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Date: Wed, 14 Mar 2012 13:53:59 +0100
Message-ID: <CABax29X+ke_PO9obAxbEJjdx68g8JW4ZZn7vS7mYpE7+00iYng@mail.gmail.com>
Subject: Re: A2DP quality (bluetooth-alsa)
From: qduaty <qduaty@gmail.com>
To: linux-bluetooth@vger.kernel.org
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Sender: linux-bluetooth-owner@vger.kernel.org
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2012/3/13 Siarhei Siamashka <siarhei.siamashka@gmail.com>:
> Are you now comparing streaming of A2DP audio from your phone to your
> PC (using bluez A2DP sink) and to your bluetooth headset?

I assume that the phone streams data to the headset (whose session is
hard to dump on Windows mobile) with bitpool = 112, ie. the same it
fails to set in Bluez and I'm saying it gives good results in terms of
perceiveable quality, from which Bluez cannot take advantage due to
its inherent bitpool=53 limitation.

Anyway, I did some additional listening tests (by listening to Bluez
SBC on an A2DP headset). SBC_HIGH_PRECISION alone (without your hack)
only slightly improves quality. Also I finally managed to force higher
bitpool in ALSA (patch attached). This makes further improvement in
quality, at least on headsets that do not choke on higher bitpools.


Regards


--
Sebastian Olter

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