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Digitrax decoder sound quality

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Digitrax decoder sound quality
Posted by 2002p51 on Tuesday, January 7, 2020 1:01 PM

I recently installed a Digitrax SDXH166D sound decoder into a Life Like Proto 200 GP9. The unit runs fine, slow speed is smooth and the horn and the bell sound good. But the prime mover sound is barely audible. I have CV 58 set to factory spec and I've adjusted the prime mover volume CV all over the range with no change. It is unsatisfactory. I was just wondering if any of you have had a similar problem with Digitrax decoders and if this is a common problem or what? 

 

Tags: decoder , Digitrax
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Posted by rrinker on Tuesday, January 7, 2020 2:07 PM

 WHat sound file did you load? SOme are better than others - some take advantage of the extra features the X version of the decoder has over the same one without the X in the nane, others are universla nd can work in any of the decoders, which means at most they can use only the feautures of the older decoders.

 All in all, you basically get what you pay for, a low cost soudn decoder isn't going to be as good as one of the top tier ones like Loksound, Tsunami 2, or WowSound.

 ALso, you may have to turn down the horn and bell, crank the prime mover, crank the master volume, and then adjust the horn and bell.

                           --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by 2002p51 on Tuesday, January 7, 2020 2:56 PM

I tried both the GP10 and GP38 that are in the decoder. And trust me, I've had those volume CVs all over the place. 

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Posted by wjstix on Tuesday, January 7, 2020 3:40 PM

In my experience, the Digitrax decoders have good sound but lacking a bit in power. A really good speaker and enclosure are vital - if possible, a 1" speaker is best.

But as noted, different sound projects have different properties. With some you can get away with a smaller speaker like 1/2" x 1". I'd check out all that are available - IIRC there are several F-unit projects available, their sounds should work for a 1st generation GP.

Stix
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Posted by mbinsewi on Tuesday, January 7, 2020 3:47 PM

wjstix
A really good speaker and enclosure are vital - if possible, a 1" speaker is best.

I'll remember that, I'm thinking of a Digitrax sound decoder for my F7 a-b powered passenger train, for the economics.  This would be my first sound install.

Mike.

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Posted by BigDaddy on Tuesday, January 7, 2020 3:49 PM

What speaker did you use?

Henry

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Posted by 2002p51 on Tuesday, January 7, 2020 7:00 PM

BigDaddy

What speaker did you use? 

 

The speaker that is hard wired to the decoder. It's an oval 16 x 26 mm and has a built in hard plastic baffle.

 

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Posted by BigDaddy on Tuesday, January 7, 2020 7:15 PM

2002p51
The speaker that is hard wired to the decoder. It's an oval 16 x 26 mm and has a built in hard plastic baffle.

I didn't know it came with a speaker.  In a recent video, Larry Puckett had a negative comment on oval speakers.  I have no personal experience on ovals.  One thing I did learn, which isn't your problem, is that at least some TCS decoders can overpower and blow out a sugarcube speaker.

Henry

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Posted by mbinsewi on Tuesday, January 7, 2020 8:14 PM

Here's the decoder and speaker.

http://www.digitrax.com/products/sound-decoders/sdxh166d/

Thinking of this one myself.  Half the price of a WowSound, but, you get what you pay for.

Mike.

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Posted by 2002p51 on Wednesday, January 8, 2020 3:59 AM

mbinsewi

Thinking of this one myself.  Half the price of a WowSound, but, you get what you pay for.

Mike. 

 

I get that. I bought this one from an on-line retailer so I didn't pay the MSRP listed but it wasn't what I would consider cheap either. I'm late to the party when it comes to getting into DCC and converting my DC locomotives has certainly been a disappointing experience so far.

 

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Posted by richhotrain on Wednesday, January 8, 2020 6:18 AM

I don't have the Digitrax SDXH166D in any of my locos, but I did spend all weekend adjusting the various volume controls on my locos that are equpped with Tsunami or QSI. So, let me offer my most recent experience.

First of all, while the Digitrax sound decoder may be less expensive than other sound decoders, I would initially proceed on the assumption that the cost factor should make no difference as far as volume is concerned.

Second of all, I would initially proceed on the assumption that the speaker is not defective. Maybe that will turn out to be the problem, but for testing purposes, assume that the speaker is just fine. That said, the decoder instruction sheet does note on page 4 that the speaker mounting and baffle can greatly affect sound performance.

Third of all, regarding sound files, although that decoder offers 7 different choices, the factory default is set to zero so the Sound Scheme Select (CV 60) has been disabled, resulting in generic sound.

In testing my locos over the weekend, I had pencil and paper at hand to note the various CV settings that I was testing since the various volume controls are somewhat interrelated. Begin testing with a decoder reset to factory defaults (CV 8 = 8).

Then start with the Master Volume control (CV 58). The factory default is 9 over a zero to 15 range. So, the maximum volume of other controls is limited to 60% of the maximum capacity. Change the setting to CV 58 = 15. Reset the bell (CV 141) and horn (CV 142) to zero to mute those sounds. Now, start adjusting the Prime Mover volume control (CV 140) with a very low value, say 5. The factory default is 60 within a range of zero to 64.  Test the sound volume at CV 140 = 5. Then, reset the sound volume at CV 140 = 60, the factory default. The prime mover volume should be significantly louder.

Let us know if that works.

Rich

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Posted by 2002p51 on Wednesday, January 8, 2020 8:52 AM

Rich, 

All good information, thank you. I would think if the speaker were the problem, or it were damaged, it would affect the bell and horn too. Those sound fine.

I sent a message to the Digitrax "Help Desk" and part of their response was: "The prime mover in this sound file is relatively quiet."

To which I would replay; Who wants a "relatively quiet" locomotive?

They also suggested that I set CV60 to 3, which is the GP10 sound file, and set CV 140 to 64, which is the max. I did both and it made no difference. 

The bottom line here?  I will never buy another Digitrax decoder.

 

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Posted by richhotrain on Wednesday, January 8, 2020 9:02 AM

Have you checked the value of CV 58 which is the Master Volume control?

If all else fails, why not email the Digitrax Help Desk again and tell them that you did what they suggested but that the PM volume is still barely audible?

Rich

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Posted by rrinker on Wednesday, January 8, 2020 9:06 AM

 Try another sound file, one that actually uses the capabilities of the X series. Those built in ones (3 of them - consider the GOOD projects use all the memory for ONE loco). Look for one that explicitly says 16 bit, and particularly ones made by John McMasters. The GP38 and GP10 schemes that come with the decoder are 8 bit, not 16 bit, and are of much lower quality than the decoder is capable of. They are included so you don't get a blank decoder with no sounds and wonder if it is DOA.

 IN general, the horn SHOULD be louder than the prime mover. A weak horn quieter than the prime mover no matter what you do is why I got rid of the one Tsunami I tried and never bought another. The first Tsunami 2's didn;t sound any better, but more recent ones, it seems liek maybe they have updated the recordings a bit. Too late, I'm strictly ESU now. 

                                                    --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by mbinsewi on Wednesday, January 8, 2020 9:42 AM

rrinker
Look for one that explicitly says 16 bit, and particularly ones made by John McMasters.

Thanks.  Found one for the F7.

Not hijacking OP, just riding along. Smile, Wink & Grin

Mike.

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Posted by 2002p51 on Wednesday, January 8, 2020 10:26 AM

richhotrain

Have you checked the value of CV 58 which is the Master Volume control?

If all else fails, why not email the Digitrax Help Desk again and tell them that you did what they suggested but that the PM volume is still barely audible?

Rick 

 

Yes, Digitrax suggests a value of 4 or 5 and i've tried it there and every where up to the max 15. No result.

As for replying to Digitrax again, not sure it would do any good. I got the impression from their firstanswer that this is working as it was supposed to.

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Posted by 2002p51 on Wednesday, January 8, 2020 10:29 AM

rrinker

 Try another sound file, one that actually uses the capabilities of the X series. Those built in ones (3 of them - consider the GOOD projects use all the memory for ONE loco). Look for one that explicitly says 16 bit, and particularly ones made by John McMasters. 

 

And where do I find that and how to I get it into the decoder?

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Posted by richhotrain on Wednesday, January 8, 2020 10:36 AM

2002p51
 
richhotrain

Have you checked the value of CV 58 which is the Master Volume control?

If all else fails, why not email the Digitrax Help Desk again and tell them that you did what they suggested but that the PM volume is still barely audible?

Rick  

Yes, Digitrax suggests a value of 4 or 5 and i've tried it there and every where up to the max 15. No result.

As for replying to Digitrax again, not sure it would do any good. I got the impression from their firstanswer that this is working as it was supposed to. 

Well, I guess that there is not much more to say at this point. If the prime mover is barely audible, and Digitrax thinks that is as it should be, dunno.

Rich

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Posted by rrinker on Wednesday, January 8, 2020 10:39 AM

In the Sound Depot on the Digitrax web site. You need a PR3 or PR4, and the Soundloader software to load sound files. Most vendors will load your choice before shipping the decoder, otherwise you will need to find someone with the proper hardware.

 Most of them listed have sound clips to play so you can hear what they sound like.

                                --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by richhotrain on Wednesday, January 8, 2020 10:53 AM

rrinker

The GP38 and GP10 schemes that come with the decoder are 8 bit, not 16 bit, and are of much lower quality than the decoder is capable of. 

I'm strictly ESU now.  

I just watched a YouTube video in which an Atlas employee demonstrated a GP38 with an ESU sound decoder. That prime mover was awfully loud. No idea what Digitrax may be thinking.

Rich

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Posted by willy6 on Wednesday, January 8, 2020 11:16 AM

Years ago I put a Digitrax 166 decoder in an Athearn RTR locomotive (HO). I had the same low volume prime mover problem. I did learn this was a problem with this decoder. I can't remember if I found out about this problem on these forums or another source but after changing settings here and there the results never changed. 

Being old is when you didn't loose it, it's that you just can't remember where you put it.
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Posted by 2002p51 on Wednesday, January 8, 2020 11:28 AM

richhotrain
 

I just watched a YouTube video in which an Atlas employee demonstrated a GP38 with an ESU sound decoder. That prime mover was awfully loud. No idea what Digitrax may be thinking.

 

Rich 

 

Exactly Rich. I could run this thing through a library and nobody would notice. 

I have a pair of Athearn Genesis GP9s and they sound great just like a locomotive should.

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Posted by mbinsewi on Wednesday, January 8, 2020 11:47 AM

Well, this is my first sound install, so I'm going to try it with the 16 bit file that Randy mentioned.  I can get the decoder from my LHS for $60.

I have the PR4 and the program.

I don't have the ESU programmer, and picking the ESU decoder I need seams a bit confusing, so I'll try this first to get some experience in sound installs.

Thanks for letting me ride along, 2002p51.

Mike.

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Posted by ba&prr on Wednesday, January 8, 2020 10:02 PM

This should be a better sound file. You will need a PR3 or 4 to load the files. It can also be used with JMRI.   Joe

http://www.digitrax.com/sound-depot/emd-567c-16-f9ph-non-turbo-roots-1500hp/

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Posted by rrinker on Thursday, January 9, 2020 7:38 AM

 The speaker can make a big difference as well. Is there an enclosure? Is there a path for the sound to get out once the shell is on?

I've seen people say that the old Sound Bug is really low volume. When I got mine, I hooked it up on my bench, and just laid the speaker down, no box around it. GF was in the next room watching TV and heard it when I tested it, just by cupping my hands around the speaker. The SD38 that came on that is I'm pretty sure the same one that's built in to the newer decoder. 

 The better files have the prime mover mixed louder. This is all the same as audio recordings in geeneral - maybe on the original studio album, the mix was such that you could hardly hear the bass among the other instruments. But then someone takes those same masters and remixes it, and now the bass is loud and clear.

 They should have had someone more expert in this set up the initial ones they supplied when the decoders were introduced, they may have gotten a better response. Far as I know, only two people have ever explored what you really can do with these decoders - like many of his designs, AJ left a lot for the user to discover on their own. John McMaster did a lot, and Fred Miller is another one who actually wrote a program to make it easier to create your own sounds. Of course, the average hobbyist doesn;t have the access to go out and put mics all over a locomotive and have the railroad run it through all 8 notches and do a load test on it to capture said sounds. Evidence, how few options there are in the Sound Depot vs how many different ones (hundreds) there are for Loksound decoders - Loksound actively goes out and gets recordings of locos to create new and/or update older sound sets.

                                             --Randy


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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