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ASP4 4 Channel Microphone Preamplifier

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ASP4 4 Channel Microphone Preamplifier

£660.00 
(£550.00 + VAT)


Analogue Audio Pure Sound Quality

The ASP 4 is a 4 channel microphone preamplifier in a 1RU case size, with low distortion («0.005%), noise floor (<-100dB) and EIN (<-125dB) the audio performance is exceptional.

We guarantee the lowest prices on Formula Sound products. In the unlikely event that you find the ASP4 4 Channel Microphone Preamplifier at a cheaper price elsewhere let us know and we guarantee to beat it.

On the front panel there are controls for phantom power, LF filter, volume and mute. There is an LED meter to indicate level and a clip indicator. The LED meter indicates the level after the input amplifier but before the volume control. The clip indicator will light if the level is above +18dB at the volume control.

On the rear panel Inputs and outputs are on balanced XLRs which can be strapped for unbalanced operation if required. The gain is adjustable over a range of 46dB and there is a switch to select line level input if a high level input is required. Also on the back panel is a phase reverse switch, both line and phase switches have LEDs on the front panel to indicate status.

Phantom power is 48V as standard but there is an internal adjustment to set to 18V if required.
The LF filter is set to 70Hz with a 24dB/octave slope which will remove most low frequency noise and rumble. There is an internal adjustment to select one of four other frequencies if required (35Hz, 50Hz, 110Hz or 150Hz)
The mute switch will reduce audio to the noise floor. The volume control full down will perform the same as mute with the audio reduced to the noise floor «-100dB).
The audio signal processing is entirely analogue with a transistor input stage to give low noise and distortion.
A linear power supply helps to avoid RFI problems that can be associated with switch mode power supplies.

ASP4 Technical Specification
Frequency Response: 20Hz - 20Khz +1- 0.5 dB
Distortion THD + Noise @ 1Khz: O/P Level OdBu <0.005%
Noise 20Hz - 20Khz: EIN < -125dBu
Noise floor <-100dB
Inputs: Electronically balanced, connect negative to screen for unbalanced use.
Input impedance
Balanced: 20K Ohms
Unbalanced: 10K Ohms
Clip indicator: Indicates @ +20dBu
Phantom power: 48V but may be internally set to 18V, separate setting for each channel
Outputs: Electronically balanced, connect negative to screen for unbalanced use
Source impedance: 100 Ohms
Minimum load impedance: 600 Ohms
Gain Range: 46dB range on back panel adjustment
Line switch: 30dB reduction in gain, gain pot adjustment necessary to set OdB
LF Filter: 70Hz with 24dB/Octave roll off, may be set internally to anyone of 4 other roll off frquencies of 35Hz, 50Hz, 110Hz or 150Hz on each channel
Mute: <-100dBu
Indicator LEDs: 5 LED level meter (-10,-5,0,+3,+6dB), Clip, Line and phase reverse LED's
Power: 220V-240V (Internally switchable to 11OV). IEC Mains connector. mains fuse 250mA slow blow
Finish: Front and Rear panels - Black anodised aluminium with silver legend. Case - Black plastic coated steel
Dimensions: 19 inch rack mounting, 1RU. Width 482mm (19 inch) Depth 200mm (7.9 inch) Height 44mm (1.75 inch)

Download ASP4 Users Instruction Manual

Rating: 4 4/5 based on 2 customer ratings
Reviews

Formula Sound ASP4 4 Channel Microphone Preamplifier - formulasounddirect.com



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