What is the best speaker to use in locos?

I don't think it's the speaker as much as it is the speaker enclosure. I've had good luck with ERR products.

Regards

Romiller

If frequency reproduction specifications for train size speakers are even available I figure that would be the jumping off place. Since tiny speakers are so low frequency deficient, next would be devising an enclosure/baffle to emphasize what lows there are. An externally programmable 15-band eq on a chip would help considerably as well.

Pete

Pete,
I was just about to advise Dave to google DCC as there are several articles on speaker baffles at most of the DCC sites .I'm gonna tell you the same thing concerning your graphic equalizer.
The Tsunami TSU-750 has a built in 16 band graphic equalizer coarse it's DCC so you can only wish

David

The Williams units have worked well for me in locomotives they'll fit into.  The ERR units are OK, but they're smaller than the Williams speakers I have.  Both have a similar baffle on the back, that's pretty necessary for good sound.

The best 8 ohm speakers I have used were the Digital Dynamics Megabass units. Not available from them anymore but perhaps someone here knows where Ed got them from.

Lionel offers their FatBoy and mini Fat Boy speakers in 8 and 16 ohm versions. They work well also. I think the ERR offers the mini Fatboy (40mm) with their Railsounds. The Fatboy is a 50 mm speaker. I'll defer to others on 4 ohm speakers used in some MTH engines. The OEM versions are not too impressive but there are quality replacements available.

BTW the "best" speaker for your application will depend some on what sound system you have. You won't extract optimum results with a 1 watt amplifier. Legacy amps are 5 watt.

Pete

The Williams ones I have are the 50mm ones, that's why they're a bit large for some locomotives.  They have what looks to be an identical enclosure to the ERR ones, just larger.

Does anyone where to get seperate sale baffles?  Thanks!

I take the tops of spray cans and cut them down, they make nice baffles.  No reason to buy a piece of plastic.

The Lionel Fat Boys if they will work with your sound system. They really sound great. You can buy them from Lionel.

Pricey but excellent quality. They have 2 inch, 4 and 8 ohm

http://www.madisound.com/

The 2 inch page

http://www.madisoundspeakersto.../approx-2-fullrange/

Here is some information on installing,at least the way I do it

http://www.jcstudiosinc.com/BlogShowThread?id=621&categoryId=426

If they fit I use 1 or 2 of these. Nothing else I have seen comes close in performance

http://www.madisoundspeakersto...-2-full-range-4-ohm/

Digital Dynamics is going out of business from what I hear.

Dale H

A really simple baffle is a 2" white PVC cap used for vacuflo systems, and a short section of 2" vacuflo pipe. It nicely fits the back of most 50 mm speakers and can be attached using RTV or similar glue. Cheap and simple.

Rod

Sound is very good but it may be a bit of a tight fit on some smaller engines:

For those with a technical bent here are some links that will let you test a given driver for its parameters which determine the optimum enclosure size. It would require some electronic instrumentation:

http://sound.westhost.com/tsp.htm

Now having that information you can input the values into this enclosure calculator for a closed box.

Fortunately the links the Dale provided above give the parameters for their drivers so you can apply them in the link below.

http://www.ajdesigner.com/speaker/asealedexample.php

I have tested a few of the more common drivers including the DD MegaBass, Williams, and the early flat driver the ERR offered with its Sound Commander. I determined from their parameters that even the smallest of them would require an enclosure the size of a modern high cube boxcar for optimum bass. When you seal the speaker with anything smaller like paint can top you get a large peak in the upper bass but lose all the lower bass that the driver is capable of. It gives the impression you improved the bass but you actually are losing more than you gained.

Google "thiele-small" and you will get links that show the effects of changing the box size for a given driver. The second link above will let you change the box volume and show the resultant frequency response

Pete

I just did some calculations using the speaker parameters for the Peerless 830970 that DaleH recommended. Surprising to me that the ideal enclosure is actually smaller than the spray can top, perhaps less than half that volume.

Here are the results when using the volume of a spray can top:

For comparison here the results using an enclosure for optimum response, that is flat with no peaks:

Notice the Vb (box volume) in the right column is less than half the value of the volume of a paint can top. Given that the speaker itself takes up much of the volume a paint can top might actually return optimum bandwidth. 

To change the results the value for Qtc was changed. The other values were given for the Peerless driver and simply plugged into calculator program. Optimum Qtc is .7. The smaller Qtc was entered by trial and error until the volume of the paint can top was achieved.

Pete

Well, I cut the can top down so it just fits, so maybe I stumbled into the "ideal" size and didn't know it!

I wonder if changing the speakers in the ERR Railsounds units would improve the sound, and not have so much static!!!

John, Of course different drivers will have different optimum enclosure sizes but I would guess now most would be fine with a paint can top.

Mark, changing the speaker might reduce the noise but at the expense of the higher frequencies sounds. The best way to deal with noise is improve the sound boards. Without looking at the signal from the sound boards it would be hard to tell if its generated in the sound chip or power amp board.

Pete

Pete

Good information and research. Thank you

Dale H

Dale and Pete, thanks, good info.

Well,  I get "baffled" by all the different types of speakers.

One of the links shows these:

Tweeters

Woofers

Fullrange

Midrange

Subwoofers

Auto Sound

Bass Shakers

Not being an audiophile I don't know one from the other.  I'm guessing that "full range" speakers are the ones we should use?

Is there a speaker primer that would help understand them better?

Should we ask the admins to move this to the ELECTRONICS sub-forum?

Bob, yes full range are what we are looking for. Given the very small space there is to work with, separate drivers for bass, midrange, and highs would not fit.

Try this link for some good information on loudspeakers. Checkout the Concepts link on the left column.

http://www.linkwitzlab.com/index.html

Pete

Thanks Pete!

I just Googled "Model train Speakers" and found MB Klein (Model Train Stuff) has some for sale:

http://www.modeltrainstuff.com/Speakers-s/1171.htm

I'll look at the link you posted as well as what Google brought up.

Here's a primer I found on the SoundTraxx site:

http://www.soundtraxx.com/primer/

Looks like an excellent primer Bob and aimed at model railroaders.

I noticed the images for the box calculator above are a bit fuzzy.

For clearer images you can click on these links:

Spray Can Top Baffle:

http://www.majhost.com/gallery...ar/speaker_paint.jpg

Optimum Enclosure:

http://www.majhost.com/gallery.../speaker_optimum.jpg

Here is a link to download the software. Its an .exe file so MAC users will need way to run Windows software.

http://www.ajdesigner.com/speaker/index.php

The particular program most applicable here is the Sealed Box program. The Vented Box software could be used if you have a boxcar or similar to mount the speaker in.

http://www.ajdesigner.com/speaker/index.php

Pete

I have to say that I avoided this thread because I expected the usual answers. 

Was I WRONG. 

The speakers listed are phenomenal.  I've looked for some quality speakers like that and didn't find them.  The magnets on those should allow for some great bass. Thanks Dale H!

 I've used DD speakers and was happy, but the RS5 and later speakers from Lionel are better and not that expensive.  They have much better magnets and what I think are polypropylene cones.

The baffle info is especially helpful.  Thanks Dale and Pete!

Dale H - Your installation looks superb.  Could you comment on a comparison with OEM installations?

I came to O scale from N scale . When I started using DCC I started putting DCC and sound decoders in my engines . It's a little bit of a chore but after a while you get good at trying to fit a 1/2 inch diameter speaker and the decoder in the tender.

In N scale to get any real sound out you have to drill tiny holes in the coal pile and mount your speaker pointing up.Because of the rough surface of the coal pile you really can't see the holes. The tender can act as a baffle or a baffle can be fashioned from a plastic thimble or small bottle cap.

I did try this with some MRC sounders I bought to try to get more sound out of them.
My first experiment was on my Beep . I mounted MRC's speaker in the cab pointing up
but found out that because of the ERR TMCC board underneath it a paint can top wouldn't fit .So looking around I found of all things a ping pong ball . I cut it in half and it fit perfectly.
Now I don't know if it's the round shape in the back verses the square shape of the can top but it did have noticeably a lot more sound. It just didn't have enough sound to compete with my Command equipped engines so I ended up installing an ERR sound board. The speaker for the ERR board wouldn't work with the ping pong ball because it's larger so I had to do away with the baffle.

So if you have the room use a baffle . If you have those MRC sounders try the ping pong ball might get you a little more sound.

David

For a steam engine you want a speaker with good low frequency response, a lot of cone area to reproduce those sounds when the engine labors.  For an electric or diesel engine almost any small speaker will work.  No need for low frequency response.  Also keep in mind the correct impedance.

One option I was looking at was finding good 8-ohm speakers and using them in pairs -- wired in parallel for 3v Proto-2 engines (4 ohms) or wired in series for 5v Proto-2 (16 ohms) The catch is that you need the space and extra wiring. Works if you have a large tender in a steam locomotive or a dummy behind a diesel. My particular thought was this would work well for A-B/A-B-B-A cab unit consists.

Excellent thought Matt.  MY MTH tenders have room for 2 speakers.  I had not considered multiple unit diesels.

Thanks.

Years (decades) ago, my father (a hi-fi nut, who built his system from kits) told me about a speaker system called the "Sweet 16" which got phenominal sound from 16 inexpensive, smaller speakers in a single enclosure. The speakers were clustered according to range and wired in series/parallel combinations to achieve the correct impedence. Always thought that would be interesting to try, but for model locomotives in our chosen scale, a subset of that concept seemed viable.

For a 3v Proto-2 (4ohm) A-B-B-A, you could put a 4-ohm in each unit of an A-B pair wired in series, then connect this combination in parallel with another A-B pair to get back to 4 ohms, and you'd have sound radiating from all four units. I was looking at that for my FT A-B-B-A set.

One thing to consider Matt is while you can create the correct impedance for a given amplifier you won't increase the volume very much unless you increase the power. The power will just get divided up among the drivers if you don't use multiple amplifiers.

BTW the original Bose 901s consisted of 9 bass-midrange drivers in each box, 8 facing forward and one facing back. They were used with an equalizer to compensate for the fact that those drivers lacked deep bass or the extreme highs.

Pete

You could take apart a few laptops and use a bunch of these for your multi-speaker array.  They have surprising volume and sound reproduction for the size.

I use these

http://www.soundlabsgroup.com....isaton+Speakers.html

Lionel does a decent job on OEM in their expensive engines. 2 fat boys sound pretty good. Then sometimes they really cheap out. You have to remember Railsounds 2.5 ,4 etc is/was a stand alone sound system. Neil Young had an audio background to say the least. At least fidelity was a criteria in the original design. I have an F-3 B unit with Rs4 and it is pretty good. I disagree with the poster who says low end is not needed in a diesel. There is plenty of low end rumble in a real one.

Ed Bender of Digital Dynamics is a good engineer and understood reproduction. Too bad he was limited by what he was allowed to use from Lionel. 

The old OTT system even had decent baffling which made a difference. For it's day it was a good system

The MTH Proto 1 and 2,at least all the ones I have are really lacking. This is because it was designed as an operating system with sound as an afterthought. If you look at the speakers used,no serious audio engineer serious about replicating sound would use such an approach. In diesels,little room is left for a decent size speaker or even baffling. Above there is a bunch of junk to rattle around. In steam engine tenders,they have plenty of room but still opt for a cheap speaker. The only way I can interpret the design is that fidelity is not a high priority for them. This is just my opinion,not meant to bash MTH. I have a lot of their engines over 100 and am slowly getting around to changing all the speakers in them. I can say that changing the speaker can make a big difference. There is a lot of stuff in the sound chip that is not reproduced by the OEM speaker due to lack of range. In doing so we are trying to overcome poor initial design. Kind of like building a race car where the designer only left room for a lawn mower engine. Baffling,room allowing is also important,even if using the paint can lid. I use fish food containers sometimes.The specifications of the Peerless speaker is very imnpressive for one that size.

Audio engineering is an involved science and I am not an engineer. However the companies have engineers and I am sure can do some better engineering for what these things cost.. Perhaps cheap components are more important than good quality sound . The ultimate judges are the customers and their pocket books.

Dale H

Used to do discos with 8 of these driven with Phase Linear amps. Nothing quite like them but they had their critics for true sound reproduction. Had enough power to shake a building no kidding.

Dale H

I'm a bit of a neophyte with speaker installation and I'm trying to fit a PS-2 upgrade kit into a very small tender that has an 80hm/0.5W already installed. Can anyone tell me if connecting a 2" 8ohm/0.5W speaker to a PS-2 upgrade system (comes with a 4ohm/0.5w) is likely to cause damage?

Going up in impedance should not cause damage. You may get lower volume. Putting in less impedance than designed for could damage the amplifier. So replacing a 4 ohm with an 8 ohm is OK if you get good results with volume.

Dale H

 I put the speaker above that Dale recommended into a 3rd rail Allegheny with PS2. I'm very happy with the overall sound quality now. It is the size of the tender enclosure that makes the difference in extra bass response.

 Holly cow!

That is old? My first speakers bought (used!) back in the seventy's for sound reinforcement. Then, I went with JBL 4550s and their 2" long throw horns.