Superlux S502 MK2 test, teardown and improvements

[MicUlli]

where we can find rhis pcbs

See Post #67 in this thread

 

[jp8]

Outstanding: frequency response S502 (1st version).
Find attached some pics...

Hi MicUlli,

Could you also share frequency response charts of both the mk1 and mk2 versions? Preferably at 0, 90 and 180 degrees, if you can. I could do them myself with the mics I have, but I do not fully trust the results

Jan

 

[Emmathom]

Well I was already very satisfied with the sound of my S502 1rst version... now it's Xmas time !

I'm impatient to install my new board...

 

[janpanis]

Bingo. That’s what I get for trying just once and being too frustrated with tiny tools to even think about trying the other way.

Alas, the capsules are electret and soldered a way way (ring is conected to backplate and ground) that one can't test them in Schoepses, though they would fit. Electronics are very basic with a double opamp GS6002. They sound good and the "finish" is very nice Schoepsy.

 

[MicUlli]

Hi MicUlli,

Could you also share frequency response charts of both the mk1 and mk2 versions? Preferably at 0, 90 and 180 degrees, if you can. I could do them myself with the mics I have, but I do not fully trust the results

Jan

Hi Jan,
the frequency response of the S502MKII under different incident angles was already posted in #56. It has not changed significantly with my electronics.

Find attached the frequency response of the S502 with my electronics. I purchased the S502 from "Kleinanzeigen" as "defekt". And it was, so i didnt try to repair the old electronics...

Very pleasing are the noise measurement results:
S502MKII self noise is 14,1 dBA (SPL) left channel and 14,3 dBA (SPL) right channel. Sensivity is -37,4 dBV left channel and -37,7 dBV right channel.
Overload point is around 138 dB (SPL).
S502 (1st version) self noise 15,6 dBA (SPL) left and 16,2 dBA (SPL) right. Sensivity is -43,4 dBV left and -43,7 dBV right. Overload point is around 144 dB (SPL).

No noise artefacts above 20kHz thanks to the very stable JFET-oscillator (420kHz)

Now shipping of the "repair kits" will start...

Best regards MicUlli

 

[jp8]

Thanks a lot for sharing! I skimmed through your posts too fast and missed your post with the S502 MK2 charts. Sorry.

Jan

 

[ubxf]

Hi Jan,
the frequency response of the S502MKII under different incident angles was already posted in #56. It has not changed significantly with my electronics.

Find attached the frequency response of the S502 with my electronics. I purchased the S502 from "Kleinanzeigen" as "defekt". And it was, so i didnt try to repair the old electronics...

Very pleasing are the noise measurement results:
S502MKII self noise is 14,1 dBA (SPL) left channel and 14,3 dBA (SPL) right channel. Sensivity is -37,4 dBV left channel and -37,7 dBV right channel.
Overload point is around 138 dB (SPL).
S502 (1st version) self noise 15,6 dBA (SPL) left and 16,2 dBA (SPL) right. Sensivity is -43,4 dBV left and -43,7 dBV right. Overload point is around 144 dB (SPL).

No noise artefacts above 20kHz thanks to the very stable JFET-oscillator (420kHz)

Now shipping of the "repair kits" will start...

Best regards MicUlli

Great news thank you, I noticed that a fair amount of smd components are required. I've only done repair on a single smd component before. Is it reasonable to attempt building this or is it too big of a step for smd beginner ?

 

[MicUlli]

Great news thank you, I noticed that a fair amount of smd components are required. I've only done repair on a single smd component before. Is it reasonable to attempt building this or is it too big of a step for smd beginner ?

Well, it depends...
You need a small solder iron tip (0,4..0,6mm), a small pair of tweezers, thin solder wire and a good magnifier, preferable binocular.
Fix the pcb on a flat working plate (with tape). Presolder one of the pads of the component. Then position the component
and melt the presoldered pad. That is the best way to handle smd components. Then solder the remaining pads.
AND dont drink too much coffee
BR MicUlli