phase control on BAT VK pre amps


Does the phase control on the BAT series preamps have any appreciable or detrimental effects on music that is not recorded out of phase? I don't hear any difference with phase light on or off?? Anyone experience different effect?? Also, is it better to put pre in standby mode when not in use or leave on constantly? What's the difference??
wwchange
Hi, I used to have a BAT VK51SE. And I did use the phase control. I could hear it on some recordings. Especially in the tightness of the bass and openness of the soundstage. A lot of times it was just hard to tell...

Do you have a tubed bat pre? If so, I'd put in in stand by, keeps the power supply warmed up and ready...but the tubes off...If you leave it on...won't hurt anything...will just have to repave your tubes more often.

If you have a solid state version, I'd leave it on...unless your out of town or something..
Ok . Thanks for that advice. I have the VK40 solid state unit which sounds great! I will leave it on as you suggest unless I'm going out of town for a few days. Even in standby mode it takes about 50 seconds to warm up enough to use . I Havnt noticed if the sound gets appreciably better the longer it's left on after that. I've actually just gotten the unit so not too familiar with it yet. I used to keep my Pass Aleph P preamp on all the time! Heck, it didn't even have an on / off switch!! I guess Nelson knew what he was doing!!
Thanks
It took me years to finally hear it with any consistency. To me, it sounds like a timing issue. Either way, the difference was fairly small.