A question about how you set up your DCC speakers. With the traditional hifi stereo speakers we are all familiar with the cone faced forward and the enclosure was behind the speaker, do you set up you DCC speakers in the same manor? Or do you put the enclosure in front of the cone side of the speaker?
I seem to find conflicting info.
If you are wanting your sound to exit out a fan grill do you also try to have the sound from the back side of the speaker exit also or not worry about it? The more I read the more confused I seem to get.
With a typical cone-type speaker, it really doesn't matter whether it's facing in or out. That aspect boils down to the available room.
Given two identical eclosures, with the cone facing out, the bulk of the speaker is inside the enclosure. This makes the overall physical size as small as possible (good) but the speaker itself reduces the actual volume of the enclosure (not good). With the cone facing in, there is more air volume in the enclosure (good) but with the physical bulk of the speaker itself outside the enclosure, it's overall physical size is bigger (not good - unless you have the room in your engine), which would be the best set-up.
Even more important to me is your comment about "letting the sound out" of the shell. In all honesty, that's NOT what you want. With the speaker directly behind any grill opening, it becomes immediately obvious, that single location is where ALL the sound is coming from - engine / bell / horn / etc.. If the horn is on the front of the engine and the speaker is behind a rear fan grill, the horn sound is coming from some place different than the horn actually is.
By sealing ALL the external openings in the shell, you have essentially created another enclosure (albeit a poor one) for the speaker to resonate in. By having the sound resonate within the shell, the sound waves fill the shell and eliminate that "pin point sound source". If anywhere, the sound escapes the shell downward through the trucks, further dispersing the sound.
Myself, I use the tiny sugar cube speakers and place one at both ends inside a sealed shell. Very hard to tell exactly where the sound is coming from within the shell.
Mark.
¡ uʍop ǝpısdn sı ǝɹnʇɐuƃıs ʎɯ 'dlǝɥ
Thanks Mark, what you say makes a lot more sense. However I had read the comparison of a speaker in a shell with no outlet for the sound is like putting your stereo speaker in a cupboard.
so, if your intention is for the sound to solely exit out around the trucks do you aim the speakers downward? Does it matter which way the speakers face at all inside the shell? I have always tried to face the speakers towards the exit, in older loco installs this has proved difficult at times.
Mentioning sugar cube speakers, am I right in thinking these do not have a cone like a tradional speaker? I tried installing one and could not get it to work at all.
My last sound install I was very disappointed with how my Wow sound decoder sounded, I thought it was to do with its enclosure. I do know what you are saying about that pinpoint sound coming from a grill not resulting in a good effect. Thanks.
With sugar cubes / micros be sure to use an enclosure box. Typically a separate box with the membrane on one side. In tight space like an HO RS-2, I used the roof as one side, plus styrene walls and the speaker.
You will find differing advice on whether the membrane (looks like foil or ceramic) should face in or out. Tony's recommends facing in as distortion they say is lower. Larry Hanlon at LokSound yahoo user group shows data demonstrating better lower frequency capability with membrane facing out. Perhaps both are true and it is a choice between marginal distortion and marginal lower freq capability.
In my HO diesels I typically make styrene boxes placed so sound exits primarily thru truck openings. Note that marginal speaker enclosure size has a significant effect on lower frequency capability. A 9cc enclosure sounds much better than a 3mm, for instance.
Paul
Modeling HO with a transition era UP bent
Hi basementdweller,
I use the sugar cube speakers now exclusively. They sound great and it is easy to find space for them.
There are a couple of great articles on sugar cube speakers here:
http://www.sbs4dcc.com/tutorialstipstricks/sugarcubespeakernotes.html
http://www.sbs4dcc.com/tutorialstipstricks/wiringmultispeakers.html
I build my own enclosures out of .040" styrene. (Note that you must have an enclosure! The sugar cube speakers sound horrible without them.) It is important that they be air tight.
As Mark says, you can install more than one sugar cube speaker in most engines, but before you do that, read the links above to understand how various wiring methods affect speaker impedance. If you are using multiple speakers your decoder has to be able to handle the impedance of the speaker system, not necessarily that of the individual speakers.
This little guy has two sugar cube speakers installed in it:
Dave
I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!
I really appreciate all the info, photos and links. Thanks everyone. I will keep you informed of the progress.
Just a follow up, i completely re-thought this sound instalation. I was able to make an enclosure out of a plastic plumbing fitting and then aimed it down through the rear truck. Relocated the decoder and keep alive to accomplish this. It sounds much better than the way i had it.
This was in an old Lifelike P2K PA-1.
Thanks for all the replies.