Second part of the service manual for the Audio Pro A4-14 speaker, going by the spk and sm2 tokens. At 12.8 MB it is a large, likely scanned document that should be read with its companion first part. Expect circuit diagrams, crossover or amplifier details, exploded views and parts lists, though exact contents depend on the scan. Use it to trace signal paths, identify components and order spares. Check your unit's model label and any board markings against the drawings before relying on specific component values.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @pdf_servicemanual. Enginerys does not host this file.
How to open a .pdf file
The standard format for schematics, block diagrams, power-sequence charts and service manuals.