[Scottsmrnyc]

Thanks everyone for your support in the loss of my parents.  It is great to get back to my music and our music and into life again.  I have been busy purchasing some new equipment; but it is mostly for my external system.  I think I am at the point where there is not a lot of stuff left to purchase.  I am still looking for a pair of Stax Sigma Non Pros and a couple of six prong extention cords.  Enjoy Scottsmrnyc

 

[svyr]

srs-2050a (sr-202+ srm252) were so great, until something screwed up and now on loud passages I get crackling at about 1khz... (the vol knob is at about 2 pm. The crackling happens on any source I plug them into and with different line-in cables)

  I take it, it can be anything from a faulty wall wart to faulty driver unit or earspeakers? 
 
If you're in Melbourne and with a pro bias stax amp and or headphones, and could spare 20 mins of your time for me to drop by and test my set with your gear

 
 
p.s. I don't suppose there is a place in Australia to service Stax headphones/amps that are out of warranty ?
 
p.s.s. can anyone lend me a 12v0.5a wall wart with center negative polarity that's definitely to spec?

 

[spritzer]

Does the sound go away or change in any way when you move the volume control? 

 

[svyr]

spritzer,
 
connected to different sources via line out it's fine until I turn the vol knob past 2 o'clock, then the crackling appears, but the sound never cuts out. 
 
 
It sounds like the crackling gets more prominent the louder I turn it up (the louder, the wider the frequency band around 1khz that's distorted... when the vol knob is fully turned, it's from about 300hz to 3khz)

 

[chinsettawong]

Hi Svyr,
 
It sounds like your amp clips at that high output level.  Wow, you really listen to your music very loudly.
 
Wachara C.

 

[svyr]

>Wow, you really listen to your music very loudly.
 
Depends on the CDs - may be up to about 3 o'clock for some classical where it's not really that loud. Generally at about 2 o'clock, minus some volume in the music player software
For other music it's usually at around noon... (if I listen to it at 3 o'clock it's usually loud enough to be painful for metal or rock). 
 
 
>It sounds like your amp clips at that high output level.
 
if you mean driver unit, then it sounds like a perfectly reasonable conclusion (at the same time, why not a faulty sr-202 that fails more as it gets louder?), If it's the driver unit - if Stax never wanted people to be able to turn the knob past 2 o'clock otherwise it cracks, why put dials and let it turn? (my ti based amp used to do the same, but it's was allowed to, since it cost < $50). Does anyone else with a srs-2050a get the same behavior for that volume? (i.e. is this normal for a srm-252a?)
 
Wonder what my sales pitch would be when I want to upgrade and sell this one. 'Wonderful Stax Basic system... Works great if your music has narrow dynamic range/is volume leveled'? ... heh
 
 
 
heh, this still means I need to plug the headphones into another driver unit and test... Please see http://www.head-fi.org/forum/thread/223263/the-stax-thread-new/13680#post_6763730 if you're reading this and live in Melb.
 
Any idea if I can mod the srm-252 not to clip? (so far I got to... not being able to open the case after removing the screws...

)

 

[spritzer]

The SRM-252 isn't a very powerful amp but it shouldn't be clipping into that load.  What I'd do is measure the DC adapter to make sure it is giving the amp enough voltage and then I'd take the top off the amp and look for any obvious signs of trouble. 

 

[bralk]

 
Quote:

Well seeing as how you're in Iceland, that makes a lot of sense.
That does look like what I need, though. And I hate to ask this considering you're the seller, but what are some cheaper alternatives? :/
 
Edit: After searching a bit more, I found this: http://www.amazon.com/VideoSecu-Switching-Adapter-Supply-Electronics/dp/B001UBOJ8M/ref=sr_1_30?ie=UTF8&s=musical-instruments&qid=1278371801&sr=8-30
 
Will this do the trick? Specs look the same as the Stax one, and this seems to be the right polarity. Anyone care to double check for me?
 
Edit again: The only difference I can spot between the two is that, though the + and - are on the right sides, the little C in the center is flipped. I don't know what that means.

 
I would stay away from switching PSUs as they are a potential source of electronic noise. Go for a regulated PSU.
 
cheers
 
Tom
 

 

[spritzer]

His best bet would be a bench supply if you want to go balls to the wall.  Fully regulated and polarity is just a matter of how you hook up the output wires.  It's what I'm currently using with my SRM-Xh...

 

[svyr]

>The SRM-252 isn't a very powerful amp but it shouldn't be clipping into that load.  What I'd do is measure the DC adapter to make sure it is giving the amp enough voltage and then I'd take the top off the amp and look for any obvious signs of trouble.
 
Did that yesterday - 12.3v without load. The adapter is rated as 1A and is from a local electronics store with lots of aus standard ticks (not that speaks about quality but still).
Not sure what it would give under load with music playing or what the real max current output is for it.
 
 
Hmmm, thank you, spritzer. I guess, I could buy a transformer for the original adapter (110 to 230v 230->110v) and test it with that. That's probably cheaper than getting a regulated psu, since those seem to be at least $70 here, vs $50 delivered for the voltage converter.

 

[Stein]

Alright bralk and spritzer, I take it this http://www.amazon.com/VideoSecu-Regulated-Supply-Adapter-PW12500R/dp/B000VRL632/ref=pd_sim_MI_1 would be the one to go for then?
 
EDIT: wait wait wait, I guess not? It says fully regulated, but also switching. I guess I should keep looking. If you guys have any suggestions, I'd happily take them.
 
I just might need a little bit of help figuring out how to actually access the wires so I can reverse the polarity, if that's okay with you, spritzer.

 

[jjinh]

Quote:

>The SRM-252 isn't a very powerful amp but it shouldn't be clipping into that load.  What I'd do is measure the DC adapter to make sure it is giving the amp enough voltage and then I'd take the top off the amp and look for any obvious signs of trouble.
 
Did that yesterday - 12.3v without load. The adapter is rated as 1A and is from a local electronics store with lots of aus standard ticks (not that speaks about quality but still).
Not sure what it would give under load with music playing or what the real max current output is for it.
 
 
Hmmm, thank you, spritzer. I guess, I could buy a transformer for the original adapter (110 to 230v 230->110v) and test it with that. That's probably cheaper than getting a regulated psu, since those seem to be at least $70 here, vs $50 delivered for the voltage converter.

Vlad, just noticed you mention your adapter is rated at 1A, but in this post above you mention the SRM-252 should take 0.5A; could that make a difference???
 
Also iirc you got your unit from Japan right (sorry my memory is crap). In that case I think it should probably be a 240v to 100v transformer.
 
Quote:

The SRM-252 isn't a very powerful amp but it shouldn't be clipping into that load.  What I'd do is measure the DC adapter to make sure it is giving the amp enough voltage and then I'd take the top off the amp and look for any obvious signs of trouble. 

I must be doing something wrong as I've tried to take of the cover of the SRM-252 in the past but after taking off the screws on the front I cannot get anything to budge. I was afraid to pull it a bit harder. Does one also have to take off the screws on the back??

 

[svyr]

>Vlad, just noticed you mention your adapter is rated at 1A, but in this post above you mention the SRM-252 should take 0.5A; could that make a difference???
 
1A is the max current the adapter I bought with the local plug should be able to output (if they were honest and it's not broken)
 
 
>Also iirc you got your unit from Japan right (sorry my memory is crap). In that case I think it should probably be a 240v to 100v transformer.
 
I did, but then I got the local plug 12v1a.
 
I have an option of getting a step down transformer and trying the org adapter as mentioned above.
 
>must be doing something wrong as I've tried to take of the cover of the SRM-252 in the past but after taking off the screws on the front I cannot get anything to budge. I was afraid to pull it a bit harder. Does one also have to take off the screws on the back??
 

I took the ones on the back off, and the one at the bottom, but it wouldn't budge. I don't have the hex drivers to unscrew the front ones, and I have no clue how to take off the volume knob.... Maybe we need to unscrew all of them. I never found a manual.

 

[dave650]

I became a Stax owner today.
Old SR5 headphones with an SRD-7 driver.
I bought them for well under 100 pounds shipped on ebay from a guy in France.
I am going to love these headphones! Why did I bother buying Grado SR325 ?
If old Stax headphones are this good, I cant wait to hear a new pair!

 

[jjinh]

Quote:

I became a Stax owner today.
Old SR5 headphones with an SRD-7 driver.
I bought them for well under 100 pounds shipped on ebay from a guy in France.
I am going to love these headphones! Why did I bother buying Grado SR325 ?
If old Stax headphones are this good, I cant wait to hear a new pair!

 
Congrats on the stax. My first stax (SR-202 + SRM-252) made my K701s sound so crap, not that I liked them in the first place.
 
And 'old' stax is apparently where all the good stuff is, e.g. SR-Λ sounds real sweet and isnt that bad on the wallet.