Wheatfield Audio HA-1 Headphone Amplifier / Pre-Amp Owners Manual
Wheatfield Audio HA-1 Owners Manual Contents Contents....................................................................................................................... 2 Safety .......................................................................................................................... 3 Unpacking, Setup, and Connection............................................................................... 4 Unpacking the amplifier ................................................................
Wheatfield Audio HA-1 Owners Manual Safety The HA-1 is a tube 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, tubes get hot.
Wheatfield Audio HA-1 Owners Manual Unpacking, Setup, and Connection Unpacking the amplifier Carefully unpack your HA-1 amplifier. Inside the package, you will find the amplifier, a power cord, and this manual (guess you already found that, huh?) It’s always a good idea to save the original packing material. Checking the tubes The HA-1 is shipped with the tubes preinstalled.
Wheatfield Audio HA-1 Owners Manual Listening with the HA-1 and headphones It’s best to start out with the volume control knob turned all the way down (counterclockwise) until you’re familiar with the HA-1. 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-1 Owners Manual Replacing Tubes Tubes don’t last forever, so you can expect to replace the tubes from time to time. We have operated the HA-1 for more than 2500 hours, with no noticeable degradation of the tubes. We expect that the tubes will last between 4,000 and 10,000 hours before needing replacement. That’s about an hour of listening per day, for ten to twenty years. Of course, your mileage may vary.
Wheatfield Audio HA-1 Owners Manual Tweaks We think that the HA-1 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-1 Owners 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. As a Headphone Amplifier Description Noise: TBD Single-ended, OTL, class-A triode amplifier Maximum output voltage (5% THD): 600 ohm load: 13V RMS 32 ohm load: 1.
Wheatfield Audio HA-1 Owners Manual Schematic Diagram 8/30/00 Page 9
