A Better Speaker for 5v PS2 ?

gunrunnerjohn posted:

Using an 8 ohm speaker and a resistor will work, but you'll be expending half the energy in the resistor.  Hard to imagine that'll end up being "better".  Find a quality 16 ohm speaker if you want a replacement.

 

One solution if you can fit it in is to use two 8 ohm speakers in series, that will usually give you better sound.  Another useful move is to simply put a proper baffle on the existing speaker, you'd be amazed how much improvement that will make.

 

 John, I was wondering if you could explain what a  "proper baffle" is? 

Thank you.

One that fits in the space you have and is sealed or mostly sealed around one side of the speaker.

A good baffle compresses the air on the back side of the speaker in order to tame the movement of the speaker and limit it to only the movement that's intended. Kind of like putting shocks on a car. Without them the car will keep bouncing several time from only one dip in the road. Same with a speaker, without a good baffle, the speaker will bounce more then what was intended. If you can find a small spray can lid or find the part number for the baffles MTH once used, and sealed it good over the speaker, you'll notice a much better sound quality. 

Thanks for the response...just to clarify  you  guys have successfully improved the sound quality of a PS2 engine?  Many of the sound sets in PS2 are interesting but have a lot of treble....many newer PS3  engines have very rich, clear robust sound...the fidelity  is greatly improved...

Dave Zucal posted:

A good baffle compresses the air on the back side of the speaker in order to tame the movement of the speaker and limit it to only the movement that's intended. Kind of like putting shocks on a car. Without them the car will keep bouncing several time from only one dip in the road. Same with a speaker, without a good baffle, the speaker will bounce more then what was intended. If you can find a small spray can lid or find the part number for the baffles MTH once used, and sealed it good over the speaker, you'll notice a much better sound quality. 

While its true the baffle will act as an air spring for those drivers that require it, the primary reason for the baffle is it blocks the back wave from canceling out the air pressure of the front wave. When the cone is moving forward it creates pressure at the front but also a vacuum at the back. At low frequencies the air has time to move from the front to the back effectively reducing the air pressure traveling to the listener.

The 25 cent drivers MTH and most other train manufacturers used up to the early '90s were already very stiff and as a result had very little excursion at low frequencies. Using the car comparison it was like having 1 ton pickup springs on a sedan. OTOH if you wanted to add load capacity to your sedan then adjustable air shocks could benefit. Speakers designed for closed box designs have weak springs to begin with and will sound muddy when the air spring is insufficient or missing altogether.

Not a lot of choice in small 16 ohm speakers. Most of the alternatives are too tall to fit on our engines. Best stick with GGG's suggestion of the later MTH speaker. If you had a very large tender like a NYC PT or Santa Fe Northern you could use two 8 ohm speakers but not too many other places this will work.

Pete

gladstone23 posted:

Thanks for the response...just to clarify  you  guys have successfully improved the sound quality of a PS2 engine?  Many of the sound sets in PS2 are interesting but have a lot of treble....many newer PS3  engines have very rich, clear robust sound...the fidelity  is greatly improved...

Yes, a proper baffle will do wonders for the sound quality.  Not only improved volume, but also improved bass response.  I add them whenever I can.

In the real scheme of things, an audio engineer will actually compute the proper size for the baffle and match it exactly to the speaker, however, almost any baffle will do wonders for the sound, even if not the optimum size and shape.  If you want to see examples of some fairly fancy sound engineering, take some higher end laptop computers apart.  They get amazing sound with very small speakers and enclosures.  You'll also fine that some of the enclosures are actually ported with tuned ducts to improve the sound. 

FWIW, this type of engineering is above my pay grade, but I can stick a spray can lid on a speaker and greatly improve the sound.

I have a friend who demands stereo quality from his trains.   I have been in many train stations in my life and always considered myself lucky if the announcements could be understood.  The best are the onboard Acela (real one) .  Others not so good.   I remember a few years ago waiting for the northbound Acela at BWI.   When the station person made the announcement that the Acela was due, everyone on the platform looked at each other and asked what was just said.  Very sad.

I have been impressed with the integrated speaker and baffle units that comes with The ERR railsound boards (shown below). They put out quite a bit of volume given their relatively diminutive  size.   I was able to squeeze one and its board into a Lionel switcher slope backed tender which I had mated to a K Line Porter.

As the directions that come with the ERR kit state, your get the best results when you install the speaker and baffle unit facing down towards the track.  The biggest challenge I had when installing things in the slope backed tender was cutting the opening for the downward facing speaker.  Due to the shape of the tender shell, the only place the baffle would fit was at the very front of the shell, right over the front truck.  I used a dremel drill to  create a "swiss cheese" pattern of openings all around where that truck was attached, leaving just enough metal to retain structiural integrity while maximize the openings for the speaker. 

A small section of PVC pipe hot glued on the speaker will do better than that.

I redid the central vacuum at my old house and ended up with a bunch of 2" thinwall PVC, perfect for making baffles.  I just glue a lid on them for the total seal and they work very well.  You can cut the pipe to whatever length will fit over the speaker and clear the shell.  I find that usually making it as long as you can is best.

Upgrading a mediocre/old speaker and adding a baffle can provide the extra punch to a engines sound system which many of us are looking for.  Can we summarize a listing of  good 2" high efficiency replacement speaker for the various ohm requirements.  GRJ- I know a while back you did some testing of speakers, what was you final results?  

4 ohm - 

8 ohm- 

16 ohm - MTH BF-0000033 16 ohm 5W speaker.

Thanks,

Bob D

I don't have anything documented Bob, but others like Doug (laidoffsick) have done more extensive testing and I believe documented it here.