Yamaha A10, Service Manual

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SPEAKER SYSTEM/SUBWOOFER
A10/A12/A12M/A15/A15W
IMPOR TANT NOTICE
This manual has been provided for the use of authorized Yamaha Retailers and their service personnel. It has been assumed
that basic service procedures inherent to the industry, and more specifically Yamaha Products, are already known and under-
stood by the users, and have therefore not been restated.
WARNING :
Failure to follow appropriate service and safety procedures when servicing this product may result in per-
sonal injury, destruction of expensive components and failure of the product to perform as specified. For
these reasons, we advise all Yamaha product owners that all service required should be performed by an
authorized Yamaha Retailer or the appointed service representative.
IMPORTANT :
This presentation or sale of this manual to any individual or firm does not constitute authorization certifi-
cation, recognition of any applicable technical capabilities, or establish a principal-agent relationship of
any form.
The data provided is belived to be accurate and applicable to the unit(s) indicated on the cover. The research engineering, and
service departments of Yamaha are continually striving to improve Yamaha products. Modifications are, therefore, inevitable
and changes in specification are subject to change without notice or obligation to retrofit. Should any discrepancy appear to
exist, please contact the distributor’s Service Division.
WARNING :
Static discharges can destroy expensive components. Discharge any static electricity your body may have
accumulated by grounding yourself to the ground bus in the unit (heavy gauge black wires connect to
this bus.)
IMPORTANT :
Turn the unit OFF during disassembly and parts replacement. Recheck all work before you apply power
to the unit.
WARNING: CHEMICAL CONTENT NOTICE!
The solder used in the production of this product contains LEAD. In addition, other electrical/electronic and/or plastic (Where
applicable) components may also contain traces of chemicals found by the California Health and Welfare Agency (and possibly
other entities) to cause cancer and/or birth defects or other reproductive harm.
DO NOT PLACE SOLDER, ELECTRICAL/ELECTRONIC OR PLASTIC COMPONENTS IN YOUR MOUTH FOR ANY REASON WHAT
SO EVER!
Avoid prolonged, unprotected contact between solder and your skin! When soldering, do not inhale solder fumes or expose
eyes to solder/flux vapor!
If you come in contact with solder or components located inside the enclosure of this product, wash your hands before handling
food.
Protective Circuit (poly switch)
All full-range loudspeakers are fitted with a self-resetting poly switch that protects
the high-frequency driver from damage caused by excessive power. If a
loudspeaker cabinet loses high-frequency output, immediately remove power from
the unit and wait for two to three minutes. This should be long enough to allow the
poly switch to reset. Reapply power and check the performance of the high-
frequency driver before continuing, with the power reduced to a level that does not
cause the poly switch to interrupt the signal. (On the subwoofers, the poly switch
protects the woofer and a similar routine should be followed if the output is lost.)