The Headcase Stax thread

[Dusty Chalk]

Dude!  Throw those out.  There aren't many non-toxic things worse than freezer burn on waffles.  Yes!  specifically on waffles.

[chinsettawong]

Gentlemen! Please help me fix my SRM252A.

 

 

 

One of the 4 250V, 22uF capacitors is leaky.  I've already replaced it.  The resistor, R40 (near the transformer), is burnt so bad that can't tell its value.  Does anybody have its schematic diagram? 

 

Wachara C.

[spritzer]

I just packed up my 252S... 

[chinsettawong]

Hi Birgir,

 

Do you think that R40 and R41 could be the same value?  I search pictures on Google and found a shot you made long ago.

 

[kevin gilmore]

never had a schematic of the power supply in that unit but i'm pretty sure its

the filter resistor and should be the same as r41

 

i think the srm212 is very similar, will look later

 

trace out the power suppy from the transformer, should be a couple

of diodes directly to a pair of caps, then resistors from those caps

to the second set of caps

Edited December 10, 2014 by kevin gilmore

[spritzer]

That's the SRM-Xh but they haven't changed the PSU much if at all.  Worth a try to use the same resistor. 

[chinsettawong]

The R40 and R41 are indeed identical.  I replace both with new resistors and now the amp is back to singing.

 

The root of the problem is that my PS has gone bad and put out 24VDC instead of 12VDC.  Somehow the excessive voltage only destroys one of the caps and R40. 

 

Thanks Kevin and Birgir for your help. 

 

Wachara C.

Edited December 10, 2014 by chinsettawong

[kevin gilmore]

switcher is completely open loop.  double the input voltage, and it will try

and make +/-500 or so. And parts will start flying.

[DefQon]

Man the K340's are shit sounding, both pair of mine how the fuck can anyone like these?

[Tachikoma]

I didn't think they were THAT bad when I had them, although I didn't think they were anything special either.

[morphsci]

Man the K340's are shit sounding, both pair of mine how the fuck can anyone like these?

They reverberate quite a bit if the density of material separating the cups approaches the density of air.

[DefQon]

Well both had white cotton dampening outside, took them out as it sounded worse with them. Right now I'm hearing decent low-end bass and laid back mids but afsdfkljsdflskdfj treble, some sibilance present as well and the that annoying highs you get from some Beyer's. I should hunt down another pair that is straight out in working condition. Can't be my amp as I tested it off a loaned Dynahi.

Edited December 11, 2014 by DefQon

[nopants]

The 009s are so polite compared to the 007s

[DefQon]

Well got some ESL speaker repair kit gonna make me some ESL headphones. Should be fun assuming I don't electrocute myself in the process of testing. 

[TMoney]

EDIT: Well, what do you know, turns out they sent it Monday but they didn't bother to tell me it had shipped. *sigh*.

 

Email I sent this morning to Yama's. Getting the 009s repaired/replaced has been a nightmare.

 

 

 

Hi Tats,

I have tried to be patient and reasonable, but it has now been more than a month and a half since you first received my pair of damaged SR-009s. I still have not received my trade-in replacement. I have not received any shipping info. I have not even received any date on when that replacement might arrive.

Due to the amount of time I have been made to wait, I think a 10% discount on our previously agreed upon price for the trade-in is reasonable. If I had known back in the beginning of November that I still would not have this issue resolved I would not have chosen to have my SR-009s replaced and I would have pursued another option for having my SR-009s repaired.

I think $2,700 ($3,000 - $300) is a reasonable price given the delays I’ve had to endure. If you can meet me at that price then I will continue to wait a reasonable amount of additional time for the replacement pair to become available.

If you do not agree to the additional 10% discount, I’d appreciate it if you sent back my original damaged pair of SR-009s back to me. I would expect that you would waive any diagnosis and labor fees.

Thank you

Edited December 18, 2014 by TMoney

[nopants]

before I got lazy and started taking stuff apart myself I worked with high end workshop in the uk, despite being in norcal

[Tompoodie]

Hello. FIrst  post ever. I have used AKG 240 for years, to avoid disturbing wife. I now know cans can easily exceed sound of speakers (except tactile bass) costing $20K and up. I want electrostat cans to give me an experience I can't have with my speakers... to feel like the musicians are in the room.  I won't ever spend more than $20K on speakers!  I have Harbeth Compact7's with REL sub. Source is up to snuff, though not crazy expensive: modified Metrum Octave with Empirical Audio Pace Car reclocker.

 

I believe Stax's exceptional design is likely what would suit me best.  I will be at CanJam this year, and will then probably make a Stax purchase.

 

Question:  I am trying to decide betwen 407, 507, 007 Mk 1 and 2, and 009.  A few users actually prefer the sound of the 507 to the O2's and the 009.

I am freaked out by the channel imbalance still happening after 3.5 years the 009's have been on the market. OTOH a majority say 009 is hands down the best, with appropriate amp, generally BHSE or KGSSHV.

ASR and Spritzer, whose opinions I respect, are an elite minority who strongly favor O2 Mk1 over the 009.

 

From forums I have concluded: 407 or 507 (depending which fit my head better as sound quality is very close) with the synergy and low cost of the 323 amp may be best value. Consensus seems to be that 507 sound is very close to 007 and 009 (more so than past Lambdas). A few actually prefer the new Lambda sound to the 009.

The 507 diaphragm can be fixed DIY.  The 507/323 combo is a low enough price that I would buy in US minimizing the PJ/channel imbalance risk.

I remain open to 007 MK1 or Mk2 if they are really that much better relative to cost.

I listen to rock/singer-songwriter/jazz/classical in equal measure.

 

I would greatly appreciate your collective wisdom and how to use my time at CanJam 3 months to guide me. 

 

Tompoodie, Los Angeles, CA

[spritzer]

Anybody preferring the 507 to anything Stax have ever made must be on crack.  They are that bad...  Only the 207 is useable of the new Lambdas but naturally Stax could have fixed the recent units like they did with the 009.  Haven't bothered to get any of them just to try it out. 

 

You really can't fix any of the drivers DIY.  As soon as you open them up they are compromised in terms of dust and debris. 

[Tompoodie]

Spritzer, I am honored that you were the first to respond to my first post ever!!

I will give your opinion considerable weight.  207s (smoother treble than 507?) with a 323 could be a relatively cheap interim solution until going for the end game; 009 vs 007 Mk1 vs Mk 2 seems like such a personal decision it has to be made by listening.

[DefQon]

I would take sprizters comment of the 507's being bad from the new Lambdas with much weight they are pretty bad and unbalanced sounding. If you can't get an O2 mk1 or 009 look into the vintage Lambda frame earspeakers as they all round better then the new stuff I.e Lambda/pro/signature, Nova signature, 202's etc.

[mypasswordis]

Been listening to my SR-5 and SR-5NB the past few days, forgot how good they sounded. I haven't heard any of the latest gen Lambdas but it's pretty hard to go wrong with vintage Stax.

[spurdo]

New owner of a SR-Lambda Signature (with new stax headband) and Stúfur built by Spritzer here. I love the details and its sound signature, and I haven't found anything I dislike so far. Its first owner had different tubes, but I'm using the original General Electric and JJs for now. http://i.imgur.com/xKU7xOV.jpg

[spritzer]

Nice to see that one again.    The JJ ECC83S are about as good as it gets so they would be my choice. 

 

It would be fun to build a few more of these with a CCS load for both stages (well sink for the front end).  Would be a killer budget Stax amp. 

[Ali-Pacha]

Got my hands on some SR-007 mk1. Now I DO understand all this power-craving needs. The thing is pretty flat and almost boring out of my Stax amps (SRM-727II and SRM-1/mk2), I have to go on SRD-7/mk2 to get some dynamics, an I loose lots of details / extension. I hold my ticket in the BHSE waiting line strong (since may).

How do you say it...? Yeah, MOAAR 

 

Ali

[DefQon]

I'm still kicking myself for missing out on a deal on our local ebay for a mint condition $1.2k Stax O2 MK1 just before Xmas. Forgot to place snipe bids as I was at work.