bachmann class 108 sound

[status quo]

Where is the best place to put the speaker in the class 108? It is the round speaker. Your help would be appreciated.

[SRman]

Ideally it should go under the floor or perhaps protrude through it. However, as you have probably already seen, there is a circuit board in the way, running the entire length of the coach under the seats.

 

For my own 108, I have swapped the speaker for a base reflex one and removed a block of seats from the middle of the coach. This is far from ideal, particularly for appearance as the speaker and wires are clearly seen through the windows. It does give me very good sound, though.

 

You may find that the round speaker you have will sit on the seat backs comfortably. However, when I tried this I found the sound was not very good - it was rather muffled as it couldn't escape from the coach interior! The bass reflex seems to pack more punch without cutting holes in the floor.

 

For the future, I want to replace the centre section of the circuit board with (perhaps) jumper wires and site the speaker protruding through the floor. Following that, I would be trying to replace the seating unit or, at worst, putting some seat backs on a bit of plasticard to hide the speaker. This does mean doing some major surgery to the base of the coach and it's not something I'm in a hurry to do! Having said all that, fitting your round speaker will take a lot less effort than fitting the long rectangular bass one I have.

[Andrew F]

The round speaker should take up exactly 2 rows of seats and it will sit on the PCB (in it's plastic enclosure!!!). It will be a tricky bit of surgery cutting an exact circle in the seating mould and the speaker will be slightly proud of the top of the seats leaving just small bits of the 2 seating rows remaining.

I don't really think that it's much of a hardship seeing the speaker there as the engine block encroaches into the passenger area anyway wiping a row of seats out and being visible through the window.

You could always fit it in the trailer and have a connecter if you run a 2 car set but I'm not sure it will fit vertically where the toilet block is and anyway, that's usually where the function decoder will be residing.

Like SR says, it will sound muffled and there will be no escape for the sound.

 

Cheers

 

Andrew

[brossard]

I carved away the seats about mid coach. I also spliced in an additional 1 in or so of wire since as delivered (from Howes) the speaker wires were a tad tight. In order to get the sound out I drilled 1/8" ish holes in the underframe and very carefully drilled the same size holes in the circuit board. It sounds pretty good to my ear.

 

John

[Guest 838rapid]

I have done mine quite differently to the ways described.

 

I have removed the Little mouldings on the underneath of the chassis and fitted the speaker there.

 

It involved removing a fixing from a corner of the pcb to gain access through it then feeding the wires through the holes left by the fixings.

 

I have then used the 23mm speaker facing down.

 

Sounds really good too

[Tony Burgess]

I had one on loan and the person who had fitted sound had the speaker inside with the seats but - and here's the thing - had arranged the doors to have open windows. From my own limited experience with fitting sound, I would suggest either below 'looking' down on to the rails, or upwards either through an etched grill or even under the coal load to give the best sound for locos. And always using a speaker enclosure or placing the speaker 'tight' against as open an aperture as possible bearing in mind the need to protect it from an inadvertant finger when handling.

 

Tony Burgess

[Mr.S.corn78]

Hi,

 

I have done a couple and always have installed the speaker in the seating area after removing some of the seats.

 

I have cut the hole for the speaker in the middle of the seats so it is harder to see when looking in through the windows.

I used a 40x20 with enclosure

 

I can't remember if I have cut some of the windows but with the size of speaker I don't think it needs it and sounds quite good as the sound escapes from the motor area.

 

Cheers

Simon

[jimhagan]

I have used a Zimo MX648R decoder from Digitrains plus 2 Eckig 8 ohm miniature "sugar cube" speakers wired in series and this is the good bit these speakers are so small they sit on top of the motor bogie weight and the decoder is so small as well it sits in the provided decoder receptacle. This way there is no modification to the model whatsoever.

 

The speakers are provided with sound boxes but are too deep to provide enough clearance on top of the weight, so are fitted using 1mm thick dense foam pads.

 

The other advantage I have found with Eckig speakers is that the wires are connected with small spring clips so no soldering either.

 

With two of these speakers installed the sound is equivalent to a standard speaker I just had to raise the sound volume a little using cv 266 on the decoder.

 

Wiil upload a photo when I can get round to it.   

[tender]

I have used a Zimo MX648R decoder from Digitrains plus 2 Eckig 8 ohm miniature "sugar cube" speakers wired in series and this is the good bit these speakers are so small they sit on top of the motor bogie weight and the decoder is so small as well it sits in the provided decoder receptacle. This way there is no modification to the model whatsoever.

 

The speakers are provided with sound boxes but are too deep to provide enough clearance on top of the weight, so are fitted using 1mm thick dense foam pads.

 

The other advantage I have found with Eckig speakers is that the wires are connected with small spring clips so no soldering either.

 

With two of these speakers installed the sound is equivalent to a standard speaker I just had to raise the sound volume a little using cv 266 on the decoder.

 

Wiil upload a photo when I can get round to it.   

Humm, without the sound box the sound is pretty 'thin' from these speakers. My 108 is fitted with these using the sound box by fitting them under the chassis. There's a detail box you can cut a hole in to fit facing down towards the track. Sounds much better. I also have a second speaker for the trailer car and will connect to the decoder with conductive couplings. Haven't got around to doing this yet.

I have some pictures at home I can upload later if you like.

Ray.

[jimhagan]

Hi Ray,

 

I agree initially I did find the sound was a bit thin, but that was before mounting the speakers on the foam pads which gets them a bit closer to the roof of the DMU then playing around with the volume.

 

As you did the first idea was to mount the speakers under the chassis as per the article by Paul Chetter in the January Hornby Magazine, which prompted me to get the Zimo MX648R decoder with his sound project from Digitrains (which I am most impressed with) and Eckig speakers, then wondered if there might be another way. 

 

There seems to be a lot of discussion about installing sound in the Bachmann DMU's which oftens involves some kind of surgery to the model however small. Having now installed sound in my 108 without doing anything major (apart from removing the two threaded projections on the top of the drive housing) and the sound quality is acceptable for my ears, compared to other sound equipped locos that I already run, I am happy with the results but may fabricate a pair of sound boxes to further improve things.

 

You are thinking along the same lines as me about installing sound in the non-powered driving unit, as mine is a three coach 108 with the sound coming from one end only!  I have been thinking about the means to do this as you have, either running wires with connectors through the train although this may overload the decoder, or going way over the top and installing a sound decoder in the other vehicle and disabling some of the sounds,  ie buzzers etc if that is possible.

 

If the photo below is produced then it shows the present state of play and may try and upload a video to You Tube with the sounds as produced.

 

https://dl.dropbox.com/u/53216221/Bachmann%20class%20108%20sound%20install%2025-01-2013%2011-43-10%203872x2592.JPG

 

Jim

[tender]

Here's a few pictures.

 

First the speaker with sound box mounted in the under chassis (before painting black)

 

 

and the decoder (Loksound 4.0 with Legomanbiffo sound file) mounted on the motor block

 

 

The trailer car will have a second speaker similarly fitted and wired in parallel to the first using conductive couplings so you get the engine sound from both cars. The Legomanbiffo sound file has a two engine start sequence so should give the impression for both engines starting (pity there's not a stereo sounder yet).

 

Ray.

[pauliebanger]

Hi Ray,

 

I agree initially I did find the sound was a bit thin, but that was before mounting the speakers on the foam pads which gets them a bit closer to the roof of the DMU then playing around with the volume.

 

As you did the first idea was to mount the speakers under the chassis as per the article by Paul Chetter in the January Hornby Magazine, which prompted me to get the Zimo MX648R decoder with his sound project from Digitrains (which I am most impressed with) and Eckig speakers, then wondered if there might be another way. 

 

There seems to be a lot of discussion about installing sound in the Bachmann DMU's which oftens involves some kind of surgery to the model however small. Having now installed sound in my 108 without doing anything major (apart from removing the two threaded projections on the top of the drive housing) and the sound quality is acceptable for my ears, compared to other sound equipped locos that I already run, I am happy with the results but may fabricate a pair of sound boxes to further improve things.

 

You are thinking along the same lines as me about installing sound in the non-powered driving unit, as mine is a three coach 108 with the sound coming from one end only!  I have been thinking about the means to do this as you have, either running wires with connectors through the train although this may overload the decoder, or going way over the top and installing a sound decoder in the other vehicle and disabling some of the sounds,  ie buzzers etc if that is possible.

 

If the photo below is produced then it shows the present state of play and may try and upload a video to You Tube with the sounds as produced.

 

https://dl.dropbox.com/u/53216221/Bachmann%20class%20108%20sound%20install%2025-01-2013%2011-43-10%203872x2592.JPG

 

Jim

 

 

Jim,

 

Glad you like my DMU sound project.

 

There is an error in the HM article at Step 14. It says 'wire in parallel' but should have been corrected to 'wire in series'. The optimum impedence for the MX648 (and MX646) is 8 ohms, which each Eckig speaker has. When wired in paralle, two 8 ohms speakers will have a combined impedence of 4 ohms. If you turn up the volume in these circumstances, the sound will show signs of cutting in and out, giving a crackly, distorted, output.

 

Regards the eckig speaker itself. The resonator is an integral part of the system and has a two-fold function. The first is to act as a resonator to increase the volume for a given decoder output. Secondly, it acts to dampen any excess movement of the driver, helping to prolong the life of the speaker and reduce distortion.

 

It may be possible to remove the enclosure, reduce its height by filing down the 'open' end, and shaving off some of the thickness in the 'top'. Alternatively, you may be able to fabricate an enclosure in the same way I did for fitting one inside a Farish 'N' gauge Class 47 in the current issue of HM.

 

So, wire in series and fit enclosures for a better sound and longer service life.

 

The ZIMO sound project you have has a twin engine start - each power car has two engines, so that's what you would expect. Often the second  vehicle is unpowered (Driving trailer).

 

As a matter of interest (to me), are you using the manual gearchange sound set (default) or the 'normal' auto scheme?

 

Good luck and kind regards,

 

Paul

[jimhagan]

Thank you both for your comments very useful information. Ray's photos also show the resonators in place which I will now fit as Paul advised.

 

I have been using the default sound settings so far, but as I am in the process of rebuilding my layout and do not have a rolling road as yet cannot get the true driving experience!

 

I have already wired the speakers in series,and found no problem providing the volume is not high enough to cause distortion, having found a level which is acceptable.

 

I have read countless description on how to go about installing sound in the 108 and it was the Hornby article which Paul produced which finally caught my imagination as to a more viable solution without cutting out rows of seats. The combination of Zimo mx648r and Eckig speakers is now going to be used for another sound project my Hornby 08.

 

And just for fun I bought a Bachmann Junior saddle tank which now has a decoder in it and have an MRC sound only decoder which I want to put iñ with an Eckig speaker, not sure if there is enough room for a seuthe smoke unit though!

 

And thank you the info about the driving trailer no need to install in that phew!

 

 

 

Thanks a lot Jim

[jimhagan]

Changed my mind and put the speakers with resonators underneath afterall, did the same as Paul so the speakers are pointing up found it easier to fit the speaker wires that way. I am very pleased with the result especially the sound which really does come from the engines underneath as per the prototype!

 

Have done a video featuring all the sounds which will be uploaded to You Tube soon.

 

Jim

[jimhagan]

Have now uploaded a video of my class 108 to YouTube showing the installation of Eckig sugar cube speakers beneath the powered unit and demonstrating the various sounds.

 

The sound quality is much better in real life but I hope it helps illustrate the neat way Eckig speakers can be used under the class 108 or similar dmu models.

 

Click hear to view 

 

Hope you like it.

 

Jim