Model Railway Forum banner
1 - 13 of 13 Posts

·
Registered
Joined
·
982 Posts
Discussion Starter · #1 ·
Over on MREmag a contributor has pointed out that SW Digital has got a new DCC sound chip for a class 37 and that this also works on DC. I understand that in the US some manufacturers actually produce locos that have sound that works on DC as well as DCC.

There are, of course , some compromises, functionality on DC being limited to engine noise whereas with DCC you would get shunting noises, wheel flange squeel and a horn.

Bachmann have brought out a 20,47 and 66 with DCC sound but as far as I'm aware the sound doesn't work on DC. Why should this be? Is it a deliberate plan to give sound DCC exclusivity in this
country and to get people to sign up for DCC on the basis that this will be the only way they get sound.

This is not a DC v DCC argument, but what do people think- why should DC'ers not have sound available to them? No doubt Hornby will enter the fray soon- they could steel a march on Bachmann if their sound worked on DC as well as DCC. However given Hornbys investment in Digital and their desire to extract maximum £ from the enthusiast I really doubt they'll go down this route.

Russell
 

·
No Longer Active.
Joined
·
13,319 Posts
It may be that the sound decoders factory fitted to mainstream UK models are not full spec' - I don't know this for a fact & stand to be corrected.

Both my Fleischmann & Trix BR218 Diesels with factory fitted sound decoders have very limited sound functions on DC, so maybe this is just how they are.

AFAIK some US sound decoders are better on DC than their european counterparts.
 

·
Premium Member
Joined
·
7,397 Posts
QSI decoders which are fitted to Broadway Limited and the Australian Eureka models are designed to operate on analogue DC and DCC. While I don't think these are the best sound decoders they are designed to fully function on analogue DC and present a good option for analogue DC modellers.
 

·
Registered
Joined
·
43 Posts
QUOTE (rb277170 @ 24 Sep 2007, 20:10) <{POST_SNAPBACK}>Bachmann have brought out a 20,47 and 66 with DCC sound but as far as I'm aware the sound doesn't work on DC. Why should this be? Is it a deliberate plan to give sound DCC exclusivity in this
country and to get people to sign up for DCC on the basis that this will be the only way they get sound.

In how much that plays a part in their thinking, they will ill reveal to anyone. It is a result of their choice of decoder. Don't bachmann use ESU decoders? I think these do not perform on DC.

It kind of makes sense to look at DCC as a the way forward (oh - no, tin hat on now)


Walter
 

·
No Longer Active.
Joined
·
13,319 Posts
QUOTE (Walter @ 25 Sep 2007, 07:36) <{POST_SNAPBACK}>. Don't bachmann use ESU decoders? I think these do not perform on DC.
Walter

Certainly the ESU decoders factory fitted to my Fleischmann locomotives operate in a limited manner on DC (see my post above).
 

·
Registered
Joined
·
3 Posts
QUOTE (dbclass50 @ 25 Sep 2007, 07:46) <{POST_SNAPBACK}>Certainly the ESU decoders factory fitted to my Fleischmann locomotives operate in a limited manner on DC (see my post above).

On my Bachmann Class 20, I set CV 13 to 1, which gives limited DC usage (full start up once the controller gets about halfway, and then running sounds). This is fine on a continuous layout, but a pain on a point-to-point one as reversing direction causes a full start-up each time!

Cheers,

Dave
 

·
Registered
Joined
·
43 Posts
QUOTE (Dave Searle @ 25 Sep 2007, 10:02) <{POST_SNAPBACK}>On my Bachmann Class 20, I set CV 13 to 1, which gives limited DC usage (full start up once the controller gets about halfway, and then running sounds). This is fine on a continuous layout, but a pain on a point-to-point one as reversing direction causes a full start-up each time!

Cheers,

Dave

That's probably a good example of the extent to which sound decoders will do anything on DC. With the way sound decoders work, there has to be an analogue-to-digital handover/conversion at some point and the chip will probably be able to pick up on a certain voltage and produce digital sound commands according to some factory setting on how to behave on DC. Other than that, you'd probably never ever be able to produce anything other than running sounds on DC.

In that sense, you really cannot separate sound from DCC and it makes sense for manufacturers to push this as such. Of course they then want you to buy their gear, but that's another matter!

Walter
 

·
Premium Member
Joined
·
7,397 Posts
QUOTE (Walter @ 26 Sep 2007, 01:32) <{POST_SNAPBACK}>That's probably a good example of the extent to which sound decoders will do anything on DC. With the way sound decoders work, there has to be an analogue-to-digital handover/conversion at some point and the chip will probably be able to pick up on a certain voltage and produce digital sound commands according to some factory setting on how to behave on DC. Other than that, you'd probably never ever be able to produce anything other than running sounds on DC.

In that sense, you really cannot separate sound from DCC and it makes sense for manufacturers to push this as such. Of course they then want you to buy their gear, but that's another matter!

Walter
As I said previously the QSI sound works perfectly well on analogue dc. You have the full range of sound functions and can change between them by toggling back and forward quickly on the power.
 

·
Registered
Joined
·
2,151 Posts
MRC has a new gadget for DC users called the "blackbox" which has both steam and diesel sounds available.

A more crude but equally effective is the NOCH sound module for DC users. I used this one and was quite happy with the results.



Baykal
 

·
Premium Member
Joined
·
338 Posts
At the risk of jumping in where angels fear to tread...

I cannot see that there is any technical reason why a sound generator cannot be designed that could accept, say, pairs of audio tones (similar to tone dialling on a phone) and, combined with an A to D converter, automatically produce the sound of a train starting up, accelerating and running at speed. The operator would have to initiate the process manually. With 3 frequencies one could have 3 commands (A+B, A+C and B+C). Four tones would give 6 commands, etc. Some commands would have to be paired to give on/off (diesel engine sound/steam loco sound) while others would be stand-alone (e.g. whistle/horn, venting steam). The same frequencies coudl be used for all locos on a layout as the signals would be limited to the loco being driven by a particular controller.

However, I cannot see it ever happening. :eek:(

All the best,
Chris.

PS added as an afterthought. Could one actually generate the sounds in the controller and superimpose them onto the DC voltage. All the loco woudl need then is a small speaker to make the appropriate noises. (There would have to be at least a capacitor in series with it to prevent dc reaching the speaker.) Would relatively low level audio signals have any effect on the motor?
 

·
Registered
Joined
·
370 Posts
It seems to me that the possibility of UK outline DC locos with sound is remote.
I suspect that it's a commercial thing to encourage more converts to DCC.
Although I'm quite happy to continue with my DC equipment, the one thing that could influence me is the availability of DCC sound. Fortunately for my pocket, UK steam sounds are still not easily (or cheaply) available, so the temptation to go to DCC is not so strong. Having said that, UK manufacturers, especially Hornby seem to be pushing DCC hard as the future of the hobby. Pity then that the Dcc equipment they produce is not up to the standard of the major DCC players in Europe and the US.
 

·
Premium Member
Joined
·
338 Posts
Hi Jeff.

I agree, your answer sums it all up - commercial pressure. DCC isn't an option for me (though I do have half a dozen or so digital locos) as I have a large collection of (physically and in outline) old locos that cannot be fitted. Oh well.

All the best,
Chris
 
1 - 13 of 13 Posts
Top