Hot off the press: Yggdrasil review

Re the PSA DS, I didn't find fault with the frequency balance (at least in the 20 to 20k range), so no, I don't think that it was specifically designed for bright systems.

Keeping a dac on will do nothing to break it in. Need to pass a signal through it and many are not going to spin CDs 24/7. Just to much time on the transport for many of us. Computer audio...sure.

My experience is different. I find just having a DAC on will do most of the burn in (67.354689%...he he). The current running through most components in a class A circuit is constant. This constant voltage and current will burn in most power supply capacitors (which take the most time to burn in). The signal path resistors, and filter caps, transistors and tubes and especially the output caps in a tube unit will need to have signal run through them to fully burn them in. But even the output caps in a tube DAC will have high voltage on them....helping them burn in without a signal moving through them.

Having a signal go through the DAC while it is on will improve the sound further but most of the burn in can be done by just leaving it on. You need to have a load on the DAC output when burning in and playing music...this way some current is being modulated through the output stage as it has a load to draw some current with. Just keep your preamp or amp off and play music. Your preamp/amp has a load resistance to ground that helps pull current from the DAC.

BTW, this is the same with all electrical components (sources, preamps, amps). When I first assembled my first set of NCore NC400 amp modules and listened I wondered what the fuss what about....not good sound. Then I just left them on all night and 20 hours later listened again and....what a difference. Now I understood how good these modules were. No music was being played through the amps. However, days of playing music through the amp will bring more improvement. So, in the beginning (first 1000 hours) leave the component on as much as possible and play music through it as much as possible. Speaker cables and speakers need to be played for them to break in. There are some speaker cable burn in devices...but they are costly.

Yes indeed I was talking about the signal path which is key to the sound also!