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Author Topic: Question about which Sansa I should try to buy.  (Read 2270 times)

Offline OzziePants

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Question about which Sansa I should try to buy.
« on: June 20, 2009, 02:39:48 PM »
I have read the Buyer's Guide and, from what I can tell, Sansa products seem to be what I want.

I used to have an old Sansa Express and it worked...not well...but it worked.

The features I would like to be able to use in what I buy would be:

1. MicroSD/microSDHC memory support. Pretty sure e200v1/v2, c200v1/v2, and Fuzev1/v2 all support this.

2. USB cable to charge the player as well as transfer files. Pretty sure e200v1/v2, c200v1/v2, and Fuzev1/v2 all support this.

3. HE-AAC support. This is what is the main issue.

I haven't found what type of CPU c200v1/v2 or Fuzev1/v2 uses, but I did find this on Wikipedia.

Quote
CPU  v1-24 MHz (up to 80 MHz with Rockbox Firmware) v2-200mhz

Does that mean v2 is is over 100 times slower than v1? I guess this doesn't mean that HE-AAC decoding will be over 100 times worse on the v2 than v1 whenever Rockbox for Sansa AMS is ported completely but that seems like a huge difference in CPU speed.

And is there anywhere that list the CPU speed for c200v1/v2 or Fuzev1/v2?

Additionally, I was interested in using HE-AACv2 probably at 18kbs since I mostly want to use it for Audiobook CD's.

Would I be correct to assume that such a low bitrate would make decoding the files properly without skipping more likely?

Also, can anyone explain why for the iriver H10 5GB from the http://www.rockbox.org/twiki/bin/view/Main/CodecPerformanceComparison

AAC's realtime values were equal to the single HEv2-AAC's realtime value but for the iriver H340(60GB Drive) , AAC's realtime values were closer to HEv2AAC's realtime value?

Would it be possible that the comparison test for the iriver H10 5GB's test was a fluke?
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Offline saratoga

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Re: Question about which Sansa I should try to buy.
« Reply #1 on: June 20, 2009, 02:51:56 PM »
Quote from: OzziePants on June 20, 2009, 02:39:48 PM
I have read the Buyer's Guide and, from what I can tell, Sansa products seem to be what I want.

I used to have an old Sansa Express and it worked...not well...but it worked.

The features I would like to be able to use in what I buy would be:

1. MicroSD/microSDHC memory support. Pretty sure e200v1/v2, c200v1/v2, and Fuzev1/v2 all support this.

2. USB cable to charge the player as well as transfer files. Pretty sure e200v1/v2, c200v1/v2, and Fuzev1/v2 all support this.

3. HE-AAC support. This is what is the main issue.

I haven't found what type of CPU c200v1/v2 or Fuzev1/v2 uses, but I did find this on Wikipedia.

Check our wiki.  Theres plenty of information there.

Quote from: OzziePants on June 20, 2009, 02:39:48 PM
Quote
CPU  v1-24 MHz (up to 80 MHz with Rockbox Firmware) v2-200mhz

Does that mean v2 is is over 100 times slower than v1?

How do you get that 80 is one hundred times larger then 200?  But no, those numbers aren't even right.  The V1 has a dual core 80MHz chip, the e200V2 a single 250MHz.  They're not the same core though, so its difficult to compare to them by clock speed.


Quote from: OzziePants on June 20, 2009, 02:39:48 PM
Also, can anyone explain why for the iriver H10 5GB from the http://www.rockbox.org/twiki/bin/view/Main/CodecPerformanceComparison

AAC's realtime values were equal to the single HEv2-AAC's realtime value but for the iriver H340(60GB Drive) , AAC's realtime values were closer to HEv2AAC's realtime value?

Would it be possible that the comparison test for the iriver H10 5GB's test was a fluke?


I don't know what the Hev2 file tested.  It looks like probably a normal AAC-LC file.  Those tests are really old though.  I've improved the AAC decoder a lot since then.  It won't be real time on the V1 Sansas, but probably is on the V2s.
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Offline OzziePants

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Re: Question about which Sansa I should try to buy.
« Reply #2 on: June 20, 2009, 03:21:41 PM »
Quote from: saratoga on June 20, 2009, 02:51:56 PM
How do you get that 80 is one hundred times larger then 200?  But no, those numbers aren't even right.  The V1 has a dual core 80MHz chip, the e200V2 a single 250MHz.  They're not the same core though, so its difficult to compare to them by clock speed.

I was comparing the 24 MHz for the v1 and the 200 mhz for the v2.  I didn't think comparing the 80 MHz value obtained by using the Rockbox firmware would have been fair since Rockbox doesn't work on v2.

Though I might have thought 1 Mhz equals 1000 hz and 1 hz equals 1000 mhz which is a bit off anyway. My fault.

Quote
I don't know what the Hev2 file tested.  It looks like probably a normal AAC-LC file.  Those tests are really old though.  I've improved the AAC decoder a lot since then.  It won't be real time on the V1 Sansas, but probably is on the V2s.

That's good. I doubt I could find v1's very easily now anyway.

What about c200 V2's?

I see they have same SoC and that means they have the same CPU right?

I assume so from the datasheet I read for the E200v2. The datasheet link from:
 the http://www.rockbox.org/twiki/bin/view/Main/SansaC200v2
seemed to be a deadlink.

I don't really want to assume too much though since I'm rather new.
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Offline animatorgeek

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Re: Question about which Sansa I should try to buy.
« Reply #3 on: June 20, 2009, 06:01:20 PM »
Quote from: OzziePants on June 20, 2009, 03:21:41 PM
I was comparing the 24 MHz for the v1 and the 200 mhz for the v2.  I didn't think comparing the 80 MHz value obtained by using the Rockbox firmware would have been fair since Rockbox doesn't work on v2.

I think the problem here is capitalization.  In this case, MHz is the same thing as mhz.  The first one is more correct, since Hertz is abbreviated Hz.  So MHz (or mHz -- not sure which is more correct) simply means one million Hertz.  Based on the numbers you found on the Wikipedia page, the v2 runs at a little over 8 times the clock rate of the v1.
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Rockboxed iRiver h132, CF Mod, RTC Mod, 2200mAh battery

Offline yapper

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Re: Question about which Sansa I should try to buy.
« Reply #4 on: June 20, 2009, 06:05:23 PM »
MHz is mega Hertz (million cycles per second)
Lower case m is milli (1/1000th) but is not (usually) used when refering to frequencies.
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G2 iPod 20GB / Sansa c240 v1 + 2GB microSD / Sansa c250 v1 / Sansa e250 v1 + 8GB microSDHC / Sansa Fuze v2 + 32GB microSDHC

Offline OzziePants

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Re: Question about which Sansa I should try to buy.
« Reply #5 on: June 20, 2009, 06:47:23 PM »
That makes sense. I just assumed they were different since they were capitalized differently.

Either way, I think I get what the datasheet is saying now.

According to this, I guess my best bet is Fuzev1.

http://www.rockbox.org/twiki/bin/view/Main/SansaAMS

I guess I'll just need to wait for USB work to get done.

Though does anyone have any tips to get Fuzev1's? I normally buy everything online but I don't believe there are anyway to distinguish v1 and v2.
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Offline epithetless

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Re: Question about which Sansa I should try to buy.
« Reply #6 on: June 20, 2009, 07:56:15 PM »
Quote from: OzziePants on June 20, 2009, 06:47:23 PM
Though does anyone have any tips to get Fuzev1's? I normally buy everything online but I don't believe there are anyway to distinguish v1 and v2.

As someone who also buys predominantly online, my suggestion is to search out used or open-box players on sites like ebay or various gadget forums (e.g. head-fi.org or DAPreview.net) where you can communicate with the seller and/or post a specific "Want To Buy" request to ensure you're getting the right version. That's how I ended up finding my v1 Fuze and my v2 e280, both of which are in fine shape. You do end up sacrificing the ability to buy new that way, but otherwise it's a total crapshoot.
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Rockboxed: Apple iPod 3G â€¢ Apple iPod nano 2G • iriver H120 • Sansa c250 v1 • Sansa Clip v1 • Sansa Clip v2 • Sansa Clip+ • Sansa e280 v1 • Sansa e280v2 • Sansa Fuze v1  |  non-Rockboxed: HTC Incredible [Android 2.2] • Sansa Fuze v2

Offline saratoga

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Re: Question about which Sansa I should try to buy.
« Reply #7 on: June 20, 2009, 08:05:07 PM »
Quote from: animatorgeek on June 20, 2009, 06:01:20 PM
Based on the numbers you found on the Wikipedia page, the v2 runs at a little over 8 times the clock rate of the v1.

You mean the ones I already explained are wrong ;)
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Offline animatorgeek

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Re: Question about which Sansa I should try to buy.
« Reply #8 on: June 20, 2009, 08:09:14 PM »
Quote from: saratoga on June 20, 2009, 08:05:07 PM
You mean the ones I already explained are wrong ;)

Yes, those ones.  I was just trying to keep things simple -- an explanation of nomenclature, not of actual processor speed.

-David
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Rockboxed iRiver h132, CF Mod, RTC Mod, 2200mAh battery

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