[ericj]

Quote:

Originally Posted by Carl /img/forum/go_quote.gif Next up, do the SR50.

hahaha, sure.

Quote:

Originally Posted by wualta Yeah. [kicks empty tin can down the street] [tumbleweed joins urban litter blowing slowly across the scene] [promised shining future never arrives]

Aw man, you know, given the impossibility of repairing a stax electret driver (due to the impossibility of disassembling one without destroying it), and the availability of units with one bad driver, I'd have to be driven entirely by scientific interest.

And my o-scope has been in the closet since i moved, I won't have much of a work area until i finish remodeling upstairs.

Tell me about an electret that i can disassemble and reassemble, maybe I'll be interested in repairing them.

 

[Carl]

Quote:

Originally Posted by ericj /img/forum/go_quote.gif Tell me about an electret that i can disassemble and reassemble, maybe I'll be interested in repairing them.

In the Toshiba ones the electret material is in the electrodes rather than the diaphragm, so you could repair the diaphragm on one if you were feeling really hardcore.

 

[ericj]

Quote:

Originally Posted by Carl /img/forum/go_quote.gif In the Toshiba ones the electret material is in the electrodes rather than the diaphragm, so you could repair the diaphragm on one if you were feeling really hardcore.

Yeah . . . . I just have to get my hands on a Toshiba back-electret 'phone.

I came within spitting distance of winning an auction recently. We'll see if another pops up.

 

[wualta]

Quote:

Originally Posted by philodox Why not? Goo Gone works great... never had a problem with it dissolving anything and I am pretty convinced that is mostly urban myth in any case.

D-limonene, or possibly the solvents used to make it soluble/miscible in water will attack some plastics-- styrene in particular-- but mostly the stuff is harmless. Goo Gone just doesn't seem to have as much of it as De Solv It. Don't take my word for it, get both and compare 'em.

I once scared the guys over at AudioKarma by saying I used the water-based version of De Solv It on really cruddy old LPs. Spray 'em, scrub 'em, dry 'em, play 'em. Not enough ritual for some. But it works.

Quote:

Originally Posted by ericj Aw man, you know, given the impossibility of repairing a stax electret driver (due to the impossibility of disassembling one without destroying it), and the availability of units with one bad driver, I'd have to be driven entirely by scientific interest.

I know. I was just picking up on and amplifying out of all proportion the oceanic ennui and anomie lurking in your "Yeah, I guess I could. Some day." I LOL'd and LMAO'd because I've been there, especially on those days long ago right after I'd managed to blow one channel of a pair of electrostats and couldn't figure out why or how. I always suspected the MOVs I saw on the inputs but never got around to testing 'em.

 

[ericj]

A very late addendum - I was listening to my SR-80 Pro today and was annoyed that the white heatshrink is so visible through the back of the frame, so i disassembled them to install some black heatshrink (which i didn't have on hand when i initially rebuilt these).

Upon reassembly i discovered that I'd installed one of the frame-cups up-side-down.

I corrected that, and then had second thoughts. I'd built these with the wider edge of the frame-cup to the back initially. I went looking for pictures and discovered that from the factory the wide edge is toward the front.

And it turns out that this improves the bass substantally. Who woulda thunk it?

 

[Faust2D]

It's the little things...

 

[wualta]

[rubs eyes, does double take, stares, grabs monitor with both hands and stares again] Eh? Increases bass? Wha- ?

 

[spritzer]

Quote:

Originally Posted by wualta /img/forum/go_quote.gif [rubs eyes, does double take, stares, grabs monitor with both hands and stares again] Eh? Increases bass? Wha- ?

I know it's hard to believe...

The SR-80 can do bass but since mine don't have a headband they are on permanent test duty

 

[ericj]

Quote:

Originally Posted by wualta /img/forum/go_quote.gif [rubs eyes, does double take, stares, grabs monitor with both hands and stares again] Eh? Increases bass? Wha- ?

I would say that it's less recessed, yes. I do think the SR-30 has more bass, though.

 

[ourfpshero]

reviving old thread here..

just got a very nice condition sr84 setup. they are missing any foam or damping pads tho. just the drivers mounted inside the frames. the light foam is probably for dust purposes so my question here is
how does the damping pad affect the sound? and what can i use for one? i have plenty of felt from ortho madness

 

[charliex]

Fantastic work - congrats on bringing some classics back to life!

 

[wualta]

Quote:

Originally Posted by ourfpshero /img/forum/go_quote.gif just got a very nice condition sr84 setup. they are missing any foam or damping pads tho. just the drivers mounted inside the frames. the light foam is probably for dust purposes so my question here is how does the damping pad affect the sound? and what can i use for one? i have plenty of felt from ortho madness

I don't think felt is what you want here. The resonance of the much lighter diaphragm is well into the midrange, even the upper midrange, so a shock absorber technique won't work. My gut feeling has always been that the little rockwool discs (which, you'll notice, more or less float a short distance off the driver) are simply acoustic treatment, absorbers of midrange and treble. Try getting some small fiberglass pads from the hardware store and cutting them to fit the back cups of your SR 80 in the manner of the old Lambda Normal and Lambda Pro. With no treatment, the old Stax 'trets are defanitly midrange-centric and will wear you down.

 

[sohho]

great work!

 

[Moonwalker]

Hi!
 
Thanks for great article!
 
I just finished modding SR-80 earspeakers.
When I heard them side by side with new STAX 207 and 507, they were technically inferior IMO, but I still enjoy them very much.
They are just little old gems, improved when I changed the supraaural pads to circumaural, taken from Aurvana Live! headphones.
 
As for the damping, there's need for it, without any wool the sound becomes peaky and mid-centric, truly vintage.
 
Moonwalker
 

 

[rgonzale]

Nice informative DIY article. In case you're interested I went through a similar exercise adapting Monsoon planar-magnetic tweeters to build a pair of full-range headphones. I encountered similar problems with construction, damping etc... https://sites.google.com/site/ralphgonz/music-monstein-headphones