Hi all, I'm want to continue with fitting sound to my locos, the next one to do is a Bachmann 45xx Priarie but I haven't been able to find a fitting guide online. I've checked the sites like Youchoos and Bromsgrove etc and done a general search on google but so far no joy. I was hoping someone who has done this conversion can give me some info on how they achieved it.

Colin

Hi Coline Have you seen YMRC DCC Forums and Forums Jump.

Should be on Google Bachmann loco decoder &C.Vs.

Hope  this is of help, writing on tab bit limited on use.

Enjoy Forums

Best of Luck

Dave D.

I've just had a google and find that some had a socket and some didn't. I'd actually prefer no socket as I nearly always hardwire. A zimo MX648 is a small and very good sound decoder and there is a new one out that's smaller again.

I haven't done this particular Loco' but have put in quite a few. I find that a Zimo or CT sugar cube speaker will fit most models, and if not you can cut down the enclosure, which I've done more than once.

The sugar cube speakers can usually be hidden in a smoke box or the bunker.

I think your best bet is to take off the body and check it all over.

Must go, battery running out.

Hi Colin,

I've done a DCC unfriendly installation (DCC socket but no room for a decoder), and the TCS website has a Bachmann 45xx installation - http://www.tcsdcc.com/Customer_Content/Installation_Pictures/HO_Scale/HO_Search/search.html - which is a hardwire. I'll dig the beast out of storage tomorrow and have a look to see what I did.

From memory I binned the existing board, hard-wired an 8-socket wiring harness, and then installed a small decoder. No sound, although a smallish sugar cube should fit in the boiler, or a regular speaker in the cab.

Nigel

Hi Colin,

Found it. Looks like I did a fair amount of work to this one. Bachmann wiring removed, board screw pegs filed off. Digitrax SDH164 sound decoder with GWR 57xx sound files (public domain) loaded. Must have been short of the readies at the time. Decoder is in the cab/bunker. One speaker on the roof of the cab, facing down, second speaker in the smoke box also facing down. Stay-alive underneath the decoder in the bunker. Cab interior spectacle plate removed to make life easier. You can't see the back-head anyway, so no loss.

Hole and slot drilled through the bottom of the smoke box to allow sound out. Slot is not visible from the outside. Acoustic foam used to ensure no sound leakage. Standard Digitrax 9 pin connector hard wired to pick-ups and motor. Enables a decoder swap with no soldering. Driver George and Fireman Fred at the windows would mask the work in the cab.

There are some options with this model. A small N-scale decoder or one of those direct plug decoders will fit in the space occupied by the board/pegs, or the solid bunker weights can be milled out and the decoder put in there. The speaker in the cab could be on the floor facing down (suitable holes drilled in the bottom) with the decoder sitting on top. I've used this approach with the Bachmann 56xx. I think I'll do that on this one as well.

The body unclips in this model, 2 catches bunker ends, the stays at the front from the bottom of the smoke box to the front plate need to be detached as well. May need an artists pallet knife and a bit of persuasion to get the body off. This sort of modification will of course void any warranty.

Bottom line - it's possible to get a full-sized HO/OO decoder, 2 speakers and a stay-alive in this model without too much difficulty.

Nigel

 Photo 1. Decoder in cab, resting on stay-alive in bunker. Kept in place with DS foam tape (3M).




Photo 2. Speaker on cab roof underside, held in place with DS tape. Holes in underneath of bunker are to allow sound out. Real coal on top. Note butchery when internal cab spectacle plate was removed.
 



Photo 3. Speaker in smoke box. Hole and slot drilled/cut to allow sound out. Smoke box plugged with acoustic foam (bottom of photo, just visible).

Well done Nigel.  Must have been quite a challenge.:shock:

Hi Reg,

Thanks. Probably the first sound installation I did, threw everything at it. Bet there's a kitchen sink in there somewhere. I'd do it differently now. Picked up the model for less than 50% retail, so no qualms about butchery, holes etc. Issue I'm looking at now is conversion to EM gauge. £87.60 for the wheelset. And I have 2 of them. Hmm. 

Hope Colin finds it useful as it's a straightforward conversion.

Nigel

Thank you very much Nigel, it's given me some pointers, tomorrow I'm going to strip it down, measure any cavities available and put my thinking hat on. I've found some info on Youchoos saying a Sugar Cube will go in the boiler but I remember having to source a very slim decoder to go in there when I changed it to DCC. I'll post how I get on when/if it's done.

Colin

Hi Colin,

I would imagine nearly all N-scale/minidecoders would fit in the boiler/smoke box space. For that matter, an N-scale one should fit in the bunker. If you used a 6-pin connector or hard-wired it that would keep space requirements down as well. Which would leave plenty of space in the bunker for the speaker (you can see where I'm going). 

Nigel

Hi all, I've just sound fitted the Bachmann Prairie, much easier job than I feared. I fitted a Locsound micro V4 with a 16x25 speaker including the baffle box. I cut the rear cab inner wall up to the bunker shelf, painted the back of the speaker baffle Matt black and stuck the complete speaker assembly facing down on to the bunker shelf. I drilled a series of holes through the metal weight/body frame under the bunker for the sound to come out before I reassembled the body to it. There's enough room to leave the brake and regulator in situ. I slipped the decoder up the boiler tube making sure most of the wires were also tucked up inside the boiler tube, the speaker wires had to be extended by a couple of inches so I could stick them around the body sides from the bunker. Can't see the speaker in the cab and there's still room for crew without cutting off there legs. It sounds great.

Colin

Hi Colin,

Well done, glad it was not complicated. One thing I did on the Class 56xx which has the speaker and decoder in the cab/bunker was to connect the speaker to the decoder with 2-prong miniature plugs/sockets and leads. That way the decoder can be removed without pulling the whole lot out (speaker on the bottom, fixed, decoder sitting on top).

Nigel