android
  #1  
Old 06-11-2008, 04:10 PM
trundyl trundyl is offline
Junior Member
 
Join Date: Oct 2007
Posts: 2
Default Battery life – MP3 vs. DRM WMA

I just completed some battery life tests on my new 4GB Clip and the results were not what I was expecting. The executive summary is that standard MP3 audio gives much greater battery life than for DRM WMA audio. I ran a test to determine the battery life, mostly to see if my new device had a problem and needed to be returned. After a full charge, I played a 20+ hour OverDrive audio book (DRM 32kbps WMA). The Clip went 12 hours 18 minutes before being fully discharged. It’s easy to determine the time by using the “Resume?” option for audio books. This was disappointing and I was suspecting that I had a bad device. So, I ran a second test trying to set it up in a mode that would give me the best possible battery life result. I ripped a CD to 128k MP3, transferred to the Clip, and had it play the album in a loop. It lasted 17 hours 33 minutes! That’s a big difference.
I don’t know if the significant factor is the bitrate, WMA format, or the DRM, but I am suspecting the DRM. I suppose it’s possible that you may need to fully discharge the battery before fully charging to get the best results, but I have a hard time believing that.
Testing details: FW was 18a then upgraded to 29a. None of the defaults were changed. Sample music was removed from device then the Clip was formatted via the Settings menu. OverDrive audio book was downloaded to Audiobook folder. JVC fx66 earphones installed – volume, as with everything else, still at default. I disconnected from the computer and started the audiobook. For the MP3 test, everything was the same except I started the play while still attached to a USB charger (not a computer) and waited until the display went dark before disconnecting.
Reply With Quote

Advertisement [Remove Advertisement]

  #2  
Old 06-11-2008, 04:30 PM
dfkt's Avatar
dfkt dfkt is offline
Moderator
 
Join Date: May 2006
Location: Vienna, Austria
Posts: 15,330
Default

DRM is crap, for sure, and nobody should support these rip-off schemes - but it's WMA that is a lot more processor intensive than MP3.

Don't use WMA if possible, there are no advantages to the format (no, WMA doesn't sound "better" than LAME MP3 at the same bitrates).
__________________
Please don't PM me with questions that can be answered in a forum thread. Don't be an idiot.
My Gear and Reviews | My RMAA Tests | IRC: #anythingbutipod on Freenode | Last.fm | Album Art Exchange | Rockbox | Replaygain
Reply With Quote

  #3  
Old 06-11-2008, 10:47 PM
unpocoloco unpocoloco is offline
Junior Member
 
Join Date: Mar 2008
Posts: 25
Default

DRM definitely could have a huge effect, and the bitrate could too. If you've got the stamina and/or drive left, I'd love to hear how a comparison between identical bitrates stacks up!

Also, you could test the bitrate itself by ripping a CD in two different rates, then testing. Keeps the number of variables as low as possible
Reply With Quote

  #4  
Old 06-23-2008, 02:22 PM
rdow rdow is offline
Junior Member
 
Join Date: Jun 2007
Posts: 45
Default

"rip-off" is a bit extreme. Philosophically I wish there wasn't DRM, but I've spent the last 6 months listening to nothing but FREE Overdrive audiobooks (with DRM) from my library... hard to call that a rip-off.
Reply With Quote

  #5  
Old 06-24-2008, 02:44 AM
Syndrome's Avatar
Syndrome Syndrome is offline
Redneck Moderator
 
Join Date: Dec 2007
Posts: 1,278
Default

Yeah DRM is a rip off, the bandwidth you used would have been better spent download a different free version without DRM. DRM deserves to die. No matter what I play on my clip, I find the battery life to be insufficient, and it charges much to slow.
Reply With Quote

  #6  
Old 06-24-2008, 11:14 AM
rdow rdow is offline
Junior Member
 
Join Date: Jun 2007
Posts: 45
Default

Not sure what bandwidth you are referring to... the Overdrive file size is smaller than the size of full mp3s for the same book if I downloaded from some usenet site. Quality is consistent (unlike usenet) and there is no legal issues/questions. I easily get two days of listening between charges and I charge overnight so I've got no complaints about battery life or charging time.

My problem is semantics... "rip-off" just isn't accurate. DRM can be a pain, hopefully the industry will move away from it and people will buy their songs/audiobooks or get from the library on an honor basis. That would be great. But in the mean time getting free, full length, consistent quality audiobooks with DRM from my public library is NOT a "rip-off" in my book.
Reply With Quote

  #7  
Old 06-24-2008, 11:52 AM
dfkt's Avatar
dfkt dfkt is offline
Moderator
 
Join Date: May 2006
Location: Vienna, Austria
Posts: 15,330
Default

Ok, so free Overdrive books from your library are no rip-off. Paying iTunes or whatever other store per single DRMed track (and not being able to do what you want with it) is, in my opinion, a rip-off. I hope we can agree on that.

Good thing times are changing and DRM is going the way of the Dodo.

Back on topic: battery life, WMA vs. MP3.
__________________
Please don't PM me with questions that can be answered in a forum thread. Don't be an idiot.
My Gear and Reviews | My RMAA Tests | IRC: #anythingbutipod on Freenode | Last.fm | Album Art Exchange | Rockbox | Replaygain
Reply With Quote

  #8  
Old 06-24-2008, 11:54 AM
rdow rdow is offline
Junior Member
 
Join Date: Jun 2007
Posts: 45
Default

Agreed! Sorry for the semantics tangent
Reply With Quote

  #9  
Old 12-24-2008, 07:58 PM
gsolo gsolo is offline
Junior Member
 
Join Date: May 2008
Posts: 17
Default

I just bought a 4GB model. Current firmware. I loaded only FLAC files so far and I seem to be getting substantially less than 15 hours (my guess is 10 or less). I will try running a flac file on loop and mp3 over the next few days and post the results
Reply With Quote

  #10  
Old 02-12-2009, 02:43 PM
Michael1406 Michael1406 is offline
Junior Member
 
Join Date: Feb 2009
Posts: 3
Default

This thread is a little old now, but back when I had my Creative Zen Touch 20GB, they recommended keeping tracks short as a method of preserving battery life. Perhaps this is why the cycle using the 20hr Audiobook lasted a lot less than the album of 3-5 minute songs?
Reply With Quote

  #11  
Old 02-12-2009, 04:48 PM
saratoga saratoga is offline
Rockbox Developer / Moderator
 
Join Date: Apr 2007
Posts: 3,608
Default

Quote:
Originally Posted by Michael1406 View Post
Perhaps this is why the cycle using the 20hr Audiobook lasted a lot less than the album of 3-5 minute songs?
Thats because it was a HD player. The clip is a flash device, so that advice doesn't apply.
Reply With Quote

  #12  
Old 02-13-2009, 05:22 PM
Michael1406 Michael1406 is offline
Junior Member
 
Join Date: Feb 2009
Posts: 3
Default

Ahh, fair enough. I got my 8GB V2 clip yesterday, I'm trying to work out exactly how much I've used it today. I used it for about 60 minutes on half volume, then about 15 minutes on full volume, then about 30 minutes on 1/3 volume. I've been using it for about 75 minutes on 1/4 volume and I'm still using it now. It's down to 78% according to the system info.
Extra info: backlight is set to 10 seconds timeout, brightness is minimum, auto-turn off is 1 minute.

I tend to worry when it comes to battery life though. The Clip sticks to set battery percentages (100, then jumps to 92, then 85, then 78), but does anyone know whether it jumps when it gets to 92% (for example), or when it's closer to 92 than 100? Either way I guess I'm on track for a 15 hour life span.

Despite the quality losses, I think I will transcode some 320s down to v2/3 VBRs. When when I replace these stock earbuds with some plugs, I will have the volume even lower.

Last edited by Michael1406; 02-13-2009 at 05:45 PM.
Reply With Quote

  #13  
Old 02-13-2009, 05:55 PM
saratoga saratoga is offline
Rockbox Developer / Moderator
 
Join Date: Apr 2007
Posts: 3,608
Default

The battery meter is just a rough estimate. You should not try to guess how long the battery is going to last based on how long it takes to get to any percentile other then 0%.
Reply With Quote

Reply

Tags
battery, drm, overdrive

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump



All times are GMT -5. The time now is 06:38 PM.