Exmaple 1 - removed weight, big speaker and stay-alive

Kit: MX645, LS40X22X09-2W Dual Dumbo, SACC16 with SuperCap17000

A really easy DCC Sound install of this fantastic model would be the MX644D with an LS26X20X08-1W Dumbo - plug-and-play, but we wanted a challenge to fit a dual Dumbo speaker and a 17000uF SuperCap for stay-alive...

Pause for a moment to show how easy the MX644D 21pin decoder and LS26X20X08-1W Dumbo would fit, before we continue...

That's a lot of kit to get in the tender, so we need to strip it down first... remove the weights and the 21pin DCC socket, and flatten the round speaker mount on the base of the tender.

We remove the MX645's heat shrink and take away any unrequired wires (lighting), then re-cover with Kapton tape.

Solder the pickups and motor wires onto the connection board (worth doing a line-test to check which ones are which before you start!)

SuperCap sits on the floor, with dual Dumbo speaker on top. Tight, but not too difficult.

The results are even better than we expected - the performance from the stay-alive is excellent (around 5 seconds backup time) and the dual Dumbo works very well with the tender shape and is very loud with a great full sound.

Example 2: retained weight, still decent speaker and stay-alive

Kit: MX644D; SugarStrand25X20X08; LifeLink+17000uF SuperCap

We take a slightly different approach with this lovely umber H2, retaining the metal weights in the tender, so the speaker needs to be a little bit smaller, but not much...

The factory-installed capacitor can be removed, as we'll have our own SuperCap to do the stay-alive. An 8mm dual SugarStrand speaker will sit on top of the weights - perfect (but comfortable) height without any need to modify the tender). A 17000uF SuperCap will sit in position at the front of the tender.

Add wires to the SuperCap, covering it will Kapton tape for insulation, then attach to a LifeLink PCB (needed on the MX644 to sit between the decoder and capacitor).

The LifeLink is then wired to the MX644's stay-alive pads.

Connect the speaker's wires to the solder tabs provided in the model.

Plug in the decoder, and slot the LifeLink (wrapped in Kapton tape) under the model's PCB.

All finished, sounds great, runs smoothly, and has excellent back up power from the SuperCap.

Please note that these guides are provided as useful resources for you, as-is. YouChoos cannot be held responsible for errors in the information, or for any damage caused to your models or equipment if you choose to follow any of the steps detailed here.