Which Tsunami for the ALCo S2?

[Searsport]

Hi, my on-line hobby shop now has the DCC ready Bachmann #63307 ALCO S2 Diesel Switcher Western Pacific #562 in stock.  However, when I looked at the MB Klein website, I found two Tsunamis for the ALCo S2 / S4.  These were:

SoundTraxx Micro-Tsunami Decoder 827012 (TSU-750) for Alco 539 Turbocharged Diesel Engines

SoundTraxx Tsunami Decoder 828049 (TSU-AT1000) for Alco 539 Turbocharged Diesel Engines

Can anyone advise on which is the most appropriate for the Bachmann S2?

I assume the TSU-1000 is better than the TSU-750, but will it be a straightforward fit in the Bachmann S2?  This will be the first loco I have fitted myself.

Grateful for advice,
Bill.

[Tom M.]

I would suggest an alternative approach.  Purchase a sound equipped Bachmann S4 and swap the shell with the Bachmann S2.  I believe if you shop around you will find that purchasing the Sound Value S4 to be cost neutral when compared to buying the full-featured Tsunami plus speaker and enclosure.  You will also find this alternative approach much easier to complete.

I have installed the T-750 in several Atlas S2 and S4 locos.  I also have a couple of the Bachmann S4 sound locos.  There isn't enough room in either of them to install the T-1000 (at least without doing a lot of heavy duty surgery).  The plus to using the Atlas loco is weight which equates to pulling power.  The Atlas frame is a very heavy chunk of cast metal.  It has much more pulling power than the lighter weight Bachmann unit.

Tom

[Searsport]

Hi, Tom, thanks for your reply.  I was specifically seeking the sounds appropriate to switching which the Sound Value unit does not have, especially brake squeal and coupler clank.  Maybe the TSU-750 unit is the way to go?  The Soundtraxx decoder selector points to the TSU-AT1000 for the Bachmann S4, but the MB Klein website says this is "designed specifically for recent production Bowser-Stewart HO diesels", which I am not familiar with.  But the Soundtraxx selector also recommends an oval speaker for the Bachmann S4, which clearly does not look like it would fit the round mounting location shown on the Bachmann S4 service sheet on this website, so I am sceptical of the Soundtraxx recommendations.  I had assumed that as the S2 / S4 body is designed to house a Tsunami of some kind then one or other of the 750 or 1000 might be a simple drop-in.  An alternative for a small WP silver and orange switcher would be the Bowser Baldwin VO-1000 with a Tsunami already fitted, and which is also available with two road numbers, so I could get two for Christmas!!

Thanks,
Bill.

[Searsport]

Hi, I have now looked inside a Sound Value S4, and the decoder is 3.8" long x 0.7" wide.  The SoundTraxx website says that the TSU-1000 is 1.7" long x 0.67" wide.  This suggests that the body is wide enough and the difficulty in fitting a TSU-1000 into a DCC ready S2 or S4 lies in finding a fixing point for one end of the decoder.  Is this correct, or are there other problems?

On and S2 / S4 body swap, it would also be necessary to swap the bogie sideframes, but that looks to be straightforward, as they seem to be a clip-on plastic moulding quite independent of the wheels, gears, etc.

TIA,
Bill.

[richg]

The 750 was mentioned. Those are sensitive to heat buildup. I have seen quite a few discussions in the Yahoo SoundTraxx Group. Users have to attach a piece of aluminum to the bottom of the decoder with heat sink paste between the metal plate and bottom of the decoder.
I have had that issue with one TSU-750 and substituted a TSU-1000.

I use the TSU-AT1000 and the TSU-1000with no issues.
Rich