Do you lose audio quality if you string together mp3s?

[ACBrown]

I recently recorded a fifteen minute monologue. I didn’t record it all at once, however, but broke it up into parts. Let’s say there were 8 sections. So I recorded each, exported each as an mp3 (128) and then strung them together (imported them) and re-exported as a single mp3. My voice now sounds a little, oh, electronicky, if you will. Basically, it’s not as clear now. Is that because I strung together a series of mp3s, or is due to something else? If yes, then how might I avoid that problem?

Any thoughts?

Thanks!

[kozikowski]

Yes. Stop doing that. MP3 is a single, final delivery format, not a production format. It causes damage. All production and show management should be performed in WAV or other uncompressed format. Then you wouldn't have these multiple pass problems.

Unless you also saved your Audacity Projects, you are now starting over. You can't recover from MP3 damage.

Koz

[kozikowski]

One note. You can export your mix as WAV or other uncompressed format and it will sound like it did when you mixed it, but neither you nor anybody else can ever make another MP3 at the same 128 quality.

You can also make an MP3 at "insanely high" quality and that works, too, but if you're going to go that far, you might just as well use the perfect WAV format. Yes, the file sizes go way up when you stop using MP3. That's the way it works.

Koz

[ACBrown]

Thank you very much!... kinda... I didn't save them, so I guess I'm starting over But it's really good to know. Due to their taking up so much size, I thought I would record, save as mp3 and then link them together. Live and learn, I guess.

Also, while I've got you here, Koz, I'm using my gaming headphone mic to record (Logitech). My voice isn't as loud as I would like it (and the input is max, I think), so is it better to amplify (under effects) the voice or increase the gain (off to the left on the track)?

Thanks!

[ACBrown]

But wait! Isn't using multiple mp3s kinda unavoidable? Take my scenerio. I've got this podcast . The beginning has three seperate mp3s going on to create the overall effect- one is music on a track, one is applause on another track, and one is voice on another track. Granted, that is a far cry from splicing together 8 mp3 voice segments into one, but I'm stuck with using mp3 music and applause. Is that going to interfere with the voice?

Thanks!

[kozikowski]

<<<increase the gain (off to the left on the track)?>>>

Use Effect > Amplify. The tools on the left are a little magic and don't always affect the "real" show.

USB microphones have some interesting problems. You can't actually do what they're doing -- create a high quality, digital voice signal with no knobs or controls. "Too Loud" or overload is permanent, awful sounding, and fatal, so they can't do that. Too soft is easily fixed in post production, so a very common complaint on the forum is USB microphones with no volume. Some USB adapters have that problem, too.

http://forum.audacityteam.org/viewtopic ... =20#p81588

This is an offshoot of the natural assumption that you're going to sing into your $80 microphone and it's going to sound like M&M. Even M&M can't do that. Post production is the answer.


<<<Isn't using multiple mp3s kinda unavoidable? >>>

It is if you're doing this for free, yes. If you're doing a commercial radio production, you pay for uncompressed work and do everything in high quality format so no matter where the show goes or what happens to it -- transmission, recompression -- there is little or no damage.

Car Talk is produced at WBUR in Boston at perfect, uncompressed quality. It goes out the NPR satellites and takes a very slight quality hit. I listen to it on the Los Angeles KPCC Streaming service which is compressed from the Radio Broadcast 89.3 MHz. There is also an archival podcast later in the week which has noticeable compression damage -- particularly compared to the radio broadcast.

None of that would be possible without the uncompressed studio production at the beginning.

Koz

[ACBrown]

Thank you, Koz. That pretty much hit the nail on the head. And since I'm basically playing around with this stuff, it looks like I'm going to have to live with some audio degredation... which is fine. As long as I don't string together a butt load of mp3 segments, the audio quality isn't too bad. I mean it's not perfect, but I doubt someone is going to turn it off due to the sound quality.

Thanks again! It really helped a noob.

Austin

[kozikowski]

<<<I doubt someone is going to turn it off due to the sound quality.>>>

Exactly. And the vast majority of podcast producers have no idea what's happening and think it's normal. Somebody did a poll of college students and they think undistorted music sounds funny.

I can't listen to Sirius radio. It sounds like I need to get my tools and fix it.

Past the quality issue, Producers (capitol "P") hate surprises. Spending hours editing a show and have it turn to peanut butter just before presentation is not a good surprise.

Koz