Anyone here own a Presonus Audiobox USB?

RWhite

Well-known member
I recently bought a Presonus Audiobox USB interface. Two inputs, which are a universal XLR / 1/4" type. I had planned on using it both with two microphones and also with a small 8 channel mixer, plugging the line level outputs of the mixer into the inputs of the interface to do some live 2 channel recording.

Now that I've actually read the manual (note to self: always download and read the manual before buying) it seems to say that these inputs are for microphones or guitars ONLY, not line level devices such as mixers or keyboards. The specific text:

Instrument Inputs (Channels 1 and 2). The TS connector on channels 1 and 2 are for
use with an instrument (guitar, bass, etc.). When an instrument is plugged into the
instrument input, the mic preamp is bypassed, and the AudioBox USB becomes an active
instrument preamplifier.
NOTE: Active instruments are those that have an internal preamp or a line level output.
Active instruments should be plugged into a line input rather than into an instrument input.
Plugging a line level source into the instrument inputs on the front of the AudioBox USB
not only risks damage to these inputs but also results in a very loud and often distorted
audio signal.
(In other words, don’t plug a line level source into the combo jacks of channel 1 or 2.)


Needless to say this sucks, and it looks like I wasted some cash. I was wondering if anyone here had tried using a mixer or keyboard or other such device in their Audiobox USB?
 
No surprise, Guitar Center wont take the unit back, as it is a "non-returnable item". Bummer.... works great with mics for sure, but that's it. Not the unit I was led to believe. Any recommendations on a USB 2.0 interface that does BOTH 2 mics or 2 line inputs?
 
that interface is strange. what if you had a mic that did not use phantom power? I have a few friends who use Presonus interfaces and love them and use them strictly as line level devices.
 
that interface is strange. what if you had a mic that did not use phantom power? I have a few friends who use Presonus interfaces and love them and use them strictly as line level devices.

I've been using it with two Shure SM-57 mics, that don't require Phantom power. It works fine. Phantom power is a seperate switch that can be turned on or off.

My original post could have been worded better. The manual for the Presonus flatly says it is not for use with Line Level devices, and that it will distort - or damage the unit - if you do. When I look at Guitar Center's page I see several comments from users complaining about the unit distorting. My guess is that plenty of people were also told by G.C. salesmen that it worked at line level and they never bothered to read the manual. So my question was to see if anyone who owned one had actually tried it at line level and got it to work OK. Now that I know I can't return the unit, I'll probably try that experiment myself.
 
This might work for you, it should allow you to use your mixer's line outs into the mic inputs on the AudioBox.

Whirlwind Direct2 | Sweetwater.com

Thanks for the suggestion, that does indeed look like it would work. But I hate to throw another $120 at the problem, I don't want to get stuck again if it doesn't work. I'll have to check and see if I can return it first.

If I had not been a dumbass and had done more research I might have gone with the Alesis 102 Express or the Tascam US-144, both of which seem to have the ability to switch between line and mic levels.
 
Just connect the mixer line outs to the mic inputs using XLR plugs. Make sure the mic pre level is turned down and watch the line output level of the mixer is not too high, if fact you should be able to calibrate the input using the mic pre volume knobs on the front.

Also ensure that the phantom is never on so that the fantom does not damage the line outs of the mixer.

This is not perfect but it will work and if you watch the levels there will be no distortion or damage caused.

Alan.
 
Just connect the mixer line outs to the mic inputs using XLR plugs. Make sure the mic pre level is turned down and watch the line output level of the mixer is not too high, if fact you should be able to calibrate the input using the mic pre volume knobs on the front.

Also ensure that the phantom is never on so that the fantom does not damage the line outs of the mixer.

This is not perfect but it will work and if you watch the levels there will be no distortion or damage caused.

Alan.

I wouldn't recommend this. Level is one thing and you might get close but impedance is another. The line out and mic in just aren't gonna work (properly) without some kind of transformation.

I know Alan mentioned checking phantom power but all it takes is one mistake and you've potentially ballsed all your gear.
 
Could get yourself a DI box, which can turn line level or instrument level into mic level, then just plug into your XLR mic inputs on the interface. You can go as cheap as you need with those things too. I have a cheap £30 thing in case I ever need it.
 
I wouldn't recommend this. Level is one thing and you might get close but impedance is another. The line out and mic in just aren't gonna work (properly) without some kind of transformation.

I know Alan mentioned checking phantom power but all it takes is one mistake and you've potentially ballsed all your gear.

An instrument preamp is a relatively high impedance input, so you should be fine running a line output into it once you match the levels. (A line input usually is somewhere around 10k input impedance; an instrument pre can be anywhere from 100k to two or three megohms. Translation: you won't load down the output too much.) For this reason, I would use the instrument input coupled with a pad (which is basically just a pair of resistors wired such that the signal splits two ways, with one resistor sending the output to ground and the other resistor sending the output towards your audio interface.

http://www.uneeda-audio.com/pads/ tells how to design a pad circuit. It's pretty trivial and consists of about a dollar worth of parts, not including the cost of the cable that you have to cut in half. :)
 
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