Adrian wrote:

Hi,

Can anyone recommend a stereo audio mixer? The immediate and primary
purpose of the same will be to mix the output from three microphones.
It will be good if I had the ability to direct the output one or both
output channels.

The need is to record small public meetings commencing with some live
music (piano) followed by a talk.

However, at some point I would like to be able to mix turntable and
line inputs at home. It seems wasteful to buy two mixers when one
might suffice. For this secondary purpose I need two turntable inputs
and/or two or three line inputs. Switchable turntable/line inputs
would be acceptable.

Output will be to a Behringer UCA202 and a Notebook computer.

Many thanks for your input to my thought process!

Adrian

I feed a Behringer UB1204-PRO directly into a Dell notebook mic jack,
which remarkably doesn't seem to mind it, at low volume.

It seems like a nice mixer, though I prefer the older and now-unavailable
models with the wall wart power supplies, as they generate less RFI
than the newer switching supply ones. But it doesn't matter, if you
don't use them right next to radios.

It doesn't seem to come with a wiring diagram, so you're left extrapolating
from older models that do come with them, as to what goes through what control
to where.
--


On the internet, nobody knows you're a jerk.

On Aug 31, 12:53 pm, Ron Hardin wrote:
Adrian wrote:

Hi,

Can anyone recommend a stereo audio mixer? The immediate and primary
purpose of the same will be to mix the output from three microphones.
It will be good if I had the ability to direct the output one or both
output channels.

The need is to record small public meetings commencing with some live
music (piano) followed by a talk.

However, at some point I would like to be able to mix turntable and
line inputs at home. It seems wasteful to buy two mixers when one
might suffice. For this secondary purpose I need two turntable inputs
and/or two or three line inputs. Switchable turntable/line inputs
would be acceptable.

Output will be to a Behringer UCA202 and a Notebook computer.

Many thanks for your input to my thought process!

Adrian

I feed a Behringer UB1204-PRO directly into a Dell notebook mic jack,
which remarkably doesn't seem to mind it, at low volume.

It seems like a nice mixer, though I prefer the older and now-unavailable
models with the wall wart power supplies, as they generate less RFI
than the newer switching supply ones. But it doesn't matter, if you
don't use them right next to radios.

It doesn't seem to come with a wiring diagram, so you're left extrapolating
from older models that do come with them, as to what goes through what control
to where.
--


Thanks Ron,

I have located the more recent Xenyx 1204, which seems to fit the bill
very well.

Adrian

Adrian wrote:
Thanks Ron,

I have located the more recent Xenyx 1204, which seems to fit the bill
very well.

You'll also need a bunch of 3.5mm to 1/4" adapters, in various combinations
of stereo and mono, and a couple for RCA as well.

Then you'll find you get enormous AC hum when you connect to your computer,
owing to a ground loop. Put a Radio Shack ground loop isolator in that line
(cat 270-054). I keep a bunch of them around to isolate every different thing
that's plugged in on AC mains.
--


On the internet, nobody knows you're a jerk.

Ron Hardin wrote:

Adrian wrote:
Thanks Ron,

I have located the more recent Xenyx 1204, which seems to fit the bill
very well.

You'll also need a bunch of 3.5mm to 1/4" adapters, in various combinations
of stereo and mono, and a couple for RCA as well.

Then you'll find you get enormous AC hum when you connect to your computer,
owing to a ground loop. Put a Radio Shack ground loop isolator in that line
(cat 270-054). I keep a bunch of them around to isolate every different thing
that's plugged in on AC mains.

Oh, and finally some brush-on Deoxit, to keep the adapters working. I get mine
here http://www.partsexpress.com/pe/showd...number=341-215

A tiny bottle lasts forever. It fixes everything, from battery charger terminals
to audio connectors to mains plugs on high current devices that get hot (plug in
and out until the contacts come out clean).
--


On the internet, nobody knows you're a jerk.

On Sep 4, 5:36 am, Ron Hardin wrote:
Ron Hardin wrote:

Adrian wrote:
Thanks Ron,

I have located the more recent Xenyx 1204, which seems to fit the bill
very well.

You'll also need a bunch of 3.5mm to 1/4" adapters, in various combinations
of stereo and mono, and a couple for RCA as well.

Then you'll find you get enormous AC hum when you connect to your computer,
owing to a ground loop. Put a Radio Shack ground loop isolator in that line
(cat 270-054). I keep a bunch of them around to isolate every different thing
that's plugged in on AC mains.

Is that true even if I utilize the USB link into my Notebook?

Oh, and finally some brush-on Deoxit, to keep the adapters working. I get mine
herehttp://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=341-215

A tiny bottle lasts forever. It fixes everything, from battery charger terminals
to audio connectors to mains plugs on high current devices that get hot (plug in
and out until the contacts come out clean).
--
Thanks, I will check this out.

Adrian

Adrian wrote:
Then you'll find you get enormous AC hum when you connect to your computer,
owing to a ground loop. Put a Radio Shack ground loop isolator in that line
(cat 270-054). I keep a bunch of them around to isolate every different thing
that's plugged in on AC mains.

Is that true even if I utilize the USB link into my Notebook?

Yes, it's a problem in the connecting audio cable. The computer and the audio components
don't have quite the same idea of what ground potential is. The slight difference is made up
by a current down the ground shield of the audio cable. There's a slight voltage drop
across the shield as a result, and this voltage drop is shared with the audio input circuit.

So you hear the slight ground difference in the audio signal, as AC hum.

An isolation transformer breaks the ``DC'' path in the audio cable, so there is no
shared current between power and audio circuits.

No hard trying it without, but if you get a hum, that's why.

--


On the internet, nobody knows you're a jerk.

Ron Hardin wrote:

Adrian wrote:
Then you'll find you get enormous AC hum when you connect to your computer,
owing to a ground loop. Put a Radio Shack ground loop isolator in that line
(cat 270-054). I keep a bunch of them around to isolate every different thing
that's plugged in on AC mains.

Is that true even if I utilize the USB link into my Notebook?

Yes, it's a problem in the connecting audio cable. The computer and the audio components
don't have quite the same idea of what ground potential is.

That's the traditional reason for 'hum loops'.

In this case the problem is made worse but the use of switching power supplies (certainly in the
computer) and in some audio gear (I'm fairly certain the Behringer model mentioned also has one).
These swiching power supplies have filters on the ac power input that injects a noise current
into the ground conductor. This messes up your grounding arrangements very effectively.

Graham