TL Audio 5050 User Manual

user manual

TL A

udio

®

Ivory 2 Series

5050

MONO VALVE PREAMP

& COMPRESSOR

TL Audio Ltd, Letchworth, Herts, SG6 1AN, UK
email: [e-mail] web: http://www.tlaudio.co.uk

CONTENTS

1 INTRODUCTION

2 PRECAUTIONS

3 INSTALLATION

3.1 A.C. Mains Supply

3.2 Audio Operating Level

3.3 Microphone Input

3.4 Line Input

3.5 Instrument Input

3.6 Output

3.7 Mounting

3.8 Rear Panel

4 OPERATION

4.1 Front Panel

4.2 Input Selection

4.3 30dB Pad

4.4 Phantom Power

4.5 Microphone Input

4.6 Line Input

4.7 Instrument Input

4.8 High Pass Filter

4.9 What is Compression?

4.10 Why Valve Compression

4.11 Overview of Compressor Operation

4.12 Threshold

4.13 Ratio

4.14 Attack & Release

4.15 Knee

4.16 Gain Make Up

4.17 Compressor On

4.18 Output Level

4.19 Bar Graph Meters

4.20 Optional DO-2 Digital Output Card

5 GETTING STARTED

5.1 Connections

5.2 In Use

6 SPECIFICATIONS

7 SERVICE

1. INTRODUCTION

Congratulations on purchasing the Ivory 5050 Mono Preamp & Compressor by
TL Audio!

The Ivory 2 Series consists of a range of hybrid valve signal processors, which
utilise low noise solid state electronics in conjunction with classic valve
circuitry to produce audio processing units offering very high quality signal
paths with the unique valve audio character. The Ivory 2 Series units offer
comprehensive control facilities, whilst remaining straightforward to operate,
and represent excellent value for money.

The 5050 is a single channel pre-amplifier, accepting a wide range of inputs,
coupled to a compressor with fully variable parameters. Twin LED bargraph
meters display output level and gain reduction. The optional DO-2 digital
output card provides 24 bit A-D conversion of the 5050 analogue output, via a
coaxial SPDIF connector. 44.1kHz and 48kHz sample rates are selectable,
and an external BNC wordclock input is also provided on the D0-2.

The block diagram of the unit is shown in Fig.1. There are three input sources

- balanced microphone via an XLR connector, balanced line input via a TRS
jack socket, and an instrument jack socket located on the front panel, where it
provides a convenient means of patching a guitar or keyboard directly into the
processor. The input stage is a hybrid valve circuit, containing one stage of an
ECC83/12AX7A dual triode valve, run from a 150V DC stabilised supply. The
input gain is governed by a centre-detented control, calibrated for 0dB nominal
gain from the line input sources at the centre and providing up to 60dB of
microphone gain. The instrument input is also controlled by the input gain
potentiometer, and will accept a wide range of sources from passive pickups
through to active guitars and keyboards. Phantom power and a 30dB pad are
provided on the mic preamp stage, and a switchable 90Hz high pass filter is
active on all three inputs.

The compressor stage offers variable control of threshold and ratio, with
switchable attack & release times and a choice of soft or hard knee
compression modes. The compressor is based around TL Audio’s trademark
transconductance amplifier stage, and also utilises the other stage of the
above-mentioned ECC83/12AX7A valve.

An independent gain make-up control is provided, to retain the subjective
loudness of a compressed signal, plus an overall master output level control.
The output control has a nominal 0dB of gain at its centre, with up to 15dB of
further gain available to achieve the high level required for some digital
recorders.

The output is via a balanced jack socket at a nominal level of +4dBu. Metering
of the output is by an 8 segment LED bargraph.

Please read this manual fully before installing or operating the 5050.

2. PRECAUTIONS

The T L Audio 5050 requires very little installation, but like all electrical
equipment, care must be taken to ensure reliable, safe operation. The
following points should always be observed:

- All mains wiring should be installed and checked by a qualified
electrician,

- Ensure the correct operating voltage is selected on the rear panel
before connecting to the mains supply,

- Never operate the unit with any cover removed,

- Do not expose to rain or moisture, as this may present an electric
shock hazard,

- Replace the fuse with the correct type and rating only.

Warning: This equipment must be earthed.

3. INSTALLATION

3.1 AC Mains Supply.

The unit is fitted with an internationally approved 3 pin IEC connector. A
mating socket with power cord is provided with the unit, wired as follows:

Brown: Live.

Blue: Neutral.

Green/Yellow: Earth (Ground).

All mains wiring should be performed by a qualified electrician with all power
switched off, and the earth connection must be used.

Before connecting the unit to the supply, check that the 5050 is set for the
correct mains voltage. The unit is internally set for 110-120V 60Hz or 220­240V 50Hz operation, and should only be changed by an authorised service
centre. The mains fuse required is 20mm anti-surge, 1AT rated at 250V. If it is
ever necessary to replace the fuse, only the same type and rating must be
used. The power consumption of the equipment is 20VA.

Warning: attempted operation on the wrong voltage setting, or with an
incorrect fuse, will invalidate the warranty.

3.2 Audio Operating Level.

The 5050 is equipped with inputs and outputs suitable for connection to a wide
variety of other audio equipment. The line level input is via a TRS jack socket,
and will support both balanced and unbalanced operation when correctly
wired. The output is also a TRS jack socket and will support both balanced
and unbalanced operation.

3.3 Microphone Input.

The microphone input is via 3 pin female XLR connector, suitable for balanced
or unbalanced microphones. The mating connector should be appropriately
wired as follows for balanced or unbalanced operation:

Balanced inputs:

- Pin 1 = Ground (screen).

- Pin 2 = Signal Phase (also known as “+” or “hot”).