Rat Shack PZM mod

  • Thread starter Thread starter timboZ
  • Start date Start date
timboZ said:
I just got a Rat Shack PZM mic (33-1090b) and I want to convert it to phantom power.

Any ideas on a mod for it.
I seems to be the easiest one I could find.
http://www.celestial.com.au/~rosswood/data/images/PZM Mod.PDF
Click to expand...


Looks OK to me. You could add a 10uF filter cap on the power supply, in parallel with the 3.3K resistor. Also it doesn't state the value of the resistor above the switch, I assume that is stock. It might be worth playing with the values to get the voltage supply you want. The capsule (as opposed to the battery terminals) should see 2-3V or so.
 
timboZ said:
I just got a Rat Shack PZM mic (33-1090b) and I want to convert it to phantom power.

Any ideas on a mod for it.
I seems to be the easiest one I could find.
http://www.celestial.com.au/~rosswood/data/images/PZM Mod.PDF
Click to expand...
I've tried that one, and it doesn't work! I mangled a perfectly good PZM in the process too.
You can buy a kit that gets rid of that battery pack and amp in favor of a phantom powered setup here:
http://www.uneeda-audio.com/#pzm

It drastically improved the performance of my PZM, now much more sensitive and quiet.
 
Is it the new one or the old one? The former is not the same as the latter which was actually made by Crown. The new one is a different design.

Old on left, new on right.
 

Attachments

  • pzms.webp
    pzms.webp
    6.8 KB · Views: 238
superbeatballer said:
I've tried that one, and it doesn't work! I mangled a perfectly good PZM in the process too.
Click to expand...

Really? That's odd, that circuit is not that much different than the one in my little mic, except that mine is transformerless. If you still have the mic, check the voltages at the 3.3K resistor, and also the + pin of the capsule, and let us know what you get. Also I saw the article mentioned that the capsule needed to be reversed, as well as the cap, so check those two items. Finally, measure the mystery resistor to see what that is.
 
timboZ said:
This is the one I got...........(for free) :D :D :D
Click to expand...
You can't beat that price! I've seen bidding wars erupt on eBay over those mics!
 
MadAudio said:
You can't beat that price! I've seen bidding wars erupt on eBay over those mics!
Click to expand...

I have bid on a bunch of them, but when they get over $70 it's time for me to stop.
 
MadAudio said:
You can't beat that price! I've seen bidding wars erupt on eBay over those mics!
Click to expand...

eBay has been a strange place lately. I just picked up a KSM141 for $215, from a seller that had a pair up for auction, closing one minute apart. The other sold for 179! :eek: :eek: Moral of the story: never sell two items that close on the same day!!!

Knowing this, I've been slowly selling off my Beta 57s, the nicest ones first. I had one with clip, bag, and a 58 ball screen go for $75. Kinda disappointing. The next week, one with bag and 58 ball, but no clip, $76.

Now I have one with only the bag, no clip, it's up to $91 with 5 hours to go :confused: :confused: :confused:

It's mshilarious' definition of summer madness!!! :cool:
 
Does RS still sell PZMs? Anyone know when they
stopped selling the Crowns?
 
Brackish said:
Does RS still sell PZMs? Anyone know when they
stopped selling the Crowns?
Click to expand...
I'm not even sure that the new design is really a PZM (see my pic above). But the old ones have been out of production for at least 10 years, probably longer.....
 
MadAudio said:
I'm not even sure that the new design is really a PZM (see my pic above). But the old ones have been out of production for at least 10 years, probably longer.....
Click to expand...


Have you heard how the new ones compare to the
old ones?

P.S. I think "PZM" is a trademark of Crown and
the other similar mic's have to all themselves
"boundaries".
 
Brackish said:
Have you heard how the new ones compare to the
old ones?

P.S. I think "PZM" is a trademark of Crown and
the other similar mic's have to all themselves
"boundaries".
Click to expand...
Well yeah, those are my mics in that pic! The new ones sound very similar, though the high end is not quite as detailed.
 
Hmmm. What do you think I could get for my pair of them? I haven't used them in years. I keep thinking about doing one of the mods to them, but I never seem to get around to it.
 
timboZ said:
I'll give you $50 for the pair.
Click to expand...
My goal wasn't to announce a sale, just wondered what they'd be worth on the market. I still don't know the answer, but I would expect it to be a bit more than $50. Maybe I should just continue to try to find time to mod them myself.

Thanks just the same.

I'd expect to be able to see what they're worth by searching closed eBay auctions, but when I tried it nothing turned up. I'm probably doing it wrong.

BTW, there's one of these mics on eBay right now with a starting bid of $19.95. It closes in six days. I guess I could watch this one and see where it goes.
 
Keep them and mod them.
They tend to go for around $70 each on ebay.
 
You must log in or register to reply here.
Back
Top