If this info is already somewhere on the forum, i apologize - i searched and didn't see anything. I've been reading this forum for just a little while now, but I really don't post too often.
I just found and bought a (late 40's?) B-series JT-30 at an antique store. I figured it had the crystal element and wouldn't work anymore, but when I brought it home and plugged it in, it sounds outstanding!
I was wondering how to identify the element. It's definitely th original element, but there are absolutely no markings on the back of the element except for a small sticker that says: "Licensed under the patents of the Brush Development Company. See Patents. Notice inside and on carton." Then a few patent numbers.
Anywho...I was having trouble finding decent information online, so I figured there might be someone here with some idea.
If you've read this much, i already appreciate it!
Philippe. I appreciate the site. I had actually looked through that page already and couldn't find the element, though the '1940 Astatic Crystal" is pretty close. I've seen a few JT-30's around, but not too many painted all brown like this one...tho, still not much info on that element.
tbang, did you try a google search with Brush Development Company crystal microphone element? ---------- Violence is the last refuge of the incompetent. Isaac Asimov
Brush developed patents for how to make a crystal mic. There are some mics from the late 40's / early 50's with Brush crystals in them. Great elements but working ones are few and far between. Both early Shure and Astatic crystals had a sticker saying "manufactured under license from Brush Development Corp. ---------- /Greg
tbang, after my post I did a search and didn't find anything to help identify your element. The only interesting thing that I found is in Greg's post. Sorry I couldn't help.
Martin
---------- Violence is the last refuge of the incompetent. Isaac Asimov
Old Dog, jt30.com is a GREAT site and one of my favorites, but no luck (that i could find). Thanks for the suggestion - it's one of my favorites for info.
@ tbang More than likely it's a 99-131 from the 40's,.astitic didn't date their elements on th MC-151 & MC127,. Your element may even be a R7 crystal ( a replacement element )that someone changed out yrs ago ><
R7
Here is an original 1940 something Astitic ------------click Link Below -----------
The MC-101's are a totally different animal and the differene between that and an MC-151 is that the 151 has midrange presence rise and the 101 does NOT, and the same difference is with the ceramic version, which is MC-126 and MC-127, and the 126 doesn't have that presence rise either.
I forget the orginal crystal number, but the really old ones are NOT with the MC-101 or MC-126. ---------- Sincerely, Barbeque Bob Maglinte Boston, MA http://www.barbequebob.com CD available at http://www.cdbaby.com/cd/bbmaglinte
The MC-101's are a totally different animal and the differene between that and an MC-151 is that the 151 has midrange presence rise and the 101 does NOT, and the same difference is with the ceramic version, which is MC-126 and MC-127, and the 126 doesn't have that presence rise either.
I forget the orginal crystal number, but the really old ones are NOT with the MC-101 or MC-126. ---------- Sincerely, Barbeque Bob Maglinte Boston, MA http://www.barbequebob.com CD available at http://www.cdbaby.com/cd/bbmaglinte
my pleasure tbang. if i'm not mistaken, i've found this brush development corp. crystal in other brands of mics of this vintage. the gaskets are hard as rock and melded onto the element as a matter of course. the metal tends to tear at the pointed area dead center creating a volcano effect. i've NEVER found one in working order. ----------
MP doctor of semiotics and reed replacement.
"making the world a better place, one harmonica at a time"
The gasket is pretty hard, but with a little care, it came out very cleanly. I bought the mic at an antique store on a whim for about $65 not expecting it to work and thinking I would have to buy a new element (no big deal to do), but it is at least as loud as my Shure 707A that I recently plugged a 99A86 CM element into. Now I just have to make sure i don't drop it or anything stupid.
Very cool. I really appreciate the input. I wish I had some other samples of how this element sounds to compare mine to.
if it is as loud as your 99A, you won the lottery my friend. cool. my fav crystal is a brush. it's shaped like a pillbox and came out of an EV-920 Spherex. it's in an astatic biscuit. it's the only mic i use unless i feel like going acoustic through a PA vocal mic. ----------
MP doctor of semiotics and reed replacement.
"making the world a better place, one harmonica at a time"
brother tbang, actually, most anything sounds good through a 59 provided it was actually made in 1959 and restored to specs by a talented amp tech.
i'm amazed your bloody crystal works period, much less having some volume too. that crystal of yours is on the endangered species list. sadly, they are unable to have congress and reproduce:( ----------
MP doctor of semiotics and reed replacement.
"making the world a better place, one harmonica at a time"
This was a 59 bassman reissue done up by sonny jr...and you're right - everything through that sounds outstanding. Unfortunately, my current rig is a Blues Jr with a Weber Speaker and a couple smaller adjustments.... life keeps demanding I spend my money on less 'important' things like bills and food.
A nice new rig is on the horizon...just have to decide what'd be best...that'll be a tough decision.