dpa 4099 guts

I fixed this for a friend. Just in case someone is interrested in it's XLR amp board.

IC should be: ADA4841

The bass response of the mic is quite poor imho. Which is undersandable because of the capsule size, however i expected better performance based on published graphs. Bass does extend low though, so it can be boosted with an EQ.

High end is quite impressive, the curve matches vintage u87 response without HF deemphasis. It is brighter than published graph, but still not as bright as most k67 replicas.

Noise performance is nothing to write home about.

Can't tell if there are some electronics around the capsule.

Pic 2

Pic 3

Out

The capsule

Capsule in the anti interference tube

This might be one of those posts where I talk to myself, but you never know if someone could benefit from it

I don't know if anyone investigated this, but I guess these MEMS mics could be used to make DIY versions of this mic.
I am BTW very surprised how well my Samsung Galaxy s8 records audio. The part number it uses is 3003-001244.

And here's some info on MEMS mics.
http://www.eeherald.com/section/design-guide/mems-microphone.html

Interesting! Thanks for posting.

This is a awesome doc i stumbled upon. I cant wait to start experimenting with LDCs.

https://www.edn.com/Pdf/ViewPdf?contentItemId=4429422

kingkorg said:

I fixed this for a friend.

Click to expand...

I'd love to hear a bit more on the symptoms and fix for the one you worked on. I've got one that is intermittent and I can't pin down if its the connection at the capsule or the XLR. A jiggle here and a jiggle there gets it back usually but unfortunately I haven't been able to isolate which end the flakey connection is on.

SubSpec said:

I'd love to hear a bit more on the symptoms and fix for the one you worked on. I've got one that is intermittent and I can't pin down if its the connection at the capsule or the XLR. A jiggle here and a jiggle there gets it back usually but unfortunately I haven't been able to isolate which end the flakey connection is on.

Click to expand...

IIRC it was just a bad contact in a conector.

That makes sense, I'm sure it's the same here. Will dig in some more, thanks for the reply!

Im curious about how a capsule's high impedance signal could travel all the way down that thin little cable and not pick up interference. My only assumption is there is some sort of active element at the transducer?

The MEMS mic elements are indeed enticing. I would like to examine making some little designs a-la 4099. I want to have a little percussion / sound healing table on my live performance with a low profile mic that can be setup with out being a big presence of space or catching the eye...

a bit sleep deprived so pardon the strange sentence syntax today.