Caber Posted February 16, 2012 Share Posted February 16, 2012 Firstly I would just like to say that I am not bashing the work of the people that make the recordings and such as I think they have done a great job but I do have some questions. I've had a handful of Loksound decoders now, 3.5 and 4.0 with different sound projects on them and different speaker variations but one thing has remained consistent across them all which detracts from the experience and bugs me. On all these different projects there has been very noticeable white noise in the background, more noticeable in the quieter sound operations such as the engine shutting down. Now I'm no audiophile or anything by any means but it is very noticeable for me and I was just wondering what the cause of it is and can it be resolved? is it down to the recording equipment, hardware limitation of the decoders? if anyone else has noticed this could you let me know so I know that I'm not crazy! I'm aware that the sound quality we get in OO gauge is never going to be as good as a proper set of speakers or headphones or whatever. I just feel a little cheated that I have to put up with something like that after spending ~£100 on a decoder + speaker. Link to post Share on other sites More sharing options...
gridwatcher Posted February 16, 2012 Share Posted February 16, 2012 I would experiment with speakers. Biff might want to comment here? The Loksound ones are not the best? DCC Supplies/Alan Butcher/Digitrains have a large selection of alternatives. We have found some of the bass enhanced and bass reflex ones are excellent if you want more ooomph and a less tinny sound. I would say that the newer 4ohm Loksound ones seem better than the old V3.5 100 ohm ones? Getting the back box/speaker back properly sealed is the other key. Some RTR locos have no back box to speak of and the rear of the speaker is totally open. You will never get great sound with these set ups in my opinion. Si Link to post Share on other sites More sharing options...
legomanbiffo Posted February 16, 2012 Share Posted February 16, 2012 Caber, By far and away the biggest contributor to the white noise that annoys you and me both is not the microphone, recording apparatus or editing equipment but the Loksound chip itself. If you play back a clip of pure silence from it you will hear noise, and this is the chip's biggest shortcoming in my opinion. However, there are some very effective work-arounds. Upward facing loudspeakers tend to make the noise much more noticeable and also result in a very thin sound, lacking in bass. Move your speakers to the underframe facing down and you will lose most of the noise and perceive more bass. Also try to use the biggest speaker you can. The standard Loksound speakers have a very lightweight mylar cone and are very good at reproducing high frequencies which make the noise so noticeable. Larger cones made of heavier or higher quality materials are much better. Bass reflex speakers, which tend to 'roll off' more at the high frequency end are also very effective. Also very important is to make your loudspeaker enclosures airtight. Use blu-tac or black Homelux bath sealant from B&Q to fill in any gaps or holes but make sure you don't obstruct movement of the cone. The increase in volume is astonishing to those who haven't tried it. A 30-40% improvement is not unusual. It is an ongoing concern of mine that Hornby and Bachmann continue to produce sound fitted locos that run contrary to this in almost every way. Tiny speakers, facing upwards with small and / or ineffective enclosures that are not properly sealed. It's not rocket science. Link to post Share on other sites More sharing options...
Caber Posted February 16, 2012 Author Share Posted February 16, 2012 Thanks to all of you for your suggestions and insight, I'm glad that it's not just me that notices it so easily. gridwatcher, yeah I have noticed that most of the onboard sound locos have no speaker enclosure at all which is truly shocking. It's the bass enhanced speaker from digitrains that I'm currently using in my class 37 that's producing the noise. Doddy, Thanks for clearing those things up and I'm glad that it's not just me that feels cheated. That new decoder sounds promising but at the same time I worry about the availability of sound projects, makes me wish there were guidelines for the sound decoders that would allow the sound projects to be used on different decoders. That being said, I'm not familiar with the workings of the decoders and if this would even be possible. legomanbiffo, I have not yet had the chance to try my bass reflex in the tanks of my locos as I'm waiting to borrow a dremel from a friend instead of making a hash job of it. So far all of my speakers have been upwards facing, I've tried the standard circle one that come with the decoder and a bass enhanced one under the fans on the v4 decoder. Both of these installation setups produced the same results regarding the background noise so I'm hoping that the reflex in the tanks facing down will be an improvement. I see that you find the cause to be the actual decoder, have you had any experience with the Zimo decoders and how they perform? Link to post Share on other sites More sharing options...
legomanbiffo Posted February 16, 2012 Share Posted February 16, 2012 To say a bass reflex in the tanks of the 37 is an improvement is something of an understatement. I'm just fitting my Metals sector loco with one now - the Alan Butcher version from Digitrains. You have to reduce the depth of it by 2 or 3mm (down to the bevel) and then put a new back on but it's half an hours work for a lifetime of better sound. Just to add to what I said earlier; with a good quality mic and a modern digital recorder there is virtually no noise at all on recordings, not like the old analogue days. Plus it's all edited digitally on the PC so little or no extra noise from there. I have no experience at all of the Zimo chip. Pauliebanger's your man, over to you Paul... Link to post Share on other sites More sharing options...
pauliebanger Posted February 17, 2012 Share Posted February 17, 2012 I am really surprised that you have this problem to the extent that it disturbs you. (I thought with Lok being so much more expensive than Zimo it would be flawless. Ha Ha) I can't say that white noise (hiss?) has ever been a problem for me with Zimo. So following Bif's lead I loaded 'silence' files digitally created in the sound editor to two MX644s and an MX642, and played them at a variety of volume settings. I used the Alan Butcher 40 x 20 mm bass reflex speaker that Bif mentioned above. This is not a very rigorously scientific test. I've only used my ears, no measuring device. I don't have a lok to compare it with. I did not detect any hiss at all from any of the decoders even at value 64 (the theoretical maximum volume before distortion begins) at normal listening distances. By literally putting the speaker to my ears (one at a time obviously) I could just detect a very faint 'background noise' with the 644s and a slightly louder sound from the older 642. It was not a hiss, though, more like a 'mains hum' type of sound. As a matter of interest, my very latest Zimo Multi-Drive sound projects (available from Digitrains) all contain a 'silence' loop as part of the manual notching driving scheme so anyone with one of these will be able to perform the same aural tests. Perhaps the views of several people might reach a concensus. Another possibility for noise with loks, particularly if heard in the quieter samples is that with the resolution being only 8Bit depth, artifacts can be generated in Lokprogrammer when it converts the 44kHz 16Bit to 16kHz 8Bit. These tend to be more of a crackling sound rather than white noise, though. The Zimo programming software does not perform any such conversion. The samples must be in the correct 11 or 22kHz 8Bit format before ZSP will accept them into any project. That means conversion in the editor, but at least that way I can scan the converted files for unwanted artifacts and remove them where possible. Maybe that's where the difference lies. Bif, have you tried loading samples converted in your editor to 16kHz 8Bit into Lokprogrammer? Kind regards, Paul Link to post Share on other sites More sharing options...
pauliebanger Posted February 17, 2012 Share Posted February 17, 2012 Caber, It's notoriously difficult to get a 'clean' sample from sounds ripped from You Tube and MP3s since these files have aleady been subjected to 'lossy' compression techniques. IE, downgraded already. Artifacts can be generated on further conversion simply because the full dynamic range is just not there anymore. Its possible to make good recordings sound bad, but much more difficult, if not impossible, to make a poor recording sound good. So the source of the initial sounds can have a bearing on the final quality. It might pay you to get an assurance from your prefered vendor that their source material is 1st generation, full dynamic range, uncompressed recordings. Kind regards, Paul Link to post Share on other sites More sharing options...
Caber Posted February 17, 2012 Author Share Posted February 17, 2012 Hey paulie, it's not so much that it disturbs me it's just very noticeable and for me just reinforces the feeling of being cheated, but that's just me! I think my original post might have been slightly misleading, I did not mean to imply that I am building my own sound projects and recording sounds off youtube etc. I am talking about the factory Bachmann sounds, I've heard the Bachmann deltic project and the Bachmann class 37 project and the noise was very audible in both. Then again, I could just be overly picky but for the money they charge for these things I expect a quality piece of kit. Thanks for the effort you've gone through to test out the Zimo decoder with silence files, I do appreciate it. I've seen your videos on youtube before and was impressed with the multi drive 37 - I've wanted to try it for some time now, even more so now that you've made some new updates to it! I'll definitely come back and post my thoughts when I get a bass reflex mounted in the fuel tanks. Link to post Share on other sites More sharing options...
M Graff Posted February 17, 2012 Share Posted February 17, 2012 Some sound decoders have no recordings for silence as far as I've seen (earlier Loksound etc.), and that in itself could create white noise..... Silence should be recorded as all other sounds. In regular audio editing you buy different sorts of silence wich you then use. I guess the same applies to sound decoders.....? Sometimes it's just a case of dirty wiring.... I had some static noise in my Loksound equipped switcher, but after moving the speaker cables away from the motor and pick up cables, it disappeared, so I guess it worked. Link to post Share on other sites More sharing options...
pauliebanger Posted February 17, 2012 Share Posted February 17, 2012 I think my original post might have been slightly misleading, I did not mean to imply that I am building my own sound projects and recording sounds off youtube etc. Not at all, I was not suggesting that you were doing this. It was clear from other clues in your post that these were pre-loaded sounds. But you did not say who's sounds they were, so i was tring to give a rounded answer to cover all possibilities. Paul Link to post Share on other sites More sharing options...
edcayton Posted February 17, 2012 Share Posted February 17, 2012 If I can make a simpleton's comment here, whilst I am very impressed with the quality of most diesel sounds (although not the O-gauge Deltic that wasn't), I have yet to be convinced by steamers. On one layout I saw recently the illusion was completely spoiled by thr sounds obviously coming from the tender. Ed Link to post Share on other sites More sharing options...
Nigelcliffe Posted February 17, 2012 Share Posted February 17, 2012 One issue with high frequency hiss is to check the hearing of the person who says they can hear it or that its absent. In general, as people age, their high frequency hearing deminishes quite dramatically. Even aged 45 or 50, the losses are quite striking. And this is before one gets to problems from working in noisy environments or going to too many Status Quo concerts. - Nigel Link to post Share on other sites More sharing options...
pauliebanger Posted February 17, 2012 Share Posted February 17, 2012 One issue with high frequency hiss is to check the hearing of the person who says they can hear it or that its absent. In general, as people age, their high frequency hearing deminishes quite dramatically. Even aged 45 or 50, the losses are quite striking. And this is before one gets to problems from working in noisy environments or going to too many Status Quo concerts. - Nigel Pardon, what was that you said just then, young Nigel? Ha ha For me it was the 'Stones and Saxon. Paul Link to post Share on other sites More sharing options...
legomanbiffo Posted February 17, 2012 Share Posted February 17, 2012 And for me, it was The Stranglers at the Glasgow Carling Academy! Loved every minute of it though. Link to post Share on other sites More sharing options...
gridwatcher Posted February 18, 2012 Share Posted February 18, 2012 Ah Biff. We never got to music. At Glasgow Modelrail two years ago we went to the Wetherspoons straight after the show (just down from Glas Central, The Glasshouse?) Thought it was really weird that the place was full of 40 something blokes, virtually no women and everyone was wearing black.......yes you guessed, Stranglers at the Academy. My I only saw them once way back in 79?on The Raven tour. Very good they were too. Link to post Share on other sites More sharing options...
Lady_Ava_Hay Posted February 18, 2012 Share Posted February 18, 2012 For me it was Pink Floyd at Earls Court in 1980. i actually think my hearing may have been more damaged by shotguns. I was a keen shot at one time. As to Doddy;s post the only issue is obtaining sound files in 'the highest quality you can get' but avoid MP3 and aim for CD quality WAV files. i always work on mine in that CD quality and then save the worked files in the Loksound format keeping the originals in CD quality.If you need to change the format it is as well to start again or remember to save in all formats that you might use. The biggest bugbear of field recording ( and even Bachmann have to do that ) is the background noise like rain on plastic or sheep baaing or even a dog barking. Ok at first but a bit wearing after the umpteenth play. Link to post Share on other sites More sharing options...
kevpeo Posted February 18, 2012 Share Posted February 18, 2012 And in my case yesterday when trying to record 37 423, the bog door slamming! I too saw The Stranglers on the '79 Raven tour, Lancaster University, my first gig! kev. Link to post Share on other sites More sharing options...
pauliebanger Posted February 19, 2012 Share Posted February 19, 2012 It seems my ears might be working OK after all. Just read a post on another forum basically saying that the Zimo MX648 chip he has is both louder and cleaner sound than Lok micro, no white noise. His exact words were (about the Zimo) 'in fact, I'm utterly astounded at the quality....' Oh dear. Still, if you use your loks up in kettles you won't notice it so much! Ha ha. (only jesting) Paul Link to post Share on other sites More sharing options...
status quo Posted February 19, 2012 Share Posted February 19, 2012 Hi Guys Well after being at 26 Status Quo concerts I think my ears are ok. Zimo to me, is the best sound i have ever heard. Possibly better than the quo. lol. Steve Link to post Share on other sites More sharing options...
Lady_Ava_Hay Posted February 20, 2012 Share Posted February 20, 2012 Gentlemen, Please, we have been this route a thousand times to no profit. Any more 'this sound decoder is better than that sound decoder for sound quality' will result in the thread being locked. Link to post Share on other sites More sharing options...
TheEngineShed Posted March 21, 2012 Share Posted March 21, 2012 I have yet to be convinced by steamers. On one layout I saw recently the illusion was completely spoiled by thr sounds obviously coming from the tender. Not certain what the solution is if you can't use the tender. I don't know that I have experienced this, I wonder if it might have been because the speaker was pointed up, through the coal load, and you were quite close? Short of backing the tender into a shed, or some other obstruction, I find it darn hard to localize the sound source from a kettle in the open from normal viewing distances... Please, we have been this route a thousand times to no profit. Any more 'this sound decoder is better than that sound decoder for sound quality' will result in the thread being locked. Well, problem is that some decoders are better than others. 16 bit sound decoders do sound better than 8 bit, but you get what you pay for. Some of the 16 bit decoders do have more features than others which gives you a bit more flexibility. And not all sound projects are equal... I'd agree though, if you say one is better than another, you should try to explain why you think that is so. Link to post Share on other sites More sharing options...
pauliebanger Posted March 21, 2012 Share Posted March 21, 2012 Well, problem is that some decoders are better than others. 16 bit sound decoders do sound better than 8 bit, but you get what you pay for. Some of the 16 bit decoders do have more features than others which gives you a bit more flexibility. And not all sound projects are equal... I'd agree though, if you say one is better than another, you should try to explain why you think that is so. I agree, what you say is correct. There are differences in quality and features in both decoders and sound projects, it's wrong to pretend otherwise. How to express those differences without upsetting people is a real dilema. Sound is not subjective, there is plenty of science to support that. How we each perceive sound, however, is both subjective and changeable. It's difficult to comment on 'quality', which was the OPs reason for posting, without using comparisons. Even if we published empirical data it's unlikely that the majority would understand its significance, so the best that we can achieve is to compare one with another. Are there any 16 bit fully programmable decoders available yet? Some assertions can be justified by factual explanations, others will be expressions of a personal view. The former can be supported by reference to source material, the latter need to be obvious to the reader that these are the posters' opinions. Kind regards, Paul Link to post Share on other sites More sharing options...
Etched Pixels Posted March 22, 2012 Share Posted March 22, 2012 Agreed - if you want to actually figure it out then you need to measure them all properly. Subjectively to me the Digitrax is underwhelming and certainly hisses a lot. The Zimo and CT both have good quality digital amps and seem very quiet. My one Loksound 4 fitted unit isn't that clean a sound but I'm not sure if its the samples or the chip. Other factors though are the speaker, recording quality and also the volume range the chip can provide. In N for example any hiss tends to be quite noticeable because you are using small speakers so tending to get rather more high than low end and already rebalancing the audio to try and cut down on the high end volume. Link to post Share on other sites More sharing options...
Poe Posted March 23, 2012 Share Posted March 23, 2012 Buy a tascam dr-40 for recording best thing i ever did. Link to post Share on other sites More sharing options...
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