PD Fhg ACM codec 1999

Decoder Source: versions supplied with Easy CD Creator 4.0 and Media Jukebox
Version: decode only and advanced © 1996-1999 FhG
Price: supplied with various software
Settings: none
Similar products: Included in Easy CD Creator 4.0 and Media Jukebox and others.
Verdict: Excellent
VBR: All
Full file: Always
Major Flaws: None
Minor Flaws: Installing software may over-write this codec with a previous version without you realising.
Output level: correct
1-bit relative accuracy: Excellent
1-bit absolute accuracy: Excellent

An ACM codec is one installed within windows for the compression and decompression (encoding and decoding) of a certain media format. FhG, the inventors of mp3, have released various ACM mp3 codecs. Please see notes on ACM mp3 codecs for more information.

The ACM codec with a 1999 copyright date decodes mp3s faultlessly. Though ACM station couldn't handle all VBR files, when using the 1999 ACM codec within Easy CD Creator, all VBR files were handled correctly, proving that the codec itself is not at fault. If you are using a program that relies on the windows ACM to decode mp3 files, then installation of the ACM 1999 version will ensure that your mp3s are decoded correctly.

The only free way I know of to obtain the 1999 mp3 ACM codec is to install Media Jukebox. If you do not require that software, it can be uninstalled, and the codec will remain on your system.

Please see notes on ACM mp3 codecs for more information.



PD Fhg ACM codec 1997

Decoder Source: version supplied with mp3 producer pro v2.1
Version: decode only and advanced © 1996-1997 FhG
Price: distributed freely
Settings: none
Similar products: Even earlier version included with mp3 producer v1.
Verdict: Very Good
VBR: All
Full file: Always
Major Flaws: None
Minor Flaws: 128kbps files have slight 16kHz+ error on one channel.
Output level: correct
1-bit relative accuracy: Excellent
1-bit absolute accuracy: Excellent

An ACM codec is one installed within windows for the compression and decompression (encoding and decoding) of a certain media format. FhG, the inventors of mp3, have released various ACM mp3 codecs. Please see notes on ACM mp3 codecs for more information.

The ACM codec with a 1997 copyright date gives very slight high frequency errors on the left channel, but only when decoding 128kbps mp3s. If you are using this codec to decode mp3s, you could upgrade to the 1999 version which does not have this problem. However, the errors are very slight, and the newer codec may not offer all the features of your existing one.

Please see notes on ACM mp3 codecs for more information.


ACM mp3 codecs

The codec itself is installed in your windows system directory (usually C:\Windows\System\). The filename can be either:

l3codecx.acm-"decode only"
doesn't encode!
l3codeca.acm-"advanced"
decodes all bitrates. Only encodes up to 56kbps.
l3codecp.acm-"professional"
encodes and decodes all bitrates
l3codecx.ax-not acm
Installed by Windows Media Player 6.4

As you see, different file names refer to different codecs (decode/advanced/professional), all based around the same technology, but with different capabilities. For a given release date, all versions of the codec appear to give identical mp3 decodes - therefore no reference is made to "decode only" or "advanced" or "professional" in the mp3 decoder reviews.

ACM codecs (and their copyright date) are visible from the control panel. Go to Start:Settings:Control Panel; Multimedia:Advanced:Audio compression codecs. You should see "Fraunhofer IIS MPEG Layer-3 Codec (decode/advanced/professional)". Select it, go Settings:About to see the copyright date. The 1996-1997 and 1996-1999 versions are reviewed here. The 1998 version installed with Windows Media Player 6.4 (which is not really an ACM codec) behaves like the ACM 1996-1997 decode only version.

ACM codecs are supplied with various programs, sometimes to be freely distributed. A few are listed below.

supplied with...filenamenamecopyrightdescription
MPEG Layer-3 Producer v1.1b1 © 1996l3codecp.acmprofessional© 1996

The file l3codecp.exe will install this file on your system. Despite a comment that the ACM codec is for "Low Bitrates, Mono only" it encodes up to 128kbps. Its decoding has not been tested.
About and Properties info boxes.

mp3 producer pro v2.1l3codecx.acmdecode only© 1996-1997

mp3 producer pro includes a /redist directory. Running l3codecx.exe installs the decode only ACM codec on your system, reviewed here.
Install, About and Properties info boxes.

Microsoft Netshow?l3codeca.acmadvanced© 1996-1997Available on the net as a .zip file, this advanced version encodes up to 56kbps, and decodes as above. Installed with some Microsoft software at some point. Can anyone tell me what?
About and Properties info boxes.
don't ask mel3codecp.acmprofessional© 1996-1997Radium hack. After 1996 (above) FhG didn't release an ACM codec with full encoding facilities. This hack probably has the same decoding problems as the other two 1997 dated codecs.
About and Properties info boxes.
Easy CD Creator Deluxe 4.02l3codecx.acmdecode only© 1996-1999Installed with Easy CD Creator, the latest version of the decode only codec passed all our tests. Warning: Installing other software (ANY of the above codecs, for example) will remove this decoder from your system and replace it with an inferior product.
Media Jukebox 5.0l3codeca.acmadvanced© 1996-1999Installed with Media Jukebox, the latest version of the advanced codec passed all our decoding tests. Warning: Installing other software (some of the above codecs, for example) will remove this decoder from your system and may replace it with an inferior product.
About and Properties info boxes.

Click on the links in the table to see the "about" info boxes for the various codecs.

Return to the list of decoders.