i made a new battery box in use with a 12 volt mini battery. i needed no roll off so i used 2,2 uF capicators.
cool
how hard was that? did you have plans for it?
+T
Raphael
it's not hard only 4 parts.
--------------||---------------------------hot--- (left)
| 2.2 microfarad
from left mic | input capacitor
|
---hot--------+----10k ohm-- "+"
\
---ground----------------------)---+--------------------shield-----
/ |
---hot--------+----10k ohm-- "+" "-"
| resistor 9 volt
from right mic| battery
|
--------------||---------------------------hot--- (right)
2,2 microfarad
input capacitor
cool thanks
i think i am going to give this a shot some time
you should put this in the The Archive
Raphael
Very cool!
i'm going to stealth with it tomorrow.
let us know how it goes
Raphael
i didnt' tape we were lost couldn't find the venue and came in a half hour to late, i hope someone taped it was a verry good show. John Fogerty rocks. better luck next time.
Quote from: Weazel on March 26, 2005, 04:49:21 AM
i didnt' tape we were lost couldn't find the venue and came in a half hour to late, i hope someone taped it was a verry good show. John Fogerty rocks. better luck next time.
sorry to hear that
Raphael
Nice work.
If I were you, I'd isolate the soldered joins in order to avoid short circuit. (hope you understand my crappy tech english :o ).
A bit better schematics ;)
(http://roio.o106.com/bbox.gif)
have you run this yet?
Raphael
not yet. i tested it at home. but not in the field yet.
im sure it will work. now i await for a nice gig.
I built this + it successfully powered my DPA 4061's. The SP-Preamp does the job now though.
great to hear it workes there too. you used 12v battery's too or the 9 vollts?
Quote from: Weazel on April 12, 2005, 06:10:28 PM
great to hear it workes there too. you used 12v battery's too or the 9 vollts?
9V
Hey. I guess you are the man to ask. :)
I need a battery module with an adjustable bass roll-off filter (no level control needed).
A friend of mine will help me to build one but he doesn't really know how to do it (he is an electrician but doesn't know a thing about taping). Is it possible to get some info about this? I would appreciate it a lot as they are very expensive to buy.
It will be used together with my SHARP Minidisc recorder MD-MT770W and Sound Professionals Mini Binaural Microphones SP-BMC-2. Hopefully making some good recordings in the future.
i found this shematic on mic bulders. it has a switchable bass roll off.
you need to make it two times for stereo.
Oh! Thanks! :)
I guess this was a bit easier to understand. I'm just curious about one thing. In the description we can read "electret". Is that for electret mics only? I have mini binaureal mics. Could it make any difference? ::)
you'll be fine with your mics. this gives 9 volt plugin power to your mics. with this your mics are 'electred'.
oh yes the part with the battery and everything left from it you only have to builth once.
Why are there used those capacitors in series with battery??
from the info text file with this schematic.
There are 2 capacitors (C3, C4) across the 9 v battery. These are optional but
help bypass internal impedance of the battery at audio frequencies. The battery
powers the electret through a 5.6 k resistor (R1). I don't know if this value is
optimum - comments welcomed.
(http://roio.o106.com/bbox/soucastky.jpg)
Time to try out my soldering skills ;D
Quote from: kuba on April 19, 2005, 03:41:40 PM
[img /img]
Time to try out my soldering skills ;D
What kind of caps are those? Tantalum? Those aren't the best to put in the path of an audio signal.
Quote from: deadhoarse on April 19, 2005, 04:00:03 PM
What kind of caps are those? Tantalum? Those aren't the best to put in the path of an audio signal.
They're listed as ceramic...
Some comments since I see that you are using 12v instead of 9v...
I have experimented a little, and experimented with 9v vs 18v. I tested with two mics, AT853 and PC-62. 18v improved the AT853 performance, but the PC-62 suffered. I would try your setup both ways, that extra 3 volts may not be a good thing, then again it might.
Quote from: kuba on April 19, 2005, 04:27:36 PM
They're listed as ceramic...
Polypropylene metal film caps will better suit this project, I don't think ceramic are very good.
Quote from: deadhoarse on April 20, 2005, 12:25:32 AM
Polypropylene metal film caps will better suit this project, I don't think ceramic are very good.
Yeah, I know. However, there aren't any film caps with capacity lower than 1uF. I want to use 220nF...
Quote from: kuba on April 20, 2005, 03:55:52 AM
Yeah, I know. However, there aren't any film caps with capacity lower than 1uF. I want to use 220nF...
Um, there is a huge selection of film caps under 1uf. Go to digikey.com or mouser.com. This past week I ordered a bunch of metal poly capacitors for some new battery boxes.
Quote from: Karl on April 19, 2005, 05:21:25 PM
Some comments since I see that you are using 12v instead of 9v...
I have experimented a little, and experimented with 9v vs 18v. I tested with two mics, AT853 and PC-62. 18v improved the AT853 performance, but the PC-62 suffered. I would try your setup both ways, that extra 3 volts may not be a good thing, then again it might.
sound proffesionals use 12v now also, so i think it should be ok.
Quote from: deadhoarse on April 20, 2005, 09:18:28 AM
m, there is a huge selection of film caps under 1uf. Go to digikey.com or mouser.com. This past week I ordered a bunch of metal poly capacitors for some new battery boxes.
Hehe... I'm not in US, man :P