The Opposite Of A 10db Pad
 

Dear fellow audiophiles,

I'm looking for the opposite of a 10db pad for my unidirectional ECM-66B
lavalier mike. Its output turns out to be quite a bit lower than is ideal
for the Edirol R-1 recorder's mic input, averaging about 10db lower than is
ideal for good SN/R, even with the R-1's input volume set to maximum!

Don't know whether such an animal exists, but I figured this would be a
good place to ask. If a really tiny very portable 10db gain doohinky thingy
doesn't even exist, I'd be open to other suggested solutions. Thanks much.

Cheers,

Charles

The Opposite Of A 10db Pad
 

In article ,
"Charles H. Riggs, III" wrote:
I'm looking for the opposite of a 10db pad for my unidirectional
ECM-66B lavalier mike. Its output turns out to be quite a bit lower
than is ideal for the Edirol R-1 recorder's mic input, averaging about
10db lower than is ideal for good SN/R, even with the R-1's input volume
set to maximum!

Don't know whether such an animal exists, but I figured this would
be a good place to ask. If a really tiny very portable 10db gain
doohinky thingy doesn't even exist, I'd be open to other suggested
solutions. Thanks much.

An ECM 66 is a DIN output standard mic, so it's unlikely it's the problem.
Although I don't know your recorder. How is it connected to it?

--
*If at first you don't succeed, avoid skydiving.*

Dave Plowman London SW
To e-mail, change noise into sound.

The Opposite Of A 10db Pad
 

Has this lavalier possibly got an ancient 30 or 50 Ohm coil? This could
explain its comparatively low o/p. Don't go and measure it on an analogue
multimeter. If yes, you'll need a step-up, approx 1:3 xformer.

The Opposite Of A 10db Pad
 

In article ,
Jim Gregory wrote:
Has this lavalier possibly got an ancient 30 or 50 Ohm coil? This could
explain its comparatively low o/p. Don't go and measure it on an
analogue multimeter. If yes, you'll need a step-up, approx 1:3 xformer.

Sony were the originator of the small high quality personal mic - the
ECM 50. Dunno what ECM actually stands for, but rumour was electret
condenser mic. And I dunno again if they ever made a moving coil personal
- it doesn't make sense these days given how cheap an electret is.

--
*Money isn't everything, but it sure keeps the kids in touch.

Dave Plowman London SW
To e-mail, change noise into sound.

The Opposite Of A 10db Pad
 

Dave Plowman (News) wrote:
In article ,
Jim Gregory wrote:
Has this lavalier possibly got an ancient 30 or 50 Ohm coil? This
could explain its comparatively low o/p. Don't go and measure it on
an analogue multimeter. If yes, you'll need a step-up, approx 1:3
xformer.

Sony were the originator of the small high quality personal mic - the
ECM 50. Dunno what ECM actually stands for, but rumour was electret
condenser mic. And I dunno again if they ever made a moving coil
personal - it doesn't make sense these days given how cheap an
electret is.

Mental note - get replacement MCE2 for the one I broke last week...


--
We are the keepers of the sacred words: Ni, Pang,
and Ni-wom!

The Opposite Of A 10db Pad
 

Dave and Tim,
Didn't realise it was a Sony tieclip dooberry he was complaining about. As
it's an electret it should give stacks more level than your ordinary 200 Ohm
moving coil, assuming the polarising voltage is there.

Chas, must be it's connected up wrongly.

The Opposite Of A 10db Pad
 

In article ,
Jim Gregory wrote:
Didn't realise it was a Sony tieclip dooberry he was complaining about.
As it's an electret it should give stacks more level than your ordinary
200 Ohm moving coil, assuming the polarising voltage is there.

Chas, must be it's connected up wrongly.

My thoughts too. IIRC, the ECM 66 comes with an XLR output battery pack
that will also accept phantom. If that's been removed - as you would for
radio mic use etc - the amp volts have to be provided by other means. Of
course many recorders do supply the volts needed for an electret mic, but
it's a bit of a grey area, standards wise.

--
*I almost had a psychic girlfriend but she left me before we met *

Dave Plowman London SW
To e-mail, change noise into sound.

The Opposite Of A 10db Pad
 

"Dave Plowman (News)" wrote in message
...
An ECM 66 is a DIN output standard mic, so it's unlikely it's the problem.
Although I don't know your recorder. How is it connected to it?

The ECM 66B has a male XLR connector (you probably knew that!). I'm using a
Shure transformer to convert to a male mini stereophone plug to accomodate
the R-1's mic input.

Cheers,

Charles

P.S. By the way, I gave the ECM66B a healthy knock against a cardboard box
within minutes of bringing the brand new mike home with me. Could that have
damaged it and affected its output level?

The Opposite Of A 10db Pad. It's a 10dB Dab!
 

Chas,
Ah, a xformer! If it is not a 1:1 ratio (used merely for isolation), I hope
the *low* side of the given ratio of your device is used at the *mic* end
(ergo it steps up into channel i/p). So if it's about 1:3.2, can we rename
it a 10dB Dab?
But using this interface seems drastic and unnecessary.
Is the mic cell at adequate voltage and where is it located? Is battery
switchable off/on?
At the other end, I imagine the mini jackplug should be mono if your R-1
recorder has Mono pannable inputs, or dual mono (stereo plug with tip & ring
in parallel), if your recorder has Stereo inputs.
The knock's result remains to be seen or heard, or not.
Jim

The Opposite Of A 10db Pad
 

Charles H. Riggs, III wrote:

Dear fellow audiophiles,

I'm looking for the opposite of a 10db pad for my unidirectional
ECM-66B
lavalier mike. Its output turns out to be quite a bit lower than is ideal
for the Edirol R-1 recorder's mic input, averaging about 10db lower than
is ideal for good SN/R, even with the R-1's input volume set to maximum!


Looking at the spec for this device it seems its microphone input is not
very sensitive (-10dBU), although the spec seems not to distinguish between
the mic and line inputs in this respect. 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.

As it is a very small device I assume a full blown mic pre rather defeats
the object. If you only need another 10dB gain then a transformer as
suggested by others should work OK. Just be aware the input impedance of
the R-1 is quoted at 6K8 so a 3:1 ratio transformer will make this look
like about 750 ohms. This is a little low for a nominal 600 ohm mic but
your ECM-66B is likely to have a much lower output impedance so it should
be OK.

Ian

--
Ian Bell