The Digitrax sound decoders (which require the add-on lighting attachment) that are designed as drop-ins for Kato AC4400, SD-38 and F40PH engines come with a 1" round speaker. Those engines all have openings in the fuel tank for the speaker.
Soundtraxx made sound decoders for some Spectrum steam engines that had a speaker built into the board, but I don't think they've made them for a few years(??)
MRC makes some light-board replacement decoders that have a 1/2" decoder built into the board, to use in narrow body diesels like Atlas RS-1's etc.
Loksound comes with a speaker. QSI revolution sometimes come with a speaker. Some older Soundtraxx decoders came with a speaker on the board and in the package. I will not comment on MRC decoders.
Pete
I pray every day I break even, Cause I can really use the money!
I started with nothing and still have most of it left!
The Digitrax SoundBug (sound only) decoder comes with a 1-inch round speaker. I'm pretty sure the SFX0416, another sound-only decoder, also comes with a 1-inch.
Unfortunately, a 1-inch round speaker isn't always going to fit inside your engine. You can put them into F7s, because they are full-width, or into steam tenders, but Geeps and switchers where most of the shell is not full-width will require an oval speaker.
Most manufacturers understand that speaker selection is going to depend on the engine the decoder is going in. Digitrax is basically selling you a speaker that you probably won't be able to use, and not offering you a choice in the matter.
It takes an iron man to play with a toy iron horse.
I think I've seen HO full function decoders (motion and sound) that come with a speaker. Also, sound only that also come with a speaker. Anyone willing to provide a short list of same? A link to a web site would work as well, IF, the site makes the information clear.
I'm asking because I've yet to find a site that directly answers this specific question.
Thanks