female 3.5mm to dual female RCA

[Walter Harley]

I'm going to buy another 3.5mm jack for my adaptor and do a better
soldering. Now that I take a closer look at it, it's not so great.
Thinking about, I remember the tabs getting too hot because the tabs were
moving back-and-forth in the plastic core. I'm going to be more careful
this time.

Hopefully that will fix the problem. If not I'll try a repair shop or
Radio Shack and see what they have to say.

Based on everything you said - I suspect the problem is just a combination
of inappropriate preamp and defective soldering.

Rather than doing all this soldering, you might consider just purchasing
ready-made adapters. But don't do that until you have the mic preamp,
because what you need will depend on the connectors on the preamp; if you
get the right thing you might not need any adapters at all.

I'm inferring the mic you have is something like the Philips/Magnavox
PM62080 "Universal Mic", as shown at
http://www.gemini-usa.com/a5/modelDetail.asp?PkgID=370080&User=GemAudioAccessories.
This mic has what we'd call a "high impedance unbalanced" output. That is
different than most professional mics, which use "low impedance balanced"
outputs. That means that a typical mic preamp will *NOT* work properly with
it. The giveaway is that most mic preamps have "XLR" (three-pin)
connectors, rather than 1/4" mono connectors. You could build an adapter
but it wouldn't get you anywhere, because the signal levels are different.

It is hard to find preamps for this kind of microphone. Your best bet is
probably going to be to find a consumer-grade "mic mixer", even though you
aren't actually mixing anything. For instance, an excellent choice would be
the Radio Shack 32-2056:
http://www.radioshack.com/product.asp?catalog_name=CTLG&product_id=32-2056.
This has 1/4" mono inputs for the mic (meaning it is intended for exactly
your kind of microphone); it has stereo RCA outputs, so you don't even need
to buy any adapters; and it can run on a 9V battery. It lists for $40. You
might also be able to find something like it cheaper somewhere else.
Another possibility would be to find a DJ mixer.

If any of that is unclear, let me know.

 

[Rich Grise]

I put together a adaptor cable to go from the 3.5mm microphone jack to
the dual RCA ends. I think it may be from here where I am getting the
static/hum/noise. It seems that if it is held right the noise is pretty
much gone. Maybe poor solder or bad connection to the tail of the
microphone jack (ground).

Please be more specific.

Are you getting Static?

Are you getting Hum?

Are you getting Noise?

In the realm of electronics, these are three different things. Saying "I
have noise" is so vague as to be meaningless. A baby crying in the
background? An airport? Scratchy sounds when you move the microphone
around? A constant hum? A constant buzz? The sound of rainfall? What are
you trying to record?

Please answer these questions before we even get to the connector-type and
signal-level stuff.

Thanks!
Rich

 

[Rich Grise]

Based on everything you said - I suspect the problem is just a combination
of inappropriate preamp and defective soldering.

From what I've been able to glean, it sounds like he's trying to put a
mono mic into right and left of a stereo preamp simultaneously, in which
case he has "The Jack" wired wrong. All three center conductors should be
connected, and all three shells should be connected, and if there's a
third contact on any of them, it's the wrong part.

The thing he's trying to make is called a "Y-adapter".

Good Luck!
Rich

 

[Pasquale]

The mic is a Phillips P72080, essentially the same.
http://www.gemini-usa.com/a5/modelDetail.asp?PkgID=370076&User=GemAudioAccessories

I also have a XLR microphone that is probably 11 - 12 years old in
excellent condition. It is a Electro-Voice MC100 that is dynamic,
directional, low impedance. I couldn't find any info about it on their
web site. Probably because it is so old. I did find the sheet with specs
and info that came with it.
I didn't use it originally because I was going to RCA's on my A/V cable.
I would like to use the MC100 because I believe it is a better
microphone. I just need to find a set up that will allow me to use it
with a pre-amp out to the A/V cable. I'll try Radio Shack and then some
music shopss, and see if I can find what I need.

What's the difference between Directional and Uni-directional? Is one
better than the other?

Thanks for all your help and suggestions!

 

[Pasquale]

The mic is a Phillips P72080, essentially the same.
http://www.gemini-usa.com/a5/modelDetail.asp?PkgID=370076&User=GemAudioAccessories

I also have a XLR microphone that is probably 11 - 12 years old in
excellent condition. It is a Electro-Voice MC100 that is dynamic,
directional, low impedance. I couldn't find any info about it on their
web site. Probably because it is so old. I did find the sheet with specs
and info that came with it.
I didn't use it originally because I was going to RCA's on my A/V cable.
I would like to use the MC100 because I believe it is a better
microphone. I just need to find a set up that will allow me to use it
with a pre-amp out to the A/V cable. I'll try Radio Shack and then some
music shopss, and see if I can find what I need.

What's the difference between Directional and Uni-directional? Is one
better than the other?

Just curious, how much dB gain do you think you can get from a 2.5W or
10W mic pre-amp?

Thanks for all your help and suggestions!

 

[Walter Harley]

I also have a XLR microphone that is probably 11 - 12 years old in
excellent condition. It is a Electro-Voice MC100 that is dynamic,
directional, low impedance. I couldn't find any info about it on their web
site. Probably because it is so old. I did find the sheet with specs and
info that came with it.

Yes, I'm sure that would be better sounding. You would need a mic preamp
for it. Something along the lines of the Rolls MP13 (Google for it) or an
equivalent. Then, you would come out of the 1/4" output, using a mono 1/4"
to dual RCA adapter from Radio Shack; and from there to the camcorder.

What's the difference between Directional and Uni-directional? Is one
better than the other?

Both of them are imprecise terms, too vague to tell apart.

Microphones are generally classified as "omnidirectional", "cardioid",
"supercardioid", "hypercardioid", or "figure-of-8". These refer to
different amounts and patterns of directionality, where "omnidirection"
means that it is about equally sensitive in all directions, and
"figure-of-8" is just what it sounds like.

What you have is somewhere in the spectrum of cardioid patterns, but there's
no way to tell which one other than by trying.

Directional mics do still pick up a bit of sound from the "off axis" -
particularly at low frequencies. So it's just an approximation.