Selecting TTS decoders for non TTS locos

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Steve M
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Selecting TTS decoders for non TTS locos

#1

Post by Steve M »

I know this is a subject that comes up from time to time but I can never find any answers when I go looking for them - so here goes again.

The limitations of TTS decoders are well documented e.g. Chuff rates and synchronisation but at the price they are good enough for me. The issue comes when a loco 'needs' sound but Hornby don't yet produce a type specific decoder.

The usual advice is to pick a decoder from a loco with the same number of cylinders as the one you want to fit it to but then you get into the realms of the whistle not matching - a GWR whistle would probably sound wrong coming from a 'northern' loco.

For me it gets more complex when faced with a choice of decoders, for example I've just ordered a Bachman GNR 'atlantic' 4-4-2, two outside cylinders. Hornby won't be producing a decoder for it so a quick look at available TTS decoders that might do are the J36, Black 5 or Britannia - all two cylinders.

But how the heck do I choose which one is most suitable?
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RAF96
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Re: Selecting TTS decoders for non TTS locos

#2

Post by RAF96 »

Number of cylinders determines the basic chuff noise. The size of the ‘donor’ loco e.g. 0-6-0 or Pacific determines the ‘size’ feel of the chuff, then it boils down to whistles for steamers or horns for diesels.

Diesels - try to match engine type although the same engine in a different loco can sound different, then add horns, or any other defining characteristic, etc e.g. turbo howl, fans, etc.
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Re: Selecting TTS decoders for non TTS locos

#3

Post by Steve M »

Thanks Rob, based on that I reckon the J36 when it’s released may be a bit ‘light’ for the Atlantic - guess I’ll have to sample the Brit when that becomes available.
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Re: Selecting TTS decoders for non TTS locos

#4

Post by mijj »

How can anyone match a whistle/horn to a loco if one has no knowledge of these things :) .
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Re: Selecting TTS decoders for non TTS locos

#5

Post by Walkingthedog »

All steam locos sound the same to me except for the whistle.
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Re: Selecting TTS decoders for non TTS locos

#6

Post by Steve M »

mijj wrote: Tue Jul 30, 2019 8:33 pm How can anyone match a whistle/horn to a loco if one has no knowledge of these things :) .
Jim.
It’s probably only a purist that would notice but I would expect steam whistles from any given operator to be similar.

In my case I believe the Atlantic was an Ivatt design for the GNR, later LNER so I’m assuming that either an LMS or LNER whistle (not an A4 chime) would be close. Hence my comment regarding the Black 5 or J36.

But the Atlantic is referred to as ‘big boiler’ so I’m thinking the J36 may be a bit asthmatic as a stand in. I’d considered the Britannia class as a possibility as it is a larger loco and was designed by Riddles but I believe it shares many characteristics of the Bulleid Pacifics so maybe it’s not ‘northern’ enough for what I want.

As an aside I wonder if Hornby ever thought of doing the TTS as a more generic decoder ie three different decoders to cover 2,3 or 4 cylinders with user selectable whistles instead of some of th3 more gimmicky soundtracks - F4 for GWR, F5 for SR etc?
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Re: Selecting TTS decoders for non TTS locos

#7

Post by RAF96 »

I suggested just that to them Steve, generic steam and diesel selections in light and heavy variants of each, with a selection of whistles and horns, but it sort of fell on deaf ears for various reasons.

Each variant would require as much channel memory as any single loco due e.g to steamers needing bemf to control chuff/coast and the various multiple ‘brackets’ of sound bites that make up the chuff range. Diesels are bot much easier again due to sound bites for engine notching. As the TTS decoder is only twin channel that seems to me the limit would be 2 variants with no scope for various bells and whistles channels.
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Re: Selecting TTS decoders for non TTS locos

#8

Post by Steve M »

It can’t be beyond the wit of man (or woman) to create an acceptable generic solution.

Actually it’s already been done - just before TTS came out I did buy a configurable sound decoder for about £40 and I was fiddling with it only this morning.

It had CVs for 2/3/4 cylinders, standard or chime whistles with adjustable tone, adjustable chuff rates, tone and volume, in fact everything I needed. But the cost was low because it was way too big to be of much use.

I reckon Hornby are missing a trick. TTS is not perfect but it ticks most boxes but could be so much better if there were a bit more variety and availability - and something that suits and fits some of the tank locos in the range. All the alternatives are way too expensive to keep my marriage intact. :D
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Re: Selecting TTS decoders for non TTS locos

#9

Post by Tallpaul70 »

Steve M wrote: Tue Jul 30, 2019 9:06 pm
mijj wrote: Tue Jul 30, 2019 8:33 pm How can anyone match a whistle/horn to a loco if one has no knowledge of these things :) .
Jim.
It’s probably only a purist that would notice but I would expect steam whistles from any given operator to be similar.

In my case I believe the Atlantic was an Ivatt design for the GNR, later LNER so I’m assuming that either an LMS or LNER whistle (not an A4 chime) would be close. Hence my comment regarding the Black 5 or J36.

But the Atlantic is referred to as ‘big boiler’ so I’m thinking the J36 may be a bit asthmatic as a stand in. I’d considered the Britannia class as a possibility as it is a larger loco and was designed by Riddles but I believe it shares many characteristics of the Bulleid Pacifics so maybe it’s not ‘northern’ enough for what I want.

As an aside I wonder if Hornby ever thought of doing the TTS as a more generic decoder ie three different decoders to cover 2,3 or 4 cylinders with user selectable whistles instead of some of th3 more gimmicky soundtracks - F4 for GWR, F5 for SR etc?
Hi Steve, like you I have been looking at this as a way to chip more locos for less £!
You have, I think seen my own thread.
Firstly, to answer Jim's point, you can listen to samples of their sound files on some of the chip providers websites.

I don't mean to make your life more difficult, but the other factor I have taken into consideration for steam locos is wheel size.

I was considering using the Britannia TTS for all the 2 cylinder Standard 4-6-0s and 2-6-0s and tanks, except the smaller 78xxx and the 84xxx.
But when I looked at the wheel sizes I realized that the only ones to share the Britannia's 6ft 2 ins wheels were the other Pacifics and the 73xxx 4-6-0s. The others have smaller wheels.
So I am now thinking of using the Black5 TTS (they had 6ft wheels) for all the medium sized Standard 4-6-0s and 2-6-0s and tanks whose wheels are in the range 5ft-5ft 3ins, the Britannia TTS for the 73xxx 4-6-0s, and waiting for a dedicated TTS for the 3 cylinder Duke of Gloucester!
Your 4-4-2 had 6ft 8ins drivers, but only 170lbs boiler pressure so less of a chuff than a Britannia!

I also think you have to take into account what other locos a TTS loco will be heard with. If you can avoid locos that ought to sound different, but you have given the same chip, running together, or one after the other, then you can probably get away with it. At the end of the day if you don't exhibit your layout, provided you are happy with the sound, who cares? And it can be better to have a slightly wrong sound from a loco rather than no sound at all!

I hope the above helps, sorry if it just adds to the confusion?

Best regards
Paul
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Steve M
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Re: Selecting TTS decoders for non TTS locos

#10

Post by Steve M »

I reckon you summed up the challenge perfectly. I was also considering the Britannia and Black 5 TTS as options.
I have posted a couple of short comparison videos on my layout thread.
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