Two Notes Live - Manual (Page 11)

Part 2
Warning regarding 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 recommended to 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 load box).
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 embedding a load. The main parameter of the
load box is its impedance, expressed in Ohms. An 8 Ohms load box has to be plugged to the 8 Ohms speaker out
of the amplifier. The power sent to the load is changed into heat, so please follow the cooling recommendation
of the load box, otherwise overheating may cause damage, both to the loadbox and the amp.
The TORPEDO Live is a loadbox. This term indicates that the TORPEDO Live 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 Live 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 ampilifier to a proper load
(speaker cabinet or load box). TORPEDO Live, once powered up, is such a
load. Please note that you always have to power up the TORPEDO Live before
your amplifier.
Two Notes Audio Engineering TORPEDO Live 11