Henry Engineering SIXMIX User Manual

TM

SixMix

PROFESSIONAL BROADCAST CONSOLE WITH USB DIGITAL AUDIO

1.0 DESCRIPTION

The SIXMIX is a full-featured broadcast station audio mixing console. It features inputs for 2 microphones and 7
stereo line sources, plus an integrated USB audio codec for use with a computer. There is a stereo Program
mixing bus, a Mix-Minus output, Cue bus with Cue speaker, and comprehensive Headphones and Monitor systems.
Other features include Talkback, Guest Headphone facilities, and accurate audio level metering. SIXMIX is ideally
suited for use in a broadcast studio, news room, radio automation system, remote broadcast facility, emergency
studio, internet broadcast station, or editing suite. It is a compact yet versatile and powerful audio production tool.

2.0 INSTALLATION

Read this entire section before
designed for use in broadcast stations and similar professional installations. Some aspects of the
installation require technical expertise. If you do not fully understand the installation instructions, you
should employ the services of an experienced audio engineer or broadcast technician. Damage caused by
incorrect installation or use is not covered by the warranty.

2.1 OPTION PROGRAMMING-WARNING: Disconnect from AC power before removing the bottom cover.

Before

installing the console, read Sections 2.1.1 and 2.1.2 below. Programming jumpers may need to be changed
which requires removing the bottom cover from the console. It is much easier to do this before the console has
been installed and wired. To remove the console bottom cover, first disconnect the console from AC power.
Then invert the console, remove the three screws on each side of the console chassis and lift off the cover.

2.1.1 MONITOR MUTE PROGRAMMING

The SIXMIX Monitor system can be programmed so that when Mic 1 and/or Mic 2 are on, the audio output from the
Monitor system is muted. The console is normally shipped with both Mic 1 and Mic 2 muting turned ON. To change
the Monitor Mute programming, remove the bottom cover of the console to acess the Monitor Mute programming
jumpers. There are two jumpers on the PC board, labeled MIC 1 MUTE and MIC 2 MUTE (JP1 and JP2). To turn
off Mic 1 muting, set JP1 to OFF. To turn off Mic 2 muting, set JP2 to OFF.

2.1.2 MIX-MINUS CHANNEL SELECTION

A telephone “hybrid” device must be used to broadcast telephone conversations or to record phone calls.
The hybrid’s Caller Audio output is fed into one of the SIXMIX console’s input channels. The SIXMIX Mix-Minus
output is fed BACK to the hybrid’s Send input, so the caller can hear the main Program mix. The Mix-Minus output
contains the Program bus mix, minus

For proper hybrid and Mix-Minus operation, the hybrid must
The SIXMIX console is normally configured so the Caller audio is fed into Line Channel 3 (use input 3A or 3B).

However, if Mic Channel 2 will NOT be used for a microphone, the hybrid can be connected to Channel 2, saving
Channel 3 for another (stereo) line level source. To use Channel 2 for the hybrid, the Mix-Minus output must be
changed so it subtracts Channel 2 audio from the Program bus mix. To make this change, locate jumpers labeled
MM SOURCE on the PC board (JP3 AND JP4). Move BOTH jumpers to the CH2 position. The hybrid’s “caller”
audio can now be fed into Mic Channel 2. Use the regular Mic 2 (XLR) input jack if the hybrid audio output is at mic
level. If the hybrid output level is at line level, use the Mic 2 Process Insert jack. Use a TRS plug, and wire the
hybrid audio to the RING; connect the sleeve to ground. Leave the TIP unconnected.

2.1.3 MAINS VOLTAGE SELECTION-WARNING: Disconnect console from AC power before continuing.

SIXMIX is factory-set for use with 115 Volt AC mains. For 230 Volt AC operation, remove
E16+E18, and between E17+E19. Install ONE jumper between E16+E17, and change the fuse to .125 amps.

beginning installation! The SIXMIX console is a professional product,

the Caller’s audio, to prevent feedback and echo.

be fed to either Channel 3 or Channel 2.

HENRY ENGINEERING

503 Key Vista Drive

Sierra Madre, CA 91024

Tel: [phone]

www.henryeng.com

the two jumpers between

PAGE 2

2.2 CONNECTIONS AND WIRING

All connections are on the back panel. XLR connectors are used for mics; ¼” TRS (Tip-Ring-Sleeve) jacks are used
for most other I/O. ALWAYS use TRS (“stereo”) plugs for ALL ¼” jacks. Unbalanced inputs are via standard RCA
jacks. Note that the upper jacks are RIGHT channels; the lower jacks are LEFT channels.

2.2.1 MIC INPUTS

The SIXMIX has inputs for 2 microphones. Microphones should be low-impedance professional units with
balanced outputs. Dynamic or ribbon mics are suggested. Powered condenser mics can be used, although the
console does not provide phantom power. Connect microphones to the female XLR connectors on the rear of the
console. The mic plug should be wired as follows:
PIN 1: Ground
PIN 2: High
PIN 3: Low

2.2.2 MIC PROCESS INSERT

The SIXMIX provides for the insertion of external microphone processing equipment, e.g., a mic limiter or equalizer.
External mic processing equipment should be interfaced via the TRS Mic Process Insert jacks. These jacks insert
the processing gear just after the console’s mic preamps, but before the mic channel faders. The mic preamp
output and return circuits are unbalanced, at a nominal level of –10 dbu.
Wire the mating TRS plug as follows:
TIP: To processor input (from mic preamp output)
RING: From processor output (to console fader input)
SLEEVE: Ground.

2.2.3 LINE INPUTS

Line level inputs are used for CD players, tape decks, and other analog sources that operate at line level.
SIXMIX has 4 stereo Line mixing channels, each of which has two inputs: “A” and “B”. The A inputs are for
professional balanced source equipment; the B inputs are for “consumer” unbalanced source equipment. Input 6A
is dedicated to the internal USB codec for use with a computer, hence there is no 6A input jack.

Connect balanced

source equipment via the TRS input jacks labeled 3A, 4A, and 5A. The upper jack is for the
RIGHT channel; the lower jack is for the LEFT channel. Wire the TRS plug as follows:
TIP: High
RING: Low
SLEEVE: Ground (For most installations, connect the ground wire at both ends

.)

Connect unbalanced

(consumer) source equipment to the RCA jacks labeled 3B, 4B, 5B, and 6B. The upper (red)

jack is the RIGHT channel; the lower (white) jack is the LEFT channel.

2.2.4 USING A TELEPHONE HYBRID

If the console will be interfaced to a telephone hybrid (for broadcasting telephone calls), the Receive (Caller) output
of the hybrid should be fed into Channel 3A or 3B. This is because the Mix Minus output of the console contains
ALL line sources mixed to the Program bus, except for Channel 3. This “Program-minus-caller” Mix Minus output is
fed back to the hybrid’s Send input. The caller will therefore be able to hear all sources mixed on the Program bus,
minus himself. Note: The hybrid can also be used on Channel 2, if that channel is not being used for a
microphone. See Section 2.1.2 of this manual.

2.2.5 AIR MONITOR INPUT

The SIXMIX console provides an Air Monitor input that can be used to feed an off-air monitor into the console’s
Monitor system. This input is electrically identical to the other balanced Line channel inputs, and should be
connected the same way. Any professional demodulator or tuner can be used.

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2.2.6 PROGRAM OUTPUT

The SIXMIX console’s main stereo mix bus output is the Program output. This output is electronically balanced and
will drive a 600 ohm load. The nominal level is +4dBm. Wire the TRS plug as follows:
TIP: High
RING: Low
SLEEVE: Ground
Note: To feed an unbalanced load, connect to the TIP and SLEEVE only.

DO NOT SHORT THE RING TO

GROUND! An unbalanced Program output is also available via the REC OUT jack. See Section 2.2.11.

2.2.7 MIX-MINUS OUTPUT

The Mix-Minus output is unbalanced at 0 dBu and will drive a 600 ohm load. The output is a mono mix of the
Program bus, minus the channel to which the hybrid is connected (Chan. 2 or Chan. 3 – see Section 2.1.2). Wire
the plug as follows:
TIP: Mix-Minus output
RING: (Used for Cue output: see Section 2.2.8.)
SLEEVE: Ground

Warning: Do NOT use a two-circuit “mono” ¼” plug! Use a three-circuit “stereo” TRS plug only.

2.2.8 CUE OUTPUT

The output of the Cue bus appears on the RING terminal of the MIX-MINUS output jack. This output is affected by
the Cue Level volume control. It can be used for an external amplified cue speaker, or as a secondary (mono) utility
output. The output is unbalanced, at about -10 dBv nominal level. Connect to the RING of the Mix-Minus TRS plug.

2.2.9 MONITOR OUTPUT

The console’s Monitor outputs are for driving the studio monitor speaker power amplifier. These outputs are
unbalanced, and will drive 600 ohm loads. The nominal level is –10dBm. Connect the mating TRS plug as follows:
TIP: Left Monitor output
RING: Right Monitor output
SLEEVE Ground

2.2.10 ANNOUNCE BOOTH “GUEST POD” HEADPHONE OUTPUT

The SIXMIX console provides a secondary headphone output for use by a booth (or guest) announcer. This
GUEST POD output can be connected to a Henry Engineering MultiPhones Guest Pod headphone module. Use
cat5 cabling to connect from the RJ45 connector on the SIXMIX to the mating connector on the Guest Pod.

Warning: Do NOT use “Crossover” cat5 cables! See Section 4.4.2 for note re: Guest Pod installation.

2.2.11 RECORD OUTPUT

The Record Output, an 1/8” TRS mini-jack, is identical to the Program output, except that it is for use with
unbalanced equipment, e.g., feeding the line input of a cassette recorder or computer sound card. The output level
is -10 dBu. Wire the TRS mini-plus as follows:
TIP: Left channel output
RING: Right channel output
SLEEVE: Ground

2.2.12 USB CONNECTION

The SIXMIX console includes a built-in USB professional audio codec (A/D and D/A) which allows digital audio
recording and playback on any computer that supports a USB audio device (USB 1.1 or higher). Connect an
appropriate cable from the USB jack on the console to the USB connector on the computer.

2.2.13 SPDIF OUTPUT

The SIXMIX provides a SPDIF digital output directly from the computer. Note that this output is not the output of
the console; it provides a digital output of the PCs play audio only. Nothing else is mixed in.