unable to convert mp3 file to different frequency

[bradsayers]

I have dbpoweramp with the powerpack.

All I need to do is convert an existing mp3 file which is at 11 khz to 32 khz (32000) MP3 lame. I have a created labs zen xtra jukebox and that is the only frequency that won't play properly so I need to change it.

However, when converting I am only getting an error message that "file can not be opened" and it will not convert. I have tried several other frequencies but get the same error.

I can convert from mp3 to wave with no problem. If I choose test conversion I get the same error message.

Is there anything I need to do differently? I have redownloaded converter

TIA Brad

[ChristinaS]

Re: unable to convert mp3 file to different frequency

I can convert from mp3 to wave with no problem. If I choose test conversion I get the same error message.

Do you mean you can convert that particular mp3 file to wav with no problems but cannot do a test conversion of it? That's very curious. Please try again, as you may have been mistaken.

In any case make sure you don't have the file opened in a player while you try to perform the conversion. Also don't instruct dMC to delete the original file and don't direct the output to the same folder, since the resulting file will by necessity have the same name as the original file and it cannot replace it while it's being used.

[LtData]

Re: unable to convert mp3 file to different frequency

Try the latest dMC beta linked to below.

[xoas]

Re: unable to convert mp3 file to different frequency

First, read Christina's precautions against not replacing the source file with your new file and not ovewriting to the same folder (unless you rename the file).

If it does not work, try LtData's suggestion for trying the latest dMC beta version (the mp3 decoder is improved over the mp3 decoder for the standard version of dMC).

If those tips do not work, as you can convert your mp3 file to wave, what are the settings for the wave file (bits, frequency, channels)? Have you tried converting the wave file to mp3 at 32 kHz? If that works, do it.

If that still does not work, can you tell us the bits, channels and bitrate for the original mp3 file and the bitrate and channels for the 32kHz mp3 you are trying to create?

Best wishes,
Bill

[LtData]

Re: unable to convert mp3 file to different frequency

After installing the dMC beta, try converting your mp3 file to a 11KHz WAV file and then to a 33KHz WAV file and then to a 33KHz mp3 file. Sometimes, changing the frequency and converting to mp3 at the same time can cause errors.

[bradsayers]

Re: unable to convert mp3 file to different frequency

Thanks to all for your suggestions, following are the results:

>>>Do you mean you can convert that particular mp3 file to wav with no problems but cannot do a test conversion of it?

YES

>>>In any case make sure you don't have the file opened in a player while you try to perform the conversion. Also don't instruct dMC to delete the original file and don't direct the output to the same folder...<<<

File was not in use and I was not retaining the same file name.


>>>...try the latest dMC beta version....After installing the dMC beta, try converting your mp3 file to a 11KHz WAV file and then to a 33KHz WAV file and then to a 33KHz mp3 file. Sometimes, changing the frequency and converting to mp3 at the same time can cause errors.<<<


I installed the beta version and here are the findings:

I was able to convert an 8 mb mp3 (11000hz) to mp3 at 32000hz. It took 8 minutes and it became 232 mb in size - huge!!!

The other suggestion: I was able to convert the 8 mb mp3 (11000hz) file in question to a wave file (16 bit; 11000 Hz; 2 Stereo (CD). This 8 mb file becomes 80 mb (takes about 20 seconds to convert). To then convert this new wave file to frequency 32000 takes 3 1/2 minutes but the file bloats up to 232 mb. I could then convert this huge file to mp3 (at 32000hz) which took 4 minutes and shrinks it to 29 mb.

So - the multi-step process works but is that the only way to take an mp3 file at one frequency to convert it to another of practical size? The direct conversion makes a huge file - too huge to practically use.

Brad

[ChristinaS]

Re: unable to convert mp3 file to different frequency

I find that extremely hard to believe a conversion using Test Convert (no write) doesn't work but conversion to a specific format does. Test Convert simply reads the file, so it's one half of any conversion. This anomaly indicates a major corruption somewhere.


It's weird, a change of frequency hardly changes the file size. It's only the bitrate and the number of channels that will do it.

What are all the specs you have for your input file and what did you select for the output ?

Please state the file size, duration, bitrate, channels, frequency of your input mp3 file and what you selected for your output files - and what you got for each step.

[bradsayers]

Re: unable to convert mp3 file to different frequency

Hi Christina,

The test convert failed with the previous version not the beta which worked fine. And in the previous version it really did convert the file but failed the test convert. I tried this on several files. I was really trying to get it to work since I have about 75 files to change from 11000 hz to get to work on the zen xtra (this is a known issue btw).

Here are the details of the file I am working with: file size, 7246 kb; bitrate 32; frequency 11025; channels 1(mono).

I right click on the file and choose convert t: choose MP3 (Lame), channels stereo, frequency 32000 hz. The min bit rate is 128 and the max is 256kbps. I don't change anything else. Choose convert and I get those file sizes and times I mentioned in previous post.

I hope this information will help, let me know if you need more detail. Brad

[ChristinaS]

Re: unable to convert mp3 file to different frequency

Hi Christina,

The test convert failed with the previous version not the beta which worked fine. And in the previous version it really did convert the file but failed the test convert. I tried this on several files. I was really trying to get it to work since I have about 75 files to change from 11000 hz to get to work on the zen xtra (this is a known issue btw).

Here are the details of the file I am working with: file size, 7246 kb; bitrate 32; frequency 11025; channels 1(mono).

I right click on the file and choose convert t: choose MP3 (Lame), channels stereo, frequency 32000 hz. The min bit rate is 128 and the max is 256kbps. I don't change anything else. Choose convert and I get those file sizes and times I mentioned in previous post.

I hope this information will help, let me know if you need more detail. Brad

Ok, upon converting you are changing lots of other parameters not just the frequency. Stereo doubles the file size over mono. You opted for a variable bitrate a lot higher than the original 32kbps, by a factor of 4 to 8. Therefore this will multiply by a factor of 4 to 8 the resulting file size again. So it's no small wonder that you are ending up with a file size from 8 to 16 times bigger than what you started out with. You had about 7MB at first, so this will be between 56MB and 112MB easily. Not sure why you got 232MB though (is my arithmetic wrong?) .... but once there's a bug, there may be many others.

Ok, so now you have the beta version which works fine.

Do the conversion again and don't use any presets on the output mp3. Rather control that manually. Click Advanced Options and select No preset for Quality, and Constant bitrate. Back on the previous window, set channels as mono, frequency as 32000 and bring the bitrate slider to 32kbps. This should convert your file properly. The final file size should be maybe just a bit larger than what you started out with.

[xoas]

Re: unable to convert mp3 file to different frequency

Brad-
Check dMC Configuration (Start>All Programs>dBpowerAMP Music Converter>Configuration>dBpowerAMP Music Converter configuration).
Check to see whether you have Professional Frequency Conversion enabled. If it is not enabled, please enable it. This feature is for just the type of situation you are looking at, trying to convert files from one frequency to another.

Try again a direct mp3 to mp3 conversion with the dMC beta with Professional Frequency Conversion enabled and using Christina's suggestions above. You prior experience suggests some type of problem. I note that your 32 kHz mp3 was supposedly the same size as your 32 kHz wave file. I will have to check but ordinarily there is no way that a wave file will not be at least 3 to 4 times larger than an mp3 file of the same track, even with mp3 encoded at its highest setting. If this continues to be the case, please let us know.

I think with Professional Frequency Conversion enabled you should be able to do the conversion directly. If not, I am betting that you should be able to get by with only one intermediate conversion (most likely from mp3 to wave at 11025 Hz, 2 channels or to 32 kHz, 2 channels; then from wave to mp3 at 32 kHz, 128 kbs, 2 channels).

Best wishes,
Bill

[ChristinaS]

Re: unable to convert mp3 file to different frequency

The standard uncompresed PCM wav (16-bit, 44.1KHz, mono) corresponding to that 7 MB, 32kbps mono mp3 file would be about 40 times larger at about 280MB. As I said the frequency doesn't affect much the size, but the bitrate does in direct proportion. At 128kbps it would be about 4 times bigger than the 32kbps mp3, or 28MB.

[bradsayers]

Re: unable to convert mp3 file to different frequency

The option "Professional Frequency Conversion" had been enabled (default install I believe)

Following Christina's points, the 8 mb file took 3 mins to convert and size and ended up virtually the same as it was. I see that the frequency has changed to 32000 and I put in on my zen xtra and was happy to hear that all is sounding as it should. (a file at 11,000 sounds like slow motion if played on the jukebox - the only frequency that doesn't work - which is why I am using dbpoweramp!).

Anyways, thanks to Christina and the rest of the gang there. I am going to be reading spooners guide today to get me more up to speed on all this. Any other suggestions for a newbie and mp3 files / conversions etc?

Thanks so much Brad

[ChristinaS]

Re: unable to convert mp3 file to different frequency

Glad to hear it's sorted.

My advice? Don't use on presets for quality settings, they make you oblivious of what is actually going on. I think presets are fine only once you really know what you are doing, not before.