GP 40 can sound be added

[edbubie]

I just got a GP 40 loco and would like to have sound with it can this be done and ho hard is to add.

[richg]

I just got a GP 40 loco and would like to have sound with it can this be done and ho hard is to add.

It will be hard if no experience with adding DCC and sound. Probably the frame will have to be modified.  This question has been posted before.
Lowest cost sound decoder with speaker is about $50.00 The most expensive will be about $140.00. There are many differences between the lowest cost and highest cost.  This all depends on you source.

I would suggest searching the General forum and HO forum for gp40 sound to get a better answer. You can use a PC to get here, you can use the same PC to search the forums and you can save those links to Favorites for future use. It will pay off.

Rich

[Tom M.]

I have done this for a couple of my DCC service customers.  I used a SoundTrax Tsunami AT-1000 decoder.  While intended as a board replacement decoder for Atlas diesels, it can be adapted for use in the Bachmann GP 40.  The biggest issue is milling the frame weight to make room for the speaker.  I milled the frame above the rear truck to make room for a 16mm by 35mm oval speaker and enclosure.  You have to totally strip the frame first.  Then you need to mill the frame either using a milling machine or band saw.  You can do it with a hack saw, but it it really difficult to do that way unless you can securely clamp the weight in a vice.  You also have to be careful not to disturb the portion of the frame/weight where the rear truck attaches. 

Tom

[richg]

Just in case the OP does not have the loco digram, the below link should be the one for the GP40.

http://www.bachmanntrains.com/home-usa/dwg/dwgs/H635X_IS005.pdf

Possibly it might be done with a belt sander but whatever is used, he will have to be careful. I have done some other brands of diesels with a belt sander and later with a four inch diameter rotary bench sander I bought off of ebay a few years ago. Got to keep some cold water nearby as the frame gets quite hot.

Rich

[richg]

I have done this for a couple of my DCC service customers.  I used a SoundTrax Tsunami AT-1000 decoder.  While intended as a board replacement decoder for Atlas diesels, it can be adapted for use in the Bachmann GP 40.  The biggest issue is milling the frame weight to make room for the speaker.  I milled the frame above the rear truck to make room for a 16mm by 35mm oval speaker and enclosure.  You have to totally strip the frame first.  Then you need to mill the frame either using a milling machine or band saw.  You can do it with a hack saw, but it it really difficult to do that way unless you can securely clamp the weight in a vice.  You also have to be careful not to disturb the portion of the frame/weight where the rear truck attaches. 

Tom

Below is what is suggested by SoundTraxx.

EMD GP40    TSU-AT1000 EMD 645 Turbo   828041   810113

The speaker suggested is 16mm x 35 mm which I have used also. No idea about the baffle though. A photo would be nice for the OP.
SoundTraxx has a suitable baffle but do not know what size it is.
Litchfield Station would be very helpful if you email them unless someone here gives details.
I did the Spectrum 44 ton and 70 ton with the same speaker but made my own baffles out of sheet styrene which I can post if interested.

Rich

[bapguy]

Pull off the fuel tank and see if there is space for a small speaker there. There might be a small square or rectangle hole there that could be milled out

[richg]

Pull off the fuel tank and see if there is space for a small speaker there. There might be a small square or rectangle hole there that could be milled out

If you go the route, make a fine mesh grill for the speaker opening. You will be surprised at how much magnetic material can be picked up by the speaker magnet.

Rich

[bapguy]

I should have stated that if a speaker will fit in the hole under the fule tank be sure and replace the fuel tank cover. I agree with the magnet attrackting metal. Joe

[Doneldon]

edbu-

A piece of a woman's stocking stretched over the speaker grill will catch most debris.

                                                                                                                     -- D