Two Notes Reload - Manual (Page 11)

Part 2
Recommendation on the proper use of
a loadbox with a tube amplifier
1 What is a loadbox?
In the normal use of a tube amplifier, it is highly recommended that you always connect its power
output to a speaker cabinet prior to powering it up. The speaker cabinet (4, 8 or 16 Ohms) must
always be connected to the corresponding speaker output of your amplifier. Not doing so can lead
to partial or complete destruction of the output stage of the tube amplifier.
Most tube amplifier makers protect their products with fuses or other protection systems, but some
amplifiers still remain not or insufficiently protected. It is impossible to predict the behavior of all the
amplifiers on the market in case of use without a load (a speaker cabinet or a loadbox).
The electronic term that describes the speaker cabinet with respect to the amplifier is the "load":
we say the cabinet "loads" the amplifier. The term "loadbox" fits any product that embeds a load.
The main parameter of the loadbox is its impedance, expressed in Ohms. An 8-Ohm loadbox must
be plugged to the 8-Ohm speaker output of the amplifier.
The power sent to the load is turned into heat, so please follow the cooling recommendation of
the loadbox — otherwise overheating may cause damage, both to the loadbox and to the amplifier.
The Torpedo Reload is a loadbox. This term indicates that the Torpedo Reload is a load which can
electrically replace the speaker cabinet while dissipating (transforming into heat) the power coming
out of the amplifier.
The embedded load in the Torpedo Reload is a reactive one: it embeds a specific circuit to
simulate the complex impedance of a real speaker. This kind of system is widely used in the industry
to silently test amplifiers.
Always connect the speaker out of your tube amplifier to an appropri-
ate load (speaker cabinet or load box). Torpedo Reload, once pow-
ered up, is such a load. Please note that you must always power up
the Torpedo Reload before your amplifier.
Two Notes Audio Engineering Torpedo Reload 11