The VAC Auricle Triode Preamplifier Operation & Maintenance Information Valve Amplification Company Manual issued 02/19/2004
CAUTION DO NOT REMOVE THE COVER UNLESS THE UNIT IS COMPLETELY UNPLUGGED - ALL CONNECTIONS MUST BE REMOVED - THEN WAIT 15 MINUTES BEFORE REMOVING THE COVER. DO NOT CONNECT OR OPERATE UNLESS THE COVER IS FULLY INSTALLED. LETHAL VOLTAGES ARE PRESENT WITHIN THE CHASSIS. DO NOT OPERATE THE UNIT IF IT IS WET. VACUUM TUBES BECOME HOT ENOUGH TO CAUSE SERIOUS BURNS. NEVER TOUCH A TUBE WHEN THE UNIT IS ON. IT MAY TAKE SEVERAL MINUTES FOR THE TUBES TO COOL DOWN AFTER THE UNIT IS SWITCHED OFF.
VAC AURICLE PREAMPLIFIER Features: S S S S S S S S S All triode vacuum tube audio circuitry Passively equalized phono stage Triple shielded C-core power transformer Full tape loop Mono switch for minimizing noise from vintage records Remote control No loop feedback High input impedance, low output impedance Regulated filament supply CARE OF CHASSIS VAC chassis are aluminum for superior electromagnetic performance. The chassis is finished in a durable powder coat paint.
UNPACKING & ASSEMBLY The Auricle Preamplifier is shipped with the vacuum tubes installed. Should the need ever arise to replace the tubes, follow all of the safety directions contained in the beginning of this manual. INSTALLATION 1) Provide adequate ventilation. 2) Do not operate on carpet or any other surface that might block air flow. 3) The chassis will become warm in normal use. 4) Do not allow the chassis to touch any metal parts, such as the frame of an equipment rack.
INPUTS (back panel) Three pairs of RCA jacks accommodate unbalanced line level sources. These are labeled "L1" through "L3". One pair of RCA jacks accommodate the monitor return from a tape deck. If you do not have a tape deck, these jacks can be used as an additional line level input. One phono input is provided for MM or ‘highouput’ MC cartridges. The ground lead from the turntable should be connected to the binding post located by these jacks.
OPERATION Turn the "Volume" control fully counterclockwise. Mute is automatically engaged when switching on the unit. Allow the preamplifier to warm up for a minute before you un-mute the unit; failure to wait can cause a transient to be sent through your power amplifier that might cause damage to your loudspeakers. As with all high fidelity products, the sound characteristic of the VAC changes somewhat as it warms up. Best sound will be achieved after about 15 minutes of operation.
FRONT PANEL CONTROLS Although most of the front panel controls (Volume, Power, Mute) are self explanatory, VAC has outfitted this unit with several advanced features which bear further description: Mute: Toggles between the "Mute" and "Operate" condition. When muted, the indicator light is illuminated. Power: Turns the unit off and on. Mono: Causes the left & right channels to be electrically added.
REMOTE CONTROL The remote control allows for wireless adjustment of MUTE and VOLUME. The remote wand is powered by two "AAA" batteries. These should be of the alkaline type. You will need to install them in the wand before using the remote. Since batteries can leak, they should be removed from the wand if it is not going to be used for an extended period of time.
REPLACEMENT OF LOW LEVEL TUBES We strongly recommend that you use only tubes specifically selected and tested by VAC for this application. Before replacing tubes, all power must be turned off and all cables disconnected. Allow 15 minutes for the tubes to cool down before removing the top cover. Install new tubes of the appropriate types firmly in their sockets, noting the location of holes in the socket and pins of the tubes, taking care to make sure that pin pattern corresponds to holes in tube socket.
TIPS & ADVICE SECTION A Word About Tubes in General It is true that each brand of tube sounds different in a particular high resolution circuit. This is because no two manufacturers make a tube type in quite the same way, and the central tendencies of the performance parameters will differ slightly with each maker. To emphasize the point, examine the plate structure of any two 6SN7 from different manufacturers will probably find that they may not even the same shape and size.
VAC AURICLE PREAMPLIFIER SPECIFICATIONS (typical) Type: Vacuum tube triode preamplifier with integral triple-shielded power transformer, remote control for volume & mute (manual only version available by special order), and passively equalized MM phono input.
WARRANTY Your equipment is warranted for a period of thirty (30) days from the date of purchase. In addition, if the registration form is received by VAC along with a copy of your sales receipt from an authorized VAC dealer within this thirty days, a service contract will be extended to cover your equipment for three (3) years (tubes excepted). This warranty applies only to units sold in the United States of America through authorized VAC dealers. It covers factory service and standard return shipping.
