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Old March 21st 05, 03:30 AM posted to uk.rec.audio
Charles H. Riggs, III
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Posts: 14
Default The Opposite Of A 10dB Pad - 1:3 tranny

"Alan Rutlidge iinet.net.au" rutlidge@NO_SPAM wrote in message
...
An impedance matching transformer with a 1:68 impedance transformation

ratio
would be ideal and provide more than enough voltage increase to overcome

the
problem. Now all that is required is to source a suitable unit.


Currently I am using the Shure A96F Line Matching Transformer as a switching
station from the male XLR of the mike to the female stereo miniplug for the
R-1's mic input.

I am not experienced in reading specs for these devices, but here's some of
the information provided with it. Understand that I have attempted to
recreate the formatting WITHOUT invoking HTML formatting in my email client,
since I am not sure whether this newsgroup accepts HTML formatting.
Consequently there is a chance that the below may come out as so much
indecipherable gibberish. Here goes:

Impedance: Low impedance 600 ohms (supplied) or 150 ohms
Medium impedance: 2500 ohms
DC Resistance:
Low Impedance: 600 ohms winding: 56 ohms
150 ohms winding: 28 ohms
Voltage Ratio: 600 ohms
150 ohms
Low Impedance to medium impedance: +6 db +12 db
Maximum Recommended Input Levels
Source Winding Maximum
Impedance Being Driven Level
150 ohms 150 ohms .5 V
600 ohms 600 ohms 1.0 V
2500 ohms 2500 ohms 2.0 V


If you are handy with a soldering iron (or know someone who is) and want
make a unit for yourself a 600 ohms to 10 kohms tapped microphone
transformer can be found here -
http://www.altronics.com.au/index.as...=item&id=M0705 Specs exceed the
microphone's capability.
Connect your microphone across the red and green wires (600 ohm side) and
the yellow and blue wires (10 kohm side) to the microphone input on the

R1.
This should give you a healthy voltage increase. If you need more output
voltage try connecting the microphone across the red and black wires (300
ohm winding).
XLR sockets and 1/8" line jacks can be obtained form the same source as

well
as suitable shielded cable and a neat little box to put it all in.


The above might work very well for me. Unfortunately I am all thumbs at
that stuff, and would probably end up in the emergency room.

However you have given me a sort of crazy idea. What would happen if I take
the low to high impedance converter I got and deliberately plugged it into
the LOW impedance input (the mike input). Would I just blow out the mic
input and be without the R-1 for a few months while they repaired it, would
it probably simply result in a lot of clipping and distortion, or is there a
chance that might be a solution?

Cheers,

Charles