My Long List of Amplifiers and My Personal Review of Each!

@mrdecibel

Understood. I will remove my earlier post and forget anything was said .

@thyname +1

Notice he pulled down his post saying as much. Nope found it.

This all makes me think of the MoFi controversy and smile. Audiophiles like to be lied to and like to lie to themselves. It is all I can think of that would cause this behavior. They also seem to defend bullies? Is that some weird Stockholm syndrome thing going on or do they feel they are finally part of the in crowd?  It would make for an interesting psychology paper no doubt.

You clearly hate audiophiles.

This thread is going South and not on topic.  Take it back or it will be closed.  

And that’s exactly what our “friend” on his 14th username is trying to accomplish. And succeeding at it

Lets move on and get this back on track.

WC,

You've been through a lot of power conditioners.  If someone's system is a lower priced system and/or their cabling is not high end (high priced) cabling, then a $15K-$20K stromtank might be desirable, but not in the budget.   For those folks do you have a recommendation?  I had thought you mentioned at one point that it might be best just to do without a power conditioner, since it adds a flavor.  Or, perhaps, you have some recommendations?  

Dave

I have tried quite a few power conditioners and to be sincere, most of them end up forcing you to buy their powercords or else the benefits aren’t maximized.

I have had a puritan labs 156 in the box, new and sealed for about 4 months. I intended to try it but then i became a stromtank dealer didn’t get to try it.

I am not saying power conditioners aren’t worth it, but i hate having to buy more PCs to make them work.

For msb, i like stromtank and audioquest Niagara 5000. For small watt amps, I’d say shunyata omega. The synergistic research Powercell is good but best if used with a full loom of their cables.

Ps audio p20 gets smoked by shunyata Denali V1 which is their older . model....

What I am finding confusing about this proposed $16,000 USD battery for Music Reproduction Systems is as a dealer why wouldn't by Jay a demo be offered? It has been shown by verifiable fact that the videos produced by Jay suffer inherent audible, sonic, sound defects so it does not seem realistic, practical, or reasonable to expect the customer to rely soley and exclusively on the video to arrive at a purchasing decision. I am not in the US so it does not matter directly to me but I am not understanding the approach here.

Sure they can have a demo. Fly into town and come listen 😃

Jay,

I have been pleased with my Shunyata Denali original version.  An Isotek did nothing for me, nor did an isolation transformer.  What specifically was the sonic deficiency of the PS Audio P20?

Ricevs,

If your friend's Giandel inverter plus AmpereTime storage batteries produce a near perfect sine wave, why would the Puritan filter produce a further improvement?  The answer might be that no battery/inverter is perfect, and the filter is required for the finishing touches.  Kinda like the barber who gives a good haircut with the razor, but uses the scissors later for the finish.

Jay,

If this is true, then you would benefit by using your Puritan downstream from the Stromtank, then feed your low power components from the Puritan output.  I still believe that your power amp would benefit from the Stromtank purity, but if you find that the Puritan filter removes macrodynamics from power amps, you could just use the Stromtank on the power amp without the Puritan.  If you think the S2500 can't handle the big Boulder amp, just enjoy the sound from smaller scale music where the S2500 should handle that.  But the S5000 should be able to power everything.

Thanks WC!!

Dave

@cleeds

You should call each power conditioner brand and ask them ? Then arrive at your own conclusions... Nobody has answers for everything. There’s no such thing.

• Why do powercords change the sound ?
• Why do footers make a difference?
• Why does a fuse change the sound ?
• Why are cable lifters important?

The thing is today's topic is focused on the stromtank but don't forget about the topics above. Some things can't be explained folks and I'm shocked that this hasn't been  somewhat"accepted". Also, I'm VERY SURPRISED TOO that most people who spend hours pondering 🤔 and questioning are folks who aren't even buying any of this to begin with. 

It's like me worrying about the neighbors Tesla Plaid that destroys supercars and me saying " the Tesla Plaid sucks because it can't drift and it doesn't have an exhaust note so i don't feel connected with the vehicle or that it is way too quiet , etc etc ". WHY would I care THAT MUCH if i know I'm not buying one or have money to do so??? It's like spending braincells on stupid stuff...i don't understand it. 

The world would be better if we had answers for everything but hell we are STILL trying to figure out how DB COOPER jumped off a plane with $200k in cash and never got caught.

jays_audio_lab

You should call each power conditioner brand and ask them ? Then arrive at your own conclusions... most people who spend hours pondering 🤔 and questioning are folks who aren’t even buying any of this to begin with.

Why would I do that? I have pretty extensive power conditioning already in my system that includes multiple derated 20A lines. I’ve already arrived at my own conclusions - that’s how I got here! You seem to suggest that somehow disqualifies me from commenting. Why is that?

Great points you made WC!   I cling more to the subjective, when it comes to audio.   If it sounds good/better to me, then that's my preference - it's all based upon what "I" prefer.   And I can define the differences in what I hear between different products - based upon my subjective listening.  I am not as worried as to "why" it sounds better.

This is a big issue typically for the measurement and/or scientific and/or intellectual folks.  They'll tell me that there's no way it can be better, based upon measurements/science/logic, etc without even hearing it for themselves.   So, they always disagree with me.  And I disagree with them, because I'm basing it on what I hear.

There will always be that divide.  I don't mind if someone wants to base their audio adventures on measurements/science/intellect/speculation, etc - more power to them.  I don't even mind if they share their opinion.  I just think it's gone too far when they tell me I'm wrong and I have to align with their approach.

I've seen that you experience the same here - folks who tell you your wrong and you have to do it this way or that.  This is about your adventure, and you should do it your way.  I 100% respect that.

Dave

Information for more clarity:

All inverters put out noise and distortion.....that is why they will all sound different from each other and will benefit from further (pure filtering) . The Stromtank and the Exeltech inverters are rated at less than 2% distortion....most of the others like the Giandel are rated at less than 3% distortion. This is not .0001 percent distortion like a Benchmark amp or Purifi amp measures. Distortion.....means noise.....I would think a larger inverter would sound better......probably lower output impedance and bigger power supply. My friend with the Apogee speaker system first used a 3000 watt Goal Zero to good effect......then the 3600 watt Ecoflow sounded better and then the Giandel 5000 watt inverter stomped the Ecoflow to the underground.......I doubt it was all wattage capability.......but I certainly am recommending getting the big Giandel as that is the only Giandel that has actulally been tested in a serious system. However, the 2000 watter might sound as good or even better.......And how does using less battery than the 2 200 amp hour batteries he uses sound? He does not care.....he wanted a big inverter system so he did that. Personally, I would just copy what he did....since his sound is off the charts.

When OCD guy first discovered the Puritian filter he did it while filming a Youtube video....check it out......you can clearly hear the difference/benefit in sound in that clip. He then used a noise meter to test the unit. His non dedictated line measured something like 158. His dedicated line measured 19.9........then he plugged the Puritan into the dedicated line and the Puritian had such low noise that the meter would not register. There are a couple of Youtube videos where the guy that owns Puritian is at some audio shows in the UK and shows the noise of a normal line and then he plugs the Puritan into that line and shows the noise level again....both on a super scope.......the noise with the Puritan can hardly be seen. The Puritan can handle 3000 watts......you can plug power amps directly into it.

The Boulder 3060 is another story....it requires 240V split phase.....hardly any amp on the planet has that requirement.

According to my friend with the Parasound Mono blocks and using power hungry Apogee speakers.....there is no loss of bass or dynamics from either the Puritan or high powered inverters.....Just the opposite....you get better bass and dynamics using the two in series than running directly from a super dedicated line. He has no neighbors so he has his OWN transformer on a pole right outside his house and is located one quarter mile from the transfer station (you drive right by it on the way to his house).....so his dedicated line is super duper.....better than almost anyone.......but it sucks big time.

LifeP04 batteries do not have hazards.......of course any electrcity must be carefully delt with. 12V batteries.....no matter how much current they have.....cannot give you a shock. LifePo4 batteries are rated for at least 4000 cycles.....that would be 10 years of constant cycling.......so, maybe in 15 years you would replace the batteries. If you put 30 cents in a jar everyday then you would have enough money saved after 15 years to buy new batteries......

If you already have expensive dedicated lines and expensive power conditioning then it makes sense that you would find Inverter power something to resist. Especially, if you have spent a ton of money very recently. However, there is always more......life gives us the next opening when we are ready for it. Are you ready for It?

Bottom line is most dedicated lines only provide a direct path of electricity to your gear from the breaker box. They don't really do sh!t else folks. Let's keep it real. 

You still need money for great power conditioners and the hustle of top end Powercords. I'm determined to eventually not rely on expensive crazy powercords. This doesn't mean I'll be using crappy PCs on power amps but I'm done spending 30gs on PCs. The stromtank, for me, leaves me happy and not changing stupid powercord. Yes i still have powercords laying around and collecting dust but I'm gonna list a lot of them soon. 

All inverters put out noise and distortion.....that is why they will all sound different from each other and will benefit from further (pure filtering) . The Stromtank and the Exeltech inverters are rated at less than 2% distortion....most of the others like the Giandel are rated at less than 3% distortion. This is not .0001 percent distortion like a Benchmark amp or Purifi amp measures. Distortion.....means noise.....I would think a larger inverter would sound better......probably lower output impedance and bigger power supply.

No, distortion means voltage frequencies other than 60Hz. It does not mean noise. You are already starting from the assumption that supplying only 60Hz is a good thing and there is nothing technically accurate about that. A lot of our equipment would be a lot happier with 120Hz or 400Hz.

High frequency noise on the AC lines can be bad as it can bypass poorly designed power supplies. Good supplies, like I would expect in expensive equipment will filter high frequencies out relatively easily. For AC low frequency voltage harmonic distortion is relatively benign. In fact, it can be beneficial. It is why PS Audio implements it. The picture below is the current waveform of a typical audio amplifier. Not that it does not look anything like a sine wave. Very high sharp peaks with lots of harmonics. That is with a nice 60Hz voltage input. Those high currents mean higher radiated EMI, more potential for noise to couple to ground, etc. By allowing benign AC Voltage harmonics, the PS Audio units can reduce the size of those current peaks and reduce the higher frequency current harmonics which are in most cases more damaging than any Voltage harmonics. I have no skin in the game. Companies will tell you what they want you to know. I am telling you what you need to know.

@ricevs , with regards to a post filter, something like the Giandel, even though it has a necessary filter to eliminate the PWM, may still pass some high frequency noise. Your post filter could get rid of that. At the price of the Stromtank, I would hope sufficient filtering is built it.

Here is the full link: https://audioxpress.com/article/r-d-stories-future-shock-powersoft-audio-s-amplifier-technologies Look at the section on Power Factor correction. Outside Audio, most switching power supplies now incorporate power factor correction if they are above about 25W. In some product categories, all power supplies at almost any power will. All desktop computers supplies will, but laptop "chargers" still lag. I expect some consumer level audio equipment has power factor corrected power supplies. I have not seen it in high end, hence the high current harmonics.

Bottom line is most dedicated lines only provide a direct path of electricity to your gear from the breaker box. They don't really do sh!t else folks. Let's keep it real. 

You still need money for great power conditioners and the hustle of top end Powercords. I'm determined to eventually not rely on expensive crazy powercords. This doesn't mean I'll be using crappy PCs on power amps but I'm done spending 30gs on PCs. The stromtank, for me, leaves me happy and not changing stupid powercord. Yes i still have powercords laying around and collecting dust but I'm gonna list a lot of them soon. 

I don't think it would be a big secret that I am not a big believer in expensive power cords. Well designed equipment should not need them.

However, putting on my "Expensive power cord" hat, and using the arguments that suppliers of power cords use, the Stromtank will not provide any of the benefit of what a power cord is supposed to do. In theory, or at least in marketing speak, an expensive power cord will shield EMI from being emitted or received from the cords (note my comments about PW audio above), and they will provide a low impedance ground connection between different pieces of equipment (the smart ones at least claim the latter). The Stromtank does nothing to help with either of those advertised benefits. 

jays_audio_lab

most dedicated lines only provide a direct path of electricity to your gear from the breaker box. They don’t really do sh!t else folks.

 

That is completely false. In addition to minimizing voltage drop - which is especially helpful if you’re using large amplifiers - dedicated lines can also help provide cleaner, low impedance grounds.

 

 

That was surely the case in my system, but I think power quality varies a lot between locations. There are so many variables, which may also explain why Stromtank may be the perfect solution for you.I get it that you’re trying to sell a $16,000 battery system, Jay, but we’re dealing with simple facts here.

joke of the day:

Why do objectivists insist on double blind listening tests? Because they are double deaf.......

1. They won’t listen themselves

2. They won’t listen to use telling them that whatever (power cords, inverters, fuses, jacks, footers) have their own sound that is easy to identify......instead, they put both hands over their ears and yell at us "I cannot hear you, please speak louder!!!" as they press their hands tighter and tighter on their ears.......(must give them a headache).

3. then repeat #1 and #2 till you die......gee isn’t that fun!

@ricevs

Most people here probably don’t have a good handle on how AC interacts with their equipment, what the benefit of, or lack of, pure 60Hz is, or even how a power cord could fulfill the benefits claimed for them. In two posts, I provided useful information to help guide audiophiles in their purchasing decisions because as @cleeds mentioned, not everyone’s situation is the same, not everyone’s AC is the same, not everyone has access to the same financial resources, and not everyone is in a position due to time, or logistics to try out multiple power solutions.

Can you please tell me what value your last post had for anyone reading this thread?

Your "information" does not help anyone to know what will "sound best" in their stereo.......just a bunch of gobligook. I would call your "info posts"......just another joke of the day........at least, I am trying some humor......to lighten our sense that ANY of this matters.......none of this is very important, in the scheme of things.

I am done responding to you......I have more fun things to do.  Hopefully, so does everyone else.

@ricevs 

As @cleeds has clearly pointed out, everyone's situation is different. Hence one person's listening report will be, in most cases, totally useless for someone else.  What I have attempted to do, and will do for those who take the time to read and understand my posts, is provide enough information for them to think about what the best solutions may be for them.  I am also in agreement with Cleeds that dedicated lines are a good idea. There is very simple and sound engineering for this. It reduces the potential for noise on the AC supply lines, and it also reduces the potential for noise transfer into the ground.  What I also said about the Stromtank not being in a position to eliminate the advantages of power cords (if there are), is also true. I don't need to listen to every system on the planet to know that no more than I need to diet myself to prove that eating less will help with weight loss. With the right knowledge, some things are self evident.

@theaudioamp 

Ding-ding-ding! We have a winner! Member for a week averaging over 20 posts per day providing sage advice from an expert's perspective. Only, you haven't introduced yourself, you find a way to denigrate audiophiles in virtually every post (which means to "put down"), you don't share what gear you have or don't have and you expect people to exchange with you as if you have credibility?

Either you are the guy who keeps changing his moniker when banned or cornered OR you expect others to respect your audio street cred at face value. You don't have to post on every thread...it isn't a rule.

@ghasley :

Either you are the guy who keeps changing his moniker when banned or cornered OR you expect others to respect your audio street cred at face value. You don't have to post on every thread...it isn't a rule.

Yeah. It’s THAT dude. You must have missed my posts from yesterday 🤦‍♂️

Once I thought this site/thread was interesting; I now think its less interesting, and if there is still interest (to me, I’m careful to say!) its almost as if I’m watching a burning building, soon to no longer exist.

It’s either me (not hard to accept if that’s the reality), or something drastic took place, and I missed it.

Either way, it seems the direction has drastically shifted from a person seemingly reporting on observations to something other than that, and its far less interesting, to me, now.

But, I recognize I matter here little.

I respect theaudioamp’s efforts to inform, but the fact is that there is no technical expert including the renowned Dr. Floyd Toole, who has written anything that correlates distortion measurements with purity/transparency/clarity of sound as judged by good listeners, musicians and non musicians. People respect Toole, but has anyone heard his audio system (if he even has one!) to see whether his vast knowledge has translated into the highest fidelity sound?

Thanks to ricevs for mentioning that all inverters generate distortions, which explains the varying "sound" of inverters. This explains the mystery of how the PS Audio P20 has very low distortion of 0.5% or lower on its regenerated AC wave, which is lower than the Stromtank’s published figures, and yet Jay found that the Strom is the best power product he has heard, and that even the Shunyata Denali was much better than the PS Audio P20. Paul MacGowan stated that his Power Plants are in effect amplifiers, so we are back to the fact known by everyone here that amplifier distortion measurements don’t predict an amp’s sound.

This begs the question of WHAT distortions are being measured? I don’t expect anyone in the entire world to come up with a technical answer that has any relation to sound quality. Are Stromtanks’ higher distortions in one parameter outweighed by lower distortions in other parameters which explain their superior sound quality? But I anticipate getting the most practical info from Jay, who will tell us his ranking order of sound quality from several alternatives.

1. Stromttank 2500 alone

2. Stromtank 2500 feeding the Puritan 156 filter

3. Puritan 156 alone

4. Shunyata Denali version 1

5. PS Audio P20

I would like Jay to tell us the specific sound qualities that characterize his best and worst choices.

Ricevs can do the same with his Goal Zero Yeti 400, with and without the Puritan.

The pompous scientific debates have been going on for 80 years at the professional audio and engineering societies. Every single scientist who spends more time at the test bench than careful listening is an ignorant fool, with incomplete knowledge, but we good listeners can share our experiences and help each other.

Right on, thezaks!

I will say screw measurements soon and just unplug my system from the stromtank and then plug it into the wall outlets... The brain will let you hear the changes rather easy

Right. Now you have a reason to try your Puritan and tell us what you hear.

@viber6 you are trying to equate performance of harmonics in an AC source with harmonics in and audio amplifer as somehow they are related wrt sound. There is no correlation. All sources whether the PS, Stromtank or ricevs Giandel are amplifiers. It should be obvious that your DAC, amp, preamp, turntable, etc. is not a speaker though. The only similarities is just like different speakers can be effected by different amps, the way one piece of equipment behaves with a particular noise, distortion and impedance profile of a particular source will be completely different from another piece of equipment. What improves one setup may have no benefit in another setup or even make another setup worse.

P.s. Floyd has a very good system within the confines of his lifestyle and preferences that makes use of a lot of effective but relatively invisible acoustic features. There are articles on it.  My experience is most musicians do not have very good systems. I have heard that from many others.

There really is no debate in professional audio or in the engineering world of audio. Every scientist and engineer working in the field does far far more critical listening than audiophiles could ever imagine and wrt scientists they multiply themselves by doing studies with 10's of people or more in situations that isolate just their hearing. Making claims based on listening to single systems in uncertain conditions without isolating just the thing being evaluated is the exclusive realms of audio forums.

Nice sound.  What's left is to try the Puritan alone, and Stromtank with and without the Puritan.  My guess is that the ultimate purity is a synergy from the Strom plus Puritan.  Let's see what you find.

The Puritan needs some 7 days to settle in when new.  It’s starts off sounding a tad bright and forced.  After a week it settles in and sounds pure and natural. 

The system is performing at such a high level that it is scary. Some suggested for tubes to be added and others want a turntable in order to see what happens.

If i add tubes, we compromise ultimate transparency and if i add a turntable then some might be against the "popping" sounds and prefer the extreme cleanliness of digital formats.

You all see what I mean? It’s a tough balancing act, but if what you want is ultimate transparency and the absolute honesty, this system has it in spades. It simply can not lie to your ears. Some people criticize the system based on the music which i understand 100% but very few folks pump the brakes and question the song.

Is it the song that sounds metallic?🤔

Is it bright because it is classic rock?

Why does my car stereo sound better when using serious XM?

Most of the music we are used to hearing is optimized to sound great on average systems but an ultra revealing system isn’t going to follow those footsteps. You are paying to "decode" everything that normal systems can’t do; the small nuances, extra bells and whistles in the recording that are left behind.

If you are seeking for a carbon copy of the sound produced by average systems but with more salt and pepper, yes this system doesn’t take you there. That said, one thing i can tell you all is that once you get used to this system and you listen to a less revealing system, your ears will absolutely let you know that you are listening to an inferior presentation. It’s as if your brain let’s you know that there is a lot of stuff missing. The closer we get to the source, the more we expose in the recording but some may not want to hear all recordings for what they are. 

viber6

... I anticipate getting the most practical info from Jay, who will tell us his ranking order of sound quality from several alternatives ...

Unfortunately, in an apparent effort to promote sales of his $16,000 battery system, Jay has dismissed completely the potential value of properly configured dedicated AC lines. It's no surprise that Jay may get improved performance from his batteries if his AC power is a mess, but that info is of no value to those who've already optimized their AC power.

As described previously, my friend has a super dedicated line with his own power transformer outside and is close to the transfer station. When his Ecoflow Pro died he plugged his Puritan back into the wall. He said it was the most horrible soncally backwards thing he had ever done. He thinks that ANYONE still using the wall power is living in the past......way in the past. It was horrible sounding. Now, with the Giandel Inverter it is way, way better than the Ecoflow. The only way to know anything is to try it. Audiophiles are so slow and conservative......most are followers.....waiting for Stereophile to review it and for it to gain traction before dipping their toes in the water. You never know when your life will be over.....(actually it never ends.....so lets say "when you will leave this body")......so, are you going to wait till someone makes a cheaper pretty inverter that is plug and play or do you want to listen to your stereo with such clarity and transparency right now that you cry and shiver and you have to keep lifting your jaw off the floor.!!?? Practically free to try.........

There must be one adventurer on the planet.....NO?......all stick in the muds? Do you want to have fun? Or do you just want to listen over YouTube to someone else’s half a million dollar system playing snippets of whatever music?

If I had the strength and money I would make you all a pretty plug and play $6K inverter system that would do 5000 watts............someone will do this eventually.....but why wait?.....you can do it yourself right now for less than that (less than $3K actually).

When your child is acting real bad you might send him/her to their room to think about what they did.........but when your child is sleeping to long and there is a whole world to enjoy, then you want to go into his/her room and shake him or her to awaken them and encourage them to get dressed and go outside and play.   Well, I am shaking you.....gently.....please wake up.....go outside and play......the sun feels good......the colors oustide are amazing.....you can sing and dance and feel real good out there......it is worth the effort to put your cloths on and arise........arise....the glory is all around you.....forever.

@cleeds It is very possible since Jay purpose built his audio room (the construction was included earlier in this thread) that the power is already on dedicated lines and these observations are in addition to that situation… 

5 dedicated lines... 30a, 30a, 20a, 20a, 30a(220v)

All with 10 gauge wire and aftermarket outlets. 

Just my two cents but I am a believer and user of balanced power conditioners like Equitech, etc. and while they may be priced higher they do make a difference and "clean up" the sound.

If your dedicated lines don't terminate in the same box all sharing the same close ground at your equipment than your dedicated lines are making it worse, not better. Multiple dedicated lines to physically separated outlets with equipment connected to them, and then that equipment connected with interconnects etc. Is the antithesis of proper wiring to lower noise and no viper I don't need to listen to know that.

Jay,

Agree with everything you said today at 9:13 AM.  Yes, you may hear some popping noises from older LP's.  For classical, Mercury Living Presence made the most exciting recordings from the 50's and early 60's, but there is lots of hiss.  But there is so much resolution and information and exciting transients that you can just ignore the obvious noise.  That's an extreme example, and with modern LP's the noise is minimal, so on balance you will hear so much of the music.

Want to thank Jay for bringing up the whole area of going off the grid for your audio system.  The Stromtank units look to be wonderful. 
 

Unfortunately, at the price of admission I won’t be buying one.  Here is a new thread that outlines products made by Blueddi. These are more affordable and do not have that DIY look Jay dislikes.  No Stromtank aesthetically, but a step up from Ric’s nice DIY option aesthetically.  
 

cleeds,

It is obvious that the best road to purity includes all the steps on the way. First step--you have dedicated lines. So does Jay with his dedicated lines plus better outlets. Maybe you went all the way like ricevs’ friend with his own power transformer outside, close to the transfer station. Second step--you found that a great conditioner is still important. But ricevs’ friend found that a great conditioner like the Puritan plugged into his dedicated line was far inferior to the combination of the Ecoflow Pro battery/inverter and Puritan. So the third step is the battery/inverter. It seems like Jay has done it all and found that THE most important step is the battery/inverter. Theoretically, perhaps the perfect conditioner could make the other steps unnecessary. The reality is that all the steps contribute as a team.

If theaudioamp is correct that if the dedicated lines don’t terminate in the same box, there will be ground loop noise. So just get rid of the ground loop noise by regenerating the AC with a battery/inverter, and then use a Puritan or other conditioner to clean the noise from the inverter. All these sources of noise are a constantly changing environmental nuisance. The best dedicated lines and outlets won’t correct this completely. We need to be off the grid, and likely use a conditioner for the finishing touches.

Correction to my post.  The brand of the off grid battery system is BLUETTI not BLUEDDI. 

Goal Zero, Bluetti, Ecoflow.....these are all the same type of thing....they have the battery and inverter inside and sometimes the charger. Their problem is, they are all noisy......because they are so crammed inside they have fans that come on with very little or no current draw. Who wants fan noise in your room?

My friend was using the 3000 watt Goal Zero in another room to isolate the noise....then he got the better sounding 3600 watt EcoFlow Pro unit......that sounded even better.....but again.....was noisy. Then it died (what a blessing) and he got the Giandel system.....and its fan will not come on till you are drawing at least 2000 watts continuous (something no one willl do if you are just powering your stereo).....so the Giandel system can be used close by....and in your room.....and it sounds worlds better than the Ecoflow Pro unit that already sonically beat the Goal Zero unit. I would not touch an all in one unit with a stick.....they are all inferior to separate batteries/inverters..........you can just put a nice covering over the batteries and inverter and it will look fine......use your brain.   Be creative.

Look at the Bluetti site grannyring linked.  The basic 200P model 2000 watt hr is an all-in-one battery/inverter, $1599, 60 lb package.  The next level up is the 300 model 3000 watt hr inverter only, $1899, 47 lbs.  The required separate B300 battery is $2099, 80 lbs.  The package is priced at $3699.  This is the package to consider.  Trouble is, the Bluetti site review are from campers, no reviews of sound quality.  Same for Goal Zero.  The only sound reviews we have are from Tom Lyle, and the experiences of ricevs and his friend, and Jay.  We need more audiophile reviews of these cheap and lightweight products.

At this point, it is looking like the Stromtank 2500 is the way to go for audiophile quality of execution, parts, etc.