On some models, the headphones and control room share the same level control; on others, there’s a separate control for headphone level.

Some models have two headphone jacks. The two jacks on the 1642-VLZ PRO are fed from the same point, and both follow the same Phones level control. The 8-Bus console has two completely independent headphone outputs, each having its own level control and source selector for two separate mixes to its headphone jacks.

Studio Output (8-Bus)

The Studio Output normally feeds an amplifier and speakers (or powered speakers) in the studio, so that the musicians can hear a playback without coming into the control room. These carry the same signal as the Control Room outputs, but have an independent level control so you can adjust the playback volume to suit the listeners.

The 8-Bus TALKBACK microphone can be routed to the Studio output, so that you can talk to the players through the studio monitor speakers.

WARNING: When you have mics live in

the studio, they’ll also be live in the studio monitors if the Studio output control is

turned up. In the extreme case, you’ll get feedback, but you don’t want to record the speaker outputs ei- ther. When tracking, be sure to turn the Studio Level control down between playbacks.

The Studio Output jacks can be used with a second amplifier and speakers in the control room, so you can compare the mix on your high grade monitors with the boombox speakers the rest of the world listens to. To switch between the two, turn one level control down and the other one up, or easier, use an external monitor A/B switch.

Mix B Output (8-Bus)

The MIX-B jacks are 1/4" unbalanced outputs that carry the Mix B signal. We’ll cover Mix B in depth later on, but briefly, it’s an independent stereo mix that’s usually used for monitoring the multitrack recorder returns when tracking.

Channel Inserts

The channel INSERT jacks allow you to break the channel signal path right after the mic preamp stage and its associated TRIM control (the low-cut filter too on some mixers) and insert a device such as a compressor, equalizer, or de-esser into the chain.

MIXER ANATOMY: CHAPTER 2

You can also insert a signal processor such as a delay, flanger, or reverb unit in the channel path to process the source coming into that channel. This is sometimes called a “serial” effect hookup since it’s in series with the signal path.

Since most people who need only a small mixer, don’t have racks full of processing gadgets, our smallest mixers don’t have Inserts on every channel. The larger ones do.

The INSERT jack is a 1/4" TRS type, but in this instance, the two jack contacts are used as an output (send) from the preamp and an input (return) back into the remainder of the channel strip. Switch contacts built into the jack provide a “normal” connection from send to return when there’s no plug inserted. When you push a plug all the way in, this connection is broken, and you have access to the channel insert points through the jack.

The tip of the plug connects to the SEND, and the ring connects to the RETURN. Since we’re using only one contact of the jack for each connection, connections to and from the INSERT are unbalanced. The send is a low impedance line-level output that will drive any pro or semi-pro processing device. The RETURN is a moderate impedance line-level input that can be driven by almost any device.

You can buy an Insert cable off the rack at your local music store, or build one. Here’s how it’s wired:

 

ring

 

SEND to processor

tip

(TRS plug)

“tip”

sleeve

 

This plug connects to one of the

“ring”

mixer’s Channel Insert jacks.

RETURN from processor

Tip = Send (Output to effects device)

Ring = Return (Input to effects device)

Sleeve = Common Ground (Shield connects to all three sleeves

Here’s how to hook an outboard signal processor in line with the channel path (a “serial” connection):

RING

 

TIP

 

vu

IN

OUT

 

 

Compact Mixer Reference Guide

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