Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760197AbYFLOX3 (ORCPT ); Thu, 12 Jun 2008 10:23:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755762AbYFLOXW (ORCPT ); Thu, 12 Jun 2008 10:23:22 -0400 Received: from ns.suse.de ([195.135.220.2]:53803 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752896AbYFLOXV (ORCPT ); Thu, 12 Jun 2008 10:23:21 -0400 Date: Thu, 12 Jun 2008 16:23:20 +0200 Message-ID: From: Takashi Iwai To: "Vegard Nossum" Cc: "Daniel J Blueman" , "Linux Kernel" Subject: Re: ALC883 recording troubles... In-Reply-To: <19f34abd0806120718g21ddfa3bjbf6f194aa1d3d37d@mail.gmail.com> References: <6278d2220806091259t47c9b070v269da0f5855ef014@mail.gmail.com> <6278d2220806111200g4f802885wfc5f0fd6c0405efb@mail.gmail.com> <19f34abd0806120603q2ddc6654r9562dfea556c2791@mail.gmail.com> <19f34abd0806120648j4f15b762r8e72c348c14b946f@mail.gmail.com> <19f34abd0806120655u75df09bfuaf33f1d54128b0b7@mail.gmail.com> <19f34abd0806120718g21ddfa3bjbf6f194aa1d3d37d@mail.gmail.com> User-Agent: Wanderlust/2.12.0 (Your Wildest Dreams) SEMI/1.14.6 (Maruoka) FLIM/1.14.7 (=?ISO-8859-4?Q?Sanj=F2?=) APEL/10.6 MULE XEmacs/21.5 (beta28) (fuki) (x86_64-suse-linux) MIME-Version: 1.0 (generated by SEMI 1.14.6 - "Maruoka") Content-Type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2845 Lines: 76 At Thu, 12 Jun 2008 16:18:14 +0200, Vegard Nossum wrote: > > On Thu, Jun 12, 2008 at 4:02 PM, Takashi Iwai wrote: > > At Thu, 12 Jun 2008 15:55:45 +0200, > > Vegard Nossum wrote: > >> > >> On Thu, Jun 12, 2008 at 3:52 PM, Takashi Iwai wrote: > >> > At Thu, 12 Jun 2008 15:48:32 +0200, > >> > Vegard Nossum wrote: > >> >> > >> >> The external mic: > >> >> > >> >> Node 0x18 [Pin Complex] wcaps 0x40018f: Stereo Amp-In Amp-Out > >> >> Amp-In caps: ofs=0x00, nsteps=0x02, stepsize=0x4f, mute=0 > >> >> Amp-In vals: [0x00 0x00] > >> > > >> > The input volume is zero. Try to raise "Mic Boost" (if present)? > >> > >> They're already all up. > >> > >> Line In Boost = 100 > >> Mic Boost = 100 > >> Internal Mic Boost = 100 > >> > >> Right after changing all these to max, I've read the value from > >> card0/codec#0 again: > >> > >> Node 0x18 [Pin Complex] wcaps 0x40018f: Stereo Amp-In Amp-Out > >> Amp-In caps: ofs=0x00, nsteps=0x02, stepsize=0x4f, mute=0 > >> Amp-In vals: [0x00 0x00] > >> > >> There doesn't seem to be any difference. Even when changing them all > >> to 0 in alsamixer, this output stays the same. > > > > Weird. What happens if you execute the verb directly via hda-verb > > program like below? > > hda-verb /dev/snd/hwC0D0 0x18 SET_AMP 0x7002 > > > > Yep, this has the same effect has changing the "Mic Boost" control in > the Playback section of alsamixer. > > What I discovered now, though, is that I get a much wider range of > values from the external mic (so playback of the captured data > actually sounds correct). It actually works, but there is still a very > strong DC offset that seems dependent on the level of the "Capture" > control. This offset still makes it unusable for recording, since even > slightly louder noises will clip the samples. > > It also seems that this control is reset each time I start Audacity > (even though the "Mic boost" level in alsamixer doesn't change). But I > guess this unrelated to the DC offset issue. > > Changing the voltage level now (0x21, 0x22, 0x24, with Mic Boost at > 0x02) doesn't change the DC offset, but has the same effect as before > (the values fluctuate, but eventually stabilize at the same level). Hmm, then it's all what I can guess right now. There might be some vendor-specific settings I don't know of. To be sure, try the following git tree (master branch), pull on 2.6.26: git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6.git This contains the patches for the next kernel, and some of them are related with Realtek codecs. Takashi -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/