Jump to content

Arthrimus

Returning Member
  • Posts

    112
  • Joined

  • Last visited

Everything posted by Arthrimus

  1. In that case maybe I could take one of the other amps off your hands for a while. You know, for the sake of the universe.
  2. Same, but looking at the board I don't see anything that would be too hard to do by hand, it would just require patience. I've soldered tsop32 flash packages by hand before and it doesn't look like there's anything on this board smaller than that.
  3. But I already feel like I'm careening at light speed down an equally slippery slope over on this side of the hill. I don't think my wallet could handle both! Maybe I'll just pick up an hd600 and end it there... Yeah, that won't be too bad. But then there's the hd800, and all of those orthos... Shit.
  4. I would love to build one of these, but I don't own any dynamic cans...
  5. Ling tosite sigure - i'mperfect If your down for some frantic post hardcore J-rock loaded with rapid tempo changes, incredibly complex (and inventive) guitar melodies and very shall we say "passionate" vocals, they're worth a listen. This album represents them at pretty much the top of their game to date so It's a good place to start if you've never heard them.
  6. That Carbon looks sexy as hell!
  7. This is a pro bias to normal bias adapter I cobbled together. It's a self bias circuit that taps R+ and gets chassis ground through an RCA plug to the amp. Just to prove the point of how easily one can build a stax compatible jack I rigged this one together with some female XLR pins, hot glue and a piece of delrin. Take that Mr.Speakers!
  8. Oh, I was more thinking about it in terms of reliability rather than sound quality. But that's probably a moot point too since these things apparently explode under what most would consider to be normal operating conditions.
  9. This is certainly true to a large degree. They've gotten very good at producing consumer electronics, but the fact that their military and aerospace industries are still so heavily reliant on Russia to produce reliable machines suggests that they still have a ways to go. Not knocking them one bit, they can produce some high quality stuff, but generally the best stuff coming out of China is coming out of factories that are owned by or are contracted and closely monitored by foreign companies who do the engineering and often provide the tooling used for production. I somehow doubt that Cavalli has the resources to aggressively manage the production of his designs, corners are almost certainly cut.
  10. Don't forget to cryo the source too. Everyone knows that 1s and 0s only sound their best after they've been exposed to -190c temperatures.
  11. Lithium Polymer batteries are Lithium Ion batteries BTW. Same basic chemistry just a different cell structure. All safety concerns that apply to one apply to the other.
  12. No, any commercial product with lithium cells has a protection circuit built in. If the cells dip below a certain voltage the protection circuit refuses to charge the cell. Due to the chemistry of lithium cells it can be dangerous to charge them if they pass below a certain voltage threshold, but you would have to bypass the protection circuit in the battery pack, which I assume isn't an issue in your case. A dead cell has little power stored in it so there is essentially no risk of explosion or fire, that usually happens due to overcharging or a charged cell suffering a puncture, or internal breakdown of some sort like what was happening to a lot of laptops in the late 2000s. The fire/explosion risk of lithium cells is directly related to their energy density, so a dead cell presents no real risk, although I wouldn't recommend trying to smash one.
  13. Lithium batteries definitely don't last well at low charge levels. 2/3 sounds about right, lithium cells take charge easy up to that point, but that last third is the toughest part on the battery. That's why all these quick charge cell phone technologies only work to around 60 to 70% then charge slowly up to 100%. Lithium cells naturally deplete charge over time and if a lithium cell goes completely flat it can never be recovered so you definitely don't want to store a lithium battery dead if you plan to ever use it again.
  14. I spent ten years in Indianapolis getting all "cultured" before returning home to the natural state
  15. I had thought they were priced at $1699 but I assumed that I had misremembered it when I saw them at $1899. Still seems like a killer deal assuming there is anyone over there that isn't in full scale panic mode over the possible economic fallout of Brexit.
  16. Anyone have any thoughts on the Lambda Nova Signature? I think I recall reading that these are one of the best Lambdas but I don't remember where. I've got my eye on a pair that looks to be in a little rough condition, but I'm thinking of shooting a low offer to the seller and making a project out of them. That is of course only if they have merit in comparison to my current Lambda Normal Bias dominated setup. Also anybody see that SR-007 and SRM-717 combo that's on ebay for $1899? Looks kinda suspect since the seller won't accept paypal, but if anybody is in the UK and can check them out in person before buying it looks like a hell of a deal. http://www.ebay.com/itm/STAX-SR007-Omega-earspeakers-Stax-SRM-717-Energiser-FREE-SHIPPING-/322167258002?hash=item4b02aa3b92:g:NHYAAOSwMNxXZn7G
  17. Sous vide filet mignon 122°F rare, finished with a simultaneous pan and torch sear in butter. Sauteed asparagus an mashed potatoes for sides. It was good BTW.
  18. Well I don't know how many normal bias only SRM-727s exist, but I have one. I got the bias board built and installed today. I'm still waiting for one of the resistor values to arrive here, so for the moment I've ghetto rigged a couple of 100K resistors in series to get 200K on the first resistor, and I've switched the second resistor in the divider to 300K because I needed some for my SRX plus build and I figured I'd kill two birds with one stone. B+ runs a little hot on my amp at 365v so all together this setup yields a 225v Bias. I've got some 165K resistors enroute to replace the rigged 200k resistor on the input side so the final board should yield around 235V bias which I'm thinking will be just fine. The board is mounted to the side of the chassis on some nylon standoffs. Ground and B+ were tapped off of the test points on the board as indicated in the picture below. For ground you could actually just ground to the chassis using brass standoffs and connect ground on the bias board to one of the standoffs. I didn't have any brass standoffs so I just ran a wire for ground. She's powered up and my Lambda NBs are singing with the amp completely untethered so I'm happy. Mod success! If anybody else wants to build a bias supply like this the above schematic and values are correct as confirmed by spritzer. I'd also like to amend my previous comments on the sound of this amp. It's been a slow burner for me, but I've really warmed up to the sound. It's a little warmer than the SRM-1 MK2 which I think in short term A-B testing makes the 727 sound a little veiled. But actually all of the detail is there, it's just not as in your face as with the SRM-1 Mk2. I'm not great with all the audiophile lingo, so it's tough for me to describe exactly what this amp does, but I guess if I had to generalize I'd say it sounds more natural and effortless than the SRM-1 Mk2. It's strength is especially apparent with percussion instruments. I've listened to this amp for around 20 hours at this point, going through a significant chunk of my music collection that I'm really familiar with, and I prefer it's presentation over the SRM-1 Mk2 on everything I've heard so far. Well I think I'm done here, this is my new main amp, at least until I build the SRX Plus, but that will probably be a while.
  19. Does anybody have a source for the female gold plated tulip sockets used in the teflon Stax jacks? I've scoured the internet looking for them and I guess I just don't know what to call them because I'm not finding anything.
  20. But by that same token balanced input could just a easily be added later when/if he ever has a balanced source. If it's not ever needed then no harm done.
  21. I was chatting with arnaud via PM about this earlier and, in reference to the likelihood that MrSpeaker's new wave of electrostatic headphones gaining a significant foothold, I said this: "No chance they could. Stax has a huge and loyal user base who doesn't give a crap about/hasn't ever heard of Head-Fi or MrSpeakers who will continue to be loyal customers. Stax will continue to know what they are doing (for the most part ) and continue to make high quality and reasonably priced products." There's really no scenario where another player makes any meaningful inroads in the electrostatic headphone market. It's just too niche, and we're all crazy people.
  22. There is. The ground lugs on both amps are bonded together. Edit: The mods are complete and it sounds a lot better now. This new version of the board has hardly any glue on the resistors so I was able to remove them with little damage. The feedback resistors tested good so I just reused them. The bass struck me as the most problematic thing with the amp before the mod, but now it's under control and sounds really good to these ears. The gain fix was also substantial, before the mod the 727 had to be turned past 2:00 to match the SRM-1 Mk2 at noon, now the situation is almost exactly reversed. I still don't think it sounds substantially better than the SRM-1 Mk2 but as I said before this was a necessary upgrade for my future plans.
  23. I recently converted a couple of SRD-7 energizers to pro bias so I swapped the sockets out of those.
  24. My step down transformer arrived today and the SRM-727a is singing. I'm still waiting for a couple of the components for my normal bias supply to get here so for now I'm borrowing the bias supply from my SRM-1 Mk2. I also volume matched them with a 50hz sine wave and a voltmeter and am doing some A-B comparisons. So far what I've learned is that the SRM-1 Mk2 is a really good sounding amp. I'm really not that impressed by the 727. Of course I haven't yet performed the feedback and gain mods, and I only have a pair of SR-Lambda NB to test with but still. I think in stock form the SRM-1 Mk2 probably sounds better than the 727a. This is all part of my multi year plan to acquire an Omega 2 so it was a necessary upgrade regardless. Off to do some mods!
×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.