Rockbox General > Rockbox General Discussion

The iPod Poor Bass Response

(1/10) > >>

PHK Brasil:
PART 1

This is not a new, but, for those who doesn't know, iPods got problems on the bass response when using some headphones. The lower the impedance, the worst is the problem.

These are the results of the frequency response test, I did with my iPod 5G.

Although most of the mobile headphones have 16 or 32 Ohm, I used a lot of impedance values to check what happens above 32 Ohm too.

Is not just a sub 32 Ohm problem.






PART 2

I did two simple settings on Rockbox EQ, trying to compensate the bass response attenuation. The graphs shows a better response with the compensating EQ. I didn't spent much time doing this, therefore, is not 100%.






For those who wanna check, compare the sound between these EQ presets and flat, to notice the difference.

Is not a big deal, but exists, and is bigger with 16 Ohm headphones.


Compensating EQ for 16 Ohm:

Advanced EQ Settings:
Low Shelf Filter -> Cutoff Frequency: 50 Hertz
Low Shelf Filter -> Q: 0.6 Q
Low Shelf Filter -> Gain: 3.0 dB
Peak Filter 1 -> Center Frequency: 20 Hertz
Peak Filter 1 -> Q: 0.5 Q
Peak Filter 1 -> Gain: 0.5 dB



Compensating EQ for 32 OHm:

Advanced EQ Settings:
Low Shelf Filter -> Cutoff Frequency: 20 Hertz
Low Shelf Filter -> Q: 0.6 Q
Low Shelf Filter -> Gain: 3.0 dB


PS: Thanks to saratoga for the help.

♪

lights0ut:
Thanks PHK, glad to see a more tailor made solution rather than just turning the bass up. It's disappointing to know that a company who's market share is ~80% wont make a quality DAP.
(yet another reason why I wish my ipod was a gigabeat ;))

Febs:
Thanks for posting the graphs.


--- Quote from: PHK Brasil on March 27, 2007, 11:19:19 PM ---PART 1Is not just a sub 32 Ohm problem.
--- End quote ---

For sub-32 Ohm loads, the graphs clearly show a problem, but for higher loads, it looks much less significant.  The bass attenuation at 50Hz for a 32 Ohm load is less than half a dB at 50Hz and 1dB at 30Hz.  I'm not sure that would be audible.

DefineByte:
Is the line out any better?

saratoga:

--- Quote from: DefineByte on March 28, 2007, 07:41:29 AM ---Is the line out any better?

--- End quote ---

I don't think you'd want to drive a load with the line out anyway, so it shouldn't matter.

Navigation

[0] Message Index

[#] Next page