I saw this new Drop-In Sound Announcement for E, F and PA locos from Soundtraxx. I think that this is noteworthy as Drop-In sound is a big-deal for N-Scale. The kit includes Tsunami2 decoder board, speaker with baffle, LEDs wire and tape. The application note says that it takes 1-hour to do the installation. - Tonkphilip
For E8’s, decoder fits but not the speaker with any of the provided baffles. Waiting for a response from them before I hack into the chassis.
here is the link https://soundtraxx.com/tsu-kn1/ Also on TrainBoard advertiser Streamlined Backshop https://store.sbs4dcc.com/Soundtraxx885032TSU-KN1Tsunami2DCCSoundDecoder-KatoE/F/PA/F40/P42.aspx the speaker that comes with the decoder is a 12mm x 5mm speaker. Even with baffle, it has very mediocre to poor performance under 1000 Hz, so it will sound tinny.
Soundtraxx now has a YouTube video (Soundraxx site/reference/videos/youtube), showing the installation and sounds in a Kato F3. I think the plugNplay factor with just two wires to solder for the speaker, is a good step for N-Gauge sound! Agreed, a bigger speaker could be added by sawing away the metal inside the fuel tank. - tonkphilip