[genericaudioperson]

Hello,

If you are sending a balanced line-level XLR signal to a mixer that
has XLR mic preamp inputs, and 1/4" line level inputs, what's the
solution?

Can you simply keep the gain very low on the XLR input and run the
cable into the mic preamp input? Or is it better to convert the XLR
to a 1/4" at the end using one of those inline tranformers and sending
the signal into the line input?

Usually the idea of a direct box is to take an unbalanced instrument
signal and balance it for a long cable run. But I'm actually looking
to do the reverse: to take a +4 XLR balanced cable run and step it
down to 1/4" instrument level at the end before going into the mixer.
Is there a direct box that works in reverse like this?

Maybe it's o.k. to simply run straight into the mic preamp and keep
the gain low. But I'm not sure if that makes feedback more of a
problem.

[Laurence Payne[_2_]]

On Sun, 14 Dec 2008 12:20:15 -0800 (PST), genericaudioperson
wrote:

Hello,

If you are sending a balanced line-level XLR signal to a mixer that
has XLR mic preamp inputs, and 1/4" line level inputs, what's the
solution?


An XLR TRS 1/4" jack plug adapter or cable.

[Michael R. Kesti[_3_]]

genericaudioperson wrote:

Hello,

If you are sending a balanced line-level XLR signal to a mixer that
has XLR mic preamp inputs, and 1/4" line level inputs, what's the
solution?

Can you simply keep the gain very low on the XLR input and run the
cable into the mic preamp input? Or is it better to convert the XLR
to a 1/4" at the end using one of those inline tranformers and sending
the signal into the line input?

Usually the idea of a direct box is to take an unbalanced instrument
signal and balance it for a long cable run. But I'm actually looking
to do the reverse: to take a +4 XLR balanced cable run and step it
down to 1/4" instrument level at the end before going into the mixer.
Is there a direct box that works in reverse like this?

Maybe it's o.k. to simply run straight into the mic preamp and keep
the gain low. But I'm not sure if that makes feedback more of a
problem.

The complete story on this and related things is RaneNote #100, Sound
System Interconnection. http://www.rane.com/note110.html

--
================================================== ======================
Michael Kesti | "And like, one and one don't make
| two, one and one make one."
mrkesti at hotmail dot com | - The Who, Bargain

[Scott Dorsey]

genericaudioperson wrote:

If you are sending a balanced line-level XLR signal to a mixer that
has XLR mic preamp inputs, and 1/4" line level inputs, what's the
solution?

Use a cable.

Can you simply keep the gain very low on the XLR input and run the
cable into the mic preamp input? Or is it better to convert the XLR
to a 1/4" at the end using one of those inline tranformers and sending
the signal into the line input?

Is the 1/4" input balanced or unbalanced? If it's unbalanced, do you
really care that the line becomes unbalanced? If it's only a few feet
you probably don't.

Usually the idea of a direct box is to take an unbalanced instrument
signal and balance it for a long cable run. But I'm actually looking
to do the reverse: to take a +4 XLR balanced cable run and step it
down to 1/4" instrument level at the end before going into the mixer.
Is there a direct box that works in reverse like this?

Okay, this is a totally different question. Instrument inputs want
very high-impedance sources and part of the tone of the amp comes
from that. A "Reamp Box" will do that job for you.

Maybe it's o.k. to simply run straight into the mic preamp and keep
the gain low. But I'm not sure if that makes feedback more of a
problem.

Wait, now you're talking about a mike preamp and not about an instrument
amp? What are you really trying to do?
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Mike Rivers]

genericaudioperson wrote:

If you are sending a balanced line-level XLR signal to a mixer that
has XLR mic preamp inputs, and 1/4" line level inputs, what's the
solution?

Is the 1/4" input balanced? Do you want to keep it balanced?

Can you simply keep the gain very low on the XLR input and run the
cable into the mic preamp input?

It depends on the source. Most mic inputs have about a 2.5K impedance,
and most line level sources like to see at least twice that to get their
full headroom without clipping. So if you were to put a pad in between
that's designed to provide a higher impedance on the source side, that
would be a better way to do it than just drop the gain down.

Or is it better to convert the XLR
to a 1/4" at the end using one of those inline tranformers and sending
the signal into the line input?

Insufficient data. See my first question.

Usually the idea of a direct box is to take an unbalanced instrument
signal and balance it for a long cable run. But I'm actually looking
to do the reverse: to take a +4 XLR balanced cable run and step it
down to 1/4" instrument level at the end before going into the mixer.
Is there a direct box that works in reverse like this?

That's usually called a ReAmp box (that's a commercial name). It's
designed to go to a high impedance instrument input from a line level
source. "Instrument level" is in the ballpark of line level but doesn't
usually run as high.

Maybe it's o.k. to simply run straight into the mic preamp and keep
the gain low. But I'm not sure if that makes feedback more of a
problem.

What does feedback have to do with anything? I thought you were running
line level signals, not microphones.

Now, please, what's your REAL question?



--
If you e-mail me and it bounces, use your secret decoder ring and reach
me he
double-m-eleven-double-zero at yahoo -- I'm really Mike Rivers
)

[Richard Kuschel]

On Dec 14, 1:20 pm, genericaudioperson
wrote:
Hello,

If you are sending a balanced line-level XLR signal to a mixer that
has XLR mic preamp inputs, and 1/4" line level inputs, what's the
solution?

Can you simply keep the gain very low on the XLR input and run the
cable into the mic preamp input? Or is it better to convert the XLR
to a 1/4" at the end using one of those inline tranformers and sending
the signal into the line input?

Usually the idea of a direct box is to take an unbalanced instrument
signal and balance it for a long cable run. But I'm actually looking
to do the reverse: to take a +4 XLR balanced cable run and step it
down to 1/4" instrument level at the end before going into the mixer.
Is there a direct box that works in reverse like this?

Maybe it's o.k. to simply run straight into the mic preamp and keep
the gain low. But I'm not sure if that makes feedback more of a
problem.


What are the levels that the 1/4" input jacks designed to see? Are
they balanced?

How do you know that the 1/4" input jacks are designed for instrument
(approx. -20dBV) level ?

What is the length of the run?

What is driving the signal? Mic preamp, mixer, or some other device
such as a keyboard?

Generally, it is a bad thing to throw away any gain that you already
have and then bring it up later. That induces noise at the very least
and distortion at the worst.

If the levels aren't mismatched then use an adapter cable. As long as
you aren't introducing a ground loop that will be the easiest most
likely best solution.

[Richard Crowley]

"genericaudioperson" wrote...
a bunch of seeming unrelated questions before this one...
also not clear what this has to do with "inline tranformer question"?

But I'm actually looking
to do the reverse: to take a +4 XLR balanced cable run and step it
down to 1/4" instrument level at the end before going into the mixer.
Is there a direct box that works in reverse like this?

http://en.wikipedia.org/wiki/Re-amp
There are several commercial products which take line level and
convert them to "instrument level" for exactly this application.

Maybe it's o.k. to simply run straight into the mic preamp and keep
the gain low.

Almost certainly not. It is very doubtful that you can *reliably* crank
the level of a +4 output down to "instrument level" which is something
like 60dB difference or more.

But I'm not sure if that makes feedback more of a problem.

What does "feedback" have to do with this? Is this a reinforcement
situation?

[Richard Crowley]

"genericaudioperson" wrote ...
.... But I'm actually looking
to do the reverse: to take a +4 XLR balanced cable run and step it
down to 1/4" instrument level at the end before going into the mixer.

Can you explain why you want to take +4 line level, knock it down
to -60 instrument level, and then boost it back up to even something
you can feed into the mic input when you already have a perfectly
good line-level input (according to your own description)?

This is quite probably the worst possible solution most of us could
conceive of. If there are some mitigating circumstances here that
make you consider such a bizzare scheme, you didn't mention them.

What exactly are you trying to do here? Some might think you are
just using a random question generator and have no Real-World
applications in mind. (Oh, and a random subject-line as well.)

[Paul Stamler[_2_]]

"genericaudioperson" wrote in message
...
If you are sending a balanced line-level XLR signal to a mixer that
has XLR mic preamp inputs, and 1/4" line level inputs, what's the
solution?

Can you simply keep the gain very low on the XLR input and run the
cable into the mic preamp input? Or is it better to convert the XLR
to a 1/4" at the end using one of those inline tranformers and sending
the signal into the line input?

If the 1/4" line-level input is a TRS jack, it's balanced, and all you need
is an XLR-F/TRS-M adapter.

If the 1/4" line-level input is a TS jack, things are more difficult. One
solution, not necessarily a good one, is to make an adapter which connects
pin 2 of the XLR to the tip of a TS plug, pin 1 to the sleeve of the plug,
and pin 3 to a 10k resistor the other end of which is connected to the
sleeve. (I'm assuming, going with the percentages, that your balanced signal
is electronically balanced, not transformer-coupled. If it's
transformer-coupled it's a different story, but it probably isn't.)

A better solution is to use a good-quality 1:1 line-level transformer and
connect it between the XLR connector and the TS jack. That preserves
common-mode rejection. You can get one from Jensen. It'll cost ya, though.

A decent solution is to use a good-quality DI box to step the line-level
signal down to mic level, then run it through the mic preamp. It has to be a
good one, though; you can make one from a Jensen mic transformer. It'll cost
ya, too.

A horrible solution is to run it into the mic preamp by itself, unless you
have a very unusual mic preamp on your mixer.

Usually the idea of a direct box is to take an unbalanced instrument
signal and balance it for a long cable run. But I'm actually looking
to do the reverse: to take a +4 XLR balanced cable run and step it
down to 1/4" instrument level at the end before going into the mixer.
Is there a direct box that works in reverse like this?

Not to my knowledge. But that doesn't matter, because your 1/4" input isn't
at instrument level anyhow; it's a line-level input. You said so.

Maybe it's o.k. to simply run straight into the mic preamp and keep
the gain low. But I'm not sure if that makes feedback more of a
problem.

Well, once the mic preamp is into massive clipping, it'll compress the hell
out of the signal, so I suppose it might be more likely to feed back. But
that'll be the least of your worries.

Peace,
Paul

[Mike Rivers]

Richard Crowley wrote:

Can you explain why you want to take +4 line level, knock it down
to -60 instrument level

Not to start a side discussion here, but "instrument level" for most of
what we consider "instruments' in this context (guitar and bass pickups)
is just a little lower than what most of us consider "line level." A hot
guitar pickup, with the guitar strummed hard, can put out a good solid
+6 dBu, with peaks 10 dB or more above that.

The difference between an "instrument" input and a 1/4" line level jack
is typically not in gain, but rather, in impedance. And instrument
inputs, unless they have an input transformer, are never balanced. But
you knew that.



--
If you e-mail me and it bounces, use your secret decoder ring and reach
me he
double-m-eleven-double-zero at yahoo -- I'm really Mike Rivers
)

[Richard Crowley]

"Mike Rivers" wrote ...
Richard Crowley wrote:
Can you explain why you want to take +4 line level, knock it down
to -60 instrument level

Not to start a side discussion here, but "instrument level" for most of
what we consider "instruments' in this context (guitar and bass pickups)
is just a little lower than what most of us consider "line level." A hot
guitar pickup, with the guitar strummed hard, can put out a good solid +6
dBu, with peaks 10 dB or more above that.

The difference between an "instrument" input and a 1/4" line level jack is
typically not in gain, but rather, in impedance. And instrument inputs,
unless they have an input transformer, are never balanced. But you knew
that.

Does the OP know *any* of that? I'm beginning to suspect
another troll here.

[Mike Rivers]

Richard Crowley wrote:

Does the OP know *any* of that? I'm beginning to suspect
another troll here.

Probably not, but not everyone who doesn't know fundamentals is a troll.
I suspect that he has heard the terms, knows that some units have an
"instrument" input, and just didn't ask the right question. It happens
all the time. You can either stand by the sideline and wait to see if
the real problem emerges, or try to squeeze enough information
(including what he really has and wants to accomplish) to give him a
useful answer.

That's my approach, most of the time. But not always. I'm not a saint.


--
If you e-mail me and it bounces, use your secret decoder ring and reach
me he
double-m-eleven-double-zero at yahoo -- I'm really Mike Rivers
)

[genericaudioperson]

Wow, I didn't realize my question left so many unanswered questions!

The scenario is this:
you have a submixer. then you want to send the balanced +4 xlr outputs
to the main mixer (with about a 40 foot cable run). the main mixer
has two choices:
1) xlr mic pre inputs
2) 1/4" line level inputs (which I'm guessing are unbalanced).

So I guess the ideal situation would be to keep the cable run balanced
all the way to near the mixer, and then use a converter box to step it
down to 1/4" unbalanced at the last minute.

I'm not getting appreciable clipping running the xlr signal into the
main mixer preamp inputs.. But I wasn't sure if doing this is making
the system more susceptible to feedback (by having too much gain
before the power amp stage).

this must be a common enough scenario that there is a standard box to
make things the right way electronically.

[Chris Hornbeck]

On Mon, 15 Dec 2008 18:15:40 -0800 (PST), genericaudioperson
wrote:

Wow, I didn't realize my question left so many unanswered questions!

The scenario is this:
you have a submixer. then you want to send the balanced +4 xlr outputs
to the main mixer (with about a 40 foot cable run). the main mixer
has two choices:
1) xlr mic pre inputs
2) 1/4" line level inputs (which I'm guessing are unbalanced).

Why unbalanced? But more importantly, why guess? What is this
mysterious "main mixer"?

CH

[Scott Dorsey]

genericaudioperson wrote:
Wow, I didn't realize my question left so many unanswered questions!

The scenario is this:
you have a submixer. then you want to send the balanced +4 xlr outputs
to the main mixer (with about a 40 foot cable run). the main mixer
has two choices:
1) xlr mic pre inputs
2) 1/4" line level inputs (which I'm guessing are unbalanced).

I would find out if they are balanced or not, and I would NOT guess.

So I guess the ideal situation would be to keep the cable run balanced
all the way to near the mixer, and then use a converter box to step it
down to 1/4" unbalanced at the last minute.

You can use a transformer box to balance or unbalance the line, but
I'd first make sure you don't have a balanced 1/4" input to begin with.

I'm not getting appreciable clipping running the xlr signal into the
main mixer preamp inputs.. But I wasn't sure if doing this is making
the system more susceptible to feedback (by having too much gain
before the power amp stage).

Well, are the main inputs really mike inputs, or is this something like
a Mackie where there is a very wide range of usable gain?

this must be a common enough scenario that there is a standard box to
make things the right way electronically.

Everybody should have some 1:1 transformer boxes in the closet, but
good ones aren't cheap and cheap ones usually aren't very good. These
days since just about everything has electronically balanced inputs
and outputs they aren't as important. But see, you don't even mention
things like what kind of consoles you're using.

And I'm STILL trying to figure out what any of this has to do with
instrument level connections, which is what you seemed to be talking
about in your first posting.

Really, you need the Yamaha Sound Reinforcement Handbook.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Richard Crowley]

"genericaudioperson" wrote in ...
Wow, I didn't realize my question left so many unanswered questions!

The scenario is this:
you have a submixer. then you want to send the balanced +4 xlr outputs
to the main mixer (with about a 40 foot cable run). the main mixer
has two choices:
1) xlr mic pre inputs
2) 1/4" line level inputs (which I'm guessing are unbalanced).

Why do you have to guess?
Do you not know what kind of mixer it is?
Perhaps you are learning from your last several questions that
details are important, and frequently *critical*. You will always
get more complete and more useful answers if you reveal the
exact make and model of the equipment you are asking about.
And the actual names of the connectors, etc, and what kind
of cable (and connectors) you are using, etc.

In many mixers (like Mackie, et.al.) the balanced line input
goes through an internal pad into the balanced mic input, so
the line input is fully balanced.

So I guess the ideal situation would be to keep the cable run balanced
all the way to near the mixer, and then use a converter box to step it
down to 1/4" unbalanced at the last minute.

If you have a line-level source and a line-level input, no "step-
down" is necessary.

A 40-foot run for a balanced line-level signal is *nothing*. Condider
that the first "line-level" runs were miles long (Al Bell's original
telephone
system.) And in more recent times balanced line-level runs even
hundreds of miles are not unknown. Remember that telephone and
radio network signals went coast-to-coast on pairs of wires until
less than 50 years ago with the advent of communication satellites.

I'm not getting appreciable clipping running the xlr signal into the
main mixer preamp inputs.. But I wasn't sure if doing this is making
the system more susceptible to feedback (by having too much gain
before the power amp stage).

You might get away with it if you're lucky, but you're living on the
edge and there is no good reason to do that. The proper cable and/
or connector adapters are dirt-cheap. The potential of feedback is
not particularly an issue unless you don't keep the output of the source
unusually low (because you are feeding a line-level source into a mic-
level input).

this must be a common enough scenario that there is a standard box to
make things the right way electronically.

A line-level source to a line-level input usually doesn't typically require
ANY kind of "box", just an appropriate cable and connectors.

[Laurence Payne[_2_]]

On Mon, 15 Dec 2008 18:15:40 -0800 (PST), genericaudioperson
wrote:

you have a submixer. then you want to send the balanced +4 xlr outputs
to the main mixer (with about a 40 foot cable run). the main mixer
has two choices:
1) xlr mic pre inputs
2) 1/4" line level inputs (which I'm guessing are unbalanced).

Don't guess, find out. If they ARE balanced, you can ignore the
smokescreen and follow my original simple suggestion.

[Mike Rivers]

genericaudioperson wrote:
Wow, I didn't realize my question left so many unanswered questions!

That's what happens when you ask too general or hypothetical question.
The best answer, and the tradeoffs (there are always tradeoffs) depend
on the application as much as on the question.

you have a submixer. then you want to send the balanced +4 xlr outputs
to the main mixer (with about a 40 foot cable run). the main mixer
has two choices:
1) xlr mic pre inputs
2) 1/4" line level inputs (which I'm guessing are unbalanced).

Would this 'you' be YOU?

First off, don't guess about the 1/4" line level inputs. Either find out
or simply assume that they're unbalanced. For a 40 foot run, it would be
smart to run a balanced connection.


So I guess the ideal situation would be to keep the cable run balanced
all the way to near the mixer, and then use a converter box to step it
down to 1/4" unbalanced at the last minute.

Yup. But since it's line level from the submixer and you're going into a
line level input on the main mixer, you need to use a 1:1 transformer,
not a "mic adapter" transformer. This is a pretty common item.

I'm not getting appreciable clipping running the xlr signal into the
main mixer preamp inputs..

You're just not trying hard enough. g But sometimes this indeed works
out OK sometimes. But it depends on the power available from the source
and the load impedance of the mic input. In the case of Mackie mixers
that have a Mic/Line level switch for the main XLR ouptuts, the
attenuator that goes in line when in the Mic level position provides
enough isolation from the low impedance load so that it doesn't affect
the output stage of the mixer.

But I wasn't sure if doing this is making
the system more susceptible to feedback (by having too much gain
before the power amp stage).

Since you're reducing the gain by lowering the output of the submixer
and/or lowering the gain of the preamp, you don't have too much gain.

this must be a common enough scenario that there is a standard box to
make things the right way electronically.

It's not all that common, because of all the permutations of input and
output connectors, but if you're willing to accept one or two adapters
there are a number of relatively inexpensive choices. The Ebtech
(Morely) Hum Eliminator is OK if you dont run the output of the submixer
too hot. Jensen makes a whole line of transformers in many
configurations for considerably more money, but they don't crap out when
the levels get high. Sescom has some as well.




--
If you e-mail me and it bounces, use your secret decoder ring and reach
me he
double-m-eleven-double-zero at yahoo -- I'm really Mike Rivers
)