Connecting external preamp to the mbox pro 3

[qipi]

Hi, I wish to connect the "Pro MPA-II" preamp to the Mbox pro
How do I do that - bypassing the built-in preamps?

I understood that it should be through the line-in? if so, how should I
make all the connections?


Thank you!

[guatamas]

The way I have my setup is through a patchbay, if I want to use my Pro VLA II, I send the signal, say a stereo drum bus track to the outputs of 5-6 or if its a mono track just 1 output (outs 1-4 are for my monitors) of the mbox pro (in the control panel the faders are up for outs 5-6) to the inputs of the VLA, adjust settings and take the outputs of the VLA back to the line inputs of the mbox. Of coarse all of this is done through a patchbay where all of the I/O are connected through the back of the patchbay and I just patch through the front. But this can be compared to what you want to do, when using line level devices always use line inputs because there is a risk of damaging the preamps of the mbox. The point of mic/DI is to bring those singnals up to line level, your MPA does this, that is a purpose of a preamp.

So what do you want to do? Use the MPA while tracking a vocal or instrument?

You'll need 2 TRS or XLR cables to do this or just 1 if your only tracking a mono source:
1 (or 2) output(s) of the MPA to line inputs of the mbox, connect the mic/DI to your MPA, adjust the settings, adjust Master volume so you don't clip going into Pro Tools and engage the buttons on the front of the mbox to receive line in. In pro tools select the right inputs of the mbox and just hit record

If you want to use the MPA or another signal processor as an insert (like a plugin) this requires a slightly different cabling setup

[albee1952]

Feed the ART unit into the LINE inputs(3 and 4). Do NOT patch the preamp to the XLR inputs as they are MIC level(and the preamp is sending LINE level). Balanced cables are best.

[Bill Denton]

Sorry, guatamas...but do you really think somebody who does not yet know how to connect a preamp needs to get involved with patchbays and such? I know you meant well, but it's best to match the advice to the audience...

Now...to the OP...here's how you do it...

Obtain two cables with 1/4" TRS (tip/ring/sleeve) connectors on both ends. These are called balanced cables, and the connectors shoule look like the 1/4" connector on a pair of stereo headphones. The cables should each be long enough to reach from the Pro MPA-II to the Mbox Pro.

On the rear of the Pro MPA-II, plug one end of each cable into each of the 1/4" balanced outputs (one cable plugged into Channel 1, the other cable plugged into Channel 2).

Locate the cable that is connected to Channel 1 on the Pro MPA-II and plug the other end into Line Input 3 on your Mbox Pro.

Locate the cable that is connected to Channel 2 on the Pro MPA-II and plug the other end into Line Input 4 on your Mbox Pro.

(By convention, odd numbered inputs/outputs are used for the left stereo channel, even numbered inputs/outputs are used for the right stereo channel.)

Ensure that the +4/-10 switch adjacent to Line Inputs 3 & 4 on your Mbox Pro is in the out position, for +4 dBu.

You will not be adjusting any "input levels" on the Mbox Pro, you will make all adjustments on the Pro MPA-II.

The manual for the Pro MPA-II contains very good instructions for its operation...I recommend you read and follow them.

When recording in Pro Tools (or any other DAW), you will want to adjust the Output Level and/or the Master Output Level control(s) on the Pro MPA-II so the level meter on the audio track you are recording reads an average of around -18 DBFS.

Good luck...

[guatamas]

Don't use XLR, that's my mistake. Use TRS instead

[nst7]

One important thing, after you've done what Bill said - Make sure that the "mic/line button on the front of the unit is pressed IN, for Line.

[qipi]

You really covered it all up.

I am not used to this kind of detailed answers :)


10X!!!