User's Manual

True to the Music
Radial Engineering Cabbone Owner’s Manual
7
ALT-Z (alternate impedance) input jack
The second ¼” input jack on the Cabbone is used with amps that are
equipped with multi-tap transformers and multiple outputs for various
speaker impedance requirements. For instance, you may have one
speaker that is 4-Ohms and another that is 8-Ohms. Many amps fea-
ture separate speaker outputs to accommodate these loads.
Start by connecting the 4-Ohm cabinet. Connect the amp’s 4-Ohm
speaker output to the Cabbone’s FROM AMP input and then connect
the SPEAKER 1 output to the 4-Ohm speaker cabinet. Now connect
the 8-Ohm cabinet. Connect the amp’s 8-Ohm output to the Cabbone’s
ALT-Z input and then the SPEAKER 2 output to the 8-Ohm speaker
cabinet. The ALT-Z input is a “switching” jack that automatically re-
routes the input signal when connected.
Using unmatched loads
It is important to note that most amplifiers are designed to work best at
their rated impedance. This does not, however, mean that you cannot
use alternate loads. Before connecting the Cabbone, make sure you
read the amplifier manufacturer’s specifications to ensure the speaker
connections meet the amps accepted working range.
Transistor or solid-state amps generally work differently than tube
amplifiers. With solid-state amps, lowering the load generally makes
the amp sound louder. Most solid-state amps are designed to see an
8-Ohm or 4-Ohm load. Never go below the amplifier’s rated minimum
impedance. With tube amps, lowering the load tends to drive the tubes
harder which means they will not last as long. On the other hand, a
higher speaker impedance will generally make tube amps sound less
full and punchy. Therefore unless your amp is set up with two different
speaker outlets with independent impedance options, you will have to
make decisions on where to compromise to make your system work.
Alternatively, you can change your speaker cabinet and/or wiring to
match the load. To be safe, we always recommend setting your amp’s
impedance selector switch to match the lowest speaker cabinet imped-
ance in your setup.
For more information on wiring speaker cabinets, please visit our www.
tonebone.com web page. There you will find more information on
parallel and series wiring which could be helpful when designing your
guitar amplifier system.