Phiaton

[spritzer]

I thought you guys didn't care about frequency response curves? I did one for an R10 (since deleted sorry) but I didn't post it because people would have gone nuts telling me I did stuff wrong

I don't but that was meant as a joke.

[Dusty Chalk]

It's not because we assume you did stuff wrong, it's because we're not warm and fuzzy that you don't. I mean, don't take that as a permanent criticism -- we realize you're still "cutting your teeth" when it comes to taking headphone measurements. When your measurements start reflecting our experiences, then we'll start putting stock in them. Maybe (some people will never). Of course, I remember seeing the measurements of a pair of ...what was it, the AKG K1000's? And they looked like crap.

You know, Headroom have their own faraday cage/sound isolation room. I'm not sure what type of measurement microphones they use, though. And you do realize "measurement microphones" are a special class of microphone, and that you can't just use any old microphone, right?

[swt61]

And you do realize "measurement microphones" are a special class of microphone, and that you can't just use any old microphone, right?

Shit! Back to the drawing board.

[spritzer]

Since were on the subject... a point of comparison which lists the mic's used

[Dreadhead]

It's not because we assume you did stuff wrong, it's because we're not warm and fuzzy that you don't. I mean, don't take that as a permanent criticism -- we realize you're still "cutting your teeth" when it comes to taking headphone measurements. When your measurements start reflecting our experiences, then we'll start putting stock in them. Maybe (some people will never). Of course, I remember seeing the measurements of a pair of ...what was it, the AKG K1000's? And they looked like crap.

You know, Headroom have their own faraday cage/sound isolation room. I'm not sure what type of measurement microphones they use, though. And you do realize "measurement microphones" are a special class of microphone, and that you can't just use any old microphone, right?

WTF does a Faraday cage have to do with taking sound measurements? May I ask were the electrons or electric field come from? There are such things as measurement mics? really?

Headroom uses a "Head Acoustics Artificial Head Measurement System" which can be found here (HEAD acoustics - Telecom Division - Binaural Recording Systems - Artificial Head Measurement System HMS II.4 - Overview) though I'm not sure which model in particular they own. I assume they use the anechoic chamber so they can measure the isolation which is not a particular concern of mine and so as to not have reflections effect the results. Their measurements make even less sense than mine considering that the isolation (a physical property) changes with balancing, this likely points to different positioning on the head which is more of an issue that some would like to believe.

I have an ECM8000 measurement mic (as stated many times previously), which is admittedly a cheaper measurement mic but I got the calibration curve that was professionally done for one of them at a lab. Admittedly I could do a lot better as far as a measurement mic goes but for the money it does the trick. I considered buying a coupler and still might but considering I could build one of of structural foam for free I decided to do that for now. I've seen neumann and other heads go on the second hand market but I'd need a whole lot more of a reason (such as a business like Headroom) before I invest in one since they are several hundred dollars. As far as an chamber I'll stick with doing it in a very quiet room since it's a whole lot cheaper

Cheers.

[Dreadhead]

Since were on the subject... a point of comparison which lists the mic's used

nice. That is a all out analog measurement done with a paper plotter. SCHWEET

[Dreadhead]

nice. That is a all out analog measurement done with a paper plotter. SCHWEET

Looks Like I could rent a that pair for a month for 310

BRUEL & KJAER 4153 - For Sale at Used-Line

tempting.... not this month though.

[postjack]

I've got a big playlist of songs that I want to do detailed comparisons on, but I'm thinking at this point that there really isn't a whole lot to redeem the cans.. we'll see though.

The GS1000 had additive synergy with open mic, AUD type live concert recordings, due to such recordings naturally being rolled off up top and bass heavy down on the bottom. The drums really sounded like live drums. That and well-mastered electronic music with a lot of low end heft. But it was so good with these types of music that I kept mine for some time.

Actually it was also good for some low volume jazz and classical.

[Dusty Chalk]

WTF does a Faraday cage have to do with taking sound measurements? May I ask were the electrons or electric field come from?

Latter question first: this is the 21st century, you want a list? Cell phones, refrigerators, microwaves, wireless networks, power lines, non-FCC-compliant devices, barely-FCC-compliant devices, fully-FCC-compliant devices that still emit crap, model train sets, RC helicopters, Roombas, solar flares...I could go on and on. You unplug everything in your house, and it's still got the power and phone circuits inside, and who knows what outside.

Former question: you're familiar with the concept of amplification, neh? EM waves crossing with EM waves, etc.? I guarantee you the noise floor of the electronics (as opposed to the ambient noise floor, which is what the anechoic chamber is for) will be lower (and the background blacker, blah blah blah) in a Faraday cage, being my point.

You've ever been to a concert where the guitarist's amp picks up a radio station? Same principle.

[Torpedo]

I thought you guys didn't care about frequency response curves? I did one for an R10 (since deleted sorry) but I didn't post it because people would have gone nuts telling me I did stuff wrong

I think the R10 measure far from flat, but for sure not in the same crappy way that those Phart-on do.

[Dreadhead]

Latter question first: this is the 21st century, you want a list? Cell phones, refrigerators, microwaves, wireless networks, power lines, non-FCC-compliant devices, barely-FCC-compliant devices, fully-FCC-compliant devices that still emit crap, model train sets, RC helicopters, Roombas, solar flares...I could go on and on. You unplug everything in your house, and it's still got the power and phone circuits inside, and who knows what outside.

Former question: you're familiar with the concept of amplification, neh? EM waves crossing with EM waves, etc.? I guarantee you the noise floor of the electronics (as opposed to the ambient noise floor, which is what the anechoic chamber is for) will be lower (and the background blacker, blah blah blah) in a Faraday cage, being my point.

You've ever been to a concert where the guitarist's amp picks up a radio station? Same principle.

Better pull out your tin foil hat... I mean faraday cage lol

[Dreadhead]

I think the R10 measure far from flat, but for sure not in the same crappy way that those Phart-on do.

That I will entirely agree with you about

[Dusty Chalk]

Better pull out your tin foil hat... I mean faraday cage lol

Well, if one goes through such efforts as to perform the measuring in an anechoic chamber to reduce the ambient noise floor, why wouldn't one go through the same lengths to reduce the electronic noise floor?

We're talking about Headroom here -- they're putting their measurements out there so that they are known worldwide as the place to go to for headphone information. I think it's perfectly legitimate, given the context.

The conversation stemmed from you complaining about why Headroom's measurements were taken (somewhat) seriously (by some) and yours were not. Now you know -- just answering the question.

[Torpedo]

I can agree that Dreadhead's measurements may not be kosher and his measurements system is "clearly improvable", however, as far as he had measured a few phones and we could take his results under the scope of comparison terms to other well known phones, having cans measured won't harm. IMO if he posted his graphs of the R10 and we could compare them to his measurements of HD6xx, K701 and other popular phones, it'd be interesting to me so far.

[Dreadhead]

Well, if one goes through such efforts as to perform the measuring in an anechoic chamber to reduce the ambient noise floor, why wouldn't one go through the same lengths to reduce the electronic noise floor?

We're talking about Headroom here -- they're putting their measurements out there so that they are known worldwide as the place to go to for headphone information. I think it's perfectly legitimate, given the context.

The conversation stemmed from you complaining about why Headroom's measurements were taken (somewhat) seriously (by some) and yours were not. Now you know -- just answering the question.

I actually wasn't saying that mine weren't taken seriously. I couldn't really care less that my measurements aren't being taken seriously by Head-Case. I mostly just responded to you so others wouldn't spout what you were saying.

My question to you is that do you realize that the steel grounded cage around their amps is Faraday cage so that's not going to lower anything unless they are already in a region of very high EM. I've done measurements measuring microvolts out of very sensitive quantum mechanics experiments and guess what no faraday cage.

If only I would have used the cage then I'd have a nobel now.... damn

As far as headroom and their measurements as I've said before their experiments show physical impossibilities and varying noise floors which point pretty handily to serious experimental design problems. I always used to trust their measurements but I do so less now.

[Dreadhead]

I can agree that Dreadhead's measurements may not be kosher and his measurements system is "clearly improvable", however, as far as he had measured a few phones and we could take his results under the scope of comparison terms to other well known phones, having cans measured won't harm. IMO if he posted his graphs of the R10 and we could compare them to his measurements of HD6xx, K701 and other popular phones, it'd be interesting to me so far.

My measurement setup is kosher for any delta (comparison) measurement as far as I'm concerned. The fidelity of the measurement can certainly be improved with a better mic or an artificial ear but the experimental design as it stands is fine for the purpose. I have done way to many experiments in my life to not at least know how to make a control set and do repeatability tests etc.

As I said before I deleted the graphs of the r10 months ago when I was cleaning out my DEQ. By my recollection they were a bass light pair had an exceedingly enhanced mid-range and rolled off highs and lows.

[Torpedo]

My measurement setup is kosher for any delta (comparison) measurement as far as I'm concerned. The fidelity of the measurement can certainly be improved with a better mic or an artificial ear but the experimental design as it stands is fine for the purpose. I have done way to many experiments in my life to not at least know how to make a control set and do repeatability tests etc.

As I said before I deleted the graphs of the r10 months ago when I was cleaning out my DEQ. By my recollection they were a bass light pair had an exceedingly enhanced mid-range and rolled off highs and lows.

That's it, having some measurements under the scope of being comparable to other phones and being repeatable, is quite useful.

Do you remember at what frequency started the treble and bass roll-off? Do you remember how much clamping pressure did you use between the can and the dummy ear? Did you perform several measurements at different clamping pressures? Apart from amplification, I've found that the bass light R10 change a lot their frequency response depending on placement and above all, the ear-driver distance. Their sound changes drastically between used pads and a set of new ones.

[Dreadhead]

That's it, having some measurements under the scope of being comparable to other phones and being repeatable, is quite useful.

Do you remember at what frequency started the treble and bass roll-off? Do you remember how much clamping pressure did you use between the can and the dummy ear? Did you perform several measurements at different clamping pressures? Apart from amplification, I've found that the bass light R10 change a lot their frequency response depending on placement and above all, the ear-driver distance. Their sound changes drastically between used pads and a set of new ones.

I'm sorry I can't remember where the roll off occurred but it was pretty fast and was over 10db by 20hz. I would guess it started at about 80? Really though I would not trust that number at all.

I did not change the clamping pressure but I did move them around relative to the measurement mic and repeat an that did not make much difference. Because my "dummy head" is a flat bloc of foam the transducer to mic distance didn't change much. I would be interested to check to see if the seal is better with new pads and that's why they sound different. My limited experimentation with this is that if the seal isn't perfect the results can change a lot.

[Torpedo]

You don't get perfect seal with the R10 for the quite low clamping pressure of the headband. For my head and ears, for other people this can be different, of course.

New pads are thicker and place the driver about 1/4" further from the ear canal entrance than aged pads. That makes a difference in the subjectively perceived roll-off in the bass. On new pads I need to add manually some extra pressure to get a decent bass response. Without that extra pressure I think the roll-off starts at about 120Hz (for male vocal formants) and for sure is at about 10 or 15 dB below at 40Hz. With that extra pressure, so new pads get flatter and more like the used ones. In this case I think the roll off in bass starts at about 70-80dB and probably at 40Hz you are between -6 to -10dB.

I'm not sure about the treble roll-off. My subjective impression is that the cans must have some enhancement around 8KHz compared to the high midrante at 1KHz. Above 12-15KHz they're probably rolled off, but nothing that annoys me. In fact I tend to prefer transducers with some roll-off above 12-15 KHz than the ones being flat or enhanced at those frequencies.

I am very interested in correlating these findings with actual measurements, but looks like I'll have to wait for my technician friend having the spare time to do so

[Dreadhead]

I am very interested in correlating these findings with actual measurements, but looks like I'll have to wait for my technician friend having the spare time to do so

yup since you actually own the phones. I unfortunately do not or I would do the measurements with my setup. I think your observations sit pretty well with what I measured but again this is a foggy recollection. Sort of annoyed I deleted it now. As we have already discussed your buddy's mic and ear are nicer than my setup anyway.

I use a pair of rubber bands to apply the clamping pressure in my case which is not ideal but does work. I'm thinking about that artificial ear though, that would settle these issues pretty much but is still hard to justify when I will likely just settle down to two different or even one pair of headphones in the next year.

[Dusty Chalk]

My question to you is that do you realize that the steel grounded cage around their amps is Faraday cage so that's not going to lower anything unless they are already in a region of very high EM. I've done measurements measuring microvolts out of very sensitive quantum mechanics experiments and guess what no faraday cage.

I'm not talking from the amps, I'm talking to the amps. And not all amps have Faraday cages built into/around them -- not all are grounded, not all are steel, etc.

I mostly just responded to you so others wouldn't spout what you were saying.

Yeah, well, good luck with that. I wasn't the first person to say it, and I won't be the last.