The effective results of using the 24 bit volume controll is loss of s/n ratio . Using the volume in its upper range is considered safe . I would not use as much as -80 considering the performance of the duet's built in DAC ,it is "24 bit" but noise levels suggest 17-18 bits real performance .
Exactly what's happens when conecting digitally is a bit unpredicable , if it's a outboard DAC the results is similar as using the analog output on the duet , loss of s/n ratio but if the DAC is better than the duet the results will be better . Conecting digitally to a processor or ht reciever ? Here it can be more unpredicable on 16 bit material it could be that nothing is happening as the processor or reciever also has a digital volume controll etc and the net results is similar . But who knows how those algorithms works in the ht processor it could be dithering etc . On 24 bit material it gets truncated by the squeezebox , maybe it is better to have a better algorithm doing it in the ht processor or ht reciever , with proper dithering etc . Also hdcd or DTS or ac3 material would not play properly if you use the duets own volume controll. So if used the digital out I would use the fix volume at 100% setting on the reciever ( which I do ). Note for proper hdcd or DTS/ac3 rendering replay gain can't be used either. For the reason of not having to confuse two volume controlls fixed volume can be good in an analog situation too. But there are people using the Squeezebox directly to power amps with the Squeezeboxserver own volume controll ! This works absolutely fine given that you have proper gainnscaling ,ei the power amps sensitivity is either naturally inmthe proper range or can be adjusted or you use atenuators on the squeezebox output . The small losses in s/n ratio is greatly outweighed by not needing a preamp . As with proper gainnscaling the volume is really really low at low settings and you won't be physically able to hear any problems . This all a bit theoretical , in most normal situations it is unlikely that you can detect any problems from the volume controll . However it is good to have a feel for how it's works so one can what makes most sense regarding the rest of th hifi . For example , in my main Meridian hifi I use "volume 100%" in my kitchen I use the volume controll , but I have adjusted the volume on my active speakers so that I can use rather high volume settings on the squeezebox . The way to do that is to adjust the speaker levels so that 100% volume from the squeezebox is just a little bit to loud for normal use. In short the situation is not that simple that you can say that it always sounds worse to use the volume controll in a squeezebox . It can be worse , it can be undedectable , it can be no difference or it can actually be better in some situations. Situations when it can be positive inprovement to use the volume controll . Direct power amp conection . To high input sensitivity in the preamp or amp you use ( however , passive attenuators would be even better here ). Many DAC's interpolation filters does not handle intersample overs correctly , so on moden overcompressed music turning back the volume -3dB or similar could improve the situation for the DAC . ------------------------------------------------------------------------ Mnyb's Profile: http://forums.slimdevices.com/member.php?userid=4143 View this thread: http://forums.slimdevices.com/showthread.php?t=98989 _______________________________________________ Radio mailing list [email protected] http://lists.slimdevices.com/mailman/listinfo/radio
