Iaudio X5: Sound Quality

[whosondephone]

I have heard rumors on the web that the sound quality is not as good using rockbox firmware compared to the original.  After experimenting I found the rumors to be true.  On the headphones the bass sounded more linear, and the over all sound was smother and more natural sounding. 

I work in the high end consumer audio industry for a company called Symposium.  I hooked my player up to my boss's custom built ribbon driver system through the line out of the subpack.  There was no bass at all.  My boss speculated there is an impedance mismatch.  We weren't using a preamp, I believe it went to an attenuator right to the power amplifiers.  Then we tried switching to the headphone out and it had more bass.  I've yet to try it on his system using the original firmware.  I intend to get back with my findings. 

Is this something your aware of?  I'm not saying rockbox sounds bad.  I don't think most people would notice the difference.  I'm wondering what you think about this.

[soap]

I find it interesting that you go so far as to mention "ribbon driver" and "bass" in the same breath.

If there was an impedance mismatch, you are aware that impedance is a hardware issue and not one of firmware?  One should also be aware that the X5's line-out's impedance is just fine and that any mismatch therefore is on the side of the amp.

RMAA Rockbox versus the OF if you have serious concerns.  A lack of bass would show right up.
 

[saratoga]

Is this something your aware of?  I'm not saying rockbox sounds bad.  I don't think most people would notice the difference.  I'm wondering what you think about this.

As far as we know there is no problem, and output is identical.  If you've got a problem, feel free to provide updated RMAA tests.  Otherwise we'll probably just assume its an issue with your specific player or audio equipment.

[whosondephone]

I'm sorry I have found the bass problem to be that the iAudio X5 is simply not powerful enough to go through a passive preamp.

That being said.  I still think roxbox clearly sounds different than the cowon firmware.  On listening to a FLAC file Scarborough Fair by Simon & Garfunkel I i hear that the cowon's firmware sounds much more relaxed and natural sounding.  Where as the Rockbox firmware sounds sharper and harsher.  I'm taking a shot in the dark but i believe that it has to do with the filter.

I do not want you to think I’m complaining.  I love rockbox and am interested in helping the project in many ways. 

[yapper]

If you've got a problem, feel free to provide updated RMAA tests.