Q: Why doesn't Kagi handle the payments anymore?
A: Kagi has unexpectedly ceased operations as of July 31st, 2016 (see Kagi.com for more information). I was forced to quickly find a new solution for paying customers. The result is the MP3 Trimmer webshop where you can buy your license. I know it's a bit ugly looking, and not as the good-old Kagi shop, but this is the best I can do for now. Maybe someday I will re-think Apple's AppStore, but probably not. To become an 'identified developer' I have to pay Apple $99 every year. In addition they will take 30% of my revenues. Not the most tempting offer, I can assure you...

Q: Mac OS refuses to launch MP3 Trimmer!
A: A few years ago, Apple decided to restrict the ability to launch apps not installed from their AppStore (or in their words; from 'identified developers'). Fortunately, you can easily change this in your security settings. However, since Mac OS Sierra they decided to 'hide' this option. I really can't see any other reason behind this than to further force developers to the AppStore. Well, you can easily get the option back, just follow these instructions.

Q: I have not received/can't find my serial number!
A: First, make sure your payment was successful. You should get an e-mail from PayPal about your payment. I will send the license/serial number as soon as I have received a notification from PayPal about your payment. But please allow for some hours of delay since I work, eat, sleep etc like all humans. If you are concerned about a missing/lost license, please contact me.

Q: Why must MP3 Trimmer analyze each file?
A: MP3 Trimmer features an advanced MPEG audio parser that validates the integrity of each frame of the MP3 file. It's necessary that every frame is intact if you are going to edit the file, otherwise you might end up with a totally messed up file. Skipping this validation might work fine in 99 out of 100 sessions, but few people wish to gamble with their MP3s. In addition, it's often valuable to be alerted if the MP3 file is in bad shape. If the file is not too damaged, MP3 Trimmer will repair the file with the built-in repair feature.

Q: Is it possible to edit aac/m4a/mp4-files?
A: No, the AAC/mp4 format is very different from MP3. All internal routines is specially written to handle the MP3 audio format. The name says it all - MP3 Trimmer handles MP3 files.

Q: How come there is no quality loss?
A: MP3 Trimmer works with the actual binary data and extracts the audio frames at their boundaries. In order to do this with precision, MP3 Trimmer needs to analyze and 'learn' all frame boundaries when it imports the file. Incorrect editing of MP3s will inevitably result in a corrupt file. During waveform analysis, gain adjustments, and fade-in/out MP3 Trimmer needs to 'dig even deeper' inside the data (to single bit level) in order to parse and alter the bits necessary - thats why such actions takes somewhat longer to perform. But - the big reward is that the audio quality of each single frame (an average song consists of almost 10,000 frames) is exactly the same as the original!

Q: My music file does not work with MP3 Trimmer!
A: MP3 Trimmer is specially written to perform binary editing of compressed MPEG audio files (Layer 1, 2 and 3, i.e "MP3"). If you try to import other audio files (WAV, Aiff, etc) it will simply not work. There are plenty of regular audio editors available for this.

Q: Trimmer says my MP3 needs repair, but it plays fine in iTunes...
A: Many playback application (like iTunes) have built-in "error-correction" during playback. Instead of rejecting the song, or simply halt the playback, it will skip, or fill-in, bad parts during playback. Quite often, this is hardly noticable to the listener. On the other hand, when editing the file, these bad parts could really mess things up!

Q: Why can't I join these two files together?
A: When joining MPEG audio files, there are some audio characteristics (like bitrate, frequency, etc) that needs to match in order to join the files correctly. In order to conform to MP3 standards, and be sure that the joined file will play in all applications and portable MP3 players, these restrictions cannot be overridden. More in-depth information about joining is available by clicking the Info-button in the Joiner window.

Q: Can I change a song from stereo to mono without re-encoding?
A: Unfortunately, this can only be achieved by re-encoding the files. The MPEG compression algorithms are simply too complex. When a file is encoded in a particular audio mode (like stereo or mono) every single frame in the file contains information about this.

Q: I want to reduce the size of my files without changing the length!
A: Again, this can only be achieved by re-encoding the files. You need to convert the MP3 files to an uncompressed audio format (i.e Wave), and then encode to MP3 again, but with a lower bitrate (needless to say, audio quality will suffer). This can be done with iTunes, but if you need more encoding options there are freeware alternatives as well.

Q: Should I encode my files to MP3, AAC, m4a or what..!?
A: This is a common question, and my answer is always to investigate each option thouroughly, and then decide - before doing massive encodings. Each technique has its pro's and con's. "MP3" is the only format that will work on almost everything imaginable, but you can achieve smaller files with the same audio quality in other formats, but perhaps at the cost of incompatibility with various hardware and players.

Q: I have written to you, but got no response...
A: Unlike big software companies, I develop MP3 Trimmer on my spare time. I have a regular fulltime job and a family as well. Be patient, or in urgent matters, send me a reminder about your email.