[greenleaves]

I did a headphone-out and line-out SQ comparison on my IPOD 5G with Xin SM3-V3 headamp and Sennhesier HD600 a few days ago and found no perceivable SQ difference. This has been confirmed and discussed extensively in another threads.

I found instead a better SQ on Rockbox than the Apple firmware playing the same MP3-320kps files with volume set at 0db or 90% level, and EQ off. Rockbox has in comparison a clear, crisp and airy sound especailly in the mids and the highs, and a tighter bass.

There is a clear indication that the SQ on Rockbox 5G can be further improved. Here is a quote by linuxstb, a key Rockbox developer for 5G in another thread:

Quote:

Originally Posted by linuxstb If anyone is interested in helping make best use of this DAC, please read the datasheet, and let me know if you can spot any improvements which can be made to the way the DAC is initialised and used in Rockbox. The relevant Rockbox code can be seen here: http://www.rockbox.org/viewcvs.cgi/f....c?view=markup The audio driver for the 5g is still a work-in-progress, so please be gentle with me if you spot any mistakes... It's very possible that audio quality can be improved by initialising the DAC differently - I just haven't had the time to properly investigate it. Thanks.

 

[Jimothy]

Good to hear! I noticed a distinct improvement in SQ with Rockbox on my H320.

 

[crazychimp132]

Is the headphone volume when at full equal to the lineout volume? If not, the digital volume control (it is digital, right?) must be affecting the sound above a certain level. If this is the case, one possible feature that the Rockbox people could implement is the ability to select the line out volume for the headphone out. This would be the loudest level possible without actually altering the data. Using this feature, one could turn the headphone out into the exact equivalent of the lineout, and thus eliminate the need for a (relatively) bulky connector on the bottom.

 

[Bosk]

Pardon my ignorance but does installing Rockbox void the iPod's warranty? Do you need any additional hardware/software to make it work?

Cheers.

 

[fongalv]

Quote:

Originally Posted by Bosk Pardon my ignorance but does installing Rockbox void the iPod's warranty? Do you need any additional hardware/software to make it work? Cheers.

check it out here:
http://www.rockbox.org/

but in short: NO,NO,YES(rockbox IS the software or to be exact a firmware...)

 

[Bob_McBob]

I finally installed Rockbox last night. It is definitely not finished yet, but it's good enough for basic playback and such (and there are decent games!

). It is probably useful to have it installed if only to play back music copied from friends' computers when away from iTunes. I will probably try the foo_pod database rebuild trick so I can access the music library from Rockbox, but I hope they add the ability to read the iTunes database soon.

I tried a few skins, and the interface is useable. If you do too much at once, the audio will skip, but it no longer has the constant skipping problem on the 5G that was reported when it first came out.

I have not had any real time to evaluate the sound, but one thing I noticed right away was that the loud hiss I hear on my UM2s out of the headphone output is almost inaudible in Rockbox. I find it a bit bizarre that the noise floor could be a function of the firmware, but there is definitely a huge difference there. I wonder if Apple could improve things with a firmware update...

 

[fongalv]

Quote:

Originally Posted by Bob_McBob I finally installed Rockbox last night. It is definitely not finished yet, but it's good enough for basic playback and such (and there are decent games! ). It is probably useful to have it installed if only to play back music copied from friends' computers when away from iTunes. I will probably try the foo_pod database rebuild trick so I can access the music library from Rockbox, but I hope they add the ability to read the iTunes database soon. I tried a few skins, and the interface is useable. If you do too much at once, the audio will skip, but it no longer has the constant skipping problem on the 5G that was reported when it first came out. I have not had any real time to evaluate the sound, but one thing I noticed right away was that the loud hiss I hear on my UM2s out of the headphone output is almost inaudible in Rockbox. I find it a bit bizarre that the noise floor could be a function of the firmware, but there is definitely a huge difference there. I wonder if Apple could improve things with a firmware update...

hi...thanks for the info...1 question tho...hows the battery with rockbox?

 

[Bob_McBob]

Quote:

Originally Posted by fongalv hi...thanks for the info...1 question tho...hows the battery with rockbox?

It's supposed to be pretty poor at the moment (6 hours?), so it is not really a serious contender vs. the Apple firmware. It is progressing along at a good pace, though. Once they have ironed out the battery life and general performance issues, and integrated iTunes database support, I would seriously consider switching from the Apple firmware permanently.

 

[bigshot]

Doesn't it require a restart to switch from one system to the other? How did you compare the two? Did you have two iPods? The only way to detect a subtle difference like that accurately is a direct A/B test.

See ya
Steve

 

[ckhirnigs113]

Quote:

Doesn't it require a restart to switch from one system to the other?

You have to restart to go between the two systems. I am using Rockbox on my 4G iPod Photo with UM2s and I find the sound quality greatly improved. The EQ is much better on Rockbox as well, so the sound can be even more finely tuned.

 

[K2Grey]

Quote:

Originally Posted by crazychimp132 Is the headphone volume when at full equal to the lineout volume? If not, the digital volume control (it is digital, right?) must be affecting the sound above a certain level. If this is the case, one possible feature that the Rockbox people could implement is the ability to select the line out volume for the headphone out. This would be the loudest level possible without actually altering the data. Using this feature, one could turn the headphone out into the exact equivalent of the lineout, and thus eliminate the need for a (relatively) bulky connector on the bottom.

Rockbox can show the volume in terms of decibels of attenuation. The line-out volume is at 0db.

 

[mixxxer]

To MY EARS - non-eq'd Rockbox sounds much better that the apple firmware on my Nano. It is quite noticeable on my hard rock tests. MY EARS. I am not going to do any scientific testing to ever try and prove it to anyone.

However - right now - it still has issues. There is a thread going there right now named 'calling all testers - playback should be working' and I make alot of posts in that thread under the name 'CCBM'.

You will see from my newest experiences the last few days that it hasn't been working out well enough for me to keep. yet.

As a note. i usually test it out - then uninstall it and try it again every month or so. Have been testing it for about 4 months

It takes the length of a Nano restart to change OS's - so about 7 seconds? And in 'my ear tests' the Rockbox firmware, on the exact same mp3 sounds crisp, more punchy and not as dull as the apple firmware.

Never tested the line out.

The guys working on it do an amazing job, updating there code sometimes 4 or 5 times per day after fixing bugs people find...

 

[jonnywolfet]

i certainly noticed a difference in sound quality on a rockboxed 4g, driving my e4c, the ipod firmware sounds dull and lifeless, with really poor bass, rolled off, dull and without any impact. with rockbox, the bass returned, and was a lot more pleasent to listen to.
what he said, MY EARS.

im in the rockbox sounds better camp.

 

[bangraman]

It would be extremely difficult to recover the bass on the 4G at least, with a firmware change. I suppose it's time I did a test, the proper way with two iPods. Maybe later. Not sure it's worth bothering, as people can be extraordinarily hard to shake in their convictions that their flawed comparisons are correct, especially with something as subjective and easily influenced (by placebo / poor methodology) as audio.

 

[ProleArtThreat]

Quote:

Originally Posted by bangraman It would be extremely difficult to recover the bass on the 4G at least, with a firmware change. I suppose it's time I did a test, the proper way with two iPods. Maybe later. Not sure it's worth bothering, as people can be extraordinarily hard to shake in their convictions that their flawed comparisons are correct, especially with something as subjective and easily influenced (by placebo / poor methodology) as audio.

FWIW, I installed Rockbox on my 4G iPod Photo two weeks ago and found no discernible change in SQ one way or the other. The bass roll off was still there with the low impedance Shure E4 and Ety ER-4P. But admittedly I did not have another 4G iPod on hand to A/B with.

I eventually pulled Rockbox off my iPod as the only reason I would have kept it on was for SQ reasons as I don't listen to FLAC or any other lossless format for that matter on my portable players.