The Exposure 7 Pre-Amplifier

This audio pre-amplifier of exceptional sound quality is designed for zero crosstalk between channels.  When used in its dual form with the Exposure 9 professional monitor pre-amp supply and Exposure dual 4 regulated power amplifier, the ultimate goal of total channel separation throughout the amplification chain is achieved.  This has the obvious benefits of preserving the stereo information as it was originally recorded.  Exposure produce the only range of amplifiers that currently offer this most obvious of advantages.

There are two types of 7 pre-amplifier available, the "Single type" and the "Dual type".  The only difference is in the number of power supplies required to make the pre-amp operative.  An additional DC lead is required for the dual type and a single type may be "upgraded" to a dual type when improving a system.  This can either be carried out by your dealer or by returning the pre-amplifier to the factory.  The "gram" input is selectable for moving magnet and moving coil cartridges by a switch on the rear panel and has a two stage passive RIAA equalisation circuit for greater accuracy and headroom.  Each channel of the pre-amplifier is on a separate board for total channel separation but are linked for power supply purposes in the "single" type.  There are no "plug in" boards as these can vibrate in use and after a period of time result in improper and dirty contacts and so degrade sound quality and reliability.

The two high level line inputs are taken directly from the input sockets on the rear panel to the high quality selector switch and then on to the board, so that they do not interfere with the gram input.  There is no tape monitor circuit available as this would involve putting a switch between the main output of the pre-amp and the power amplifier.  This clearly would degrade the performance, however if this function is desperately needed it can be created by the use of the "EXPANDER" being inserted between the pre & power amplifier.

The Exposure 7 pre-amplifier whilst being internally regulated requires an external +/- 24V regulated power source.  This can be either from one of the two power amplifiers, which offer internal pre-amplifier supplies, or for greatly improved performance one of the two types of Exposure stand alone supplies can be used.  For complete independence of channels you will need to use at least 2 x 6 mains power supplies or the 9 professional monitor supply.

Both gram inputs and the main output utilise the same custom made gold plated phono sockets found on the power amplifiers.  This provides the correct electro-mechanical link created when the supplied phono-phono lead is used to connect the two units together.  Other types of phono-phono lead will create a frequency imbalance and cause a rise in distortion which will adversely affect the attainable performance.

The Exposure 6 Pre-Amplifier Mains Power Supply

This unit provides a regulated +/- 24v DC power source for powering the Exposure 7 pre-amplifier.  It has a high current capability which is derived from a custom designed and made 80VA mains transformer, along with two large reservoir capacitors which are again of our own design.  It has two parallel outputs and will power the dual type pre-amplifier but will not provide independent channel working.  This requires the use of at least 2 x 6 MPS or preferably a 9 PMS.  It is protected from short circuit and thermal overload.