SM Pro Audio TB101 User manual

SMProAudio
Operating Manual - TB101/202
Version 1.0 Feb 2004
www.SMProAudio.com

2Safety
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.

3Features - Foreward
SM TB101/202 Main Features
Professional, multi-purpose pre-amplifier channel strip for studio applications
- High quality microphone/instrument pre-amplifier
- hand tested 12AX7 tubes used
- Switchable Phantom Power per channel
- Switchable Phase reversal per channel
- High quality Optical Compressors
- Independent EQ circuitry
- Input gain control per channel
- -20dB pad per channel
- Master Volume control
FOREWORD
Dear Customer,
Thank you very much for expressing your confidence in SM ProAudio products by purchasing
this unit. The SM TB101/TB202 units have been designed to be used as a standard tool for
home/pro studios. 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

4Table of Contents
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 power
3.3 Audio connections
4. FRONT PANEL CONTROLS
4.1 Input stage
4.2 Compressor stage
4.3 EQ Stage
4.4 Output stage
5. REAR PANEL CONTROLS
6. APPLICATION
6.1 Using the SM TB101/202
7. SPECIFICATIONS
8. WARRANTY

5Introduction - Design Concept
1. INTRODUCTION
In purchasing the new SM TB101/202, you have acquired a tube microphone pre-amplifier chan
-
nel strip of high class that meets many of the demands of the home/pro studio.
For your reference in this manual, the TB101 and TB202 units are either single or dual channel
designs of the same circuitry. The TB101 is the single channel unit that is half rack size, whereas
the TB202 is a dual channel unit, just like 2 x TB101’s side by side.
The market size for digital audio interfaces and computer based digital editing has increased in a
massive way. With systems available at very low prices, more and more users are utilizing this
technology. One of the main problems with many of these systems is the input stage only
consisting of unbalanced line inputs or very low (or no mic pre) gain structure for the balanced
input stage and the unavailability of Phantom power.
The TB101/202 comes to the rescue with either one or two channels (TB101 or TB202) of bal-
anced input with a tube microphone preamplifier, optical compression, 3 band EQ, Phantom
power, phase reverse switch, and for output volume for each channel. Both the TB101 or TB202
units can now solve many of the connectivity issues which are raised in a large range of situa-
tions, whether in the home or professional studio.
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. The components used in the SM TB101/202, are excep
-
tional. They boast extreme linearity and very low distortion characteristics. The tubes used are
hand selected and tested for optimum performance.
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.

6Installation
3. INSTALLATION
Your SM ProAudio SM TB101/202 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 Desktop TB101 - or - Rack Mounted TB202
The TB101 is a compact half rack-mount sized unit perfect for environments with limited space.
Perfect for sitting on the desktop, the TB101 is suitable for just about any installation.
The SM ProAudio SM 202 fits into one 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 TB101/202 on high temperature devices such as power amplifiers.
3.2 Mains Power
The SM TB101/202 ship with a standard external power supply. Connect the power supply to
your mains power and to the rear of your SM TB101/202.
3.3 Audio connections
Analog inputs
Front Panel - On the front of the SM TB101/202 you will fine the 1/4” jack instrument input/s
marked ‘instrument’.
Rear Panel - On the rear of the SM TB101/202 you will find the XLR balanced microphone
input/s marked ‘Input’.
Analog outputs
Rear Panel - On the rear of the SM TB101/202 you will find both XLR balanced and 1/4”
Unbalanced jack output/s.

7Controls
4. FRONT PANEL CONTROLS
The SM TB101/202 front panel has a very simple design including; Input stage, Compressor
stage, EQ stage, and output level control stage.
4.1 Input stage
Rotary input control
The rotary input control sets the input gain level of the incoming signal.
-20dB PAD switch
The PAD switch enables or disable the PAD which reduces the input signal by 20dB. Useful if
your incoming signal is too powerful and cannot be reduced prior to insertion into the TB101/202.
LED clip indicator
The clip indicator LED illuminates when there is too much incoming signal strength.
4.2 Compressor stage
Compression on/off switch & LED Indicator
Turns the compressor stage on or off. The indicator shows the on/off status of the compressor.
Rotary compression control
The rotary compression control sets the compression ratio of the compressor. The compression
ratio expresses the difference between the input level change and the output level change. A
compression ratio of 6:1, for example, indicates that for every 6dB of level change on the input
signal there is only 1dB of level change on the compressed signal. The higher the compression
ratio, the smaller the dynamic range.
Fast/slow attack switch & LED Indicator
This switch toggles the attack setting of the compressor between fast and slow attack times. The
indicator shows the status ‘fast’ of the the attack setting. The attack setting on a compressor
determines how fast it will react to the input sound. Short attack times quickly bring down the
level of the loud, fast transients in the audio signal; long attack times let more sound through
before the compressor engages, resulting in a punchier sound.
Fast/slow release switch & LED Indicator
This switch toggles the release setting of the compressor between fast and slow release times.
The indicator shows the status ‘fast’ of the the release setting. The release setting on a compres
-
sor determines how quickly the signal level returns to its original level after the compressor has
engaged. Short release times create a more exaggerated effect ("breathing"), whereas long
release times have a more gradual, natural sound.

4.3 EQ Stage
80Hz low shelving rotary control
This rotary control allows for cutting or boosting an 80Hz low shelving EQ by approx 16dB.
1.8kHz low shelving EQ rotary control
This rotary control allows for cutting or boosting a 1.8kHz mid-frequency by approx 16dB.
8kHz high shelving EQ rotary control
This rotary control allows for cutting or boosting an 8kHz high shelving EQ by approx 16dB.
4.4 Output stage
Rotary output control
This controls the master output signal level.
5. REAR PANEL CONTROLS
Phantom power switch/s
You can enable or disable phantom power each channel of input. This is required for condenser
microphones without a battery or stand alone power supply.
Phase reversal switch
A phase reverse switch is available for reversing the phase of the signal by 180 degrees. This
can be desired in situations such as recording a snare drum from above and below the drum
simultaneously. By reversing the phase on one of your microphone signals you will achieve a bet
-
ter result, recording full range of signal without a phase cancellation occurring.
8Controls

9Application
6. APPLICATION
6.1 Using the SM TB101/202
It could not be simpler to use and operate the SM TB101/202.
Step by step:
Make your physical connections ...
Simply make your signal connections by either connecting an instrument (guitar, bass, etc) to the
instrument input on the front panel, or connecting a microphone to the XLR mic input on the rear
of the unit. Connect the output of the unit to your destination device (sound-card, recorder, mixer,
etc).
Do you need phantom power? ... or to change the phase of your input signal?
If you are using a condenser microphone that requires phantom power, select the phantom
power switch to the on position. You can also choose to switch the polarity of your signal at this
stage if required.
Set your input gain control ...
Set your input level. Adjust the input rotary control to an acceptable level. This is a good time to
check the clip indicator to ensure you are not overdriving the tube pre-amp with too much signal.
If your signal is too strong, reduce the amount with the rotary control. If you cannot reduce the
signal enough to stop the clip indicator constantly illuminating, you can enable the -20dB PAD to
assist in reducing the incoming signal gain.
Do you desire compression? ...
You can now choose to add some optical compression to your signal if desired. You can select
the compressor on/off switch to the on position. Set your attack and release switches to the
desired settings (fast/slow), and adjust the compression ratio rotary control until you are satisfied
with the result.
Do you desire EQ to tailor your sound? ...
You can now choose to EQ your signal if desired. Use the high and low shelving rotary controls
in conjunction with the mid frequency cut/boost control to tailor your sound to your desired result.
Set your output level ...
Adjust your master output level rotary control to the required amount.

10 Specifications
7. SPECIFICATIONS
AUDIO INPUTS
Mic input connector XLR balanced
Impedance 3k Ohms
Mic input gain 10dB to 60dB
Phase reversal switchable
Phantom power +48V, switchable
Instrument input con. 1/4" jack unbalanced
Instrument input gain 0dB to 45dB
AUDIO OUTPUTS
Connectors XLR & 1/4" jack
Type Balanced & Unbalanced
AMPLITUBE FREQUENCY RESPONSE
Line in 6Hz to 20Hz within 1dB
Mic in 8Hz to 20Hz within 2.5dB
COMPRESSOR
Photoresistive servo operated
Ratio minimum 1.5 to 1
Ratio maximum 10 to 1
Attack time 1mS/5mS
Release time 500mS/1500mS
EQ
Shelving high and low frequency controls 8kHz & 80Hz
Mid frequency cut/boost control (1.8kHz)
Cut boot level approx 16dB
METERS
LED -25dBu to + 18dBu
PERFORMANCE
THD (Unweighted) 0.05%
Signal to noise >90dB
Power supply rejection >98dB
POWER SUPPLY
Transformer External
Input 17v AC
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.

11 Warranty
8. 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
Warehouse 25
Roberna Business Park
26-28 Roberna St
Moorabbin 3189
Melbourne, Victoria
Australia
PH- [phone]
FAX- [phone]

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.
12 Warranty

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
Service Department
Warehouse 25
Roberna Business Park
26-28 Roberna St
Moorabbin 3189
Melbourne, Victoria
Australia
PH- [phone]
FAX- [phone]
13 Warranty