Browse Categories
Browse by Manufacturer
Mailing Lists

THT Kato GS4 Sound package (N Scale) - purchase loco separately

Select type

This Package includes the decoder and work as described below.

  • Custom hard wire motor from Tender to Loco
  • Custom hard wire Decoder
  • Install Rear Light (LED)
  • Custom wire and  alter Loco light board and rewire Mars light.  We reuse the existing LED. 
  • Do appropriate mods to the tender and weight to allow decoder install.  (Maintain tender weight to avoid jumping track).
  • Custom program decoder and test installation
DCC Sound installation:


We spent the better part of 3 days looking over the Kato GS4.  To do this right the install takes about 4 hours with the programming and testing another hour.  We could have just added the decoder and ended it at that but the loco really calls out for the additional details.  We decided to do the following to make this loco come to life.

We chose the SoundTraxx Sound decoder to compliment this excellent running and looking loco.  With the programmable features the loco really becomes a living breathing iron horse.  Here is what we did:

  • Hardwired the motor feed from the tender.  To correct the issue of DCC shorting as discussed on the Kato Website we decided to hard wire the motor circuit eliminating the problem.  This of course requires wires be fed from the loco to the tender but since we were going to wire up the Mars light anyway, we decided to make this part of the standard modification.
  • Mill the tender weight and replaced it to keep tender rail tracking.  This is a very important detail.  Without the proper weighting the tender will have a tendency to jump the rails.  It may seem simple enough but the weight needs milled to allow the tender shell to fit properly.
  • Added the SoundTraxx 810112 oval speaker to the tender.
  • Since Kato does not have a NMRA 8 pin plug the decoder needs to be hard wired.
  • Modified the Loco light board to allow the SoundTraxx hyper light Mars light to be controlled via DCC.  This replaces the simple blinking light from the manufacturer.
  • Added a Tender backup light (LED) controlled via DCC
  • Custom programmed the decoder to take advantage of the features. 
  • Note: We do not try to insulate the drivers using tape or Kato driver shields.  We insulate the upper portion of the frame from the motor and motor circuit.  This approach eliminates the problem so there is no chance of the tape rubbing off causing your expensive decoder to fail.  This is a more labor intensive solution but one that yields a superior outcome and performance.
  • Extensive testing over our demo layout.

We know that this is not an inexpensive package but the results are outstanding.  Using the Kato GS4 as the platform for this upgrade is a winning combination.

TopHobbyTrains famous Kato GS4 Sound package with simulated Mars lighting and Tsunmi Micro Sound

To have a Kato GS-4 locomotive that you already own upgraded to TopHobbyTrains GS-4 Sound please purchase this package and send your loco to us with a copy of the invoice to: 

 Click here for Shipping information to TopHobbyTrains:


Manufacturer: TopHobbyTrains
Mfr Part No: THTGS4Sound

Product Reviews

(0 Ratings, 0 Reviews)