VAC Phi 200 User Manual

F

The VAC Phi Two Hundred

Stereo Beam Power Amplifier

Operation & Maintenance Information

Valve Amplification Company

200

Manual issued 01/02/2009

Revised 03/11/2009, 01/21/2010

CAUTION - SAFETY NOTICES

THE AMPLIFIER CONTAINS NO USER SERVICEABLE PARTS. DO NOT REMOVE THE BOTTOM PLATES
OR CHASSIS COVERS. LETHAL VOLTAGES ARE PRESENT WITHIN THE CHASSIS. DO NOT OPERATE
THE UNITS IF THEY ARE 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. IT IS STRONGLY RECOMMENDED THAT THE TUBE COVERS BE LEFT IN PLACE AT ALL
TIMES.

Never touch a tube if the glass is broken. The internal structures carry high voltage and could present
a serious, possibly lethal shock. If a tube breaks, unplug the amplifier and wait 30 minutes, then
remove the tube.

Keep flammable objects away from the amplifier.

DO NOT LEAVE THE AMPLIFIER UNATTENDED IN OPERATION.

THE AMPLIFIER IS HEAVY. IT IS ADVISABLE TO HAVE ASSISTANCE IN UNPACKING, MOVING, AND
SETTING UP. BE SURE TO USE PROPER LIFTING TECHNIQUES TO AVOID BACK STRAIN AND INJURY.
BE CERTAIN TO INSTALL IT IN A SECURE LOCATION FROM WHICH IT CAN NOT FALL OR TIP OVER.

Provide adequate ventilation - allow at least 3 inches above and to each side.

Do not place in a completely enclosed cabinet. Do not stack other equipment on top of the VAC
unit.

Do not operate on carpet or any other surface that might block air flow.

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INDEX

Introduction
Installation - Stereo
Mono Connections / Mono Switch (option)
Operation
Installing New Output Tubes
Biasing & Checking Output Tube Condition
Replacement of Low Level Tubes
Care Of Chassis
Tips and Advice

A Word About Tubes in General
Output Tubes
Low Level Tubes
Impedance Matching
Grounding

Tuning Your System
Specifications
Footnotes
Warranty & Registration Form

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INTRODUCTION

The Phi 200 is a unique power amplifier, and one of the most vivid and detailed in VAC’s history,
second only to the larger Phi 300.1. Featuring a new direct-coupled input & driver circuit, extremely
fast and vivid sound is achieved from both single-ended and balanced sources.

The Phi 200 may be used as a 100+ watt/channel stereo amplifier, or can be connected as a 200+
watt monophonic amplifier.

The Phi 200 is designed not to the latest fad but to substance, for the highest possible sound quality.
Time spent familiarizing yourself with this manual will be well rewarded.

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INSTALLATION - STEREO USE

01)Install the vacuum tubes. Each tube or its box has a “V” number, which corresponds to the
labels on the top plate of the amplifier; these indicate where each tube should be installed.

Fit each tube into the matching socket.

When inserting and removing tubes, handle them by their bases, not by their glass bulbs.

Note that there is a locator pin on the octal (eight contact) tubes that indicates proper
alignment.

02)Connect input cables, either RCA types for unbalanced sources, or balanced XLR types for
balanced sources.

03)Verify that the two “Balance / Single-Ended” switches are set to the same desired position.
Set the input type switch to XLR (for balanced input) or RCA (for single-ended input).

04)If your amplifier is fitted with a MONO SWITCH, ensure that it is set to “STEREO”.

05)Connect the speaker cables; the black lead goes to “-“ or “Ground”. The red lead goes to
“+” or “Positive”. Follow the labels for the impedance that best matches your loudspeakers.

06)Connect a12 volt trigger cable into the socket on the back panel if desired; this allows the
amplifier to be turned on and off by an external device.

07)Provide adequate ventilation - allow at least 3 inches above and to each side.

08)Do not place in a completely enclosed cabinet. Do not stack other equipment on top of the
VAC unit.

09)Do not operate on carpet or any other surface that might block air flow.

10)The chassis will become hot in normal use.

11)Do not allow the chassis to touch any metal parts, such as the frame of an equipment rack.
This might create a parallel ground path that could degrade the sound of your system.

12)Connect the power cord to the power source indicated on the rear panel (will be either
100, 120, 220, or 240 volts AC). Voltage conversions must be done at the factory of by
an authorized VAC importer.

13)Avoid power conditioners that float the ground pin.

14)Power requirements are approximately 600 watts. Pay close attention to power quality, and

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be aware that different power cords can alter the sound.

15) Check the bias settings of the output tubes when the unit is first installed and whenever a
tube is changed. It is also a good idea to verify the settings periodically, such as once a
week. Follow the bias procedure outlined later in this manual.

NOTES:

Do not remove and connect input cables or speaker cables while is amplifier is running.
Doing so risks damage to your loudspeakers or the amplifier.

Do not operate the amplifier without a loudspeaker or load resistor attached.

Do not allow anything to touch the tubes in normal operation - they become very hot.

Take care to keep everyone, especially children and pets, from being able to reach and
touch the tubes, which become extremely hot and cause serious injury.

Never touch a tube if the glass is broken. The internal structures carry high voltage and could
present a serious, possibly lethal shock. If a tube breaks, unplug the amplifier and wait 30
minutes, then remove the tube.

Keep flammable objects away from the amplifier.

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