On30 Whitcomb 50-ton switcher - add my own DCC decoder

[Grapevine Flyer]

I purchased an On30 Whitcomb 50-ton center cab diesel.  It says "Sound Ready - DCC equipped". My definite intent is to put a specific DCC decoder in it (Blunai). I thought it came with a standard 21-pin decoder connector - and that I could just plug into that.  As I'm looking through it with the shell open, it mentions a "Whitcomb sound module" and I'm starting to question if I can just plug in a decoder so easily.

What is the process for me putting my own decoder (Blunami) inside this loco?

[Hunt]

To use a Blunami decoder in Bachmann On30 Whitcomb 50-ton switcher:

• Replace the factory installed DCC decoder (made for Bachmann by SoundTraxx). 
• Replace the factory installed speaker with one compatible with the Blunami 2-watt audio amplifier.
  

[Grapevine Flyer]

Thank you. I don't visibly see a bachmann decoder. It just looks like a whole circuit board. It has a 21-pin connection, but I'm getting the impression I can't just attach a decoder to that 21 pin connector (is that for a proprietary sound board?). Is that true?

Also, these 2 speakers that came in the loco won't work with Blunami? I can swap them out if necessary - just want to confirm.

I was hoping I could just pop a decoder on the 21-pin connector, but it sounds like I need to remove all electronics from this train in order to use a Blunami. Is that true?

[Hunt]

Thank you. I don't visibly see a bachmann decoder. It just looks like a whole circuit board. It has a 21-pin connection, but I'm getting the impression I can't just attach a decoder to that 21 pin connector (is that for a proprietary sound board?). Is that true?

True

Also, these 2 speakers that came in the loco won't work with Blunami? I can swap them out if necessary - just want to confirm.

Only can be used if CV 128 Master Volume is set to a low value. I don't recall the value at which speaker damage will occur. Phone Bachmann Service Dept for the value (don't be surprised if they do not know). 

I was hoping I could just pop a decoder on the 21-pin connector, but it sounds like I need to remove all electronics from this train in order to use a Blunami. Is that true?

True