The Stromtank is nothing but a low distortion sine wave inverter and battery and charger in a box.....and marked up a million times and made to look good so audiophiles will spend tons of money on it. Have you heard of the Giandel inverters? You can buy a 5000 Watt pure sine wave inverter for $900 (2000 watter for $329) and then add as many Lithium batteries as you need (you also need a good charger....maybe $1-300). If you have a class D system then one 100 amp hour battery will last you all day. These things are amazing. Please see my website for details....no, I do not sell them. Check this out....says it sounds as good as Stromtank for $450.....and I use a modified version of this thang (I cannot afford a Giandel....but will take donations to buy one):
https://www.enjoythemusic.com/magazine/equipment/0119/Goal_Zero_Yeti_400_Lithium_Portable_Power_Station_Review.htm
If you add a Puritan line filter after the Giandel then you get even lower noise.....then add your own ground rod for your stereo and a filtered ground system like Puritan has......you will hear things you NEVER heard before....goosebumps on top of goosebumps.
Or you can spend a TON of cash on a German StromTANK.....he he.....maybe a Panzer in disquise? The only thing you get with the Stromtank......is that when it runs out of battery power in automatically switches to the wall.....Woopie....so overjoyed at that advantage.
Please check out my website for lots of info on Gaindel and Puritan.
As always......please remember that you are loved and adored by God, and your very own self. Enjoy this moment.....it is the only moment that you will ever have....this very moment. Feel the beauty that you are......take time to acknowledge the beauty in each other......we are all magnificient! You are just as beautiful today as when you were first born........Baby yourself.....you deserve it.