T L Audio User Manual Ebony Series A3 Mono Processor TL Audio Limited, Letchworth, England. Tel 01462 492090, Fax 01462 492097. www.tlaudio.co.uk email: info@tlaudio.co.
CONTENTS INTRODUCTION ......................................................................................................................................... 3 WHY CLASS-A?............................................................................................................................................ 4 WHY TUBES?................................................................................................................................................ 4 WHY BALANCED I/O?.....................
Metering:................................................................................................................................................ 23 Power Requirements: ............................................................................................................................ 23 Dimensions: ........................................................................................................................................... 23 SERVICE ............................................
INTRODUCTION The TL Audio Ebony Series of audio processors are a sleek looking range of discrete Class A processors designed to heighten your audio experience; they use signal paths constructed from discrete transistor “Class A” circuits, with switchable variable drive tube stages, putting you in control of how ‘creamy’ or how ‘cool’ your unit sounds. These techniques provide very high quality, uncoloured audio, with the option to add valve warmth at the touch of a button.
The Equaliser has 3 bands. The HF and LF controls are shelving whilst the mid control is a swept, peaking filter. Comprehensive switching (via relays) allows the A3 to be configured with the equaliser pre or post the compressor, or with the equaliser in the sidechain, for deessing or frequency variable compressor effects. A VU meter is provided, which can be selected to either input or output signals. It may also be selected to display the compressor Gain Reduction.
warming to crunchy overdrive, with a single control. The signal level through the valve is displayed by the variable intensity “Drive” LED and the “Peak” LED. Where instrument inputs are present on the Ebony models, dedicated valve input stages are used. Switchable to high or low sensititivity (and impedance), these input stages represent the ultimate quality for the first stage of instrument amplification.
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PRECAUTIONS The T L Audio Ebony Series units require very little installation, but like all electrical equipment, care must be taken to ensure reliable, safe operation.
INSTALLATION AC Mains Supply. The unit is fitted with an internationally approved 3-pin IEC connector. A mating socket with power cord and mains plug is supplied. All mains wiring should be performed by a qualified electrician with all power switched off, and the earth connection must be used.
Line Input. A second 3-pin XLR connector is provided for connection to a line level source. The signal may be balanced or unbalanced, and connections may also be made as follows: Balanced inputs: - Pin 1 = Ground (screen). - Pin 2 = Signal Phase (“+” or “hot”). - Pin 3 = Signal Non-Phase (“-” or “cold”). Unbalanced inputs: - Pin 1 = Ground (screen) - Pin 2 = Signal Phase (“+” or “hot”). - Pin 3 = Signal Ground.
- Screen = Ground. Unbalanced equipment may be interfaced with the processor insertion point, by wiring the plugs with ring and screen connected together. The insertion point is “half normalled”, i.e. a plug inserted into the Send socket will provide an additional signal output, without breaking the signal flow within the processor. When a plug is inserted into the Return socket, however, the internal signal is interrupted and replaced with the insertion return signal. Output.
OPERATION Input Stage. The input gain control sets the level of the mic, line and instrument signals into the Ebony A3. The 2-position button above the input gain and ‘Tube Warmth’ knob selects the signal source. Input choices are ‘Mic’ (for dynamic or most ribbon microphones and condenser microphones that require phantom power), ‘Line’ and ‘Instrument’. For condenser microphones, you should also press the 48V button to activate phantom power.
30dB Pad. Occasionally – when using sensitive condenser microphones – the source signal may be too loud for the input preamp. In this situation, to avoid any overloading or distortion of the mic preamp stage, the 30dB pad can be used to reduce the input gain to a more manageable level. The 30dB pad only applies to the microphone input. 90Hz Filter. The high pass filter switch restricts the low frequency response of the preamp, to effectively remove rumble of LF noise from the signal.
of an audio signal. This is known as reducing the “dynamic range” of that signal and is a powerful tool for an engineer helping to avoid overloading, distortion problems as well as raising the level of the quieter parts of the audio signal.
extent as the Soft knee is more gradual around the Threshold point. Unlike some compressors, the Threshold control on TLA units including the Ebony A3 starts at a ‘zero point’ value in the counter-clockwise position, and decreases to a ‘minus’ value as you rotate the control clockwise. The reason for this is as you turn the Threshold control on the Ebony A3 clockwise (i.e. towards the negative region) then the degree of compression will increase.
Knee. The Knee switch enables the Ebony A3 to be operated in two different modes - soft Knee or hard Knee. Soft knee mode offers a gentle compression curve around the threshold point, and is traditionally employed to yield a more subtle, musical type of compression effect. The hard knee setting causes the full compression ratio to be applied immediately the signal has passed the threshold point, so tends to produce more pronounced and severe compression. Gain Make Up.
LF Band. The LF (Low Frequency) band of the equalizer has a shelving characteristic - i.e. it extends from the selected frequency to the extreme low frequency limit of the equaliser’s response. The cut or boost is controlled by a continuously variable, centre-dented, rotary knob up to 15dB of cut and boost is available. The slope of the shelf is 12dB/octave. Mid Band. The Mid Frequency band has a peaking characteristic - i.e.
recorder distorting. The Ebony A3 provides a further 15dB of gain at the output fader to drive digital recorders. It is important to distinguish the difference between the output gain knob and the gain make-up knob in the compressor section. The gain make-up control is only active when the compressor is switched on, whereas the output gain control is always active but will have no effect on the compression characteristics of the signal. Digital Output. The digital output is an option for the Ebony A3.
GETTING STARTED Connections. There are various ways that the Ebony A3 can be connected into your audio system. The three most common are: a) As an instrument front end b) Connected to a channel insert point on a mixing desk c) Connected to a group or master insert point on a mixing desk To use the Ebony A3 as an instrument front end, connect the output of the Ebony A3 directly to the line (not mic) input of your console, recorder or sound card.
The optional digital output will allow high quality 24-bit A/D conversion of the Ebony A3 mono output on a coaxial SPDIF connector. The DO-2 can feed directly into digital recorders such as Digital Multitrackers, Hard Disk Recorders, DAT Recorders, Minidisk and CD-Recorders, bypassing any A-D conversion stages on the way. When connecting the DO-2’s SPDIF output it is advisable to use cables less than 5 metres in length and of high quality.
each control to see how it affects the sound. If in doubt, aim to use compression gently as it can be difficult to compensate for over-compression, if you later decide that too much effect was used. On the other hand there are no rules, so if extreme settings get you the effect you are after, the choice is yours. Let your ears be the guide. 8. Engage the EQ section and experiment with applying some EQ.
SPECIFICATION Mic Input: Discrete Class A circuitry from input to output (unless Tube stage In), Gain Range: +16dB to +60dB (-14dB to +30dB with pad), Maximum Input level: +10dBu (without pad), +30dB (with pad), Frequency Response: 10Hz to 40KHz, +0, -1dB, @ 40dB gain, Distortion (THD + Noise): 0.035%, 20Hz to 20KHz @ 40dB gain, Noise (EIN): -127dBu unweighted, 22Hz to 22KHz, 150 ohm source termination.
Insertion Point: Pre Compressor and EQ, Balanced, separate Send and Return TRS jack sockets, Nominal Level: 0dBu, Noise -85dBu, 22Hz to 22KHz. Output: Maximum Gain +15dB, Maximum Level: +22dBu (2Kohm load), +26dBu (10Kohm load), Noise at minimum gain: -90dBu (22Hz to 22KHz). Tube Stage: Typical Distortion: 1% to 10%, depending on “Drive” level, predominately second harmonic, Noise: -80dBu (22Hz to 22KHz), output gain @ 0dB.
Mid: +/-15dB, swept 150Hz to 7KHz, Q = 0.7, HF: +/-15dB @ 12KHz, shelving, “Pre” and “Sidechain” (Compressor) switches. Metering: Tube “Drive” LED: Variable intensity over 10dB level range, typically corresponding to 1% to 5% THD. Tube “Peak” LED: Dependant on level and drive, typically corresponding to 10% THD. Output “Peak” LED: +19dBu on output. VU Meter: Switchable to Input, Ouput or Gain Reduction. Nominal calibration: 0VU = +4dBu. +10dB switch calibration: 0VU = +14dBu.
SERVICE Should the unit require service, it must be taken or posted to an authorised dealer with a description of the fault. Please retain the original packing for possible future use, and ensure the unit is suitably protected during transit. The manufacturer cannot accept responsibility for damage caused during transportation. This equipment is supported by a limited warranty for a period of one year from the date of purchase.
