Mytek Dac going Ac to DC power.

Has anyone tried going 13 volts on their external power supply to DAC+?  I read that this improves the sound greatly, so I tried it and it did. I switched back to 12v since I'm worried about toasting the unit. Anyone know if 13v is safe? I emailed Mytek and it's no surprise they said run 12v. Knowing all to well about liability, even if it can do 13v, they won't recommend it since that's not what is published in their manual. 

What high end supplies did you try, and did they all sound about the same as Astron.?

+1 on the Astron, picked up a used RS-12M on ebay for $71 incl. shipping for my Brooklyn + DAC.  I difference is very noticeable in both my main system on digital and in my small room vinyl system using the very good MC phono section in the Brooklyn +.  Stock voltage is 13.8, but I used internal adjustments to recalibrate the front panel meter and reduce the voltage to 13.  Clearer and more dynamic.  You can also look for model #RS-12A, same thing except no front panel meter.  The Astron website lists all their current models plus distributors if you prefer new.  Also just ordered a used LS-10A (28 volt) to replace my Dell laptop power supply, curious to see what improvement that makes to my digital system per recommendation on this forum.

I own an Original (Non +) Mytek Brooklyn as well as a Teradak 12V 10a linear PSU I used to use to power a mac mini stack.
While Mytek apparently recommend 6amps or so, would my 10a PSU be usable with the Brooklyn or is that just too many amps?