From mboxrd@z Thu Jan 1 00:00:00 1970 From: John Rigg Subject: Re: What does 0dB refer to? (Logitech USB Speakers) Date: Tue, 15 Apr 2008 13:32:38 +0100 Message-ID: <20080415123238.GA2732@localhost> References: <20080411204610.GA32413@tango.0pointer.de> <20080414172839.GA26513@tango.0pointer.de> <4803C78A.3020109@superbug.co.uk> <200804150552.13578.faber@faberman.de> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail3.uklinux.net (mail3.uklinux.net [80.84.72.33]) by alsa0.perex.cz (Postfix) with ESMTP id 031E224702 for ; Tue, 15 Apr 2008 14:23:12 +0200 (CEST) Received: from localhost (78-32-150-178.no-dns-yet.enta.net [78.32.150.178]) by mail3.uklinux.net (Postfix) with ESMTP id 0EB671F669A for ; Tue, 15 Apr 2008 13:23:11 +0100 (BST) Received: from anon by localhost with local (Exim 4.63) (envelope-from ) id 1JlkL0-0000iP-4A for alsa-devel@alsa-project.org; Tue, 15 Apr 2008 13:32:38 +0100 Content-Disposition: inline In-Reply-To: <200804150552.13578.faber@faberman.de> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: alsa-devel-bounces@alsa-project.org Errors-To: alsa-devel-bounces@alsa-project.org To: alsa-devel@alsa-project.org List-Id: alsa-devel@alsa-project.org On Tue, Apr 15, 2008 at 05:52:13AM +0200, Florian Faber wrote: > On Monday 14 April 2008 23:07:22 James Courtier-Dutton wrote: > > The aim of the dB values in the ALSA mixer is this. > > > > For Playback: > > Set all the mixer controls to 0dB. > > Send a sample digital signal from the CPU to the sound card. > > The measured analog signal on the line-out should be the same for ALL > > sound cards. > > Consumer levels are -10dBV while pro audio levels are +4dBu. And you > have to be more specific what to measure. Exactly. > How about this: You do what you want with the consumer boards, and leave > the pro guys alone. Pro drivers are not 'broken' if they don't > implement such a 'feature', they are pro drivers. vote++ John