscreant]

Learning Center - About Headphone Measurements | HeadRoom Audio

 

[Shike]

Quote:

Originally Posted by miscreant /img/forum/go_quote.gif Learning Center - About Headphone Measurements | HeadRoom Audio

Was this aimed at me? I was referring to the Japanese site . . .

 

[xnor]

Also keep in mind that just relying on headroom's graphs isn't the best idea since they're using it as marketing instrument.

 

[miscreant]

Quote:

Originally Posted by Shike /img/forum/go_quote.gif Was this aimed at me? I was referring to the Japanese site . . .

no. i meant that there are more graphs than eq graphs.
who buys headphones looking at graphs anyway?

 

[Shike]

Quote:

Originally Posted by xnor /img/forum/go_quote.gif Also keep in mind that just relying on headroom's graphs isn't the best idea since they're using it as marketing instrument.

I don't know why you're so concerned. Headroom's a good company, and people tend to buy a headphone they want despite measurable "flaws" so to speak. As a marketing tool it's probably weaker than the "what we think" section.

Quote:

Originally Posted by miscreant /img/forum/go_quote.gif no. i meant that there are more graphs than eq graphs. who buys headphones looking at graphs anyway?

Those that value empirically measured accuracy like myself.

 

[moonshake]

By the way, DAC and / or / + AMP = totally change freq spectrum

 

[xnor]

Quote:

Originally Posted by Shike /img/forum/go_quote.gif I don't know why you're so concerned. Headroom's a good company, and people tend to buy a headphone they want despite measurable "flaws" so to speak. As a marketing tool it's probably weaker than the "what we think" section.

I don't deny that headroom's a good company. What I'm saying is that you cannot trust those measurements blindly.
Over the years they changed the measurement methods and graphs changed, afaik, graphs also changed after repeating the same measurements (problems with seal/fit of hp on dummy head etc.)
Also, I doubt the usefulness of those square wave measurements. CSD and distortion over the whole frequency range would be more useful.
And I also don't like the smoothing applied to the FR graphs (even raw ones).

Besides, I still don't know what amp they used exactly (and what its output impedance is).

.. enough talk about concerns.

Most of their measurements I've taken a closer look at are comparable to other measurements I've found on the net, but there are exceptions.

So again, I'm just saying that you shouldn't rely on a single measurement blindly - look at the raw/compensated ones, try to find others to compare to. HeadRoom's great.

Quote:

Originally Posted by miscreant /img/forum/go_quote.gif who buys headphones looking at graphs anyway?

I'm not buying because of a certain graph, but graphs can help you make decisions.

 

[Shike]

Quote:

Originally Posted by xnor /img/forum/go_quote.gif Also, I doubt the usefulness of those square wave measurements.

It's a good way of measuring mechanical damping, and is even used in some speaker tests. I don't know why you would question the usefulness of being able to track a signal properly.

Quote:

CSD and distortion over the whole frequency range would be more useful. And I also don't like the smoothing applied to the FR graphs (even raw ones).

CSD is definitely more beneficial, but the distortion (THD) over the range is already dismal (less than 1%). As for the smoothing you also have to consider the resolution of the measurements that allows them to do it.

Quote:

Besides, I still don't know what amp they used exactly (and what its output impedance is).

I suggest you read the section on Headwize here titled "Is an amplifier's damping factor important to headphone performance?"

I have no doubt that headroom used sufficient equipment.

PS:

As for oddities between graphs . . . they can exist based on how the measurements are done. However, don't forget that each company works within specific tolerances in manufacturing too so some differences are bound to exist.

 

[Bradan]

Quote:

I don't know why you're so concerned. Headroom's a good company, and people tend to buy a headphone they want despite measurable "flaws" so to speak. As a marketing tool it's probably weaker than the "what we think" section. Those that value empirically measured accuracy like myself.

I agree, the placebo effect and marketing are strong in the hi-fi community.

Whoever said square wave means nothing is very wrong. As far as I know, it's the low-end that we hear phase-errors in, not the high end, as contrary to the popular notion.

This is why they have 50hz/500hz squarewave graphs.

Take a look at this:

This is what comes out of a perfectly flat boxwave, kind of surprising isn't it?

1st SE310
2nd AH-D2000
3rd HD800
4th Skullkandy Hesh

IEMs almost always win this test, and from my experience, usually produce the "tighest" bass, maybe not so musical because of the accurate nature of them, but hey.

It somehow always amuses me how quickly people will dismiss the only objective means of assessment we have to judge headphones with.

 

[jcx]

headphone FR graphs should be repeatable and accurate below ~1KHz where the eardrum to diaphragm distance is a small fraction of the sound wavelength


Quote:

Originally Posted by moonshake /img/forum/go_quote.gif By the way, DAC and / or / + AMP = totally change freq spectrum

if they do you should want your money back - or should have spent it on a equalizer and a good, accurate DAC/AMP combo

Dacs in general don't "editorialize" - accuracy is their reason for existance and is the achieved fact - just look a RMAA loop back tests

Amps that have audible frequency response variations are usually considered flawed - too small output coupling C giving a high pass filter in the bass region with lo Z cans is common with portables and some tube amps

Amplifier output impedance is assumed to be low by most headphone designers - but there is a mostly ignored DIN standard for 100 Ohm output resistance

Amps with low output impedance and flat frequency response are preferred since you can always add your own resistor to passively eq your headphones if you believe the designer intended higer Z drive


I suspect a large fraction of the reported subjective frequency response varitions in amps and DACs in these forums is likely the result of not level matching and blind testing - Fletcher-Munson effect says you will perceive differing frequency balance at differing SPL and DBT says 0.1 dB level differences can be noticed - but such small differences are not identified as a loudness difference

 

[xnor]

Quote:

Originally Posted by Shike /img/forum/go_quote.gif It's a good way of measuring mechanical damping, and is even used in some speaker tests. I don't know why you would question the usefulness of being able to track a signal properly.

I understand that it's not totally useless (also didn't say that), but who cares about mechanical damping in headphones?

Please compare the HD800, PX100 and K601 in terms of mechanical damping with both 50 and 500 Hz square waves. What is the best and why?
For me they seem to be on par, but maybe I'm just blind or don't know what to look for...

@Bradan:
Take the same headphones (as you posted) and compare them using the normal FR.
Now rank them again based on how flat their response at the lower end is.

another example: compare DT700 and HD800

... so I think that you're looking at the wrong thing.

That's why I said that those square waves are not very useful - for me at least.


Quote:

Originally Posted by Bradan /img/forum/go_quote.gif Whoever said square wave means nothing is very wrong. As far as I know, it's the low-end that we hear phase-errors in, not the high end, as contrary to the popular notion.

I didn't.
.. and these phase-errors can be found in square wave graphs...?


Quote:

CSD is definitely more beneficial, but the distortion (THD) over the range is already dismal (less than 1%).

I've seen measurements of HPs at 80 dB SPL with ~3% THD.
Let's take the "new" HD238 for example, people claim that they can hear bass distortion.. I'd love to see that on paper.

Quote:

As for the smoothing you also have to consider the resolution of the measurements that allows them to do it.

The resolution of the measurements is much, much higher than what they show us, I guess.


Quote:

I have no doubt that headroom used sufficient equipment.

Me too, but you never know..

Have you read that faq entry? Nothing new besides this:

"The motional impedance of headphone transducers varies very little (or should vary very little - someone can always do it wrong!) with frequency, so the source impedance can be high with no ill effect."

rotflmao. Is this a joke?


Quote:

As for oddities between graphs . . . they can exist based on how the measurements are done. However, don't forget that each company works within specific tolerances in manufacturing too so some differences are bound to exist.

I know. That's actually a big problem. Ordered a CAL! a while ago (for modding) and the right side produced over 3 dB more bass (~60 Hz).
phhhh..

 

[xnor]

Quote:

Originally Posted by Bradan /img/forum/go_quote.gif IEMs almost always win this test, and from my experience, usually produce the "tighest" bass, maybe not so musical because of the accurate nature of them, but hey.

IEMs maybe, but full sized-headphones?
Tight bass and a good looking 50 Hz square wave are mutually exclusive!

 

[nhancakes]

Quote:

Originally Posted by stang /img/forum/go_quote.gif Lol, according to the graph, it should be a lot better.

I'm not sure what you interpreted from the graph that lead to the idea the 900 "should be a lot better".