AMT 97-4C, Manual

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Unless your amplifier has phantom power (see below), you will need to install a 9-volt battery inside the AMT Preamp box. Remove the screw that holds the
cover in place, attached the battery leads to the battery, and insert the battery in the battery clip. Replace the cover. Plug the microphone cable into the preamp
box. You will notice that there is a slight indentation of the end of the cable which matches a tab in the input jack on the preamp. Make sure these are lined up
when you insert the cable. There is also a lock ring on the cable. After you plug in the cable, slide the ring forward slightly and turn in clockwise. This will secure
the cable to the preamp. Be sure to unlock this ring when you unplug the cable. The cable is also the on / off switch. When it is plugged in, the system is active.
If you wish to get your system all set up, with the volume levels set, you can simply unplug the cable from the preamp to deactivate the system without needing to
change any settings or go to the amplifier to turn it off.
Cables and Inputs
Standard microphone cables are called by a variety of names: “Microphone”, “Low impedance”, “Low-Z, “Balanced Line”, and “XLR”. “Z” means “Impedance”.
These terms, along with “Balanced line” refer to the way in which the signal is passed along the cable. “XLR” is a description of the
connectors on the end of the microphone cables and the inputs on amplifiers and mixers. The only times these terms become
important to most musicians is when you need to describe to purchase or tell a sound engineer what type of cable / connections you
have or need. The P43s preamp is equipped with an XLR type balanced low-Z output jack. A standard microphone cable will have
an end that plugs into this type of jack. As mentioned above, many guitar amplifiers don’t have XLR type inputs. They typically
have ” input jacks which will require an impedance matching transformer. We encourage you to use good quality cable and
adapters. The very inexpensive ones fail with startling regularity.
Phantom Power
The P43s is a condenser-type microphone, which means it requires power in order to operate. Most PA systems and some amps are equipped with phantom
power, which means the power required to operate the microphone is supplied by the amp or PA and is conducted to the microphone by the same cable that
carries the signal from the microphone to the amp. Be sure the phantom power is turned on. Since many amps and some PA’s do no have phantom power, the
preamp uses a 9-volt battery that will supply power if needed. The phantom power overrides the battery, so you should use phantom power whenever possible to
save your battery.
Volume, Tone Controls, and Feedback
When a microphone is placed in front of or near a speaker that is producing a n amplified signal from that microphone, there is a possibility for feedback. This is
the annoyingly loud high-pitched squeal (or sometimes the low irritating hum) that amplification systems produce all too often. It is important that the speaker
be positioned so that it is pointing away from the harp as much as possible. If you need to hear the sound coming from the amp, try positioning if off to one side
and angled slightly away.. If you are in a situation when you can hear yourself adequately, position the amp in front of the harp (with the back of the amp facing
you). This is the best way to control feedback.
Either turning down the volume or adjusting the tone controls can also control feedback. In general, you can turn down the Treble controls to get rid of the high
feedback or turn down the Bass controls to get rid of the low hum. Remember that the tone controls also control the sound of your instrument; so relying on
them exclusively for feedback control can create problems. Some combination of positioning, volume control, and tone control I usually best. If you are using
your own amp or PA system, you will quickly learn what feedback sounds like and how to control it. Two things that make it hard to control are playing in a very
small room or having the speaker pointed directly at the microphone. With some experimentation, it’s usually possible to achieve the volume you want without
introducing feedback.
An amplifier or mixer with a balanced XLR input is the preferred type for use with your P43S. If you are choosing an amp to buy, you may want to look for one
with this type of input.. Please be aware that the P43s is a professional piece of sound gear designed to reproduce the natural acoustic sound of your instrument.
However, the amp you use will play a big role in determining the final sound quality you get from your system. If you are not satisfied with the sound you are
getting, you may want to invest in an amp designed for amplifying acoustic instruments. Electric guitar amps are not likely to deliver a sound that you will be
happy with.
Clamp Instructions – LS, Wi5, & System 1
The LS, Wi5 & System 1 ship complete with a clamp for flanged bell instruments such as saxophone, trumpet, and trombone bells.
These models can mount to additional instruments such as percussion, accordion, and clarinet with the purchase of optional clamps.
To mount these models on a flanged bell instrument, insert the rod from the microphone into the open hole. Tighten thumbscrew to
hold microphone rod in place. Place clamp in the palm of your hand and open the spring-loaded clamp onto the bell of the horn with bottom or underneath side
of the horns bell in the groove of the clamp.
Optional Clamping systems for LS, Wi5, System 1, ERTS, ACCX, P43S
Clarinet Clamp Bass Clarinet Clamp ERT Percussion Clamp ACCX Accordion Clamp