Epifani American Tweed 4x10, Руководство пользователя

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When connecting speaker cabinets to an amplifier, it
is important to never exceed the minimum impedance
for which the amplifier is rated. Many bass amps, like
the Epifani Piccolo, for instance, have a minimum
impedance rating of 4 Ohms (Ω).
In this case, if the total impedance of the speaker
cabinets connected to the amplifier is less than 4
Ohms, it could cause the ampifier to overheat and the
protection circuitry to shut the amplifier off.
Using a single 4 Ohm or 8 Ohm cabinet will not
exceed the minimum impedance of most amps.
When combining two speakers, make sure they are
both designed for 8 Ohm operation. Combining two
8 Ohm cabinets will give you a total impedance of 4
Ohms.
Do not combine two 4 Ohm cabinets unless your amp
has a minimum impedance of 2 Ohms, like the Epifani
UL 901 [1000W].
You can use your Epifani American Tweed cab(s) with
other speaker cabinets. But watch out! Not all cabs are
created equal.
When using other cabinets with your American
Tweed, be sure the others are in phase. You can easily
test the polarity, or phase, of those speakers using a
9 volt battery (the same battery used in most active
basses). With this test you can make sure they are all
moving in the right direction (forward!).
What does “out of phase” mean?
Sometimes, when you daisy chain two cabinets, you
will note a lack of bass resonse. Typically, this means
that one of the cabinets is “out of phase,” meaning its
speaker is moving backwards when the other moves
forward. This will cause them to cancel each other
out. You can readily notice this when a single cabinet
has more bass and better response than when two are
connected.
How to test
Here’s how to verify phase: Take a 1/4-inch cable
and connect one side to the cabinet. Touch the tip of
the the other end of the 1/4-inch jack to the “+” of
a 9-volt battery, and touch the shaft to the “-” of the
battery.
All the speakers should move forward when this
connection is made. If it does, all the speakers are in
phase. If one or more speakers move backwards, you
have a cabinet that is wired out of phase. The problem
can easily be corrected by a speaker technician.
Control Panel The Tao of Impedance
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One 4 Ohm or 8 Ohm cabinet Two 8 Ohm cabinets = 4 Ohms total impedance