How to fix poor TTS pronunciation - Discussion

Hello -

I just received my new TomTom XXL 540 TM a couple of days ago. Generally, I am pleased with this GPS, however compared to my Garmin Nuvi 650, the TTS pronunciation leaves a lot to be desired. As suggested in post #1 of this thread, I located the "cphoneme.dat" file and attempted to do a simple rename to "cphoneme.old".

With the disconnected GPS, I turned it ON and heard a strange bongo sound at startup. Then when I entered a legitimate Navigate To... address from my current location, I heard no TTS instructions from the computer voice, Simon.

I then reconnected my GPS to my computer and attempted to rename "cphoneme.old" back to "cphoneme.dat" and found that the filename had been changed to "cphoneme.old.dat". When I tried to rename that to "cphoneme.dat", it actually was changed to "cphoneme.dat.dat".

I have fixed the filename back to the original "cphoneme.dat", but I'm confused by the rename problem and why it happened. I suppose I will create a new file named "cphoneme.old" and copy "cphoneme.dat" to it and then delete "cphoneme.dat" and see if that works.

Any ideas on what I did wrong?

First of all, in Control Panel-->Folder Options-->View-->advanced, make sure you have 'hide extension for known files types UNCHECKED'.

Now then, when you rename the file cphoneme.dat to cphoneme.old, there should be a box to select 'all files' when you do the save. That should get rid of the extra extension.

In truth though, even winding up calling it cphoneme.dat.old accomplishes the same thing in that the application won't see a cphoneneme.dat file to call upon.
... In truth though, even winding up calling it cphoneme.dat.old accomplishes the same thing in that the application won't see a cphoneneme.dat file to call upon.
Well, that's what I thought, too. It sure seemed to produce a couple of strange things to occur though.

I will follow your instructions and go back and try again. Thanks.
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Thank you for the work you've done on this. I've just received my XXL 540M and have made the changes. I live near Saint Johnsbury, VT commonly abbreviated St Johnsbury. The TTS says 'Street Johnsbury' but that's close enough! marty
From what I've learned on this forum, I think if you open the LoquendoTTS folder, then open the Data folder, then click on the roadnrEnglishUS.lex file, you can enter any word/phrase to be pronouned the way you would like. If it says, "Street Johnsbury" it's because Tom Tom has it abbreviated as "St Johnsbury" as you said, and is taking each word separately. Try adding a line, "St Johnsbury" = "Saint Johnsbury" and see if that corrects it. If not, you may have to add the "." after "St" to get it to work. Also, if you set it to, "Saint, Johnsbury" (with a comma, it will take a slightly longer pause between the words (sometimes TT garbles the longer words). Try it and let us know. To be safe, copy the ".lex" file you are changing to a "'txt" file just in case. This worked on a pronunciation of "Thomas E Dewey thruway" which i couldn't understand until I changed it.
Hi all.

I am a new XL 340 S LIVE owner. Overall I'm pretty impressed!

I notice the TTS sounds as if sometimes the computer lady has marbles in her mouth. Especially when she says "Avenue". Is this what you guys are referring too? Will this get fixed if I do the procedure in this thread?

How do I get the "ou/ow" sound as in "ouch" and "cow"? I've been able to edit a few other place names sucessfully, but this one I can't figure out.
How do I get the "ou/ow" sound as in "ouch" and "cow"? I've been able to edit a few other place names sucessfully, but this one I can't figure out.
It's actually two sounds (dipthong), when you think about it. Here are a couple of pairs. Give them a try and see which you prefer:

oa u (or oa U for a bit of a different sound)
Ah u (or Ah U)

Using the U instead of the u seems to give mine a strange Minnesota kind of twist <g>

There are a great many sounds in English that must be composed using multiple sounds. I remember back "in the day" when speech synthesizers were first being brought to market for computers... and the fun we had trying to create normal sounding speech from bits and pieces.
Does anyone know my XXL 540 TM will pronounce "H-O-V" (used for high occupancy vehicle) lanes? Until I modified the appropriate file, my Garmins used to pronounce it phonetically as "hov".
I am still having trouble with my go740live
Here for the road Montgomery Dr, it reads Montgomery Doctor???
I 95 NB read NB instead of Northbound(same thing for SB, EB, WB)
(ops nevermind)
The navigation read the name correctly. It is the traffic part that pronounce it wrong
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I updated my maps to the new 855. I had to do this again.

To fix TTS, go to your map folder (usually "North America" or "Usa_Canada_and_Mexico") and look for the file cphoneme.dat. Rename this file cphoneme.old.

I guess I will have to do this with every map update.
Until they fix the code for pronunciation properly, I'm afraid so.

Another reason for Explorer backups! :D
I have discover one more question
Is it possible for tomtom to seperate st(saint) and st(street)?
I was going something called St. Davids (Saint Davids) and tomtom pronounce it Street Davids
so is there a way to correct it?
On XXL 550 removing cphoneme.dat will cause wrong pronunciations:

sw will say software and some street names sound wrong.
Follow up question

Do you mean if we change cphoneme.dat to cphoneme.old it will also cause pronunciation problems, or just by removing cphoneme.dat altogether?
I have noticed that my voice "Susan" on the XXL 540 pronounces New York City as "NY City." Is there a way to fix this so the voice says "New York"? There are many other pronunciation glitches like this one too.
Renaming as the same effect as removing it.

So, rename it to cphoneme.old and observe whether the positives are better than new negatives compared with the previous sounding of words.
Is there a way to instantly test your changes to the English.lex file? In other words, just type in the place name and Susan immediately speaks this word. As things are now, I have to create a route where I know the place name will be used, then go into demo mode. This would speed up the process from minutes to seconds.

Also, the voices don't seem to work when connected to my home computer. That would save a little time as well.
That's correct, computer voices aren't available in the emulator.

I don't know of any way to test the speech other than via the demo process.

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