pauliebanger

The difference is only that ESU supply a speaker (which many throw away) and Zimo allows you to choose your own type. (or as others might see it, they do not supply a speaker. Ha Ha) The brand has no bearing on the difficulty of fitting at all.It's the connection type that's important (though it is possible to work around any mismatch as the decoders themselves are the same, just the connections differ) Both ESU and Zimo, (and most others) supply either plain wired or 8-pin or 21pin connector versions of their decoders (sound or otherwise!) Make your brand choice, then buy the correct connector type. Bachmann do make it easier as they usually quote the connector type in their brochures. The difficulty/easiness of the job is far more dependant upon what you find inside the model than the decoder. Paul * I made some edits to this post so that it makes more sense in relation to phaeton's post.

Steve, Depends on the connector type. 8 pin connectors were speciied way before sound so no pins were designated for speaker wires. All 8 pin (and plain wired) sound decoders have separate speaker wires which do not go through the connection. (The same applies to higher Function Outputs too). In an attempt to overcome this, the 21 pin MTC connector was introduced, mainly by European manufactures. This has lots more connections and incorporates the speaker connections so no wires are needed from the decoder. The circuit to the speaker needs to be completed by connecting to the 'Loco side' of the 21 pin connector, usually via the circuit board. All decoders can be soldered into most (all?)locos, but thats a lot of work in some cases. If your loco is DCC ready, including those fitted already with non-sound decoders, it makes sense (for simplicity) in most cases to use the existing connectors. But you need decoders with the correct connectors - important info before you buy! Bachmann make much use of 21-pin interface. Your 66 is fitted for a 21-pin decoder, I believe, so look for 21 pin decoder. As you are new to this, I suggest you choose decoders from either ESU or ZIMO. The merits of each brand have been discussed here quite a lot recently. Both will do a good job out of the box. There are other brands, but they will need a lot of work on your behalf to get them to sound OK. Not recommended for beginners and non-geeks!! Kind regards, Paul

Here is my Hornby Class 4MT project running on 'Bay Street Shed' Sorry, don't know how to post direct link. Kind regards, Paul