What speaker is going to work well in an Athearn SD40-2? Do I need to obtain/fabricate a baffle for it, or could it be installed in one of the roof fans (effectively using the entire shell as the baffle)?
I used 4. 1 oval + 1 round + 2 round. That covered all 5 fan vents. The effective resistence was 8 Ohms (2 parallel sets of 8 ohms wired in series)
Don - Specializing in layout DC->DCC conversions
Modeling C&O transition era and steel industries There's Nothing Like Big Steam!
What brand or model of speakers?
So..............how did it work?
I would have to measure them to be sure the sizes. But the rounds were high-bass.
The high bass plus the oval are available at tonys trains. However a number of vendors now sell them. I custom cut 3m double sided foam tape to serve as a gasket. It was no louder then a conventional setup but the bass was a little better and the horn wasn't distorted at max volume.
The wiring went like this:
Speaker set 1:
red wire from + speaker terminal decoder to + terminal on oval speaker 1
Black wire from - terminal oval speaker to + terminal round speaker 2
Black wire from - terminal speaker 2 to - speaker terminal on decoder.
Speaker set 2:
red wire from + speaker terminal decoder to + terminal round speaker 3
Black wire from - terminal speaker 3 to + terminal round speaker 4
Black wire from - terminal speaker 4 to - speaker terminal decoder.
When you are done, you will have two red wires on the decoder's speaker + terminal, and two black wires on the decoders - speaker terminal.
This is the brand of speakers I use: Railmaster Hobbies. I have done several SD-40T-2 and GP-40's. I use the Bass Reflex Speaker -narrow, 8 Ohm for the SD units. It is a really good speaker and fits in the shell very well. It does take a little bit of sanding on the sides to make it fit but it is well worth it. Also it has two mounting lugs on each end. I usually just cut them off. I have used this particular speaker in 5 SD-40T-2 Installs.
The SD-40T-2 is slightly bigger than a SD-40-2 so you may want to use a DS1436-8 instead. It is a slightly smaller speaker enclosure but still gives you a good level of sound. I use this speaker in my GP-40's which have less space than the SD-40's.
Both of these speakers come with prefabricated baffles. The bass reflex speaker-narrow is very close to the inside dimension of the Athearn shell. A few swipes across the side with some sand paper makes a perfect friction fit in the shell (no glue needed!)
I have installed both types in Athearn and Atlas Models and have been very pleased with them.
Also I am not affliated with them in any way. I am just a satisfied customer!
I hope this helps.
Colorado Front Range Railroad: http://www.coloradofrontrangerr.com/
If I can give a more "generic" answer...in a narrow-hood diesel like a GP, SD, RS etc. type, generally a 1/2" x 1" speaker is the largest that will fit in the body. (Some engines have a pre-built speaker enclosure in the fuel tank between the trucks that can hold a 1" round speaker - I wish they all did!) E, F or FA/PA engines generally will hold a 1" round speaker with ease.
In a tight squeeze, you can get by without an enclosure. That generally works better in a steam loco tender, where the shell is "air tight". In a diesel, if you put a speaker in the body facing up so the sound comes up through the radiators, it's possible some of the sound will escape by going down through the openings around the trucks. Depending on the model, this may or may not be all that noticeable.
Several companies offer speakers either already in enclosures, or with 'snap fit' separate enclosures. As much as possible, I like to buy speakers now that come with wiring already attached, for me soldering wires to the small pads on the speaker can be a little trying, though eventually I get it done.
Have you looked into the "sugar cube" speakerss? They are small and selfcontained (come with an enclosure)> I have not heard any personally except via u-tube videos, but they're suposed to sound reallt goood amd have good volume.
Jay
C-415 Build: https://imageshack.com/a/tShC/1
Other builds: https://imageshack.com/my/albums
Are the ported speaker baffles sold by Digitrax any good?
A port in an enclosure the size we are using in our models isn't even feasable. These little speakers cannot move a sufficient volume of air within the enclosure to even make a port function ! All a port this small is going to accomplish is reduce the any effect backpressure that may exist within the enclosure and weaken the speaker's effectiveness.
Ports do not function unless there is enough air pressure within the enclosure to utilize one. Even then, the port has to be carefully tuned - the size of the opening and the length of the tube. Even in home stereo speakers, an inproperly tuned port can actually make the sound worse instead of better - but this is utilizing 10 to 15 inch speakers that can actually move some air !
Mark.
¡ uʍop ǝpısdn sı ǝɹnʇɐuƃıs ʎɯ 'dlǝɥ
Made the link clickable for Don's video:
https://www.youtube.com/watch?v=UGb4JMct7Tk&feature=youtube_gdata_player
Dave
I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!
Holy CARP those sound great! I'm going to have to revise my opinion on "onboard sound has no bass!"
Disclaimer: This post may contain humor, sarcasm, and/or flatulence.
Michael Mornard
Bringing the North Woods to South Dakota!
In the video, 20mm speakers are installed in a Kato SD40-2. Would these also fit in an Athearn SD40-2 or are the shell dimensions different? (the closest measurement I could make is about 19mm, but it's tough to get in there with the calipers to measure the inside shell precisely)