SM Pro Audio SM DI4 Value User manual

SMProAudio
Operating Manual
SM DI4Value

SAFETY INSTRUCTIONS
CAUTION: To reduce the risk of electrical shock, do not remove the cover or rear panel of this
unit. No user serviceable parts inside. Please refer servicing to qualified personnel only.
WARNING: To reduce the risk of fire or electrical shock do not expose this appliance to rain or
moisture.
DETAILED SAFETY INSTRUCTIONS:
All safety and operation instructions of this manual should be read and adhered to before
operation.
Retain Instructions:
Please retain all safety and operating instructions for future reference.
Follow instructions:
All operation and user instructions should be followed.
Water, liquid and Moisture:
The appliance should not be used near water, rain or other liquids. Make sure that no liquid can
leak, spill or otherwise seep into the appliance.
Ventilation:
Please place the appliance so no obstacles interfere or impede the flow of air through the
ventilation openings.
Heat:
The appliance should be situated away from other heat sources such as heaters, radiators,
ovens, or other appliances that produce heat.
Power Source:
Make sure your appliance is set to the correct voltage for the country in which it will be used.
Grounding and Polarization:
Precautions should be taken so that the grounding or polarization means of an appliance is not
defeated.
Power-Cord Protection:
Power supply cords should be routed so that they are not likely to be walked on, pinched, dam-
aged, worn, or rubbed by any other device or obstacle.
Cleaning:
The appliance should be cleaned only with a light soft cloth. Do not use any damaging or
corrosive products on the unit.
Periods of inactivity:
The power cord of the appliance should be unplugged from the outlet when left unused for a long
period of time.
Damage Requiring Service:
The appliance should be serviced by qualified service personnel when:
- The power supply cord or the plug has been damaged; or
- Objects have fallen, or liquid has been spilled into the appliance; or
- The appliance has been exposed to rain; or
- The appliance does not appear to operate normally or exhibits a marked change in
performance; or
- The appliance has been dropped, or the enclosure damaged.
Servicing:
The user should not attempt to service the appliance beyond that is described in the Operating
Instructions.
All other servicing should be referred to qualified service personnel.

SM DI4 Main Features
Professional, multi-purpose DI (direct injection) Box/Line mixer for stage and studio applications
- Four totally independent DI Box units in 1/2 RU package
- Independent 20dB PAD switch per channel
- Independent earth(Ground) lift switch per channel
- Independent rotary volume control per channel for line mixer output
- Independent rotary pan control per channel for line mixer output
- Master Volume
- Headphone output
- Stereo line output
- High-quality components and rugged construction
FOREWORD
Dear Customer,
Thank you very much for expressing your confidence in SM ProAudio products by purchasing
this unit. The SM DI4 has been designed to be used as a standard tool for home/pro studios, P.A.
rental companies etc. With much experience in the audio industry over a long period of time, and
along with valuable suggestions from our customers, our engineers have developed a product we
know you will be satisfied with. We guarantee you uncompromising quality (manufactured under
ISO9000 certified management system) as well as excellent technical and audio properties at an
extremely affordable price.
Regards,
SM ProAudio

TABLE OF CONTENTS
1. INTRODUCTION
2. THE DESIGN CONCEPT
2.1 High quality components and design
2.2 Inputs and outputs
3. INSTALLATION
3.1 Rack mounting
3.2 Mains voltage
3.3 Audio connections
4. FRONT PANEL CONTROLS
4.1 Independent (4 x) rotary volume controls for each channel to line mixer stereo output
4.2 Independent (4 x) rotary pan controls for each channel to line mixer stereo output
4.3 Independent (4 x) 20 dB PAD switch
4.4 Independent (4 x) earth(Ground) lift switch
5. APPLICATION
5.1 Using the SM DI4 as a DI Box
5.2 Using the SM DI4 as a line mixer
6. SPECIFICATIONS
7. WARRANTY

1. INTRODUCTION
In purchasing the new SM DI4, you have acquired a multi-channel DI Box/line mixer of high class
that meets all the demands and requirements of studio and live work. Due to its extensive
functions the SM DI4 is an extremely efficient and universal piece of equipment. The unit features
high quality multi-channel unbalanced to balanced line conversion, in addition to providing an
extremely useful built in line mixer all in a single unit rack-mount chassis. The SM DI4 finds
widespread application throughout the world, in home/pro studios, sound reinforcement systems
and in many other audio fields.
The SM DI4 features 4 independent DI Boxes!! That's right! 4 independent DI (direct injection)
unbalanced to balanced line converters. This is fantastic news for many uses in the studio or on
the road in live PA applications.
In addition, the SM DI4 also functions as multi-channel stereo line mixer. This is an ingenious
feature which will many musicians will find incredibly useful in live situations. Just think! You can
plug all your keyboards, samplers & modules into just one rack unit on stage and supply
independent XLR balanced outputs to the stage box for the front of house engineer.. AND set
your own independent mix for stage monitoring..cool! In Addition you have your own Headphone
output on the unit.
2. THE DESIGN CONCEPT
2.1 High quality components and design
The philosophy behind SM ProAudio products guarantees a no-compromise circuit design and
employs the best choice of components.
2.2 Inputs and outputs
All inputs and outputs are secured firmly to the exterior chassis housing. This ensures robust
quality and confidence in performance under all conditions.

3. INSTALLATION
Your SM ProAudio SM DI4 was carefully packed in the factory and the packaging was designed
to protect the unit from rough handling. Nevertheless, we recommend that you carefully examine
the packaging and its contents for any signs of physical damage, which may have occurred in
transit.
+ If the unit is damaged, please do not return it to us, but notify your dealer and the shipping
company immediately, otherwise claims for damage or replacement may not be granted.
Shipping claims must be made by the consignee.
3.1 Rack Mounting
The SM ProAudio SM DI4 fits into HALF a standard 19" rack unit of space (1 3/4"). Be sure that
there is enough air space around the unit for cooling. As to avoid overheating, please do not
place the SM DI4 on high temperature devices such as power amplifiers.
3.2 Mains voltage
The SM DI4 comes with a 16V AC power supply adaptor. Before you connect your SM DI4 to the
mains, please make sure that your local voltage matches the voltage required by the unit!
3.3 Audio connections
Analog inputs - On the front panel of the SM DI4 there are 4 1/4 inch unbalanced audio input jack
connectors (one per channel).
XLR balanced outputs - On the rear of the SM DI4 there are 4 x XLR balanced output
connections (one per channel).

4. CONTROLS
SM DI4 front panel
The SM DI4 has 4 independent direct injection unbalanced to balanced line converters in addition
to a built in 4 channel line mixer. The unit provides 2 rotary controls (Volume & Pan) and 2
switches per channel (Earth lift & 20dB PAD).
4.1 Independent (4 x) rotary volume controls for each channel to line mixer stereo output
Use these variable controls to set the level of each channel signal level sent to the stereo master
output section
4.2 Independent (4 x) rotary pan controls for each channel to line mixer stereo output
Use these variable controls to set the pan of each channel signal level sent to the stereo master
output section
4.3 Independent (4 x) 20 dB PAD switch
Use these switches to PAD each input channel signal level by 20dB. Use this only if you have an
extremely high input signal strength.
4.4 Independent (4 x) earth lift switch
Use these switches to lift the earth in the input signal of the current channel.

5. APPLICATION
5.1 Using the SM DI4 as a DI Box (direct injection unit)
Connect the signal you would like to convert from unbalanced to balanced to the SM DI4 via a
1/4 inch unbalanced jack to one of the channel inputs on the front panel of the unit. Connect an
XLR balanced cable to the corresponding channel output on the rear of the SM DI8 and connect
to your chosen destination.
If the input signal strength is too "hot" (high) you can depress the 20dB PAD switch to adjust to a
more appropriate level.
If there is an earth loop hum you can remove by depressing the earth lift switch. For Extra
grounding in a studio we have included a Ground Screw on the back of the unit.
5.2 Using the SM DI4 as a line mixer
You can mix volume & pan of all input signals to a single stereo pair of RCA connections on the
rear of the SM DI4. This enables use of the unit as a fully functional line mixer. This can be very
handy for many applications both live and in the studio.
Just connect the RCA stereo master outputs on the rear to your chosen destination (eg. Monitor
amplifier) and adjust the individual volume and pan controls for each individual channel on the
front of the SM DI4 to suit your needs.
A master volume control is provided on the front panel in addition to the individual controls.
Adjust this as necessary.
A Headphone output is also provided on the fron of the unit

6. SPECIFICATIONS
AUDIO INPUTS
Connectors 1/4" jack
Type TRS balanced
Impedance 47k Ohms
Min Sensitivity -20dB
Peak input level +16dB
STEREO LINE MIXER OUTPUTS
Connectors RCA Phono
Impedance 600Ohms
Max. output level +2dB (peak level +18.5 dB)
XLR BALANCED OUTPUTS
Connectors XLR
Type balanced
Min. output impedance 600Ohms
Max. output level 0dB (peak level +18.5dB)
DIST, FREQ, S/N RATIO & CROSSTALK
Frequency response 20Hz~20kHz, 0dB~-2B
Distortion 0.02%
S/N Ratio better than 74dB
Crosstalk rejection >80dB@1kHz;-20dB input
FUNCTION CONTROLS
Volume per channel variable
Pan per channel variable
POWER SUPPLY
Mains voltages USA/Canada ~ 120 V AC, 60 Hz
U.K./Australia ~ 240 V AC, 50 Hz
Europe ~ 230 V AC, 50 Hz
General export model ~ 100-120 V AC, ~ 200-240 V AC, 50-60 Hz
Power consumption 5.5VA
Fuse 100-120 V AC: 630 mA (slow-blow)
200-220 V AC: 315 mA (slow-blow)
Mains connection Through 16V AC Adaptor
PHYSICAL
Dimension 1 3/4" (44.5 mm) * 8" (230.6 mm) * 8 1/2" (217 mm)
Net weight approx. 1.75 kg
SM ProAudio is constantly striving to maintain the highest professional standards. As a result of
these efforts, modifications may be made from time to time to existing products without prior
notice. Specifications and appearance may differ from those listed or shown.

7. WARRANTY
1 WARRANTY CARD
To be protected by this warranty, the buyer must complete and return the enclosed warranty card
(signed/stamped by retail dealer) within 14 days of the date of purchase to SM ProAudio (see
address below 3). Failure to return the card in due time (date as per postmark) will void any
extended warranty claims.
2 WARRANTY
1. SM ProAudio warrants the mechanical and electronic components of this product to be free of
defects in material and workmanship for a period of one (3) years from the original date of
purchase, in accordance with the warranty regulations described below. If any defects occur
within the specified warranty period that are not caused by normal wear or inappropriate use, SM
ProAudio shall, at its sole discretion, either repair or replace the product.
2. If the warranty claim proves to be justified, the product will be returned freight prepaid by SM
ProAudio within Australia. Outside of Australia, the product will be returned at the buyer's
expense.
3. Warranty claims other than those indicated above are expressly excluded.
3 RETURN AUTHORIZATION NUMBER
1. To obtain warranty service, the buyer must call SM ProAudio during normal business hours
BEFORE returning the product (Tel.: [phone]). All inquiries must be accompanied by a
description of the problem. SM ProAudio will then issue a return authorization number.
2. The product must be returned in its original shipping carton, together with the return
authorization number, to the following address:
SM Pro Audio
Service Department
720 Glenhuntly Rd
Caulfield South
Melbourne, Victoria
Australia 3162

4 WARRANTY REGULATIONS
1. Warranty services will be furnished only if the product is accompanied by an original retail
dealer's invoice. Any product deemed eligible for repair or replacement by SM ProAudio under
the terms of this warranty will be repaired or replaced within 30 days of receipt of the product at
SM ProAudio.
2. If the product needs to be modified or adapted in order to comply with applicable technical or
safety standards on a national or local level, in any country which is not the country for which the
product was originally developed and manufactured, this modification/adaptation shall not be
considered a defect in materials or workmanship.
The warranty does not cover any such modification/adaptation, irrespective of whether it was
carried out properly or not. Under the terms of this warranty, SM ProAudio shall not be held
responsible for any cost resulting from such a modification/adaptation.
3. Free inspections, maintenance/repair work and replacement of parts are expressly excluded
from this warranty, in particular if caused by inappropriate use. Likewise, the warranty does not
cover defects of expendable parts caused by normal wear of the product. Expendable parts are
typically pots, potentiometers, switches and similar components.
4. Damages/defects caused by the following conditions are not covered by this warranty:
- Misuse, neglect or failure to operate the unit in compliance with the instructions given in the
user or service manuals.
- Connection or operation of the unit in any way that does not comply with the technical or safety
regulations applicable in the country where the product is used.
- Damages/defects that are caused by any other condition beyond the control of SM ProAudio.
5. Any repair carried out by unauthorized personnel will void the warranty.
6. Products which do not meet the terms of this warranty will be repaired exclusively at the
buyer's expense. SM ProAudio will inform the buyer of any such circumstance. If the buyer fails
to submit a written repair order within 4 weeks after notification, SM ProAudio will return the unit
C.O.D. with a separate invoice for freight and packing. Such cost will also be invoiced separately
when the buyer has sent in a written repair order.

5 WARRANTY TRANSFERABILITY
This warranty is extended exclusively to the original buyer (customer of retail dealer) and is not
transferable to anyone who may subsequently purchase this product. No other person (retail
dealer, etc.) shall be entitled to give any warranty promise on behalf of SM ProAudio.
6 CLAIM FOR DAMAGES
Failure of SM ProAudio to provide proper warranty service shall not entitle the buyer to claim
(consequential) damages. In no event shall the liability of SM ProAudio exceed the invoiced
value of the product.
7 OTHER WARRANTY RIGHTS
This warranty does not exclude or limit the buyer's statutory rights provided by national law, in
particular, any such rights against the seller that arise from a legally effective purchase contract.
The information contained in this manual is subject to change without notice. No part of this
manual may be reproduced or transmitted in any form or by any means, electronic or mechani-
cal, including photocopying and recording of any kind, for any purpose, without the express writ-
ten permission of SM ProAudio.
ALL RIGHTS RESERVED © 2001 SM ProAudio
SM Pro Audio
720 Glenhuntly Rd
Caulfield South
Melbourne, Victoria
Australia 3162
PH- [phone]
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