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arnaud last won the day on August 30 2011

arnaud had the most liked content!

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About arnaud

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  • Birthday 01/01/1975

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  • Occupation
    Acoustic engineer
  • Hobbies
  • Headphones
    Stax SR-009 & SR-007mk1 (70xxx), Sony XBA-3
  • Headphone Amps
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    Yamamoto YDA-1, iphone

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  1. arnaud

    Kaldas Research

    Hi Aumkar, This is an interesting development and I am curious about how you came up with some of the design aspects. For instance, we can see that the open back baffle is quite deep and has non symmetric shape. Does this measurably affect the response on your kemar? Also, my recollection of 009 measurements is that is has ~80Hz resonance frequency loaded (~150Hz in free air) with a non-ported design. How about your prototype? From the measurements you published, it looks more like a ported design with ~45Hz resonance frequency? I'd be keen on making acoustic simulation of the housing + ear pads if you are willing to share this information, cheers, arnaud
  2. arnaud

    The Headcase Stax thread

    I don’t have much to add to hugo’s post, agree on the findings except perhaps sounstage which felt a bit more closed in on the 009S compared to 009. I also used my source (sony dap) HP out to drive the T8000 so it wasn’t ideal + noisy environment but I was pleasantly surprised by 009S. These days I am applying dig. EQ to my 009 to take the edge off the mids and boost the subbass a little so I did not think I’d get into the 009S. But what I listened to today was quite promising, the 009S improves on the 009 across the board and I could not find a drawback. It sounds cleaner, fuller body, more natural mids, looses that tendency of 009 to sound thin / agressive at high volume levels and does not loose any treble extension or resolution. I think this one is going to be popular with the mafia given the number of 007 fans and 009 haters ;-). Design wise, besides the official blurb on housing, stators and grill, the pads felt definitely stiffer than the 009 and I bet part of the chances in voicing come from there (perhaps more so than the gold plating of the stators). The 009 really do sound cleaner than 009 from bass quality to transparency overall, the structural redesign of the grill and such may be more influential than I would have thought. It was good to see Sasaki-san there (apparently the head designer Suzuki-san is joining tomorrow) but the new generation of employees seem to be on top of the game already so I can only wish a bright year ahead for Stax. Besides talk on the 009S, Suzuki-san mentionned all D/A related designed are outsourced to edifier (the new portable dac amp fully is), the upcoming dac board addon for the t8000 also won’t come out of Japan (they stick to analog components design). Apart from that, Edifier still leaves Stax full autonomy today it seems.
  3. Interesting tear down, thank you Birgir! The driver is effectively sandwiched between the housing the baffle plate through these rubber gaskets, quite different from Stax hard fixation style. Also, the wire mesh of the stator seems very very fine, that's interesting because I bet the airflow resistivity is actually orders of magnitude higher than than traditional perforated stators (that present little airflow resistance contrary to the common belief these days...). That fine wire mesh, ignoring the mechanical aspect for now, must certainly add significant damping to the diaphragm. As for the price drop, it's hard to imagine the SR009S release had no influence on that ;-) arnaud
  4. arnaud

    The Headcase Stax thread

    The worse part is that these comments made me curious and... so basically, woo wes and earpods is all you need, the rest is to show off and, by the way, I am spending 50 grands on a headphone system where the tubes raise up when you turn the amp on, I am thus done with audio. Finally someone who got it, it was about time. Back to you gilmore, building those carbons with burger. arnaud
  5. arnaud

    The Headcase Stax thread

    This is what Suzuki-san was saying in his video I think: DC coupled not strictly because of the use of servo.
  6. arnaud

    The Headcase Stax thread

    Suzuki-san confirmed this was for dac or phono board when I talked to him at the show. You should have asked me that before, I would have brought it up! Also he confirmed the dedicated low voltage supply for the addon board. Jude got other things confirmed when he visited Stax office on Friday (such as power supply regulation), I hope to see some news posted in the HF thread at some point. I liked what I heard on brief listen when compared to stock 727 amp, it felt more significant than differences between other stax amps. Of course, this is to be taken with a pinch of salt given the short audition / show conditions etc... Oh, and it does look very nice in person, sand blast finish on the aluminum panels, reminiscent of the SR009. It's bigger than other stax amps but nothing compared to my BHSE, I can see people wanting this. Arnaud
  7. arnaud

    The Headcase Stax thread

    There you go, I stand corrected. Now, if I only knew what this servo regulates actually ;-).
  8. arnaud

    The Headcase Stax thread

    From the little I understood in the video, slot 4 is for addon that are still in developments. Suzuki-san (chief designer) specifically mentioned about DAC or equalizer (phono that is?). He also mentioned this line 4 slot has its own transformer / supply, independent from the rest of the circuit. He mentioned great attention had to be paid to shielding giving how closely spaced these components are and the mixture of low level signals (including upcoming slot 4 boards) and 60dB circuit (or 54dB I forgot). So, encaged toroidal, encaged inpu stage tubes, encaged slot 4 board... Seems like a big effort just to make this all fit in one box to limit manufacturing / shipping costs and all. Oh, another thing he mentioned which flew over my head is presence of a servo (world first for stax) to make sure the amp operates within spec from cold start. Otherwise, you'd have to wait about 1h till warmup because of thermal drift. Hopefully I did not get this wrong but the heatsinks used for the SS output stages are face to face with close spacing to make this thermal drift uniform across channels (or differential signals?). I let the experts decipher and correct this ;-). Not sure if I'll have the patience to wait in line but I may be able to see it irl this w.e. arnaud
  9. arnaud

    Hifiman Edition 6 Headphones

    He is afaik, think the main bottleneck was efficiency but I suppose the delayed launch has a bit to do with him working on this.
  10. arnaud

    Sennheiser HD 800 Redux

    master troll of course
  11. arnaud

    Hifiman Edition 6 Headphones

    There was talk of something mk2 becoming something mk3 but I personally don't see the Omega 2 getting the treatment this time if it was already tweaked behind the scenes (pads) per people claiming current production Z3 are good. On the other hand, I recall Stax acknowledged the tiny SR003 could be more ergonomic so there's hope something is being done there. But indeed, nobody has a clue what will get released or when... arnaud
  12. arnaud

    Hifiman Edition 6 Headphones

    Stax amp coming this summer, sitting above the 007t2 but not quite T2 grade. My random guessing goes toward something similar to the kgst with sr009 price tag... Other than that, you pissed off the sole speaker of transdyn.... arnaud
  13. arnaud

    Hifiman Edition 6 Headphones

    Hifiman RE-2000$ ;-). There you go, the only mistake with the Edition-6 was the unfortunate naming, should have gone by HE-6000$. BTW, HE-9000$ is coming soon at CanJan event near you ! arnaud
  14. arnaud

    The Headcase Stax thread

    An attempt at translating the latest Stax tour / interview: http://www.head-fi.org/t/829843/stax-sr-009-and-t2-successors-confirmed-for-spring-2017/45#post_13130037 cheers, arnaud
  15. arnaud

    The Headcase Stax thread

    Correct, I think this was just the excitment to post big news while relying on google translate ;-). Now, what could 2018 big thing be if the amp is released next year?! A new ... ladder DAC? ;-) arnaud