How its possible ? Anyone could explain to me? Mic to Line to Mic on my 411/400a

Hiro Nakamura

Active member
Hi guys,

I did a gig for an event shoot.
I am sure that you guys have done this many times.
The director wants a clean audio feed from the sound desk from the event audio department.
I normally go with a XLR cable, but this time I was quite mobiled ... cameraman would like to run around the tables.

So... I made a short cable from my UM400a to XLR, plugged straight in to the soundman,
and I switched my SD 302 to LINE input, and output to a wireless hop MIC level to the camera.

It was a sucessful shoot.

What doesn't make sense to me is the UM400a supposed to take MIC level transmition, like those country B3 and B6, are all MIc level.

So.. when I plugged my UM400a to the sound board, which provided LINE input to it... and at the beginning... it's away to hot but after I switched my SD302 to Line input, it sounded fine... not clipping or anything....

How could be possible? I wanna find out from the technical prospective.

Any inputs are highly appreciate !!!

Thanks in advance

Hiro
 
I think the reason nobody has answered is that it's a bit hard to understand your audio chain from the information posted...

Let's see if I can track this, you were shooting and you needed a direct audio feed from the live soundman, yes? But because you needed "no cable" for some reason (mobility?), you sent a signal from the soundboard to your Lectro wireless, your wireless into your Sound Devices mixer, and your mixer to the camera, is that it? Thereby giving you a wireless feed from the soundboard, and you want to know why it worked(?)...

One would think that there might be some distortion or signal/impedance issues from your Line to Mike, Mike to Line set-up; did you adjust the input level on the mixer? Are you sure that the soundman was feeding you a balanced line-level signal?

In any event, it worked. Go with it, you have a new solution in your bag of tricks!

GJ
 
What doesn't make sense to me is the UM400a supposed to take MIC level transmition, like those country B3 and B6, are all MIc level.

A 5-pin input jack provides taps for low impedance dynamic mics, electret lavalier mics with positive or negative bias and line level inputs.
http://www.lectrosonics.com/Transmitters/um400a.html

You did not provide the critical detail of exactly HOW you "made a short cable from my UM400a to XLR", but apparently you wired it correctly for line-level input.

You also omitted the details about the receiving end. Wireless receivers can have line-level and/or mic-level outputs.

So both of your questions, about the transmitting end, and the receiving end likely have logical explanations, but you did not provide enough details to confirm the scenario.
 
Sorry for failing to explain my scenario.
Let me try one more time.
1. Soundboard feed out TO my UM400a (a sound guy was in charge of it, I just went in front of him asked for a feed. so ... he told me if I have a xlr cable, and the feed would be a line level.
2. cable from the soundboard to my UM400a is a TA5F to XLR like the pix?? 16.jpg
I was not sure if the um400a could take Line input, but I did it that way.
3. The UCR 411 to my SD302 with a Line Level input selected on the mixer.

My theory is that UM400a not supposed to be able to take Line Level and transmit the Line level signal wirelessly to UCR411.
It should be clipping sound all the way... but it went well with the Line level.
I didn't even adjust the audio level on the UM400a after I unplugged a B3 mike.

I am trying to understand that the UM400a, plug a mike (B3) or plug a Line level input cable, it produces the audio level, which is not clipping.... WHY?
Theoretically, the Line level is much higher than the Mike level, which should make the audio clip....
I hope you could get my point, which I am trying to understand....?

Hiro
 
2. cable from the soundboard to my UM400a is a TA5F to XLR like the pix

We all know what a TA5F and a female XLR look like. The photo doesn't tell us anything.
What we DON'T know (and apparently you don't know, either) is...
1) WHERE did that cable come from? It didn't just fall from the sky. Did it come with the um400a?
2) Is that cable intended to be a line-level cable? Is it intended to be a mic-level cable?
2) HOW is that cable WIRED? Specifically is it wired for line-level?

I was not sure if the um400a could take Line input, but I did it that way....
My theory is that UM400a not supposed to be able to take Line Level and transmit the Line level signal wirelessly to UCR411....
It should be clipping sound all the way... but it went well with the Line level.

The UM400a is designed to take line-level. Did you miss the quote from Lectrosonics website?

I didn't even adjust the audio level on the UM400a after I unplugged a B3 mike.

The "adjustment" is made IN THE CABLE. You apparently used a line-level cable, so it AUTOMATICALLY made the "adjustment".

I am trying to understand that the UM400a, plug a mike (B3) or plug a Line level input cable, it produces the audio level, which is not clipping.... WHY?

Note that there are FIVE pins on the input connector. Some are for mic level, some are for mic power, and one is for LINE LEVEL. Which one you get depends on how the cable is wired. That is why I keep asking about the cable.

3. The UCR 411 to my SD302 with a Line Level input selected on the mixer.

The UCR411 receiver can put out anything from mic level to line level as you need.

Audio output: Rear panel XLR connector; can drive 600 Ohm, adjustable from -50 to +5 dBu in 1 dB steps (into nominal 10 k bal. load)
http://www.lectrosonics.com/images/TD-sheets/ucr411atd.pdf

Perhaps this is a good opportunity to study the descriptions and operating instructions for your equipment and learn to understand what they are saying. If you have questions about what something means, don't hesitate to come here and ask for help understanding them. Please give a direct reference to what you are asking about, not just an isolated quote, because very often the context is very important to understanding the meaning.
 
Thanks Richard,

Good to know the um400a can actually take line level inputs.
The cable made by a friend of mine who works as all kinds of cabling in an electric shop.

I have to admit that I am lacking of the audio knowledge.
Will keep learning.

Thanks
 
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