Throttle Up! has several manuals for their various sound units. All but one of these manuals are free when ordered with a sound unit. If ordering a manual with the sound unit, do that from the same page where you order the sound unit. From there, it will be free - but only if accompanied with a sound decoder order.

For DSD-150 and DSX Steam sound units, there is a two-manual set that includes the Owner's manual and Technical reference. These manuals have a gray cover. Although these manuals list all the motor and light function controls for the DSD-150, those CVs are irrelevant for DSX sound-only decoders.

For DSD-150 and DSX Diesel sound units, there is a three-manual set that includes the same two for the steam units, plus a Diesel addendum. The Diesel addendum has a white paper cover. This manual covers the CVs that are different from Steam sound CVs. So, for generic decoder CVs, such as speed steps, speed tables, addressing, etc., use the Steam manual set. For Diesel sound adjustments, use this manual. Again, the motor and light function control CVs are irrelevant for DSX sound-only decoders.

All other sound decoders (decoders other than DSD-150 and DSX) have the suffix LC, for Low Cost. These sound decoders have completely different manuals, both with yellow covers. The Owner's manual is the one that comes free when ordered with a sound decoder. The Technical reference manual is $8.00 regardless - since Throttle Up! charges us for them whether purchased with sound units or not, we must charge you for it. The Owner's manual has everything you need to install and program the sound decoder. The Technical Reference has the same information, but is organized by CV for easy reference.