arnaud

Actually, frankly speaking the visual appearance can really play tricks on people's mind without them even realizing, like the correlation between the size of a speaker / transducer and the expectation of low frequency extent / presence. It's far fetched but I would not be surprised people unconsciously associate the modern lines of a design like HD800 and the precision finish to some expectation of precise possibly even clinical sound... We've also seen headphone lines being created with essentially the same driver and housing dimensions but a gradation in materials (e.g. ugly plastic vs. nice exotic wood). Regardless of the sound, I bet many if not most will have a preconception toward the wooden headphone sounding better... How is that related to the 009? Well, the finish is resolutely more high-end in comparison to the Omega 2. It's really stupid but I am pretty sure it affected my judgement, even if it's minor (the edition 10 looked marvelous but I felt it sounded like s...t after 10 seconds so fortunately there are limits to the effect ).

Very little, I was placing furnitures while waiting for your impressions. Will stop there!

I don't mean to get you on your horses. I was simply suggesting that sometimes one can draw the wrong conclusions from limited observations. As you know, measurements are hyper sensitive to headphone placement so there's little way to guarantee this was not the main factor in what you observed. Furthermore, since you're doing sine sweep, there's indeed no way to pull these room reflections from the measurement as is possible with an MLS test. The room influence and proportion of direct to reflected field has been key part of my work for the past decade so I am starting to get a feel for it...

Haha, yes that is probably a very safe statement. Looking at inner fidelity website, the RS-1 isn't likely to fare much better than the RS-80 I am afraid: http://www.innerfidelity.com/images/GradoRS1.pdf

I still expect the room feedback to be down in the noise floor though but I guess better safe than sorry. As for non-linearity of the driver due to impulse test, that'd be a worry if it is a real issue too (because you're basically listening to 99% transient music). Unless the instant power is way beyond the operation range of the driver, you really shouldn't see such non-linearity.

Indeed, it makes no sense price wise but higher end Grados often don't fare much better as far as these nasty peaks are concerned. The thing is, these resonances are likely acoustic ones from the chamber. Be it nasty plastic of the SR80 or previous wood from the RS-1, they'll still be there for a given shape of enclosure considering that Grado uses the same pads (same acoustic absorption) across the range. I'd be happy to compare if one sends me the impulse response data. 80USD is not much in today's world of 1000+USD headphones. But still, it's a pretty darn awful response (and sounds the same to my ears).

Since Purrin was kind enough to send me his raw impulse response data, I investigated this further but reprocessing the data using Matlab... It's confirmed for Purrin's data: the reflection from the room (at 7 to 9ms) is pretty much in the noise floor (50dB down or so from the peak response) and has very little impact on the response: Impulse response: Energy time curve: Frequency response, including or not the first room reflections: Then, just for kicks, here is a comparison of the HD800 and SR-80 which is, how to say, enlightening . The Grado headphone sure is lively in the upper midrange! Some manufacturers are lucky no-one in the industry is publishing comparative CSD graphs ... yet ... Impulse response: Frequency response: Spectral Decay - waterfall (30dB range): Spectral decay - contour plot (30dB range): Additional results to be posted in the original thread...

Well, actually they sound like an ultrasone on a bad day. But in my case, I had to justify the expense and praise it to the moon... Sorry about that... I thought i read someone on HF from the US who received it though? The end of the tunnel must be near!

I shouldn't have just stated the increase in resolution, it is so much more than that, in particular impact, imaging, and bass extension + control. But anyhow, as for waiting for people impressions whom you trust, I would do the same if I was in your shoes given the very very steep price of the 009... For all we know, I might be going death, hence insensitive to 4kHz peak so you're better off waiting ;o). If that's any reassurance though, I am really not a fan of artificial brightness usually (hated most of Focal's speakers in the past and to a lower extent some higher end B&W speakers until the most recent diamond series).

Humm, it's hard to believe the room effects can be so significant unless you're doing the measurements in a room the size of a shoebox or in a reverberant chamber. At low frequency, you're just measuring evanescent waves (bass sounds are only heard in the near acoustic field but don't propagate in the room). And for higher frequencies, the direct field from the transducers is likely several over orders of magnitude higher than waves bouncing off your walls. On the other hand, acoustic reflections from the test apparatus are very real as mentioned by purrin. In your case, didn't you get better result simply because of the averaging? i.e. the response of the transducers at a single mic position get very sensitive to slight variations in how the headphone is positioned as frequency goes up so every time you moved the headphone around, you were simply slightly perturbing the test setup and your average response is smoother as a result.

Absolutely brilliant! I replied there and won't double post here as I got flamed before for that but I really wanted to see such test data at the time I was tinkling with the mod! Would really like to hear how you are doing the measurements! cheers, arnaud

I seem to also handle a peak in this region better than if occuring higher up. But I also agree with you that some may have difficult time adjusting to the 009 if they feel all is good in their current Omega 2 system. For instance, I assume you got a BHSE with O2mkI or something similar? I did not get exposed to this as my O2 (007A) may already be flawed compared to the previous gen. and I was driving it with what is considered a terrible amp in stock form (727A). So, I guess, there was significant room for improvement (although that was already better than any dynamic gear I had every owned) and the 009 took my system to a whole new level, a different league. Of course, this extra resolution (I really don't believe this all is just due to a change in the voicing) came at the cost of providing proper recordings, but it's really worth it in my book.

This makes a lot of sense, and correlates with my subjective impressions. Maybe these graphs should be interpreted with care. For instance, they may have been taken by someone wearing in-ear mics and not equalized. Then, the 4kHz peak would just be what you said: visualization of the outer ear resonance effect. Now, they indeed can't be perfectly balanced for anyone's ear but that's not news in the world of headphones. The lack of equalization would also explain the large drops at 8kHz and such I assume. So, in my view, these graphs only tell us the 009 is brighter than 007A in the 4kHz zone. I have similar issue to Gu_Sensei with bright / harsh recordings, but other than that I feel the 009 is the more neutral of the two when comparing to my 007A. At least I don't feel any artificial brightness, like happens with the peaks in 8kHz range of HD800. Or ... it could be my ears are shot from overexposure to loud sounds (i.e. 20dB sensitivity drop in the 4kHz zone), that'd be a worry . Edit: trying to decipher the thread where the measurements were posted -> the person who measured the 009 said that the differences between left and right ears of the 009 are likely due to non-calibrated mics / changes in ear shape and mic location. So, it does seem like an individual measurement on someone's head while wearing some of these (possibly borderline accurate) in-ear tiny mics.

I confirm that there appears to be stock at the local dealers. At least, Audio Union had 2 units ready to ship as of last week end. It looks like Stax is being very very cautious with international shipments, which is understandable given the bad publicity and costs of shipping.

I keep listening to samples of this new release but however hard I try, I can't see myself enjoying the recording apart from maybe a couple of tunes like Ghost. I guess it's all in the listening all the album all the way through but I still don't feel like spending 15 bucks for this album. I have been a fan of radiohead from the beginning, saw them live around '96 in a small concert hall in Paris (maybe best concert I have ever been to). I also really find in rainbows awesome (just listening to Weird Fishes through the SR009 now, oh my ....... better be careful, I could listen to this at eardrum splitting levels ). I also like kid a / amnesiac era a lot as well. But somehow, this time around, I don't see myself digging this new recording.

What is this something else if not inappropriate to ask? Magnesium, carbon fibers?

I believe the main driver for using aluminum is the looks of the finished product (fine machining) more than anything else. In particular, although it's true that an aluminum part has much more rigidity than most plastics of same shape, hence resonances pushed higher up, they're also much less damped than those of any plastic, which makes aluminum potentially less desirable... In the current application however, I fail to imagine how the little inertial forces of the moving diaphragm can noticably excite mechanical resonances in the earcups. In comparison to the motion and radiation of the driver itself, it's likely negligeable.

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.

It's been several weeks of ownership for me, and my opinion of the 009 has not changed a bit even now that the new toy syndrome phase is over. I could be wrong but I really don't believe the sense of resolution / details comes exclusively from the brighter nature of the phone relative to my O2 mk2. The best way I can express it is in the texture of cymbal sounds. This is something shocking when you hear drums live and the 009 is the closest I've ever heard. Fake treble boost can't help to resolve cymbals. You need speed, extension, and so on. Now, I don't have the chance to possess a bhse or diy T2 like some (most?) of you, but the experience is already sublime out of a stock 727, WHEN fed with quality recording and source...

Maybe this is the paper you're referring to? http://smyth-research.com/articles_files/SVSAES.pdf I just read through it and would very much like to hear the system one day. I wonder though if - for multi-channel audio or movie soundtrack - you would not be better off with 7 virtual ideal point sources without speaker nor room coloration? In which case the "only" thing you really need is a set of personalized HRIRs which could be recorded in a reasonably dead sounding space. The loudspeaker response and residual room response would be equalized out of the HRTF because you'd perform both a measurement with in-ear mics and a measurement with a microphone at the head position. Actually, for that matter, if you're able to get your personalized HRTFs for just stereo speaker positions (+/- 30 deg), then you could also apply these filters to your audio library, maybe it could even be done realtime with nowadays computers so you don't have to store your library twice with / without auralization filters. Nowehere near as practical as the Smyth system but nevertheless a way to get a feel for the power of this technology without having to spend so much money at first. The other thing I thought surprising in the article is the mention that HRTFs interpolation is possible using only 2 angles (such as 0 and 30 for some interpolation at each angle in this range) without perceived loss in fidelity. I thought the brain was super-sensitive to very slight changes in head orientation and that it wasn't just a question of inter-aural time delay. So, I expected you litterally needed HRTFs with 1 degree step or so to perform some head tracking! That's pretty neat if not.

You've found a good reason to sit patiently for another couple of months, that's good for your sanity . In the eventuality there was a problem when you receive yours though, it's not like shipping back a 70+ lbs amplifier. Would cost at most 100USD to ship it back insured and take no more than 3 days... In regards to 5kUSD you'll have spent on it, it's peanuts... Turnaround would also probably faster than going through a dealer and notoriously proactive distributor ... Just saying, it's not like you got a choice anyhow... arnaud

Ahhhh... I am so not confident I can do the mod by myself... I have done soldering in the past while working for a french audio maker though, but it's a looong time ago... The mods sounds like a major step in the right direction though, that would be just perfect while I must pace myself and wait for funds to cover the sr009 purchase! It does not sound like too difficult a job though, ....

Went to the spring headphone festival from fujiya avic today in Tokyo. I could drool again on the sr009 (marantz cdp, 727a amp). Quickly compared against the o2mk2 listening to a drum xrcd recording, I really really need to start saving... It's so much more lively/dynamic/correct sounding than the o2mk2, it doesn't take 5 seconds to realize! From discussion with the Stax staff, it's only 1dB more sensitive than the o2 but it feels more like 2-3 dB, probably due to the change in tonal balance. I asked about potential new amp to pair with the sr-009, and something will indeed be released at some point, but certainly not this year and probably not next year either. Waiting in line for a BHSE from Justin doesn't sound like a bad option suddenly! From what I understood, Stax isn't even decided on which route to go (ss or valve) as various markets have differing preferences and Stax will need to settle...

I forgot about this one, I guess I did not want to mess extensively with the headphone. I am guess I should then bend it so as to increase clamping force and ensure the seal? I do have a small head (I should add "physically speaking" else I might be quickly corrected by some here ). Humm, I must have got myself one of the last sets for sales in Japan in the SZ2 series and I wasn't aware of so many changes in the "mk2.5" version (a new driver!?). Anyhow, the way I see it, if I want to bring my stax experience to the next level, the next move is 349,000 yen away .

I believe I have one of the last mk2 series being in the SZ2-1600 range (purchased new in summer of 2010). I did your spring mod but did not go all the way with blocking of the ports. The bass does sound a bit uncontrolled at times through my stock 727A, yet it cleared gets better with ensuring a good fit (I must take off my glasses for instance to make the seal). You'll say: so what, this is well known. But the interesting thing for me is that my way to know the fit is right is to systematically check that it makes some kind of farting sound when pushing against the ear cup toward my ear. It's a weak fart, nowhere near as obvious as I remember from mkI series, but really you can hear something going on. I've posted pics of my unit before and I believe you or someone here did see the ports.