I got the last two

[thermionix]

AFAIK, they're aren't any more of these in stock anywhere in the US.  They can still be found overseas, though.

[Kipper4]

What's it for?
I can see it's a diode. But why is it significant?
Cheers
Rich

[thermionix]

The MA150s were the "original original" diodes in the TS808.  The ones with the white bands, if you look at gut shots of old ones, and also specified in the old Ibanez service manual.  Will be clippers in my case.  Some of the vintage units used Toshiba 1S1588 (I have 10 of those) and I think there were one or two other types, maybe Panasonic 1S1588.  Some people say they all sound the same, but some people say alot of things.  IME, clipping diodes are critical, much more so than opamps.

I am currently overhauling my TS clone, last few parts should be here Monday.  I had an original years ago, it had such a smooth sound.  I've never heard a clone or reissue that sounded the same.  I'm gonna give it my best shot.

[Mark Hammer]

Somebody familiar with this forum membership, who speaks fluent English and Japanese, could make a bit of spare change swinging through the Akihibara on weekends.  Things which are either unobtainable elsewhere, or at least unobtainable in quantities large enough to be a catalog item, can be found there.

When Osamu (Sam) Hoshuyama spent a year here as visiting scientist, he made a trip back home to Tokyo to visit his family, and popped into the Akihibara while he was there.  He brought me back a pretty rare BA6110 and some 1S1588 diodes as a gift.  Try finding those here.

[J0K3RX]

I only briefly compared these M1MA141 dual switching diodes to the Panasonic MA2B150 but, from what I saw they are pretty close...

I may be wrong so, be nice

http://www.onsemi.com/pub_link/Collateral/M1MA141WKT1-D.PDF

[thermionix]

He brought me back a pretty rare BA6110 and some 1S1588 diodes as a gift.  Try finding those here.

I got my 1S1588s from Australia.  The cost wasn't so bad, for unobtainium, 10 of them shipped totalled $7US.  These MA150s were much worse because the vendor's cheapest shipping option was $7.99, and that's a neighboring state!  Obviously I would have bought more than two, but that was all they had, and there would be no more.  I have seen the MA150s for sale in Australia also, but shipping to the US was pretty high.

[thermionix]

An update.  My remaining overhaul parts came in today (woohoo!).  Among them were two 2SC1815s to replace the MPSA18s that were in my pedal.  Really glad I checked the pinout first!  Got it all buttoned up and it sounds great!  Hard to describe, but there had been a certain "sourness" to the sound that is now gone.  The distortion is now really smooth, too.  Not too edgy, not too fuzzy.  It might have a tad more bottom end than my old 808 did, but that could just be fresher electrolytics.  I have the MA150s in now, but they're socketed so I can try other clippers.  Also have a 1979 RC4558P in, also socketed.  I stole several of those from an old Peavey Deuce a few years ago.

[amptramp]

Thermionics, you could do the community a favour if you were to publish V-I curves for the diodes.  I am sure something else matches somewhere, if the diode characteristics are as important as you say.

[thermionix]

Thermionics, you could do the community a favour if you were to publish V-I curves for the diodes.  I am sure something else matches somewhere, if the diode characteristics are as important as you say.

The only thing I have to measure diodes is the "voltage drop" indication on my Fluke, which doesn't tell much.  I have to use my ears...and fingertips.  I do believe that the MA150s have a bit higher forward voltage than most similar diodes in this application.  But here's a link to the Panasonic datasheet:

http://pdf1.alldatasheet.com/datasheet-pdf/view/13910/PANASONIC/MA150.html