Hear technologies Hear back User manual

user guide

Part No. LIT002420UG

c2002, Hear Technologies

12-2002

TALK BACK 600

TALK BACK 200

OTHER HEAR TECHNOLOGIES PRODUCTS

RC-1 RC-2

wired remotes

(optional for models 200 & 600)

wireless remotes

(optional for model 600 only)

RF-1 RF-2

TALK BACK

The Talk Back models 200 and 600, add talk back

capability and control room monitor dimming to recording

consoles, digital audio workstations, and portable audio

workstations. Optional wired and wireless remotes (single

and dual-button versions) are available for control of the

talk back and/or monitor select functions. In addition to

these features, the model 600 has control room monitor

switching and optional wireless RF remote control.

The Talk Back permits the engineer to control talk back

and monitor switching from: the front panel switches, the

wired remotes, and the RF wireless remotes (600 only).

Applications include professional recording studios,

project studios, and video post-production facilities. The

unit's features and audio specifications rival or surpass

those found in large format recording consoles.

Quantum Technologies, Inc. (QTI) warrants the equipment against defects in materials and labor for a period of one year from the original date of purchase.The duration of this warranty

is limited to claims made to QTI within the periods stated with respect to parts and labor from the date of purchase. During the warranty period, defective equipment will be replaced or

repaired to the general condition as received, at the discretion of QTI.

All transportation is the responsibility of the purchaser or owner. Equipment should be shipped in the original shipping box.

This warranty applies only to defects in materials and workmanship and does not cover failure or damage due to shipping loss or damage, abuse, misuse, misapplication, incorrect or

varying power line voltages, lack of proper maintenance, natural disasters, acts of God, or unauthorized modifications, repairs, or any alterations done without the expressed written

consent by QTI. QTI shall not be liable for any loss of use of the equipment, or consequential damages, including damages to other parts of the installation in which the equipment is a

part.

QTI does not make any warranty, express or implied, other than the warranty contained herein. No agent, representative, or employee has the authority to increase or alter the liability,

obligations, and terms of this warranty or sale of the equipment. NOTE: It is strongly recommended that any equipment returned to QTI be properly packaged and insured for its full

value in case of loss, handling or shipping damage.

QTI shall not be responsible for damage or loss of equipment during shipment. The following are registered trademarks of Hear Technologies: Hear

Technologies, Hear Back, Talk Back, Extreme Extender, Hearbuds, HearBus,

and the "Jack" logo. All names and marks of other companies belong to

those respective companies.

LIMITED WARRANTY

03 system description

04 hear back hub

04 hub features

04 hub inputs

04 input selector switch

04 hub outputs

04 mixer RJ45 pinouts

04 input metering

04 internal fan

04 front and rear panel detail

05 hear back mixer

05 mixer features

05 mixer construction

05 status indicators

05 link operation

05 limiter

05 front panel detail

06 line outputs

06 aux in

06 master volume

06 headphone amplifier

06 connecting and calibration

07 system block diagram

08 system specifications

09 troubleshooting and operating tips

10 hook-up diagrams

10 two studios

12 church - analog

13 digital audio workstation

14 recording studio

15 large stereo system - analog

16 stereo live - analog

17 stereo live - digital

18 hear back system accessories

18 extreme extender adat in/out

18 hearbuds & hearbud headset monitor

18 cables

19 other hear technologies products

19 limited warranty

CONTENTS

HEARBUDS &

HEARBUD HEADSET

MONITOR

HearbudsTM provide an

affordable in-ear monitor

headset that delivers

professional performance

at a great value. By

creating acoustic chambers at the ear, hearbuds not only

dramatically improve the sound of standard in-ear

headphones and ear-pieces, their molded, 100% silicon,

design also significantly reduces unwanted background

noise levels - enabling you to enjoy sound clarity at lower

volumes. Included in each package are three sizes for a

perfect fit. And, because they're audiologically designed,

they're comfortable to wear and won't fall out of your

ears, either!

Features:

•Better sound quality at lower volumes

•Can be used on stage and in the studio

•Great for Hear Back, MP3 players, cell-phones, and

other personal audio

•Hearbuds alone fit most in-ear headsets

•Works great in noisy environments because they

block unwanted sounds

•Comfortable, safe, and secure

•Designed by audiologists

•Washable

HEAR BACK SYSTEM ACCESSORIES

EXTREME EXTENDER ADAT IN/OUT

ADAT Extreme ExtendersTM IN/OUT are available for

converting from ADAT optical to HearBus and vice versa.

Extender Features:

•Extend ADAT® Optical cables up to 500 feet

•Convert HearBus to ADAT® Optical or vice versa

•Uses standard CAT5E cables

•Does not affect sound quality

•Small size, durable construction

•Clock Status LED on Extreme Extender OUT

The units were designed to solve ADAT optical distance

limitations. The extreme extender ADAT IN converts ADAT

optical to HearBus.

Using CAT5E the effective length of an ADAT optical

interface can be extended up to 500 feet. This is

accomplished without any loss of audio quality. The ADAT

"Thru" output provides a buffered pass-thru for connection

to local ADAT devices.

The Extreme Extender ADAT OUT converts the CAT5E

HearBus to ADAT optical. Two parallel optical outputs on

the Extender ADAT OUT provide drive for two separate

ADAT devices. A bi-color clock status LED indicates the

presence (green) or absence (red) of the ADAT clock.

In addition to acting as an ADAT optical extender, the

Extreme Extender ADAT IN may be connected to the

optical output of any ADAT device, such as a DAW, mixer,

etc. and connected to the input of a Hear Back hub.

The extreme extender ADAT OUT can be connected to the

HearBus out of a hub to obtain two ADAT outputs.

CABLES - Quality cables that work with your Hear Back

System.

ADAT OUT

ADAT IN ADAT OUT

ADAT THRU

HearBus Out HearBus IN

9VDC

CLK

PWR

CAT5E cables are

available in 2, 12,

25, 50, and 100

foot lengths.

Optical cables

are available in 6,

12, and 25 foot

lengths.

EXTREME EXTENDER

ADAT IN

Connections:

EXTREME EXTENDER

ADAT OUT

ADAT® is a registered trademark of Alesis Corporation.

HEAR BACK SYSTEM DESCRIPTION

The basic Hear Back™ system consists of a hub

and personal mixers. The hub receives any of

the three input signals and converts them to

HearBus digital audio plus power. The mixers

are connected to the hub using CAT5E cable.

A single hub supplies digital audio and power to

a maximum of eight mixers. That's one for you

and everybody in the band! If that's not enough,

the hubs can be daisy-chained using the

HearBus In and HearBus Out for virtually

unlimited system size.

The hub may be connected to recording

equipment, digital audio workstations, and

analog or digital consoles.

The mixer is placed near the talent and gives

them control over the audio inputs. The user-

friendly system saves system setup time.

•Virtually unlimited system size

•Excellent quality and audio fidelity

•High power - low distortion

headphone amplifiers

•Very long interconnect without loss

of audio quality

•Three audio inputs: ADAT® optical,

analog, and HearBus are switch

selectable from the front panel

•Local control of up to ten channels

of audio - 8 inputs plus a stereo Aux

input

•Built-In DSP limiter for hearing and

monitoring device protection

•Headphone amplifier fault LED

•Bus status indicator

•Link indicators/switches - links mono

pairs for stereo operation

•Standard CAT5E cable for power

and signal connection to mixers

•Built-in cable strain relief

•Balanced line outputs - mono/stereo

•Stereo AUX in

•Built-In mic stand mount as well as

desktop mount capability

ADVANTAGES / FEATURES

Note: This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part 15 of the FCC Rules. These limits are

designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses and can radiate radio

frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is

no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which

can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures:

• Reorient or relocate the receiving antenna.

• Increase the separation between the equipment and receiver.

• Connect the equipment into an outlet on a circuit different from that

to which the receiver is connected.

• Consult the dealer or an experienced radio/TV technician for help.

FCC Statement

0318

HUB INPUTS

1. ADAT®

The ADAT input (5) can be connected to digital audio

workstations, digital recorders, or digital mixers using a

standard TOS-Link optical cable. For front of house or remotely

located digital mixers, use a Hear Technologies Extreme

Extender ADAT IN* that converts ADAT optical, which is limited

in distance, to the HearBus for transmission of up to 500 feet.

Use Hear Technologies Optical cables available in 6, 12, and

25 foot lengths.

*ADAT Extreme Extenders In/Out are available for converting from ADAT to

Optical to HearBus and from HearBus to ADAT Optical.

2. HearBus™

The HearBus permits daisy-chaining of multiple hubs up to

500 feet apart using the HearBus input (6) and HearBus

output (7). This HearBus is great for inter-studio or stage-to-

stage connections, as well as daisy-chaining for very large

systems. Use Hear Technologies CAT5E cables, which are

available in 2, 12, 25, 50 and 100 foot lengths.

3. Analog

Analog inputs (9) are fully balanced and are connected using a

standard TASCAM DA-88 style Analog cable, such as the Hear

Back Analog cable.

DB25 cable pin-outs are wired as shown below:

INPUT SELECTOR SWITCH - The input selector switch (2)

gives the user a simple way to select any one of the three input

sources without a patch bay, router or rewiring.

HUB OUTPUTS - The hub has mixer outputs (8) which each

deliver digital audio, ground and +/- 18VDC. Each of the eight

hub outputs must be home run to a mixer, with a maximum

distance of 200 feet. Outputs not in use should be disconnected

at the hub.

MIXER RJ45 PINOUTS

Pin Function Pin Function

1 Digital Audio + 5 -18VDC

2 Digital Audio - 6 Ground

3 Ground 7 +18VDC

4 +18VDC 8 -18VDC

Each of the eight hub mixer outputs has a solid-state

automatically resettable fuse in-line with the power supply

outputs to prevent power supply damage. In the event of a

shorted cable or broken mixer, the PTC fuses go to high

impedance permitting other mixers to function while protecting

the power supply from the faulty output.

The main AC input is connected using a standard IEC320 cable.

The universal power supply is designed to operate from 90 to

264VAC at 50 to 60Hz. The AC input circuit is internally fused.

A front panel power switch (3) is provided for convenience.

INPUT METERING - The hub features a unique input metering

circuit consisting of three LED's for each of the eight input, while

providing four visual levels. The middle blue LED's operate at

two different brightness levels. The green LED indicates -32 dBu

signal presence, the blue at -10 dBu (dim) and +4 dBu (bright)

and the red clip LED operate at +16 dBu.

INTERNAL FAN - The internal temperature-controlled fan

operates whenever the power supply temperature reaches 60oC

or 140oF. In studio or indoor use, the fan should rarely come on.

The hub should be rack mounted away from high temperature

devices such as power amplifiers.

RL LINK RL LINK RL LINK

RL STEREOMIXER RL LINK RL LINK RL LINK

RL STEREOMIXER

FRONT PANEL

5 6 7 8 9

2 4

Four-Level, 3-LED Input Metering

Input Selector Switch

HearBus Clock Status Indicator

AC Power Switch

AC Power Entry

ADAT Optical Input

HearBus Input

HearBus Output

Hear Back Mixer Outputs

Analog Inputs

HUB FEATURES

•Three switch selectable 8-channel input sources:

ADAT Optical, Analog, HearBus

•24-bit A/D converters

•Digital input sample rates: 44.1 KHz or 48 KHz

•Less than 1.5 milliseconds total system delay (latency)

•3-LED four-level metering

•Standard CAT5E - delivers power and signals to mixers

•Daisy-chain for very large systems

•Internal, internationally approved universal power supply

•Quiet, temperature controlled fan (only runs when power

supply temperature reaches 60oC or 140oF)

•1 RU chassis

CAUTION: Use only DA-88 Analog. Do not use TDIF.

REAR PANEL

WARNING:

NO USER SERVICEABLE

PARTS INSIDE

ADAT IN HearBus

NOT FOR MIXER

MIXER OUTPUTS ANALOG INPUTS

HearBus

OUT

NOT FOR MIXER MIXER OUTPUTS DA-88 ANALOG CABLE

FUSE: 1A @ 115VAC,

0.5A @ 230VAC

50 / 60 Hz

1704

HOOK-UP DIAGRAM STEREO LIVE - DIGITAL

HOOK-UP DIAGRAM STEREO LIVE - ANALOG MIXER FEATURES

MIXER CONSTRUCTION

The Hear Back mixer is constructed of UV-stabilized ABS

and has a built-in mic stand mount. Two cable strain reliefs

greatly reduce stress on the CAT5E cable connectors and the

mixer RJ45 connector.

STATUS INDICATORS

The mixer has three types of status indicators:

1. BUS - The bus indicator (1) is a bi-color LED that is green

under normal operating conditions, indicating the

HearBus clock is present. In the absence of the clock, the

indicator turns red alerting the user a problem exists at

the hub or connection to the hub.

2. LINK - The link indicators (2), (14) and (16) illuminate

whenever the associated link switch(es) (4), (6) and (8)

are pressed. Switch settings are stored in non-volatile

flash memory whenever power is removed.

3. HEADPHONE AMPLIFIER FAULT - The fault indicator (22) is

normal off and only illuminates red if an over-current or short

circuit condition occurs. The circuit shuts down the

headphone amplifier and upon cooling returns to normal

operation. Continued cycling of the fault circuit is not

recommended as excessive cycling can degrade the

amplifier's performance and life.

LINK OPERATION

Normally, a stereo mix is connected to the hub channels 1 and

2. These are typically the front of house or control room mix and

are controlled using the mixer stereo input knob (9).

The "more me" inputs are typically mono and are controlled

using the mono control knobs (3), (13), (5), (15), (7) and (17). The

mono signals are center-panned in the stereo field when the link

indicator is off.

When a pair of mono inputs are linked, three things occur;

1. The left channel becomes the link master volume control for

the stereo pair.

2. The two inputs are hard panned left and right. Inputs can be

adjusted at the source to have a stereo spread anywhere

desired. Stereo signals are realized by using a pair of the

mono inputs: 2/4, 5/6, and/or 7/8 by simply pushing the link

switch (4), (6), or (8).

3. The right mono volume now becomes inactive.

LIMITER

The limiter gives the user ultimate control of his/her hearing

protection as well as headphones, in-ear and conventional

loudspeaker monitoring devices in the event of excessive input

levels. The two-stage DSP limiter is an :1 or "brick wall"

limiter. The limiter is controlled using simple threshold

adjustment (19).

The limiter active blue LED (18) illuminates when the limiter is

active. If the indicator operates during normal program material

the dynamic range and quality of sound will suffer. NOTE:

Limiter should only be active when excessive signals are

present. To set the limiter, see Hear Back Connecting and

Calibration on page 6.

•Local control of up to ten channels of audio

•Master volume

•Built-in DSP limiter

•24-bit D/A converters

•Less than 1.5 millisecond total system delay

•Bus status indicator

•Headphone amplifier fault indicator

•Link indicators

•Standard CAT5E power and signal connection

•Balanced, mono/stereo, line outputs

•+4 dBu level TRS unbalanced stereo AUX in:

- Expand numbers of mixes

- Drum module/metronome or local mix input

Bi-Color Bus Status Indicator

Link Indicator - Channels 3/4

Mono Channel 3/Stereo Link Master

Level

Link Switch - Links Channels 3/4

Mono Channel 5/Stereo Link Master

Link Switch - Links Channels 5/6

Mono Channel 7/Stereo Link Master

Link Switch - Links Channels 7/8

Stereo Mix Level Control, Channels 1/2

Stereo Auxiliary Input

Right Line Output

Left/Mono Line Output

Mono Channel 4

Link Indicator - Channels 5/6

Mono Channel 6

Link Indicator - Channels 7/8

Mono Channel 8

Limiter Indicator

Limiter Threshold Control

Master Volume

Headphone Output

Headphone Amplifier Fault Indicator

Headphone Output

4 6 8

3 5 713 15 17

14 16

4 86

0516

HOOK-UP DIAGRAM LARGE STEREO SYSTEM - ANALOG

NOTE: Each hub gets the stereo mix and sectionals.

Each master hub can have 31 hubs daisy-chained from it.

LINE OUTPUTS

Two balanced ¼ inch Tip, Ring, and Sleeve line outputs are

provided - (11) and (12). The left operates as a mono output for

sub woofers and mono devices if nothing is plugged into the

right line output. When a ¼ inch plug is inserted into the right

output the line outputs operate in normal stereo mode. The

line outputs may be used simultaneously with the headphone

outputs and are both controlled with the master volume knob

(20). In the event of ground loops when connecting the mixer

line outputs to other devices that have an earth ground, it may

become necessary to lift the shield at the mixer outputs.

NEVER lift or disconnect the AC safety ground of any device.

AUX IN

The auxiliary input (10) is a 1/8 inch Tip, Ring, and Sleeve input

optimized for +4 dBu input levels. These signals are summed

into the analog section of the mixer just upstream of the

master volume (20). The input permits another stereo mix to be

inserted into the mixer. Examples of use would be a drum

machine click track into the drummers mixer. Another

application would be a stereo mix from a guitar or keyboard

local mix, another Hear Back Mixer, creating a total of ten

channels controlled from your mixer.

MASTER VOLUME

The master volume (20) is used to set the volume of the

headphones and the line outputs. When using the line outputs

in conjunction with the headphones, optimize the mix for the

headphones and then adjust the device connected to the line

outputs to balance the gain. Follow the same procedure if

using the AUX input; once the desired mix is obtained, adjust

the source to get the desired level at the AUX input.

HEADPHONE AMPLIFIER

The headphone amplifier outputs (21) and (23) are paralleled

outputs. When using multiple headsets, the total impedance

should not go below 16 ohms. The headphone amplifiers are

very powerful and can easily damage in-ear transducers,

headphones, and your hearing; exercise great care in

adjusting the master volume. At 50 ohms the amplifier is

capable of sustaining 2 watts of power! The amplifiers are

short circuit protected and have a fault indicator (22).

HEAR BACK CONNECTING AND CALIBRATION

1. Connect the appropriate input(s), as shown in the hook-up

diagrams beginning on page 10, and select the desired

input using the front panel switch. Connect mixers to the

hub outputs using CAT5E cables and set all mixer controls

to off (full counter-clock-wise position, except the limiter

which should be fully clock-wise), connect the headphones,

in-ear monitors, and/or line outputs for connecting to

wireless in-ear systems, powered monitors, or other

devices requiring line-level inputs.

2. Turn on hub power.

3. Adjust the level at the input source (DAW, Mixer, etc.) until

the clip LED's on the hub just come on and then reduce the

input(s) until you have a bright blue LED. NOTE: Adjust the

source for as much signal into the hub as possible without

clipping. Higher input levels improve signal-to-noise and

dynamic range.

4. Mixer Adjustment: Once you have the signals optimized,

turn the master volume to about 10 o'clock and then raise

the stereo mix to a comfortable level normally around 10

o'clock. Adjust the "more me" mono/stereo inputs 3-8 to the

desired levels. Avoid adjusting the Master Volume too high

and running the inputs too low.

5. Limiter Adjustment: Once a mix is established, turn the

limiter threshold knob counter-clockwise until the blue LED

just comes on, then turn clockwise until the LED goes off.

This sets the limiter to protect your hearing and monitoring

device in the event an input goes above normal levels. The

limiter should only come on when this condition occurs.

Causing the limiter to operate (blue LED on) during normal

operation will cause a loss of dynamic range and will add

distortion to the signals being monitored. Remember, it is

for excessive signals only.

NOTE: The HearBus and mixer outputs contain high speed

digital audio and should be treated as a transmission line. Do

not "Y" these connections because the terminated controlled

impedance will be comprised. The HearBus and mixer outputs

operate at 12.28 MHz.

Now enjoy personal monitoring at its best and have fun!

11 12

21 23

!WARNING

The Hear Back Mixer is capable of driving most

headphones to extreme levels that can damage your

HEARING!

ALWAYS turn down the mixer "Master Volume" down

before putting on in-ear headsets or headphones.

The mixer Limiter is pre-master volume and protects

from excessive input signals. It is the user's

responsibility to prevent hearing damage by virtue of

excessive headphone "Master Volume" settings.

1506

SYSTEM BLOCK DIAGRAM

uCONTROLLER

HearBus

MONO/LEFT

LINE OUT

24 BIT D/A

CONVERTER

RCVR

DSP

24 BIT D/A

CONVERTER

RIGHT LINE

OUT

MONO 3 - L

MONO 4 - R

LINK 3 - 4

LINK 5 - 6

MONO 6 - R

MONO 5 - L

LINK 7 - 8

MONO 8 - R

MONO 7 - L

LIMITER

THRESHOLD

LINK 3 - 4

LINK 5 - 6

LINK 7 - 8

LIMIT

STEREO

MASTER VOLUME

HP FAULT

BUS

HEADPHONE

OUT 2

HEADPHONE

OUT 1

STEREO

AUX IN

+ 16dB

CLIP

-32

-10 .. +4

ADAT OPTICAL

-18VDC

+18VDC

+5VDC

UNIVERSAL

POWER SUPPLY

24 BIT A/D

CONVERTER

HearBus

ANALOG

DIGITAL CIRCUITRY

INPUT

SELECT

CLOCK

EIGHT MIXER OUTPUTS

MIXER OUTPUTS

HearBus

Input Merering (x8)

SHORT CIRCUIT PROTECTION

HEAR BACK MIXER

HEAR BACK HUB

PATENT

PENDING

MIXER INPUT

AC POWER IN

ADAT IN

ANALOG INPUTS

HearBus IN

HearBus OUT

LINK MASTER/

HOOK-UP DIAGRAM RECORDING STUDIO

0714

1308

SYSTEM SPECIFICATIONS

Note: 0 dBu = 0.775 V rms

*Specifications and features subject to change without notice.

Aux Input

Input Configuration/Impedance: Stereo, unbalanced, 10 Kohms typical

Input Level: +4 dBu optimal, +22 dBu max

Head Phone Power

Load Impedance: THD less than 0.01%* THD less than 0.1%

8 Ohms: 150 mW* 230 mW

*THD AT 8 Ohms = 0.015% typical

16 Ohms: 235 mW 500 mW

25 Ohms: 675 mW 775 mW

32 Ohms: 950 mW 1.1 W

50 Ohms: 1.6 W 1.8 W

100 Ohms: 1.14 W 1.25 W

200 Ohms: 500 mW 650 mW

600 Ohms: 215 mW 220 mW

Inter Modulation Distortion: Typically less than 0.03%

Line Out

Freq Response: 20 Hz to 20 KHz, +0.04 dB, -0.55 dB

THD+N: 0.008% typical at 1 KHz, +15 dBu,

0.02% typical, 20 Hz – 20 KHz, +4 dBu

Inter Modulation Distortion: 0.02% typical at +4 dBu, 60 Hz/7 KHz

Crosstalk: Better than -85 dB @ 1 KHz

Propagation Delay: Less than 1.5 mSec

Noise Performance

Noise, A-Weighted: -91 dBu analog, -97 dBu optical

Dynamic Range: 112 dB typical

System I/O

Hub Line In, Analog: 8 Balanced inputs on DB-25 female (Tascam DA-88 pinout)

Maximum Input Level, Analog: +15 dBu

Hub Light Pipe In: Industry standard fiber optic connector, shuttered

Hub HearBus In, Out: 8-pin RJ45 jack (2 each)

Mixer Headphone Out: TRS 1/4" unbalanced stereo (2 each)

Mixer LIne Out: TRS 1/4" balanced (2 each)

Maximum Output Level, Analog: +24 dBu (mixed output)

Aux Input: TRS 1/8" unbalanced stereo

Physical, Mixer

Size: 11.5" (29.2 cm) H x 5.2" (13.2 cm) W x 3.6" (9.15 cm) D

Unit Weight: 1.2 lb. (0.54 kg)

Mounting: Standard mic stand or desk mounted

Physical, Hub

Size: 1.75" H x 19" W x 7.125" D

Unit Weight: 5.0 lb.

Mounting: Standard rack mount, 1 RU

Power

Requirements: 100-230VAC, 50/60HZ, 100 Watts

HOOK-UP DIAGRAM DIGITAL AUDIO WORKSTATION

No Signal  Verify power is on.

 Check input connections and input selector switch.

 Verify the hub and mixers have green clock status indications.

 Check output devices, headphones, wireless transmitter/receiver, monitor amplifiers, etc.

When I connect a line level

device to the mixer line

outputs, I hear a buzz.

 Wire TRS outputs using only black (ring - ) and red (tip +) wires.

 Disconnect shield at the mixer and terminate at receiving end only.

 For unbalanced outputs wire the Black (ring - ) to the receiving end sleeve and tie the shield at the

receiving end only. Connect the tip (+ red) to the tip at the receiving end.

Setting the limiter  Set the limiter so it only activates in the presence of an excessive input signal. The limiter should only

be active in the event of excessive signals and should NOT be on when normal signals are present.

I have a clock signal at the

hub, but nothing at the mixer.

 Isolate the problem as follows:

 Check CAT5E cable or try another cable.

 Try another mixer output port on the hub.

 Try another mixer.

When I link two mono channels,

the stereo spread is incorrect.

 Verify the source (mixer, DAW, etc.) has these outputs panned hard left and right. The pan control of

the source determines the stereo spread.

The headphone amplifier fault

indicator is on.

 The fault indicator indicates either a short circuit or excessive load.

I need more mixes.  Connect the stereo mix (channels 1&2) with the FOH or control room mix across several hubs (as

many as desired) then provide the "more me" sectional mixes to channel 3-8 on each hub until the

desired number of mix's are met. See "Large Stereo System" hook-up diagram, page 15.

NOTE: The HearBus and mixer outputs contain high speed digital audio and should be treated as a transmission line.

DO NOT "Y" these connections because the terminated controlled impedance will be comprised.

The HearBus and mixer outputs operate at 12.28 MHz.

If you need further assistance, feel free to contact Hear Technologies technical support at 1-256-922-1200.

TROUBLESHOOTING AND OPERATING TIPS

The fan does not operate.

How to parallel channels 1 & 2

(stereo inputs) across multiple

"Master Hubs" as shown in

the "Large Stereo System"

hook-up diagram on page 15

 The fan only runs when power supply temperature reaches 60oC or 140oF.

 After connecting the stereo mix to channels 1 and 2 at each hub - Connect master hub #1, channels 3-

8 for band mix, connect master hub #2, channels 9-14 for vocals section, connect master hub #3,

channels 15-20 for horns ... you get the idea, right! By using the HearBus outputs on the master hubs

and connecting them to the slave hub HearBus inputs, you can obtain as many mixing stations of each

master mix as desired. Since each hub may be daisy chained a minimum of 32 times, this example

system yields 3 master hubs x 32 slave hubs = 96 hubs, then 96 x 8 = 768 mixers!

NOTE: When "Y" connecting multiple hub inputs, one must be concerned with the total impedances.

The hub inputs are 18K ohms balanced. Since the input to output impedance ratio should be at or

above 10:1, there are a couple of rules to follow: Assuming a mixer source impedance of 180 ohms,

the following applies: 18000/1800 = 10.

Where: 18000 = source impedance

1800 equals ten times your source impedance

10 = 18000/1800 is the number of hubs that meet the required impedance

Therefore, you can parallel up to ten master hubs to a quality BALANCED line output. In the event you

experience problems or if you have an unbalanced output, obtain a high quality, balanced audio

distribution system. We don't recommend using unbalanced sources for this connection scheme as

hum loops will occur.

HOOK-UP DIAGRAM CHURCH - ANALOG

0912

HOOK-UP DIAGRAM STUDIO A HOOK-UP DIAGRAM STUDIO B

1110

HOOK-UP DIAGRAM STUDIO A HOOK-UP DIAGRAM STUDIO B

1110