Micro SD HC Card, which class?

SanDisk MP3 players Sansa® Clip | Sansa® Clip+
1

There are 3 different classes in the market: class 2, 4 and 6. (as i know of)

I bet class 2 is enough for the clip+. But does it support class 4, for higher transfer speed?

Maybe a class 4 would be a better choice in general so you might use the card with other devices, etc.

What’s your opinion?

2

For music, the speed of the card matters only in how long it takes to fill it. Class 2 and Class 6 cards will do equally as well for playing audio. A class 2 card might take up to 3 times as long to fill than a class 6 card though, so if you change the music often, a class 2 card wouldn’t be the best choice. A class 4 card could take around half the time a class 2 card does to fill. I generally avoid class 2 cards, and buy class 4 or class 6 cards.

3

how do you know what the class of the card is?Ihad never heard of that.

4

you would think it would be that easy but actually it is not.

Class rating is a different way of performing benchmarks on a storage device and measures the minimum transfer speed using very small random file transfers across the entire capacity of the card. Manufacturers commonly rate the speed of a cards using a different method. manufacturers usually rate the speed of a card using larger file sequential read/write transfers, which is a more real world application. Class rating only determines what the minimum transfer speed should be and has no affect on the maximum transfer speed of the card. you can have a class 2 card with transfer speeds of 9MBps write and 15MBps read when using 2 or 3MB file transfers as is the case with the newest manufactured sandisk mobile ultra microSD/SDHC cards. class rating was designed for and is only relevant for hi def video capture as hi def video capture requires a sustained minimum speed through out the entire capacity of the card.   

Message Edited by drlucky on 12-11-2009 03:20 PM

5

The class number typically appears in a circle on the microSD card; however, not always, and some ads don’t mention it.

And the situation gets even murkier:  some manufacturers are better than others as to speed, even in the same class (remember, it’s a minimum).  From my research before I just gave up, SanDisk microSD cards often are better than others (and I’m not just saying this because this is SanDisk’s board!), and go well beyond the class minimum rating.  E.g., as compared to Kingston cards in a study I saw.  But who knows if this is universal, etc., etc.

6

well thanks guys.thats one of those little things i would have never thought to look into.I’ve got a sandisk and some cheap one that came with my phone so one out of two isnt bad i guess lol

7

Class 6 is ~10% more expensive than class2, I would get class 6 because of the higher speeds.

8

“Class 6 is ~10% more expensive than class2”

That is usually true for the smaller cards in the US, however for a 16 GB micro SDHC card, class 6 is much more expensive than class 2. When class 6 cards are much more expensive, I often choose a class 4 card. I usually avoid class 2 cards, but if the price difference between a class 4 card and a class 2 card is great enough, I would buy a class 2 card. Some people have said that outside the US often all class 4 and especially class 6 cards are so much more expensive than class 2 ones.

9

I never saw a need for more than a Class 2 for audio use when I had my Fuze. Maybe if you’re loading your card with videos it makes sense, but just for audio, I think you’d be wasting money buying a Class 6 card. If you really must save a couple minutes loading up the card, and want to pay more for the capability, knock yourself out…but if you’re on a budget ( and who isn’t in this economy? ) and doing just audio,  a Class 2 is just fine…at least a SanDisk one, where they usually outperform that minimum rating on the card.

10

@marvin_martian wrote:
I never saw a need for more than a Class 2 for audio use when I had my Fuze. Maybe if you’re loading your card with videos it makes sense, but just for audio, I think you’d be wasting money buying a Class 6 card. If you really must save a couple minutes loading up the card, and want to pay more for the capability, knock yourself out…but if you’re on a budget ( and who isn’t in this economy? ) and doing just audio,  a Class 2 is just fine…at least a SanDisk one, where they usually outperform that minimum rating on the card.

Exactly.  I have a mixture of cards…classes 2, 4 and 6; and for my purposes (audio only) they all work fine.  I usually get what is on sale; and that’s why I have a few class 6’s in my collection-- they happened to be on sale at the time I purchased them.  But, having said that, I wouldn’t go out of my way to get a class 6.  I tend to have so many projects going on at once, a few extra minutes for the card to load isn’t a big deal…for me at least.

11

The most recent card I bought was an 8 GB class 4 micro SDHC card for around $20. I could have saved at most around $5 buying a class 2 card, or paid around $4 more for a class 6 card. Since class 2 can take twice as long as class 4 to fill, I decided on the class 4 one. If someone will rarely or never change the content on it, then class 2 is good enough. I listen to plenty of podcasts though, and I frequently change those, while rarely make changes to the music. So if I listened to music only and didn’t swap music very often, I might not even pay $1 more for a card faster than class 2. A class 2 16 GB card might take up to 2 hours or so to fill completely, so someone changing content often on a 16 GB card might be willing to pay much more to fill the card in under 40 minutes(class 6) or under an hour(class 4) than to take up to 2 hours or so to fill a class 2 card.

Message Edited by JK98 on 12-15-2009 10:40 AM