Diy budget PZM

[Rob Flinn]

Just recently I did the balanced and phantom powered conversion to a pair of tandy realistic pzm's for someone. Looking at the price these mics go for now I decided make a pair on a shoestring budget. This project I did over Christmas whilst I was at my house in France over Christmas. I bought a few (supposed) panasonic capsules from ebay for a few £'s, & some electret preamps from Aliexpress for something like $3 each. I had some aluminium plate lying around which I cut in half to make a pair. I bought some small cast aluminoium boxes to house the preamps & an xlr socket. I made the capsule holder out of a bit of ash that I got from a charity shop in France for a euro. All in all & think the overall cost for the pair was something like £20 u.k They seem to sound pretty decent for the money. I'm sure they could probably be optimised a bit further. I hate the way the realistic ones have that thin cable going to the battery box so I did away with that & mounted the elxtronics box on the edge of the plate. Maybe I shouldn't have mounted the box on the plate because of reflections etc. However, I probably won't spend the time doing it because they sound pretty good as is.

 

[k brown]

If you're willing to do a little surgery to the cantilever, the (slightly larger) Primo EM272 will sound better and be much quieter (EM273 even better, if you can deal with a three-wire capsule).

If you're making something from scratch, building them with the capsule body parallel to the plate (diaphragm at right-angle) is much simpler to build and more rugged. This is the way most commercial boundary mics are made (Shure, AT, even Schoeps).

 

[Rob Flinn]

If you're willing to do a little surgery to the cantilever, the (slightly larger) Primo EM272 will sound better and be much quieter (EM273 even better, if you can deal with a three-wire capsule).

I'm sure you're probably right. I think I would probably just build another pair if I wind up trying some better capsules. I was just trying to do this really cheap. The pair of mics cost me less than the primo capsule. Like I said they sound pretty decent as is. I'm not really sure the things I'm likely to use them for I really need them to be too optimal.

 

[Gus]

Thanks for posting this maybe it will get me to build some inspired by the Neumann triangle boundary microphones.
If you look up the papers on this there is nautilus shaped design that looks interesting
I think I might use MDF.

Still thinking about what capsule to use

 

[k brown]

Thanks for posting this maybe it will get me to build some inspired by the Neumann triangle pressure zone microphones.
If you look up the papers on this there is nautilus shaped design that looks interesting
I think I might use MDF.

Still thinking about what capsule to use

I did just that; based on the Neumann research papers. Used 1/4" hardboard. Even made two mirror-image spirals into a SASS-type stereo mic (unfortunately, looked like a head with giant ears!). Still use a couple of GFM-style triangles made of 1/4" plexi, with Primo EM273s in them.

I use these more often, though - I can put any nice SDC mic in it (best used with compact heads that don't have XLR connectors (Rode NT55, etc.), even card or hypercard. Shock mount reduces structure-borne vibrations. Made 'em with ABS sheet. Inspired by the Schoeps BLC.