From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pavel Hofman Subject: Impact of SW on USB Audio? Date: Thu, 05 Jun 2008 16:11:49 +0200 Message-ID: <4847F425.7040402@insite.cz> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from server.insite.cz (cable.insite.cz [84.242.84.93]) by alsa0.perex.cz (Postfix) with ESMTP id 4908924633 for ; Thu, 5 Jun 2008 16:12:11 +0200 (CEST) Received: from localhost (localhost [127.0.0.1]) by server.insite.cz (Postfix) with ESMTP id 1F667228A46A for ; Thu, 5 Jun 2008 16:12:11 +0200 (CEST) Received: from server.insite.cz ([127.0.0.1]) by localhost (server.insite.cz [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id yHOcdqnFlWl2 for ; Thu, 5 Jun 2008 16:12:00 +0200 (CEST) Received: from [192.168.1.20] (sara.insite.cz [192.168.1.20]) by server.insite.cz (Postfix) with ESMTP id 05880228A46E for ; Thu, 5 Jun 2008 16:11:49 +0200 (CEST) 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 Hi, Please excuse my non-devel question but the most knowledgeable people read this mailing list. Can user-space software (regular players) directly influence quality of USB adaptive audio output? IOW, how sensitive is adaptive USB to the rhythm of the data infeed to the USB controller? I understand for standard PCI soundcards it is all only about timely delivery of enough data to DMA memory,the card takes care of the rest itself. Do USB controllers shield applications from the rest in the same manner? The adaptive mode is sensitive to jitter of the data stream from the USB controller to the receiver. Can SW players influence the jitter, e.g. by moving the wav files from HDD to RAM disk etc.? I assume a lightly loaded system with no major data delays. Thanks a lot for any insight, I could not google-out any relevant information. Regards, Pavel.