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Rockbox General => Rockbox General Discussion => Topic started by: Mihail Zenkov on April 09, 2016, 08:58:31 AM

Title: Are you use player with rockbox with loudspeakers (in car/home stereo/etc)?
Post by: Mihail Zenkov on April 09, 2016, 08:58:31 AM

I want add new feature to rockbox (it can help to improve sound quality when player used with loudspeakers) and just curious how many people use loudspeakers with rockbox.

Title: Re: Are you use player with rockbox with loudspeakers (in car/home stereo/etc)?
Post by: johnb on April 09, 2016, 09:35:51 AM

Hi Mihail,

I mostly use my Sansas with headphones (for some with amp NX-1).

I have created two cfg files:
Line-out with headphones+amp: volume:0, crossfeed:meier, replaygain
Line-out with speakers (rather home stereo): same as above, but crossfeed off.

What improvements or special settings are you thinking of?

Title: Re: Are you use player with rockbox with loudspeakers (in car/home stereo/etc)?
Post by: Mihail Zenkov on April 09, 2016, 10:01:10 AM

I use DRC (https://en.wikipedia.org/wiki/Digital_room_correction) in car and home - just fantastic sound improvement. But it quite hard in usage, especially for ordinary users, so I want integrate it in rockbox and make it user friendly. I still not sure is it possible, but I want to try.

Title: Re: Are you use player with rockbox with loudspeakers (in car/home stereo/etc)?
Post by: saratoga on April 09, 2016, 12:46:39 PM

There are people on headfi trying similar things using the eq in rockbox to flatten out the response of headphones, so it could work for anything.

I always thought about making a plugin to help measure the response and create eq curves (or impulse responses). I never had time though.

Title: Re: Are you use player with rockbox with loudspeakers (in car/home stereo/etc)?
Post by: Mihail Zenkov on April 09, 2016, 01:36:08 PM

Quote from: saratoga on April 09, 2016, 12:46:39 PM

There are people on headfi trying similar things using the eq in rockbox to flatten out the response of headphones, so it could work for anything.

Not exactly. Basic EQ breakup phase. DRC linearize phase.
For real room (and especially for car) correction we also want eliminate strong early reflection (http://www.readyacoustics.com/early-reflections-explained.html?chapter=0 ).

So we need FIR (and fast CPU for it).

EDIT: Also correction should be done separately for left and right channels.