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QUOTE (Hampshire @ 27 Jan 2008, 06:38) <{POST_SNAPBACK}>Hi,

I've recently entered the world of DCC, espically DCC sound chips. Overall, I am pleased with the performance of my factory fitted class 20 sound chip (once I'd adjusted the volume !).

However, I've recently expanded my sound fleet, with the purchase of a class 66 (shanks) and Class 37 (Coal Sector) but have found that both these models do not perform nearly as well as the class 20. With major lags between slowing down and the sound catching up, engine shut down sequnecies not work etc.

I've have been trawling the various forums to look for posts on the CV values that need adjusting to resolve these type of issues, but haven't really found any clear answers, so I was hoping those who may have had DCC sound for sometime, or have already revised the CV values may be able to offer these settings to the forum for any of the factory fitted decoders.

I appreciate that sound is a very subjective topic, but any suggestions would be welcomed.


Copied from my posts on another forum!

Right, done some more u-tubing now that 37114 with its bachmann version of the mk 4swd class 37 chip, has a base speaker fitted in the tanks and the fan has been modded.

This is 37886 which has twin 23 ml speakers in the tank and a swd mk 4 chip fitted, starting up.

This is 37114 bachmann cl 37 sound chip starting up. You should be able to hear the difference, its a bit more throaty/basy.

This is the pair starting up together, them me testing the horns, buffer clas that are much the same on each project. There is a noticable difference in the horns.
Swd + twin speaker in 37886 first, then 37114.

This is the pair double heading

This is me using notching on the bachmann 37114 chip, after base speakers.

Not really used them enough to draw a final comparison, but here is a difference, although small between the two sounds. this for me is good as variety adds interest. The bachmann chip really would be much better if they had instructed Swd to add the air release and flange squeal on an F key.

At the moment, i dont think there is anything between the two.

However, the addition of the Dcc supplies speaker in the tank and the removal of the fan holder to allow more sound to escape from under the fan has greatkly improved the sound from the bachmann 37 chiip..

Important Cv values as the chip came were

CV3 Acceleration, was set at 20, moved to 30 (Swd mk 4 set at 30)
Cv4 Decceleration rat, was set at 20, left at 20 (Swd mk4 = 24)
Cv5 Max speed, was set at 39, left at 39 (SWD mk4 = 40)
Cv6 Medium speed,was set ar 20, left at 20 (SWD mk4 = 20)
Cv63 was set at 50, for testing i set to 64
Cv64 (annoying brak squeal) was et at 7, i reduced to 1

The above, using notching up gives loads of play value in accelerating away light engine of with a heavey train. Might have to tweak a cv here and there for double heading, but hey its worth it!
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