Topic: Sony PCM-M10 - Battery box for DPA 4060

[Church-Audio]

Measuring the voltage at the BB after having connected the 4060, I found 2.79V and 2.53V on the 2 channels.
The BB resistors (metal 1%) measure 6.15 KOhm and 6.19 KOhm. 
I guess the voltage difference (coming the power from the same 9V battery) is due to the tolerances of the BB resistors and of the mics FET. The current absorbed by the 2 mics is anyway 1 mA to 1.05 mA, which should be ok.

Anyway, the voltage seen by the M-10 is less than 3V, similar to PIP given by the same M-10.
Being careful to connect the mics to the BB before connecting the BB to the M-10 (which is what I normally do in the connecting sequence of my "stealth" rig, the BB is in a pocket already connected to the mics, then I connect the BB to the M-10 in my jacket...) should be ok, I think.
I'll get low voltage, plastic film 10 micro Farad caps and test them anyway, to see their effect, but with no hurry...

Put caps in the circuit before you blow up your bias supply or worse on your Sony. There will be little to no effect if you use a 10uf cap. Also use metal film resistors not carbon. 1% Tolerance or .1% Also Use 4.7k or 10k for your DPA mics. Both values work fine. You must use caps for your battery box. You can use a larger value then 10uf if you want. I use tantalum caps they work fine for this application Poly also work well. Look at digikey.

Use surface mount parts if you want to keep it small. That's what I use on my battery boxes.

My battery box uses 10uf Tantalum + 10k or 4.7k resistors. Never had an issue with sound quality or noise.

[kleiner Rainer]

Chris,

NO tantalum caps EVER in audio circuits for coupling. Using them in this application means trouble, and I mean TROUBLE. I prefer low ESR high temperature electrolytics for audio, for example Panasonic FC, if I need 10uF or more. For lower values, I prefer WIMA MKS2 metallized Polyester film caps, since they are available up to 10uF in a compact package.

BTW I see no risk in gorlandos application. The voltage difference is low, and the currents can not reach dangerous values (there are also resistors in the Sony mic input for PIP (6k8 in most cases). He also states that he uses 1% metal film resistors.

Greetings,

Rainer

[Church-Audio]

Chris,

NO tantalum caps EVER in audio circuits for coupling. Using them in this application means trouble, and I mean TROUBLE. I prefer low ESR high temperature electrolytics for audio, for example Panasonic FC, if I need 10uF or more. For lower values, I prefer WIMA MKS2 metallized Polyester film caps, since they are available up to 10uF in a compact package.

BTW I see no risk in gorlandos application. The voltage difference is low, and the currents can not reach dangerous values (there are also resistors in the Sony mic input for PIP (6k8 in most cases). He also states that he uses 1% metal film resistors.

Greetings,

Rainer

strange some of the best mic preamps in the world use tantalum caps as audio coupling caps. you better tell them to stop. Including Neve, Midas,SSL and many signal processors.. Everyone had an opinion. I know what I see when I work on large consoles I see all kinds of caps it depends on the designer. and oh yeah I see them in Large format condenser mics made in Germany