Double sound?

[rich19]

A question not specifically asked for On30...

Is it possible (from simple --> difficult) to have a sound decoder in the steam locomotive and a second (identical) sound decoder stationary located under the layou for the low frequencies?

Any synchronisation issues here?

Thanks for your help! Richard

[C.S.R.R. Manager]

I've actually thought about this, Rich.  The small speakers in locos just can't make good low-frequency sounds, but they handle mids OK and highs fine.  Also, it's hard for the human ear to tell which direction low-frequency sounds are coming from, while mids and highs are easier.  So there is some rationale to a split-sound system, with the small speaker in the loco, and a large woofer under the layout.

The real question is the source of the sound.  I can't figure out how to make the decoder in the loco send a sound signal to the woofer, but I've thought of using an MRC external sound system, where the transformer creates the sounds.  You would then split the signal, and send part through wires to a woofer under the layout.  The other signal would be sent to a low-frequency FM transmitter.  The tender of the loco could house a small FM radio, connected to a speaker, with an off-on switch.  I've seen these radios at $5 in some places, so you could outfit several locos cheaply. 

On the downside, it's a one-loco solution, OK for a display layout, but not for a large empire.  Then again, if you were to load the woofer with sound from several locos at once, it would be quite a noise.  And this would be an easy way to add sound to a DC loco like the Mogul.

[NelsOn-30]

Richard

Possible, Yes:
In music reproduction the ear/brain cannot determine the location of sound frequencies below 200 Hz. Thus the advent of the multi channel sub woofer. The higher frequencies and overtones provide the location information.

Doable, Possibly:
Two problems to be overcome are synchronization and multiple sources. To maintain sync communication would be required between the loco and the separate base speaker. I can think of too many possibly impractical ways to list that this might be done.

Feasible?
The trick is going to be to avoid creating new standards by piggybacking the woofer “instructions” on top of or in addition to an existing standard.
I visualize a two part Sound and DCC decoder system one in the locomotive (tender) and the other “tuned” to drive the sub woofer. A single amplified common sub woofer would work for most home size layouts. A set of complementary sounds would be generated by the sub woofer decoder as instructed and synchronized by the locomotive decoder. UHF as in remote controls or more signals in the rails can be used to send addressed instructions to the sub woofer decoder.

Why not an add-on for base only?

Scale earthquakes anyone?

[rich19]

well, my concept is one that deploys 2 identical dcc sound decoders:
- one in the locomotive for the directional mid and high frequency sounds, and
- one for the non-directional ones "under the table"

It is my guess that under the condition that you use two equal sound decoders set at the same address and with the same setting, the sound output should be equal. Or not?

Of course, the "under the table" sound output has to be filtererd from its hig freq sounds first....

Did anyone try this?

[450sel]

Of course, the "under the table" sound output has to be filtererd from its hig freq sounds first....

Did anyone try this?

I don't think that it would be a problem to do this, could be done in the same way as with the car audio systems with a seperate woofer...

Hang a nice subwoofer under your railroad table, connect the decoder and a pre-amp which filters the higher frequency sounds and let the neighbours enjoy !

[hminky]

You can't sync the chuff.

Harold

[450sel]

Are you sure ?
I can imagine that the chuff can't be synced when using a wheel cam...but isn't the chuff speed increased when you open the trottle ? So both decoders should react the same i.m.o.

[hminky]

You can't sync the chuff.

Harold

Tried it, you can't sync the chuff because the under table decoder isn't reacting to the same parameters. Diesel sound won't even sync.

Harold

[450sel]

Shame...it could be a nice addition to the layout..ah well, could have been an interesting project. But if you already tried it there's no need for me to re-invent the wheel...

Thanks Harold,

Ron