Vox Valvetronix AD120VTH, Руководство пользователя

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he following is some information that you’ll find useful for hooking up your
Valvetronix AD60VTH or AD120VTH head. When you’re done with this,
you’ll be a smarter and better person! Plus you’ll know the correct way for
hooking up speaker cabinets in series or parallel.
In multiple speaker cabinet configurations, you will have to use a little mathematics
(Ohm’s law) in order to figure out the correct setting. Don’t worry though; it’s easier
than you might think! The formula will depend on whether you are hooking the
cabinet(s) up in series or parallel. Parallel is more common which is how the
AD60VTH and AD120VTH work.
Parallel
When using two cabinets of the same impedance in parallel, just divide the imped-
ance of one cabinet by 2. For example, when using two 8 Ohm cabinets in parallel,
set the impedance selector on the amp for 4 Ohms (8 divided by 2 equals 4). When
using two cabinets and each is 16 Ohms set the amp for 8 Ohms. Here is the
Ohm’s Law formula for connecting two speakers (or cabinets) in parallel:
Let’s take two 16 Ohm cabinets for this example:
R3 = 16 x 16 = 256 = 8 Ohms
16 + 16 32
Series
In a series configuration, all you do is add the individual impedances of the cabi-
nets. For example, if you hook up two cabinets, where each is 8 Ohms (8 plus 8),
the result is 16 Ohms. If one cab is 8 Ohms and the other is 4 Ohms, the total
impedance is 12 Ohms. There are no 12 Ohm settings on amps, so set your amp
to 16 Ohms.
R1 is the impedance of our first cabinet; R2 is the impedance of the second one
and R3 is the resulting impedance when they are hooked-up together.
R3 = R1 x R2
R1 + R2
Using two cabinets of different impedance is a bit more complicated. Check it out…
Let’s take one 16 Ohm cabinet and one 8 Ohm cabinet for this example:
R3 = 16 x 8 =
128
= 5.33 Ohms
16 + 8 24
If the minimum impedance of your amp is 8 Ohms do not use it with a 16 and 8
Ohm cabinet in parallel. If the minimum impedance or your amp is 4 Ohms, you are
OK to go.