DCC sound unit in #82305 Baldwin 4-6-0

[Bent-Spike]

I have a Digitrax sound module i have attempted to install in this engine, but keep  having problems.  The functions work porperly, but the sound is extrememly weak.  I have attempted to do research on baffling and have made one that allows me to install the speaker in the upper compartment of the tender, after having drilled many small holes to accomodate the sound output.  Anyone have any suggestions on increasing sound level.  Checked with Digitrax and they are saying I am installing it properly. . . Any help would be appreciated.

[Jim Banner]

You might be better off joining the Digitrax group at Yahoo! and asking the question there.  From what you have said, it sounds more like a decoder problem than an locomotive problem.

The baffle you use can make a huge amount of difference in the sound output.  The baffle MUST be sealled to prevent any sound from escaping from the back of the speaker or it will cancel the sound from the front of the speaker.  The larger the baffle, the less energy the speaker expends compressing and decompressing the air inside the baffle and the more energy it can radiate as sound.  And generally, the lower the impedance of the speaker, the more sound it will put out but DO NOT use a lower impedance than the lowest recommended by the manufacturer of the sound system.  A higher efficiency speaker will put out more sound than a lower efficiency one but miniature speakers are rarely rated in terms of efficiency.  If the worst comes to the worst, you can add a booster amplifier, but you will probably have to build your own to get one small enough.

Jim

[richg]

Some mount the speaker just under the coal load, BUT, the front of the speakers has to be completely isolated from the front. They drill tiny holes in the coal load. Myself and another fellow have mounted the speaker like that but the rear of the speaker faces up. The tender portion under the speaker is the baffle and the front of the speaker fires down.
Some leave the coal load intact and drill a series of holes in the tender frame just below the speaker cone. The speaker front points down and sealed from the rear of the speaker. A thin ridge of bath caulk around the solid rim of the speaker front but no caulk on the speaker cone.
Bottom line, always isolate the front and rear of the speaker.
Below is a good site to learn a lot about sound decoders even if you use a brand other than SoundTraxx. Look in the Curriculum link. Take you time. DCC sound is not plug and play. Store the link in Favorites.
He also has some examples of installs.

http://www.mrdccu.com/

Rich