Hello Scott! I think it should be like this:
dBu: 1mW / 600 Ohms <=> 0.775V (RMS) => X (dBu) = 20 log( U/0.775) => U (Volts RMS)= 0.775* 10 exp(dBU/20) dBV: reference is 1 V => X (dBV) = 20 log( U/1) => U (Volts RMS)= 10 exp(dBV/20) As a consequence, one can admit the following rule: 1 dBV = 1 dBU -2.2 Note: U (Volt RMS) = 0.707 * U (Volt peak) 0.707 = Square root (2) You can also have a look on: http://www.analog.com/Analog_Root/static/techSupport/designTools/interactiveTools/dbconvert/dbconvert.html regards, Markus. > -----Original Message----- > From: J. Scott Merritt [mailto:[EMAIL PROTECTED] > Sent: Wednesday, July 23, 2003 3:23 AM > To: [EMAIL PROTECTED] > Subject: [Alsa-user] Converting dBu/dBV to volts ? > > > The specs for my VXPocket V2 state that the maximum > input line level is +10dBu (+8dBV). I would like to > design/select a pre-amp that generates an appropriate > "line level" signal. Some messages have indicated that > I will need to use an XLR pad to adjust the level. > > Can someone point me to a reference that explains how > to convert dBu/dBV specifications into "volts" that I > can see on my oscilliscope ? > > Also, I'm not quite sure I understand what I need to > do to generate a "balanced" signal for the XLR input > (3 pins). Seems like I need to run a "standard" > waveform into a transformer with a center tap for > "ground". If so, what impedance transformer should > I use ? > > Thanks, Scott. > > > ------------------------------------------------------- > This SF.net email is sponsored by: VM Ware > With VMware you can run multiple operating systems on a > single machine. > WITHOUT REBOOTING! Mix Linux / Windows / Novell virtual > machines at the > same time. Free trial click here: http://www.vmware.com/wl/offer/345/0 > _______________________________________________ > Alsa-user mailing list > [EMAIL PROTECTED] > https://lists.sourceforge.net/lists/listinfo/alsa-user > ------------------------------------------------------- This SF.net email is sponsored by: VM Ware With VMware you can run multiple operating systems on a single machine. WITHOUT REBOOTING! Mix Linux / Windows / Novell virtual machines at the same time. Free trial click here: http://www.vmware.com/wl/offer/345/0 _______________________________________________ Alsa-user mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/alsa-user
