"Ian Bell" wrote in message
...
It does make a note about
selecting the right position for the mic type switch which appears to
provide power for suitable electret types. If your mic has a built in
battery then I would recommend setting this switch to the dyn position to
avoid sending power to it.

Interesting. Since the 66B is, so far as I know, a condenser (it certainly
has an internal double AA battery driving it), I just assumed I should set
the R-1 to Condenser rather than Dynamic. But that sounds like an
interesting idea so I'll try it. Thanks.

Cheers,

Charles

"Charles H. Riggs, III" wrote in message
news
Interesting. Since the 66B is, so far as I know, a condenser (it
certainly
has an internal double AA battery driving it), I just assumed I should set
the R-1 to Condenser rather than Dynamic. But that sounds like an
interesting idea so I'll try it. Thanks.

I've tried it. I don't have test tones or anything like that to drive it,
but I believe I am getting a slightly higher level, so I'll try it in a for
real situation and see whether it gains me something. Thanks again for the
suggestion.

Cheers,

Charles

Charles H. Riggs, III wrote:

"Charles H. Riggs, III" wrote in message
news
Interesting. Since the 66B is, so far as I know, a condenser (it
certainly
has an internal double AA battery driving it), I just assumed I should
set
the R-1 to Condenser rather than Dynamic. But that sounds like an
interesting idea so I'll try it. Thanks.

I've tried it. I don't have test tones or anything like that to drive it,
but I believe I am getting a slightly higher level, so I'll try it in a
for
real situation and see whether it gains me something. Thanks again for
the suggestion.

Cheers,

Charles

My pleasure. One thing to note is that your mic probably has an AC coupled
output via an electroltytic capacitor. If the electret setting send a
voltage to the mike is may just possibly have done some damage to this.
Unlikely but possible nonetheless.

Ian
--
Ian Bell

*Repeating my rec.audio.tech post reply for this NewsGroup*

Plenty of probably Taiwanese step-up transformers, eg, in line 1/4" to 1/4"
or inline XLR barrel to 1/4" here for about $12.
Try Maplin for the latter
http://www.maplin.co.uk/Module.aspx?...TabID=1&source

"Jim Gregory" wrote in message
...
*Repeating my rec.audio.tech post reply for this NewsGroup*

Plenty of probably Taiwanese step-up transformers, eg, in line 1/4" to
1/4"
or inline XLR barrel to 1/4" here for about $12.
Try Maplin for the latter
http://www.maplin.co.uk/Module.aspx?...TabID=1&source



It has been interesting reading this thread and some of the replies
considering the header title "The Opposite Of A 10dB Pad".

A pad is an attenuator - a device that reduces the power level of a signal.
In this case in an impedance matched circuit a 10dB pad would result in a
x10 power loss. So the opposite of a loss is a gain - hey? So would not
10dB of amplification be the answer?

Many have suggested using a transformer. Transformers do not give you a
power gain. If anything, the average transformer may introduce a loss of
0.3dB or possibly more.

Transformers are impedance or voltage conversion devices not amplifiers or
gain devices as it appears to the common misconception in this thread.

If the input to the mixer / amplifier / recorder is high impedance (say
10kohms) and the microphone is a low impedance source (say 600 ohms) then a
step up transformer will solve the problem of low output voltage level.

The Sony ECM-66B has a balanced output impedance of 100 ohms @1kHz.
The Eridol R1 has an unbalanced microphone input impedance of 6.8kohms with
a sensitivity of -10dBu (~345mV) which is quite a high voltage level for a
microphone IMHO.

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.


Not perfect but and inexpensive DIY solution :

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.

Cheers,
Alan

"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

"Charles H. Riggs, III" wrote in message
...
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?

Never mind; I tried it and the hum was godawful. Scratch that idea!

Cheers,

Charles

"Charles H. Riggs, III" wrote in message
...
"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



Hi Charles,

The Shure A96F Line Matching Transformer
( http://www.shure.com/pdf/userguides/...ories/a96f.pdf ) should
work okay.

Setting the A96F to the 150 ohm option will give you the largest voltage
increase, however if it works okay on the standard setting of 600 ohms just
leave it at the factory default. You will not blow up your R1 recorder
using this device. The voltage levels on the specifications only refer to
the maximum voltages the transformer can handle before the core and windings
become saturated and distortion occurs. They do not indicate the actual
voltages on the windings.

Depending on the wiring of the microphone input socket on the R1, you may
need to cut the wire in the tip / ring / sleeve jack plug as shown in the
diagram on page 2 of the pdf guide in the link above.

Cheers,
Alan

"Alan Rutlidge iinet.net.au" rutlidge@NO_SPAM wrote in message
...
The Shure A96F Line Matching Transformer
( http://www.shure.com/pdf/userguides/...ories/a96f.pdf ) should
work okay.
Setting the A96F to the 150 ohm option will give you the largest voltage
increase

I took a look at the pdf document you mentioned
and right there, in black and white, it says "The A96F can be modified for
microphones rated at 150
 This
modification is only necessary if the output level from the A96F is
insufficient for your recording device." Well, of course, that is PRECISELY
my problem, and there's no doubt that making the modification and treating
the 66B as if it was a 150 ohm mike would appear to precisely solve my
problem.

I even opened up the transformer, precisely as described in the pdf
document. I even successfully identified all the crucial elements, the red
lead, the yellow lead, the location of pin 2, all of it. It was crystal
clear exactly what I had to do, namely cut the red lead, remove the
insulation from the end of the yellow lead and put it on the red lead, and
then solder the yellow lead onto pin 2 in place of the red lead. It would
probably take all of 10 minutes and my problem would be solved.

I opened the whole thing in hopes that I might be able to get
away with making the change while not needing to --

-- solder. You see, I have no soldering iron in the house, no solder, and
I've never touched one in my life, and I would feel like a child attempting
brain surgery. But wrapping lead around a contact is something I could have
gotten into, no problem.

Unfortunately, after close examination, it's obvious there is no way to
connect the lead to the pin except with solder. So there it sits, giving me
inadequate level, and
I'm stuck without the one tool and skill set which would solve this whole
problem.

Looks like this is a job for a soldering friend. Now the challenge is to
find a soldering friend. Which means one more hurdle, namely sweet-talking
a master solderer. I better
start talking!

Alternately, anyone know of a transformer for a mic with an XLR connector to
a stereo miniplug mike input which comes out of the box spitting out at 150
ohms rather than 600 ohms? Inquiring minds want to know.

Cheers,

Charles

"Alan Rutlidge iinet.net.au" rutlidge@NO_SPAM wrote in message
...
The Shure A96F Line Matching Transformer
( http://www.shure.com/pdf/userguides/...ories/a96f.pdf ) should
work okay.
Setting the A96F to the 150 ohm option will give you the largest voltage
increase...Depending on the wiring of the microphone input socket on the
R1, you may
need to cut the wire in the tip / ring / sleeve jack plug as shown in the
diagram on page 2 of the pdf guide in the link above.

I found a buddy handy with a soldering iron, and we made the change, as per
http://www.shure.com/pdf/userguides/...ories/a96f.pdf over to an
output for 150 ohms (or is it OF 150 ohms; not sure of the correct
terminology).

AND IT WORKED!!!!!!! My mike level is perfectly fine now going into the
Edirol R-1, and just why the #$%^&* Shure Transformer comes out of the box
set to some exotic mid-impedance level like 600 rather than a normal low
impedance level of 150, and just why the #$%^&* so-and-sos at Shure didn't
add an external switch to effect the impedance change rather than burying it
as a solder job I'll NEVER know.

But thank you, thank you, thank you. I was watching $1200 go down the drain
in recent days and not feeling too happy about it. Really appreciated.

Cheers,

Charles