JaZZed up Stax Lambda Pro's

[moray james]

I was impressed to see the great work done on these two sets of Stax Lambda Pro drives by Jazz over at Head Fi that I thought that his post should be duplicated here for members to see. Don't know how many times I played with my Lambda phones on my head to see if I could simulate Sigma style sound. Kudos to Jazz for two jobs well done.

See JaZZ's custom made Stax Phones here...Homemade Headphones? - Head-Fi: Covering Headphones, Earphones and Portable Audio

Jazz's comments below.....

The idea of making my own housings for Stax drivers was born out of my experience with the Lambda and the Sigma Pro. Whereas the Lambda sounded too shrill (with the SRM-1 [?]) -- and almost literally caused toothache --, the Sigma's sound was too boomy, diffuse, muddy and lacked midrange (with the SRM-T1). I wanted to strike a balance between both, conveying some of the Sigma's spatiality and bass fullness, but preserving the electrostatic virtues such as resolution, accuracy, detail and refinement -- which were mostly lost with the Sigma -- and at the same time reduce the Lambda's treble glare.

So I decided to go the middle course between the two designs, i.e. angling the drivers, but clearly less than the Sigma's ~80

[Duggeh]

It would be my expectation that people here already know about them.

[spritzer]

There is very little Stax related that we don't know of... I do wonder though that the extra angle isn't doing more harm then good and the true magic if due to the very stiff chassis.

[mypasswordis]

Wow, not bad at all. Maybe I'll try something like that with my Lambda. I'd prefer a finer metal mesh for aesthetics but that also increases reflections.

[moray james]

Before I bought my Pro Lambda /SRM1 rig way back in the 80's I was torn between the Lambda and the Sigma. I listened to both but the length of time I had to do so was limited. I really wanted to have a phone that had the qualities of both. In the end I choose the Lambda's. I used to listen to them and play with the angle of the elements relative to my ears by compressing the the cushions to simulate the Sigma effect and often wished that there was something in between the two models. To me JaZZ has nailed it.

I think that Birgir is right in how important a solid frame structure is. The slanted O2 pads that I have on my Smeggy Gamma phones is a nice compromize in that they permit one to adjust the angle of incident between the element and the ear.

Regarding the protective grills I think that they look very good and different size openings could be played with. Another option might be to include a layer of 1/16 inch open insect screen beneath the metal grid. This can be obtained in black fiberglass which could be tensioned and fixed into place then covered by the metal grid. Perhaps Smeggy might be willing to share his source for the plastic grills he uses (at least I think the grills in my phones are plastic they might be powder coated aluminum) which look superb (the whole phone looks superb). I really enjoy seeing people do such excellent work and very much appreciate that they share their work with all of us.

[faust3d]

I would like to see a SR-303/404 or ESP950 driver put into a Sigma like stiff chassis made out of some hard wood or magnesium alloy. I know I said this several times, but I will bring this up again in hopes of someone doing this. I feel that Sigma's design is one of the best soundstage wise and with better vibration control and drivers this design can sound even more realistic than SR-007, and god knows I love my SR-007.

[Smeggy]

I did my own version which was less radical and reversible, worked pretty well too.

[faust3d]

Did you make the wadges yourself?

[Smeggy]

Yep, just a block of rock maple drilled through to match the driver size and sawed into a pair of wedges.

[spritzer]

I've been cooking up plans to make a HE90 like headphone (with the real earpads and a similar headband) with ESP950 drivers. They are works of art and Koss didn't fall into the trap, thinner membrane=moar better. The chassis would be beach ply but instead of gluing the drivers to the baffle which is then screwed into the housing, I would clamp the drivers in place. Still it looks like I just won a SR-202 for 3900Yen (pretty beat up though) so there I have some extra drivers.

[Duggeh]

Whats the diaphragm thickness on the 950? 1.5?

[spritzer]

Yup.

[faust3d]

Full specs from Koss brochure in case someone is interested:

ESP/950 Headphones:

Frequency Response: 8-35,000 Hz

Impedance: 100k ohms

Sensitivity: 104 dB SPL/1mW

Distortion <0.01%

Diaphragm radiating surface area: 46.6 sq. cm

Diaphragm: Ultra-low mass 1.5 micron C grade polyester film electron beam coated with proprietary semiconductive material 250

[Duggeh]

C grade? Isn't that 2 grades below what we snobs demand?

[cetoole]

I've been cooking up plans to make a HE90 like headphone (with the real earpads and a similar headband) with ESP950 drivers. They are works of art and Koss didn't fall into the trap, thinner membrane=moar better. The chassis would be beach ply but instead of gluing the drivers to the baffle which is then screwed into the housing, I would clamp the drivers in place.

Want.

[faust3d]

C grade? Isn't that 2 grades below what we snobs demand?

Maybe A grade is used in defense and NASA stuff only:p

[Duggeh]

Maybe A grade is used in defense and NASA stuff only:p

Fuck that exclusive discriminative shit dude. I need that stuff for my DIY aspirations. This gold plated soldering iron isn't just for show.

[faust3d]

Do you also need semiconductive material 250

[spritzer]

There are two grades of mylar, C and some other I can never remember. The C here stands for capacitor and is made under stricter QC then the other grade i.e. if it says 1.5um then it is 1.5um within some small range of error.

[moray james]

for those who are interested here is an interesting patent by Rudolf Gorike of AKG. you can find it by going to Google Patent and searching for this US patent number 4, 158,753. hope you find this usefull.

[derekbmn]

for those who are interested here is an interesting patent by Rudolf Gorike of AKG. you can find it by going to Google Patent and searching for this US patent number 4,158,753. hope you find this usefull.

Looks like an idea that never got off the ground in that form, but from description it sounds like a K340. Very interesting.