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NoOne
07-16-2005, 09:20 PM
When converting some FLAC files to MP3 there seems to be too much bass in the resulting MP3's and it sounds very distorted. It seems to be only with 1 album that I have tried. There is no ReplyGain information for these files so I'm wondering what is causing this. Any ideas?

Thanks in advance.

LtData
07-16-2005, 09:44 PM
Are you running any DSP effects on these files?
What is the frequency and channels of your source FLAC file?
What is the frequency and bitrate of your mp3 file?

NoOne
07-16-2005, 10:59 PM
I'm not running any DSP effects and I don't see any in the the Music Converter, where would that be? The FLAC files are 44.1k stereo and the MP3's are the same.

LtData
07-16-2005, 11:04 PM
DSP effects are found on the window where you choose your codec and destination directory. It is a "PowerPack DSP" button. Make sure the left column is empty.
What is the bitrate of the outputted mp3 files?

ChristinaS
07-16-2005, 11:08 PM
DSP effects are available through the DSP button you see in the windows for dMC once it offers you a choice of codecs. Click on that and see if there's no DSP effect already enabled. You will have that as long as you have the POwerpack - and you must have it since you can convert to mp3.


But also make sure you are not using any preset equalizer when you play back those mp3's.

Depending on the bitrate you are converting to it's possible certain frequency ranges either get lowered or emphasized as well.

NoOne
07-16-2005, 11:51 PM
Ohh haha I forgot about that DSP button. It was right in front of my face there. Anyways there are no DSP effects selected. I want the outputted MP3 files at 320Kbps. I also tried it 2 more times with the same results.

When I played them back, I played both an MP3 and a FLAC file one after another to compare. Both with an equalizer setting and without. Same result (although obviously with the EQ on it was much more noticeable).

EDIT: I just tried 1 track with a lower MP3 bitrate (192kbps) and still the same problem. :(

ChristinaS
07-17-2005, 03:59 AM
Convert a flac file to standard PCM wav, 44.1KHz, 16-bit, 2-channel stereo.

How does that sound?

Next convert the wav to mp3.

NoOne
07-18-2005, 11:43 PM
Ok, the wav sounded fine, but when I converted the wav to MP3 it happend again.

So basicly I assumed it's a problem with the MP3 decoding in dbpoweramp (corrupted file or something?). So I tried other programs, CDex and Winamp.

Same problem with both of these. I'm stumped.

GSV3MiaC
07-19-2005, 09:11 AM
Ok, the wav sounded fine, but when I converted the wav to MP3 it happend again.

So basicly I assumed it's a problem with the MP3 decoding in dbpoweramp (corrupted file or something?). So I tried other programs, CDex and Winamp.

Same problem with both of these. I'm stumped.

iirc all those programs are using the same (LAME) MP3 encoder to generate the MP3. You could try some different encoding options, or you could try the FhG
codec to see if that does any better. Or you could just face up to the fact that MP3 is past it's "use by" date, and pick a better lossy encoding system.

ChristinaS
07-19-2005, 12:03 PM
Are you using headphones or speakers on your pc to listen to your mp3?

I am asking because my soundcard is acting up and some audio files sound bad when played through the speakers but good when played through the headphones. I haven't bothered to try to figure out exactly what it is that's doing this - I ordered a new soundcard instead :p

xoas
07-19-2005, 12:21 PM
I wonder whether it makes any difference if you encode to Alt Preset Insane vs. No Preset, 320 kbs, constant bitrate (cbr)? You might try this to see if it makes a difference. While Alt Preset Insane is supposed to be 320 kbs, cbr, it may have other tweaks of other variables which might affect the sound for better or for worse.

Best wishes,
Bill

NoOne
07-19-2005, 07:52 PM
GSV3MiaC, The other programs do indeed use the LAME encoder but they both have their own encoders built in.
I cannot use a different lossy encoder as my collection needs to be portable and support different devices.

ChristinaS, I do listen to my music on my computer through headphones as well as speakers and I know its not a problem with my soundcard as this problem only happens with these files.

xoas, there are some minor tweaks between Alt Preset Insane vs. No Preset, 320kbps cbr but the changes are so minor that it's indistinguishable. And I have tried both.

LtData
07-19-2005, 08:22 PM
Have you mabye tried the Blade mp3 encoder? It is supposed to be best at high bitrates. Mabye see if it gives you the same results?

NoOne
07-19-2005, 10:33 PM
I don't think I want to use an encoder that is no longer being developed/supported (http://bladeenc.mp3.no/). Thanks though.

Spoon
07-20-2005, 02:48 PM
Blade is pretty old, Lame out performs it at all bitrates. Try this:

Encode your FLAC to wave and look at it in a wave editing program (SoundEngine is a free one). Then encode to lame, then encode that lame to wave and have a look in soundengine. It will be obvious if the volume has increased looking at the wave form, play both wave files inside sound engine.

LtData
07-20-2005, 05:40 PM
The reason I suggested blade was to see if it was a setting your player had for mp3 files, or the LAME encoder itself.
I assume you have also tried a different program to play your mp3s?

NoOne
07-21-2005, 07:05 PM
Spoon, I tried what you said in Nero's WaveEditor, you can see the volume has increased in the file.

LtData, as I mentioned in a previous post, I tried different programs with where they all have their own copy of LAME.

I have also tried to encode other FLAC files to MP3 using Music Converter and they sound fine. It just seems to be these files.

NoOne
07-26-2005, 03:24 AM
Anybody have a clue as to what is happening here? I really like this album and I would like to be able to listen to it on my MP3 player as well haha. Thanks for all your help so far.

ChristinaS
07-26-2005, 04:05 AM
Well, what I would do is play the flac files and record them to standard PCM uncompressed wave, 16-bit, 44.1KHz, 2-channel stereo with dMC Auxiliary Input as they are being played. Then convert the wav to mp3.

I wonder if it's possible the flac files are some kind of variable bit-rate and/or frequency, maybe yet another form of DRM, making it hard to simply convert.

xoas
07-26-2005, 07:25 AM
I wonder if the issue might be related to the characteristics of the audio (in interaction with the sound-shaping characteristics of mp3 technology).

Perhaps if you could compare the frequency characteristics of your two previous wave files (one flac to wav, the second Flac to mp3 to wav) you could determine whether there are particular frequencies being overemphasized or whether this is some overall boost at all frequencies.

Armed with this information you could use dMC's EQ DSP to address output at specific frequencies or you could reduce EQ boost or use volume quiten to reduce output across all frequencies.

This being said, I would try Christina's suggestion first. It's simpler although it probably would not address the problem I suggested. But my theory of this problem is hypothetical at this point anyway.

What music is it that is giving this problem?

Best wishes,
Bill