DCC Sound

[rugbyboys]

I got a sound chip fitted to a loco and everything works fine, sounds lights etc but even on full power it runs a bit slow is this right any suggestions please.

[Gregd99]

When you say "a bit slow" it is not clear how slow you mean.

 

typically locos can run faster than their scale maximum speed under dc. this is particularly true of some of teh cheaper locos. For example I have a cheap 0-6-0 that will do about 200

 

(scale) km/h whereas perhaps 50-80kim/h might be more reasonable.

 

Ofetn people say the loco will not run at full speed under dcc when in fact it often still exceeds the scale maximum speed.

Can you calculate the speed that you loco is running at?

 

perhaps all is well or perhaps there is an issue.

[rugbyboys]

Gregd99 said:

When you say "a bit slow" it is not clear how slow you mean.

typically locos can run faster than their scale maximum speed under dc. this is particularly true of some of teh cheaper locos. For example I have a cheap 0-6-0

that will do about 200 (scale) km/h whereas perhaps 50-80kim/h might be more reasonable.

Ofetn people say the loco will not run at full speed under dcc when in fact it often still exceeds the scale maximum speed.
Can you calculate the speed that

you loco is running at? perhaps all is well or perhaps there is an issue.

[rugbyboys]

Hi Gregd99, I know it is difficult to define slow when you cant actually see the job but compared to the other locos running on the track at the same time and them running on less than half power and it on full power it runs slower than half their speed,

 

but the only other experience I have with DCC sound is a Hornby Clann class I own which runs much faster that this so I hav`nt anything else to compare it with, many thanks for your help it is a great help.

[Graskie]

Exactly what loco are you having trouble with, RB? What controller are you using?

[rugbyboys]

Graskie said:

Exactly what loco are you having trouble with, RB? What controller are you using?

[rugbyboys]

Hi, its a class 37 from the other side you know the name starts with a B and I am using a Elite controller,hope that this helps,many thanks.

[stevecamden]

Having the sound turned on draws more power and I think this is the reason why it is slower. Well I have a 37 too with sound from B and that is what I assumed anyway. But since, it goes fast enough ( I rarely run anything close to max speed) it has never

 

been an issue for me.

 

In fact, generally, my issues are about getting stuff with sound to run smoothly at very slow speeds which I am beginning to think without a 'stay alive' power source is near impossible.

[Gregd99]

rugbyboys said:
compared to the other locos running on the track at the same time and them running on less than half power and it on full power it runs slower than half their speed

It is worth looking at the scale speed.

If

I google class 37 I see that the max speed was between 130 and 140km/h. Let take 120km/h as a normal running speed.

using 1/76 as the OO scale and 3600 s/hour I come up with 120km/hr (I hope I did this right) being equivalent to taking 2.3 seconds to

cover a 1 metre distance. I have a speedo set up that measures time between sensors but you can roughly time it with a stop watch or a watch.

if your class 37 is taking 5-6 seconds to cover a one metre distance then it is SLOW. if it is taking around

2 seconds then it is normal.

let us know what you measure.

btw I find that I reduce speed to around 2/3 of max as a "realistic max" on my 1.2 x 2.7 m layout. Any faster doesn't feel right.

[rugbyboys]

Gregd99 said:

rugbyboys said:
compared to the other locos running on the track at the same time and them running on less than half power and it on full power it runs slower than half their speed
It is worth looking at the scale speed.

If

I google class 37 I see that the max speed was between 130 and 140km/h. Let take 120km/h as a normal running speed.

using 1/76 as the OO scale and 3600 s/hour I come up with 120km/hr (I hope I did this right) being equivalent to taking 2.3 seconds to

cover a 1 metre distance. I have a speedo set up that measures time between sensors but you can roughly time it with a stop watch or a watch.

if your class 37 is taking 5-6 seconds to cover a one metre distance then it is SLOW. if it is taking around

2 seconds then it is normal.

let us know what you measure.

btw I find that I reduce speed to around 2/3 of max as a "realistic max" on my 1.2 x 2.7 m layout. Any faster doesn't feel right.

[rugbyboys]

Hi Gregd99, it is taking approx 5 seconds to cover a metre so i think that it is running slow.

[rugbyboys]

Cheers Thanx.

[Rog RJ]

If it's a Loksound V4 decoder the maximum speed value for CV5 is 255. The default value is 64.

[Gregd99]

rugbyboys said
Hi Gregd99, it is taking approx 5 seconds to cover a metre so i think that it is running slow.

that would be around 60 scale km/h so indeed slow.

Rog (RJ) said:

If it's a Loksound V4 decoder

the maximum speed value for CV5 is 255. The default value is 64.

That's interesting. maybe the top speed increase is not exactly proportion to the maximum voltage but that could indicate that the top speed could be increased by up to 4x. To be honest

I am impressed to see a decoder manufacturer giving headroom but at the same time not maxing out the speed.

Based on my sums that would mean a top scale speed of up to 240km/h!!

@rugbyboys - why not try it at 128 and see what happens. The scale

target should be around 2 and a bit seconds over 1m.

[morairamike]

This will ahve to do with the CV settings that the programmer used when the sound was put on the chip. I have a competitors Class 20 with sound which when it arrived was slow to my mind compared to my other locos. using my controller I looked ta the Cvs

 

and noted the values. I sent the unit to a well known relower of chips in Oxford and when it returned I noted that the Cv were now different and the top speed faster.

 

Beware though when changing CVs on a sound loco as it can change sound output like

 

the thrash etc.

[morairamike]

Just dug out my ESU Loksound 3.5 manual that came with the class20. original CV5 was 64 range is 0-64, after howes blew it it is 51 CV6 was 22 now 21. Bigest cahnges were in the acc dec Cv3 and 4 were 8 & 6 but now 30 & 11

[Blackbird]

Using a 'basic' controller, I can't see the 'sound' current requirement affecting the speed. I would suggest checking the decoder CV max speed settings, which are adjustable.

[Gregd99]

Gregd99 said:

@rugbyboys - why not try it at 128 and see what happens. The scale target should be around 2 and a bit seconds over 1m.

@rugbyboys - how did you go with this problem?