Using battery power to go off the City's power grid

unless you have poor equipment

Your point of view does not help anyone get better sound, it just gets them to spend money, needlessly based on limited data points, limited knowledge of how audio equipment works, and beliefs about what impacts audio that are not supportable.

all inverters do not sound different

I will emphasize a word here to assist in reading comprehension. ALL. That implies that every single inverter will sound different from every other inverter and that is just not true. With most equipment and most inverters (sine wave of decent quality), they will sound the same because power supplies are designed to reject noise/harmonics on the AC line and if they are designed properly, they will.  Some equipment will have poor power supply rejection and will be more susceptible to power line harmonics. That is a poor design.

Again, you will not answer my question......What are you doing on this thread? What is your mission here? To save us all from spending money on Inverters we do not need? We do not need SAVING......We listen on our own and buy the stuff that WE feel makes our stereo better sounding......

You are looking for drama.....if you went to ASR and started saying all this they would just rool their eyes and say...."Well, of course, we already know all that.....you are boring......why don’t you go over to Audiogon where all those subjectivists are and you can really stir the pot there"........and here you are.....just stirring away....every chance you get.

@ricevs I do not answer to you. I will never answer to you. Please attempt to show some maturity.

ricevs and theaudioamp - How about some middle ground? Can we agree inverters need more measurements (such as THD) BUT that does not invalidate what we are hearing? If you can't agree to that please move on.   

@sbayne,

THD is not very revealing of what, if any impact an inverter will have on audio equipment. I am not enamored with pure sine waves because I know what a meaningless goal it is when one considers the equipment connected. I am more interested in high frequency harmonics, and high frequency noise which may cause issues in equipment, noise between line/neutral and ground (if any), etc.

It is not always possible to reduce a complex set of interactions down to a simple number or answer.