DIY PZM Build Video

[@FRobot-rx4kz]

I wonder if you also experimented with building a diy PCC microphone? I'd like to build one, but I wonder what capsule to get...

[@SoundSleuth]

Those require special capsules that I cant get a hold of. Sadness...

[@FRobot-rx4kz]

@@SoundSleuth oh...that's unfortunate.I just read that they contain a hypercardoid microphone capsule 😥...for some reason I thought they are just a simple cardoid campsule...

[@KravchenkoAudioPerth]

Nice comparison. What I liked the most is that the PZM mics picked up more room ambiance than the nearfield condensers. Your narration was rather pleasant sounding as well. You have given me a little to think through. I need a few mics for recording. Love the Micbuilders forum. Been a lurker for about 10 years.

[@SoundSleuth]

Thank you! These are great and very inexpensive to make. I used one of these on the Kick Drum on this video. I had a TSB2555B with my Op Amp circuit as the main kick mic and then a PZM about 4 feet in front of the kick and blended them in post. kzbin.info/www/bejne/rHm6iHqulpV8aLc

[@johnvcougar]

PZM makes the best full-bodied kick mic I've ever used. Combined with a carved cardioid dynamic on the beater, the blend gives any kick sound you want, and it's really simple to keep the two in -phase.

[@Jeff_AA8HF]

Just a note on the origin story. Crown sold several professional versions of their PZM mics for years before they licensed it to Radio Shack. I was a recording engineer during this era and I remember thinking that the radio shack version (which I bought and still own) signaled the end of the PZM as a serious professional mic. I was wrong, but the fad was definitely over and only a few engineers who appreciated what the PZM could do still used them.

[@SoundSleuth]

@@Jeff_AA8HF thanks! I still run into them occasionally

[@Angelo-vb6dg]

I didn't know about PZM mics but wow, they may sound amazing in certain use cases

[@SoundSleuth]

Yes they do!

[@johnvcougar]

SICK bass sound!

[@dfxmonkeyhead]

Might be a dumb question... But I didn't see anything to explain this in the vid or the Instructible. Is the mic capsule polarized? If so, how do we determine polarity? Thanks...

[@SoundSleuth]

It is polarized. One lead has a metal trace to the case. Hope that helps

[@p07a]

This was pleasantly educational. Thanks!

[@masterofnone9636]

Great stuff in Sound Sleuth Lab channel. Regarding "DIY PZM Build Video"... The diagram referenced is actually for a mic laying PERPENDICULAR to the boundary on a foam pad 1/16" thick (just FYI). Regardless, a 1/16" gap = 0.0625" The Crown Boundary Mic Guide says the gap (on a parallel capsule) should be 0.052" for a 1dB drop at 20 kHz, which is close enough. If, instead of gluing cardboard for the gap, one uses Gorilla Heavy Duty Mounting Tape, the gap (tape thickness) is 43 mils = 0.043" resulting in even less dB drop at 20kHz. AND a LOT easier than glue lol. Thanks for the great channel!

[@SoundSleuth]

Thanks, If you refer to the associated Instructable, we have updated that with a 3D printable capsule holder that makes the gap thinner and more repeatable. And you are correct about the distance!

[@masterofnone9636]

@@SoundSleuth Appreciate the response. I did notice the Instructables capsule holder (PZM Arm 3in v1.1), but passed for two reasons; it takes most of the DIY out of the project (DIY = fun?), and they are pretty expensive. With std. shipping, two holders cost $35.69! I just bought enough mahogany wood strips and Plexiglass to build eight PZMs for less than that. But if you don't have the tools/skill set/time/ for full DIY, they are a handy solution. (I'd be tempted if they were $5 for a pair lol). I'd send you my build pics, but don't see the option. Keep up the great work!

[@mestresplinter2467]

Amazing as always. Thank you for the material.

[@SoundSleuth]

Thank you!

[@Flitzefeuersocke]

Awesome instruction, thx. Tried to build it and I get quite some noise in the signal. How can I reduce it? Has it something to do with insulation of the capsule or the components at the male XLR?

[@SoundSleuth]

@@Flitzefeuersocke check that the components are not touching in the XLR shell

[@noahcwb]

Just got my capsules, just need to get the rest to make the mics

[@williamtell1477]

This is cool, is there any reason not to use a smaller sheet of lexan than 12"x12"

[@SoundSleuth]

I actually cut the 12” X 12” into smaller pieces.

[@stillidle1]

The cut down size is for transport convenience. The mics actually perform best when attached to a larger surface. If I were constructing my own and had 12" square lexan sheets, I'd use the whole sheet. The function of the mic backing, when it is at approx 5 inch or 6 inch square isn't usually to be suspended in the air to capture sound recording, but to serve as the base for mounting to a larger surface. If someone were recording a stage performance for instance, the ideal positioning for this mic type would be on the stage floor, on a near column, or on large transparent sheets suspended in the air, facing the performance. The use of transparent sheets is not an audio consideration but a visual one, making the recording process least obtrusive to the audience.

[@gerrycoogan6544]

@@stillidle1 Is that why the plate on the PZM is a square rather than a circle?

[@johnvcougar]

So: a suspended PZM pickup pattern behaves like an omni?

[@bryanblack190]

PZMs generally have a hemispheric pattern. The plate tends to block the other hemisphere and keeps it from being fully omni. The PZM does use an omni capsule (Pressure type vs. Pressure Gradient type).

[@ellisgl]

I wonder what it would sound like with a larger capsule (like the Transound)...

[@SoundSleuth]

This is one of those designs that needs the capsule to be small. What woudl be really nice is of the MEMS mics were quieter.

[@ellisgl]

@@SoundSleuth one the quietest mems I found is the ISC-40730.

[@mavamQ]

Hi, Sleuth, I'm thinking about low noise mics and how to reduce noise, (minimal background). At 4:25, If you put a common mode choke on the 47.2V and 41.9V lines, would this allow the Differential signal through but not Noise? I think noise would be common mode?

[@SoundSleuth]

Lamont, the noise is common mode. And it is rejected by the mic preamp's differential amplifier.

[@bleepboxes]

Nice project. Will try this for sure

[@SoundSleuth]

You will Like it!

[@bleepboxes]

@@SoundSleuth i once had two realistic pzm mics but at the time didnt really know what to do with them. Sometimes i put one in the kickdrum for recording as an extra. The realistic ones have a battery and are very cheaply build electronically. Im recording next month and found plans for a stereo head dummy mic. I bought a set of wm61 for it. Now i will also have to buy a set for these. Have you ever tried this on an upright piano?

[@woodshome11]

Great video, thanks.

[@lambda7652]

Hey, cool KZbin channel! im working on an Jfet + Opamp preamp myself and would be interested to find the Forum your talking about.

[@SoundSleuth]

Here you go groups.io/g/MicBuilders

[@mikepruett1745]

does anyone make pzm"S ANY GOOD

[@SoundSleuth]

These are pretty good and quite inexpensive to build