[nukaidee]

I'm looking for a "bass boost" in my headphones without an extra amp etc. I was wondering if it would be feasible to make a passive version of something similar, basically taking a single highpass (eg 150hz) and adding a resistor to it to attenuate it.  Therefore the bass should be stronger?
 
Thanks

 

[sampson_smith]

I am also interested in any info. on this. I do recall a few people here recommending that you can do something similar to a pair of Koss PortaPro's to attenuate the bass around said frequencies. So this could very well be a good idea, although I don't remember any pic's of this mod.

 

[nukaidee]

Dont really need pics, I was thinking about building right into a interconnect / headphone extension style cable.  Just seeing if the idea will work or will it not be good for audio quality? I already have a 50ohm cable that I use with my livewires, just thinking of adding more components to it.

 

[JaZZ]

Do you need it for at home or on the go? I see you have a Clip+ with built-in equalizer, which would of course be the ideal solution.
 
However, the simplest way would be serial resistors. I most cases they lead to an emphasis of the bass – since the bass resonance of a dynamic headphone is coupled with an impedance peak, and a serial resistance modifies the electrical frequency response accordingly. But you won't get an increase of lowest frequencies that way.
 
So the «best» you could do is to add an inductance (coil) with a resistor in parallel to it in series to the headphone driver. But note that the inductor values are quite impractical: For a 32 Ω headphone you'd need a 25 mH coil (plus say a 27 Ω resistor), for a 300 Ω headphone it would be a 238 mH coil (plus say a 270 Ω resistor) per channel – both for a corner frequency of 200 Ω. For 100 Hz it would be double that value. And note that the bass-resonance impedance peak would still make for some emphasis on its frequency, because the inductance would also have some (although minor) effect on it.
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