Installing a large diaphragm capsule in an electret mic?

I saw some comments on YouTube from somebody saying they put a 34mm capsule in a BM-800 microphone (on of the cheap Chinese OEM electret ones, not the iSK ones) and properly polarized it by adding some capacitors and resistors to the stock PCB. Is there any recorded mods for this? Is something that's doable or something to be skeptical about? I don't see why anybody would make up modding a cheap mic, I just can't find any information about it through Google. If anyone knows what value resistors and capacitors to add or where you add them I'd like to know.

Yes, there are several options...

Do a google search for "Dorsey Schematic" and you will find one alternative using two resistors and two capacitors... or

Go to Micbuilders Yahoo Group, look for the Zapnspark user folder on the files area, and look for the DIYgenericNonElectret.pdf file, his approach uses just one resistor and one cap.

Or, search for "Pimped Alice" on EBay, and have a look at the schematic link. It uses same approach as Zapnspark.

Regards!

HL

homero.leal said:

Yes, there are several options...

Do a google search for "Dorsey Schematic" and you will find one alternative using two resistors and two capacitors... or

Go to Micbuilders Yahoo Group, look for the Zapnspark user folder on the files area, and look for the DIYgenericNonElectret.pdf file, his approach uses just one resistor and one cap.

Or, search for "Pimped Alice" on EBay, and have a look at the schematic link. It uses same approach as Zapnspark.

Regards!

HL

Click to expand...

Thanks I'll be sure to check those out.  On a somewhat related note if you apply something like caulking to the inside of the mic sleeve can you make these mics ring less when recording?

I fitted a 34mm capsule into a BM800  body and added a voltage multiplier to bias it, using stripboard and my own circuit (pretty standard though..... Schoeps circuit from here: http://www.sdiy.org/oid/mics/Schoeps.gif  and voltage multiplier ideas from here: http://www.gyraf.dk/schematics/Voltage_multipliers_with_CMOS_gates.pdf )

Pictures and circuit schematic here: http://www.jp137.com/lts/LDCX2.notes.pdf
The rubber sleeving on the frame edges helps to dampen the resonances in the sleeve - it's a pretty tight fit!

Not quite  in the same league as the ' top end' clone kits of course, but it's sure a LOT better than a standard BM800...... and using stripboard makes it easier ( and cheaper!) to experiment with different ideas and configurations...

You mean like this? https://groupdiy.com/index.php?topic=61845.msg783516#msg783516

Or like this?
http://khronscave.blogspot.com/2017/05/cheap-chinese-bm800-microphone-modding.html
http://khronscave.blogspot.com/2017/10/16-bm800-modding-part-2-ck12-k47.html

;D