Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761477AbYFLOSY (ORCPT ); Thu, 12 Jun 2008 10:18:24 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751355AbYFLOSP (ORCPT ); Thu, 12 Jun 2008 10:18:15 -0400 Received: from po-out-1718.google.com ([72.14.252.157]:49290 "EHLO po-out-1718.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750956AbYFLOSO (ORCPT ); Thu, 12 Jun 2008 10:18:14 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:cc:in-reply-to:mime-version :content-type:content-transfer-encoding:content-disposition :references; b=BKvX40hOdtSabfCHQaTY+xFvFwf6sbIL/PmCWTPV/wGdpF9ArJ3XB3tNCpqTbbT387 ypHOyv1sUF6ANwSZZRbFjW60WoqmTfegTalJlnnKUEWh4zeAzLSvUZGMpIvgh8wVyAXP 0c51HI3vFSo/vHn3tZeRFRwOqaW44a7/qn5U0= Message-ID: <19f34abd0806120718g21ddfa3bjbf6f194aa1d3d37d@mail.gmail.com> Date: Thu, 12 Jun 2008 16:18:14 +0200 From: "Vegard Nossum" To: "Takashi Iwai" Subject: Re: ALC883 recording troubles... Cc: "Daniel J Blueman" , "Linux Kernel" In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <6278d2220806091259t47c9b070v269da0f5855ef014@mail.gmail.com> <6278d2220806111200g4f802885wfc5f0fd6c0405efb@mail.gmail.com> <19f34abd0806120603q2ddc6654r9562dfea556c2791@mail.gmail.com> <19f34abd0806120648j4f15b762r8e72c348c14b946f@mail.gmail.com> <19f34abd0806120655u75df09bfuaf33f1d54128b0b7@mail.gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2573 Lines: 70 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). Thanks for the help. Vegard -- "The animistic metaphor of the bug that maliciously sneaked in while the programmer was not looking is intellectually dishonest as it disguises that the error is the programmer's own creation." -- E. W. Dijkstra, EWD1036 -- 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/