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bwck2000

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Everything posted by bwck2000

  1. I wonder will the position of the bolts allow me to use a pair of the original sr-omega earpads?
  2. After hearing your story I get to know which order it is. The custom border in China has been tight since COVID. They are taxing almost everything they receive so since then we are shipping headphone and product packaging separately exclusively for orders from China to avoid heavy tax. Furthermore, not only they will open each parcel that they receive they will also mess with it. According to your discription, In this case they put the headphone at the bottom of the cart box and took out most of the other shock absorption material. Not sure that they do this on purpose or not. From the photos you gave me the place where the paint falls off is always the same corner of the headband so that might explain it is due to impact during shipping. The discount you asked for a month ago for second unit shipping to USA is still valid and I am certain that the same problem will not happen again including the tilted plate thing because the shock absorption material will be intact throughout the journey. After replacement the warranty is still valid so please give us an email if you have further concerns. Since es1a is an omega clone and aims to recreate omega so it has to be omega-looking.
  3. I am sorry to hear that. We should be held responsible for any defect on our units upon arrival. Seems the primer under the paint is not adhering well onto the body. Please email me your situation and let me send you an replacement.
  4. There is also one winding only on my friend's 007ta. No any other copper wire sticking out. Seems bridging the cut winding for voltage change is not possible on those latest models anymore.
  5. Nice write up, from the amount of measurement graphs I can see how much effort you have put to it. Trimming down regions across the spectrum that you think is too much is a much more direct way to get a sound desired than trying out different gears. The 2K-3K region is particularly sensitive to our ears. To my experience, elevating it increase the glossiness of sound, adding more presence to each instrument and give people a good first impression on audition that it is a headphone with good sound quality. While lowering it make the headphone more relaxing, tolerable to long-term listening but the vocal might sounds void. I have had an earpad with inner face of the earpad cut open so that the foam is exposed to absorb this particular range. But the default one without the hole sounds closer to the original omega.
  6. You can use a multimeter to check the balance and offset of the amp that if they are on zero or anything near it. Another way to work on it is to loosen the 5 silver screw on the driver a bit using a hexagon screw driver.
  7. I have an es1a (omega clone ) loaner unit in US right now. I wonder anyone here would be interested to try them out ? Shoot me a pm if you do.
  8. I have an es1a loaner unit in US right now. I wonder anyone here would be interested to try them out ? Shoot me a pm if you do.
  9. I am using a1968 so its 450v config. Unlike the carbon, it has no adjustable ccs current so I didnt measure it. Maybe I need to order a pair of new heatsinks with longer fins. Its also a fail with no ventilation openings at the bottom but on the top only.
  10. I managed to get my kgsshv project done without creating some big mess and spark, and I want to thank KG for his design , Birgir and many member here for their generous contributions. oyaide L/i50 OFC is used as umbilical cords but is not shown here. later on a L/R balance control will be installed. The power and the amplifying section is about the same size so they can be stacked together. The heat sink size is less than ideal and it runs so hot that I can barely touch. My IR thermometer reads 47 oc but I think it is inaccurate due to the shiny appearance of the heatsink. But then I think at least these heat sinks are bigger than those on-board ones so this should not be a problem. Two stax plug are installed becoz I have dozens of them taken apart from stax extension cords. There are some small issues during startup. The power supply board had some sparking on the bias section becoz some paint is off and probably there are some small filament peeled off from the leg of the 1n4007. It needs some epoxy to cover up the arcing spot. There is also something with the amp board. At first there is no sound, balance sits at 700v and two burnt 50k resistor on each board next to the stn9360. It turns out that I installed some mpsa06 instead. Luckily it fires up after replacement. The first second it plays it blows 717 away. Big soundstage , great dynamic and details. Pretty much no complain and is hard to beat except that vocal can be more engaging. Drives omega, es1a and 007 equally well. I think it somehow sounds sweeter than the carbon I built long thime ago.
  11. You can check out here for reviews from users and loaner program participants, may give you some insight. There is also a video of es1a vs 009 AB comparison recording. Although the recording quality is not too good but it provide some references.
  12. I am glad to have received positive impressions on the es1a from chinsettawong and spritzer, Really appreciate that🤩 es1a is an alternative to totl electrostatics like the 007 mk1 and 009 for people who dislike their darkness/brightness, or owners of them who want to try something new. The es1a is brilliant in some aspects, and so do the 007 mk1 and 009. I particularly enjoy the wide soundstage, naturalness and airy, transparent highs of es1a. I hope that es1a will be refreshing to the community, since the 007 mk1 and 009 have been out for like a decade or two already. Es1a inherits some key elements from the original omega -- its neutralness , big soundstage ,and sense of spaciousness. But its true to say that they are two different creatures. I actually hear more people saying es1a sounds like an 009s than saying es1a sounds like an omega lmao. But the reason I kept the omega appearance is more from a cosmetic and marketing prespective, and perhaps it fills the little void in my heart that I used to not own an omega in my collection.So as the light headband clamping force it contributes to the non-fatigue listening experience of es1a and mimics what it is on omega but its not too friendly if you want to move around wearing it.
  13. I guess there is no need for a port mod anymore? The idea of the port mod is to do the role the little white piece does, blocking the ventilation path but the piece is preserved after a driver replacement in your 007.
  14. Two completely different creature, cant compare as if between two lambda models. The most obvious difference would be the soundstage. Its like a Jazz cafe VS a cathedral. The L700 sigma still holds lambda-level detail and transparency, unlike the original sigma. But the detail and the high frequency on the l700 sigma are just not as apparent as the L700.
  15. A milestone of my rare stax hunt: Quattro II🤪 So basically its a third-party CDP with a enlarged chassis, a very sophisticated power supply + DAC . They have separate power supplies for left and right channel as well as the digital section. The CD section has a plastic case but it is put in another aluminium case and on a wood base where the dac section is located. The CD pickup is Sanyo sf-88. Before the aged parts are replaced, The CDP sounded very neutral, fatigue-free with a special sense of spaciousness, but there was no real bass and dynamic. Then those big electrolytic caps are replaced with Nichicon KG , and Cardas rca and Furutech power socket are installed .After servicing the bass and dynamic is back. But it sounds a bit warm than before.
  16. While amateurs depend on luck and trials, you have craftsmanship 🤩 The most important thing needed to make great electrostatics......
  17. A dust free environment means a confined space with dust-free air sipply from HEPA Units filtering particles down to um-level and a positive air pressure to make sure that airflow is one-way-out only. It could be as small as a brench or as big as a factory. A normal working space along with a air purifier sitting at the corner or thorough cleaning is definately not a dust free enviroment, far from it. But in reality, there are some people who open their e stat driver, put it back and nothing happen. So whether dust gets into the driver or not is simply by chance. But if you do not want to throw the dice everytime , a dust free environment is definately needed. Some headphone makers revise e-stat designs from the typical stax type to make it less prone to dust contaminations so a dust free enviroment might not be necessary, but not for stax drivers.
  18. There is a possibility that the heating effect of the brass ring during the soldering process decrease the tensile strength of diaphragm and ultimately teared by aging, vibrations, its own tension etc.
  19. An omega arrived for imbalance repair. Pretty messed up inside with bias wire directly soldered on brass ring, faultly installed panel and worst of all a shadow seen at the part of the rim of the diaphragm , shown as a lunar shape at the bottom of the driver in the photo. Probably indicating a tear along the rim of the diaphragm. Treasure your omega(s) when they are still working ......
  20. Exactly, Can't do this without a dust free environment. For a simple upgrade on the original sigma 404 driver is good enough. The manipulation needed and the risk is manageable for a skillful DIYer.
  21. Reference: http://www.erji.net/forum.php?mod=viewthread&tid=2107767
  22. I posted a repair diary of Omega as a new post under Headphone section : I think its relevant so I will leave a link here.😄
  23. I posted a Chinese version of this article several months ago and now I translated it and put it here. I guess some people here will be interested. I hope you like it. Actually I have some more articles like this pending but I just don't have the time to write it up. --------------------------------------------------------------------------------------------------------------------------------- It all started about a year ago that a second hand sr-omega popped up in the local community. From time to time omegas show up on markets around the world but this one is different: an omega with 007 drivers installed. When the drivers are replaced, such omega drops its value to a fraction of its original. The seller listed it for 48888 RMB initially and sold it for like 20000 + at the end. When I first saw the listing, the first thing that caught my attention are neither the price nor the 007 drivers but one accessory laying aside, which is a pair of dead drivers I have never seen before. At first sight I know that it’s a prototype, a true unicorn that probably only one pair exists in the world. I am so curious on how it sounds and how it compares to 007 or 009 or the original omega. I messaged the seller right away and after some persuasion and explanation that I can give this driver a next life, I got it at a reasonable price. And it has become one of my biggest regret that I didn’t also purchase the omega itself that time, otherwise I can put it back into the place where the drivers belong to. Here is the driver itself. From this driver you can see several innovations made by Stax that has never been seen in other Stax models before it. The diaphragm is identical to a normal omega but the electrode is totally a different creature: copper plate similar to lambda sig etc. but much more refined. Over different regions of the electrode the thickness is different. The thicker copper comprises of the # pattern skeleton to give the rigidity while the thinner copper is perforated. You can see the same topology on 009 and 009s where they claim to have the MLER welding technology employed on the electrode. But this omega prototype electrode is in one piece and just as thick as a credit card. Furthermore, they rounded the edge of the perforation like what Stax does on 009S. Stax even make a sectional view illustration graph on their 009S promotion leaflet. Such treatment helps sound to radiate. To me it’s really impressive to see some characteristics of a flagship model today on a 30-year-old design. I wonder what the R&D department has been doing in these years But afterall it’s a prototype. It does have some problems: this electrode is too thin to give enough rigidity and prevent bending. They are curved to 5 o at most. Moreover, the area of attachment between the frame and the electrode is too small. It just peels due to aging. I see such defects in some modern designs too. Although its reasonable to have these issues because its 20+ years old, it does reveal that the one who designed it is not thoughtful enough. Perhaps that’s why it was never released to the market except the one on my desk. Besides the defects the design has, the driver itself is at a very bad condition. The drivers have been exposed to the external environment, so dust gets onto everywhere. The one who does not properly seal the package probably has never imagined that this driver will be repaired. It’s a pain in the ass to make the driver dust free again, especially when they are on the very fragile diaphragm. Normally I don’t accept requests to repair an exposed driver and I will give a new quote to clients who send me an exposed e-stat without telling me in advance . But I own this driver and I can bear the risk so that’s OK. The four electrodes are bent in different direction and magnitude as well as having detachment and failure of epoxy. Taking it apart and bent it manually is the only way out. It takes a lot of skill to bend a bent copper plate. Like you have to apply a certain amount of force on the copper and then you check how you have bent it by eye balling or a ruler, and you repeat this process a dozen times on one plate. You make it worse if you don’t know how. The most challenging part of it is that how much you bend an electrode actually affects the sound pressure on one side of the driver so at this point you just have to guess. I have neither the tool nor the file of the design, its all hiding in somewhere inside Stax’s archive library. At most of the time repairing a e-stat is more challenging and troublesome than making a new one. Aging will just make everything a mess and sometime you have to wipe the ass of someone who does not make the design good enough to withstand usage. Solvent removes dust and grease on the driver. It gets much trickier when it comes to cleaning the diaphragm. Effectiveness of a method to clean the diaphragm is an issue when there is just too much dust, not to mention the risk that you will break a diaphragm by puncture or sketch. At the end I decided to clean the diaphragm with solution. Although it will damage the coating, it means nothing to me as I can recoat it anyway to replace the old one which is probably damaged anyway. Cleaning done. They took away the dust screens so I have to prepare these as well. Last Step: assembly, the most important part of all steps. This several hours of work determines how long a driver can last before imbalance or noise occurs. Its my duty to make sure every edge and surface inside the driver is dust free. If not, dust will eventually get onto the diaphragm at some point in its service life and short the electrode and the diaphragm. Practically if the pollutant is much smaller than DS gap 0.5mm then its fine. All these procedures are done in a dust free environment. Soldering work Omega adopted a spring mechanism to connect the bias supply to the diaphragm. It is shaped like a tuning fork and it is odd (photo credits to audiohobby .pl ). I tried to make one but it just can’t grip firmly. After some days of having this troubling me I figured out a way, using HD600’s spring and I glad that it worked, at least for now. I used 007 cable, lambda sig headband, cnc machined and anodized aluminum casing and tailor made earpad. I am a proud Omega owner and I shipped the earpad for a clone. The result is satisfactory. I took away the back grill for inspection but I am kind of regret because I cannot put it back. The general sound signature of this omega prototype is somewhat identical to the original: natural, airy, transparent and clean. Its free of unnaturalness which can be found on 009 (please forgive me if you find this statement irritating, afterall the perception of sound is subjective). It has a larger soundstage than 009 for sure but I think 009 has more details than this one slightly. To me this prototype takes a midway approach between early-SN omega and Late-SN omega. It has a bit of the sweet coloration of an early omega while having much of the naturalness of a late omega. I found that early omega has a huge, diffused soundstage while a late omega has some in head effect which is unpleasant to me. Luckily this prototype is more on the early side. But still this prototype is different from the two regrading the proportion of width and depth of soundstage. I can’t explain more because I haven’t AB compare yet. What amaze me the most is how the prototype omega differs from the typical omega in the dynamic and bass region. The normal omega gives me an image of mellow, soft and relaxing in the bass region. Although 009 and 007 has better bass and impact I like the stress-free presentation of the original omega. The only thing omega put stress on me while I am wearing it is its price. In the prototype omega, I feel an enhancement on the impact, the speed and the amount of bass. Perhaps it’s the reason why they create this prototype, to improve on what the original is lacking. The density of imaging of sound also improves by a bit. Be caution that I cannot remove the effect of the different earpad and casing on the overall sound comparing to the original so the effect I mentioned above might be due to them. Despite all these merits, there is something lacking in this prototype: The openness of soundstage and the super-revealing details on the original omega. If omega scores 100 and 009 scores 85 in the aspect, I will give a 95 to this prototype. The transition from mesh electrode to plate electrode seems to be a double-sided sword. I remember in one of the Stax staff interviews they explained on Pros and Cons between mesh and plate electrodes. You give up something to exchange for another. Nothing is perfect unless you pay a double.
  24. Left to right: 404, L700 and 507 Sigma The one with 404 driver is more laid back and has more colouring while the 507 one has the best transparancy . But the L700 sigma is the best with a very full bodied mid bass and excellent 3D- imaging and soundstage I have never heard of in any other headphones. Love all three of them
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