Wheatfield Audio HA-2 Headphone Amplifier User's Manual
Wheatfield Audio HA-2 User's Manual Contents Safety ............................................................................................................................... 3 Unpacking, Setup, and Connection ................................................................................. 4 Unpacking the amplifier............................................................................................... 4 Installing the tubes ....................................................................
Wheatfield Audio HA-2 User's Manual Safety The HA-2 is a tube headphone amplifier. As such, there are some safety precautions that you need to observe. ! CAUTION: DANGER: HOT SURFACES. KEEP COMBUSTIBLES AWAY FROM TUBES. DO NOT BLOCK AIR FLOW AROUND AMPLIFIER. TO PREVENT ELECTRIC SHOCK, DO NOT REMOVE COVER. NO USER-SERVICEABLE PARTS INSIDE. REFER SERVICING TO QUALIFIED PERSONNEL. First, the tubes are hot… really hot.
Wheatfield Audio HA-2 User's Manual Unpacking, Setup, and Connection Unpacking the amplifier Carefully unpack your HA-2 amplifier. Inside the package, you will find the amplifier chassis, the tubes (packed separately), a power cord, and this manual (guess you already found that, huh?) It’s always a good idea to save the original packing material. Installing the tubes There are three different tubes used in the HA-2. Note the tube types, which are printed on the tube boxes.
Wheatfield Audio HA-2 User's Manual Listening with the HA-2 It’s best to start out with the volume control knob turned all the way down (counterclockwise) until you’re familiar with the HA-2. Turn the amp on, using the font panel power switch. It’s OK to leave your headphones plugged in when you turn the amplifier on and off – there is very little turn-on/turn-off “thump” generated, since the amplifier warms up slowly.
Wheatfield Audio HA-2 User's Manual The Tubes Tubes don’t last forever, so you can expect to replace the tubes from time to time. If you notice degradation of the sound, or a lowering of the volume, it may be time to replace the tubes. You can replace the tubes yourself. Just find a high-end Hi-Fi shop that sells tubes, or look on the internet – there are a number of companies that sell tubes on-line for very reasonable prices. Purchase the same tube types as what was originally supplied in the amplifier.
Wheatfield Audio HA-2 User's Manual Tweaks We think that the HA-2 is a fine amplifier, right out of the box. It was designed with what we believe is an optimal combination of components. That being said, many audiophiles are never satisfied with any piece of equipment until they’ve “tweaked” it in their own special way. We don’t recommend that you make changes to the amplifier. If you choose to modify the amp or change any components, your warranty is void, so you’re on your own.
Wheatfield Audio HA-2 User's Manual Specifications Note: Specifications listed are typical, and are derived from measurements on actual amplifiers. There will be some variation from one amplifier to the next. Specifications are subject to change without notice. Description Single-ended, OTL, class-A triode amplifier Single voltage amplifier stage, single cathode follower stage DC-coupled input; capacitor-coupled output.
Wheatfield Audio HA-2 User's Manual Schematic Diagram 11/19/99 Page 9
