Sunday, December 07, 2008

This American Life vs. the MP3-CD

There is this show on NPR called "This American Life" that I have been listening to for years. I have 104 podcasts of the show saved in various places, and it is one of the weekly shows I put on my iPod Shuffle for listening to during commutes to and from work (through my radio's auxiliary input, mind you, not headphones), and during my daily walks at lunchtime. I enjoy Ira Glass' interview style, the topics of the show, and the recurring guest speakers such as Sarah Vowell and David Sedaris. The show is more refreshing than Terry Gross' interviews on "Fresh Air", and more substantive (and sometimes almost as funny) as "Wait, Wait, Don't Tell Me" with Peter Sagal, Carl Kasell, and various panelists. There are interesting and bizarre things I never would have heard of without this show, La Pulcina Piccola, a finger puppet opera about Chicken Little (pulcina.org, check it out), and summer camps run by the Israeli military that let young girls fire live ammo (here), to name a couple.

So I have these in-laws now that are pretty cool. They, like all the girls in their family, are artsy, and I heard a story about the dad, Steve, giving one of the girls a present of a book or CD that had to do with Garrison Keillor of "A Prairie Home Companion" fame, so they're familiar with things NPR already. With Christmas coming up, I thought hey, how cool would it be to give them a present of a bunch of This American Life burned to CD? The only problem is, they don't have a computer to speak of to play mp3s, and their home audio system is older, and hence probably can't play mp3s burned to CD. My 104 hour-long shows burned in audio disk format would take around 78 CDs... and may still not play in their home system if it is only compatible with Red Book CDs and not CD-R. That's a bad plan. "Here, Mom and Dad Allerding, here's a crate full of CDs, and some cork and glue in case you need to just turn them into coasters." No, what I needed was something as an accessory that was reasonably priced, portable, and could play MP3 CDs.

What's in fashion now in portable audio are boomboxes you can plug an iPod into, or mp3 players that require interfacing to a computer to load up on files. Since most people have computers with net access these days, or cell phones that you can download songs over the cell network, there is a very small market for CD players that can read mp3 files off of the disk. I managed to find one that was inexpensive and had good reviews on Amazon, but with one reviewer saying the following about it, which was relevant:

Not great for podcasts, otherwise fine

I picked this product up specifically for playing MP3 podcasts burnt to a CD. The podcasts play, but are cut off part of the way through. They are usually an hour long each and seem to cut short about halfway through. I'm wondering if it has a max length it can play for a single mp3 before it freaks and skips to the next one.

Anyway, since that was the primary reason I purchased it, I'm a bit disappointed. Otherwise it seems like a good product.


OK, so I won't order that off of Amazon. I shelved the idea for a few days, and this Saturday I went out doing my final round of Christmas shopping and stopped by Target. In the electronics department, I immediately found a boombox for $40 that said it could play MP3-CDs, the Memorex MP-4047. "Hot damn!" thought I, and I bought it along with some blank CDs, and went home to burn some podcasts.

Along the way, I got nervous about the one Amazon review, and looked it back up to see what product he was reviewing. Unsurprisingly, it was the Memorex MP-4047. So before I gave a well meaning but utterly useless gift, I decided to check one of the CDs I had just burned to see if it had the problem the Amazon guy spoke of. Sadly, it did. There were some files that had some clips in them, and they skipped to the next track after about 20 minutes. One file clipped less frequently, and skipped to the next track after about 30 minutes, and a few played through all the way without any problems.

I did an Internet search on the player, finding lots of retail outlets selling it, the Amazon reviews copied across multiple sites verbatim, and nothing else. The thriving community of Linux geeks were no help, since, again, there is no market for this type of device. I downloaded the manual from memorex.com (so I didn't have to break the seal on the printed manual, and I could still make the player look the the box had never been opened), and went to its troubleshooting section. There was no mention of limitations on mp3 files, no max or min bitrate, max song length, nothing.

Left to my own devices, and thinking like a programmer being rushed to get a product out the door that no one will ever use, I conjectured that each time there was an audible clip in the file the boombox was playing, it incremented an error counter. Once the error counter reached a given number, the file was aborted. This makes sense on 5 minute songs, as they would sound like crap if, say, 25 clips were encountered before the song ended. An hour-long podcast with a chirp every minute or two is a different animal, though; you can ignore the anomalies, and be really interested in the conclusion of the discussion. Having the player abort before you got to the punchline of an hour long show... that would really suck.

There were a number of approaches I could have taken at this point. I could have split each mp3 file into 10 minute chunks, assuming that no 10-minute file would contain enough errors to cause an abort. I could convert the files into the other file format the MP-4047 supports, WMA files. Lastly, I could re-sample the mp3s with something that had good bitrate and sound level control. I did the latter, since there was less file manipulation and research involved, using the "lame" application (an anagram that stands for "Lame Ain't an Mp3 Encoder") on my Linux box, forcing the files to mono and 44.1 kHz using the following command line:

for x in *.mp3; do lame --mp3input -m m --resample 44.1 $x /home/curtis/Desktop/resamples/$x; done


Having 100 files to go through, and each hour-long file taking roughly 3 minutes to resample, I had some time on my hands, so I went to the store to buy some more baking materials for Liberty's project to bake two complete iterations of Amish Friendship Bread in one day -- 16 loaves -- so that she can give them out as presents and bring some to potlucks.

I spent a grand total of 4 hours listening to the first disk I burned with the new files. There were no audible clips in the podcasts, and all of them played to completion. Success!

So I did two things this weekend of note: I crossed my in-laws off of my Christmas shopping list, and applied my universal problem solving algorithm to a problem that had previously flown under the radar of my geek brethren. Plus I've been chowin' on friendship bread all day. All-around good weekend. And to the Allerding family and friends who stumble across this prior to Christmas... Shhhh!

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