Speed Matching Sound Value Locos

[jwb]

In the thread on Sound Value FA2s, it was suggested that I start a thread on speed matching Sound Value HO locos with other makes on DCC. In particular, I think these are potentially good mates for Atlas/Kato or Classic GP7s and RS-3s with DCC decoders installed, but out of the box, they don't match well in speed. The recent Sound Value locos are especially comparable in detail to the older Atlas yellowbox locos -- the GP7s in particular seem to have been retired from the Atlas line, so the Sound Value GP7s fill an important gap here.

Has anyone had experience with this?

[jwb]

OK, here's a start. I decided to speed match a Sound Value NYC F7A with a Bachmann NYC GP30 equipped with a Digitrax DN136PS decoder.

I've noticed that the several Sound Value locos I've worked with all have very low starting voltages and very high speed curves. They start more quickly and run faster than decoder equipped Atlas Kato units, as well as ordinary Bachmann units without sound. As a result, due to the very low starting voltage of Sound Value, it looks like I will need to raise the starting voltages of other locos I need to speed match. I also need to slow down VMid and VMax on the Sound Value locos.

Following Hunt's recommendation in this thread http://www.bachmanntrains.com/home-usa/board/index.php/topic,28310.0.html I reset CV 25 = 0 and CV 29 = 2 on the F7A. Then I took the Dgitrax recommended values for CV02 =002, CV06=038, CV05=064, which is the slowest speed curve they recommend. This didn't seem to have any effect -- not sure if I did this right or not. Hunt, can you confirm this?

Then I tried to speed up the GP30. I wound up setting CV02=30 and CV06=200, didn't touch CV05 on this loco. This wound up with a barely acceptable match.

Has anyone else played around with this?

[Hunt]

jwb,

What DCC system are you using? If Digitrax Zephyr Xtra DCS 51 or the discontinued Zephyr DCS 50 you may not have been successful programming the Bachmann Sound Value decoder CVs to a new value. I am aware of programming issues with each Zephyr and a SoundTraxx Tsunami but not with a Sound Value decoder.

Can you change the locomotive address from 2 digit to a 4 digit and control it with new address?   From the 4 digit to a 2 digit address?

Are you using Operations Mode (Ops Mode) programming or Service Mode programming (programming track) in Direct Mode?

[jwb]

I'm using an NCE Power Cab, and I did the reprogramming with the Program on Main feature. I'm able to change the Sound Value address (on Programming Track) to four digit from 003 default, but haven't tried to change it back. Maybe I need to try changing the speed curve on the Programming Track with the Sound Value loco.

[Hunt]

The result of the address change test was only useful if you were using a Digitrax Zephyr.

Programming on the Main (OPS Mode) is what to use when setting a speed curve. You can use Program Tack (Service Mode) feature but it requires more steps to obtain the speed you want as you have to switch out of Program Track to see the effect.

Recall, do not use leading zeros when programming any brand decoder with a NCE Power Cab except as explained in the NCE Power Cab manual (not the decoder instructions).

You may find easier if BEMF is turned off.