Does Secure Digital Speed Matter?

I'm interested in buying a SD card to play music on my Tungsten T. I've had the Tungsten for several years and this will be my first experience with a memory expansion card. I'm pretty certain I will only use it to store and play music, since I've had the PDA for this long and haven't had a need to expand the memory.

With that said, how important is the speed of the card when it comes to playing music? I've seen a lot about write-speeds for taking pictures with a digital camera, but I suppose read speed would be more of a factor for playing music.

I'm looking for a 512K card and there are some that are very inexpensive, but as usual, you get what you pay for. So I'm wondering what I should be looking for in a card that will mainly serve as a source to store/play music.

TIA.

Tipsy
 
I am not an authority on this issue but I think any SD card you can buy will work for the application you want it for. In other words, speed does matter but your requirements of just reading an audio file are not very demanding. I think the slowest of cards will do it without any problem.

I don't know how fast my card is rated to be, but I can play an mp3 with pocketTunes simultaneously while watching a movie with TCPMP and both the mp3 and the movie play perfectly. Both are also on the SD card. My card is a 1GB that I got for $10 after rebates, on Buy.com so I expect it is not a very fast card for that kind of money.
 
MMC is slower than SD, both are quite fine to play MP3, the only problem would be when your card is big, 512Mb, 1Gb... since it takes a little more for the system to read the information before to be ready.

Not something to worry, at least you have literally thousands of images or mp3 so your media player or multimedia program take a time to present the information.
 
I have no problems with my TX.

I don't think the speed of the card is really much of an issue with MP3 or WMA files. The files are compressed (WMA has even higher compression) and have to be decompressed (which takes time) before the data makes it to the speakers. This puts more strain on the processor performance than memory fetches. I have used some cheap memory as well as some more expensive and higher performing memory and have not had any skipping issues with either.

Digital cameras are another issue alltogether. Todays cameras snap 3-6+ Megapixels (which are usually compressed into JPGs) and must be able to do this in the blink of an eye. For this, SD performance becomes more of an issue as the image's pixel density increases. Most MP3 music files are significantly smaller than most of the JPGs. And it takes 'minutes' to play a MP3 but a good quality camera must be able to render, compress, and save a picture into a JPG in only a few miliseconds.

In the camera, the processing is usually done realtime in hardware. In the Palm, the MP3 file is processed by software, which results in a higher demand for a good (and fast) processor.


Cheers,
John
 
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