Andrew,I should add that the problem is also present in the original version of Vista. One of the Microsoft people said he thought it may have been fixed in SP1 but it wasn't.
Jeff----- Original Message ----- From: "Andrew Elder" <aelder@xxxxxxxxxxxxxxxx>
To: <wdmaudiodev@xxxxxxxxxxxxx> Sent: Friday, September 05, 2008 11:44 PM Subject: [wdmaudiodev] Re: Sample Rate Converters
Jeff,Thanks for the additional input. Those plots are interesting. I guess our customers can't use the SRC in Vista SP1 for recording.- Andrew Jeff Pages wrote:A while back I ran some capture tests on Vista (SP1), using a 24-bit AES/EBU 1kHz tone source and looking at it with Cooledit's spectrum analysis for the different combinations of Vista audio engine sampling rate (44.1kHz or 48kHz) and Cooledit recording rate (again 44.1kHz or 48kHz). My results are at http://www.innescorp.com.au/uploads/downloads/other/vistacapturesrc.pdf .In the two cases where Windows inserts its sampling rate converter, there are some pretty high-level artefacts. This doesn't happen on render, only on capture.Jeff----- Original Message ----- From: "Andrew Elder" <aelder@xxxxxxxxxxxxxxxx>To: <wdmaudiodev@xxxxxxxxxxxxx> Sent: Friday, September 05, 2008 5:07 AM Subject: [wdmaudiodev] Re: Sample Rate ConvertersSome test results. Playing a 1 kHz sinewave through a 48 kHz AES/EBU output I get: XP SP2 48 kHz -96 dB THD+N 44.1 kHz -85 dB THD+N 32 kHz -85 dB THD+N Vista 48 kHz -133 dB THD+N 44.1 kHz -133 dB THD+N 32 kHz -133 dB THD+N so, Vista is much better than XP in this regard. On the record side, recording from a 48 kHz input I see XP SP2 48 kHz -97 dB THD+N 44.1 kHz -86 dB THD+N 32 kHz -84 dB THD+N VistaKept getting record format errors. Couldn't get the recorder to work correctly.- AndrewAll measurements made using a dScope Series III and ASI5044 audio adapter.****************** WDMAUDIODEV addresses: Post message: mailto:wdmaudiodev@xxxxxxxxxxxxx Subscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=subscribeUnsubscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=unsubscribeModerator: mailto:wdmaudiodev-moderators@xxxxxxxxxxxxx URL to WDMAUDIODEV page: http://www.wdmaudiodev.com/****************** WDMAUDIODEV addresses: Post message: mailto:wdmaudiodev@xxxxxxxxxxxxx Subscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=subscribeUnsubscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=unsubscribeModerator: mailto:wdmaudiodev-moderators@xxxxxxxxxxxxx URL to WDMAUDIODEV page: http://www.wdmaudiodev.com/****************** WDMAUDIODEV addresses: Post message: mailto:wdmaudiodev@xxxxxxxxxxxxx Subscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=subscribe Unsubscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=unsubscribe Moderator: mailto:wdmaudiodev-moderators@xxxxxxxxxxxxx URL to WDMAUDIODEV page: http://www.wdmaudiodev.com/
****************** WDMAUDIODEV addresses: Post message: mailto:wdmaudiodev@xxxxxxxxxxxxx Subscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=subscribe Unsubscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=unsubscribe Moderator: mailto:wdmaudiodev-moderators@xxxxxxxxxxxxx URL to WDMAUDIODEV page: http://www.wdmaudiodev.com/