Specifications

Wheatfield AudioWheatfield Audio HA-1 Owners ManualHA-1 Owners Manual
8/30/00 Page 7
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.
We will make one exception to this rule, however. That exception is the tubes.
You may replace the tubes with others OF THE SAME OR ELECTRICALLY
EQUIVALENT TYPE if you desire, without endangering your warranty.
We use some very high quality tubes in the HA-1. Specifically:
The voltage amplifier tube is a JJ/Tesla ECC82, a current production type that is among
the best ECC82/12AU7 types available – better than many NOS American 12AU7’s.
However, if you are a connoisseur of 12AU7 types, or are just curious if you can hear the
difference between the JJ and a Telefunken or RCA “clear top”, go ahead and give it a
spin.
The output tubes are a special NOS computer triode, the 7044. We have secured a good
quantity of these tubes, but they are no longer manufactured. NOS 7044 tubes are
available in the marketplace from a couple of manufacturers. If you’d like to try
something different, the 7119 and E182CC tubes are acceptable substitutes, and are easier
to find than 7044’s. There is a good supply of Amperex 7119 tubes in the marketplace,
and you may find other European brands of E182CC tubes (though many will be made by
Amperex).