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

Shifting gears, I want to ask the Bluetti or other battery/inverter owners whether they tried these units on complete systems including power amps, as well as just for the low power front end components.  My theory is that the AC powerline distortions are relatively small compared to the main signal, and they would be a much higher fraction for low power components.  It is likely that the entire system would benefit, but my guess is that most of the benefits would be just using the low powered components on the inverter.

I never heard any hums, clicks when charging and listening with N.E.W amp, Merlin BAM or Rockpals battery pack on dac and different streaming equipment lps. Fan would be on with the Rockpals.

Since I'm more familiar with the UPS world, from experience, standard UPS' (themselves) will give off a mechanical hum, and most always a fan will kick on, when a loss of power is detected and they are called for action. but I've never heard any mechanical clicks emanating from them. Double-conversion UPS's (since they're always on battery power) will typically *always* emit some hum and fan noise, continuously (fans to keep the batteries and inverter circuitry cool). That's why I try to locate them away from quiet recording/broadcast studios, or my personal listening areas. I never hear any mechanical clicking noises emanating from them either. Not sure how many audiophiles use UPS' though.   

@curiosjim - I wouldn't listen while its charging even if it has "pass through" charging since some inverters will "click" like that and many times the fan will turn on. I assume the low hum is also the inverter.  There is no doubt not all inverters are of the same quality even within brands. For instance, I wouldn't buy a Bluetti for home stereo use unless it part of their MAX series. 

@curiousjim Mechanical hum or audio hum?

@curiousjim You may not be speaking to me directly, but just out of curiosity, are you referring to mechanical clicks, or audio clicks?

So what about when the battery is charging, is there any noise?  I tried a couple of similar devices and both had clicks when the charger went on and off and the other also added a low hum.

what is different with this product?

Thanks.

JD

This is just one example of a Battery Room at a Data Center (ie, computer farm). These batteries are for mission critical UPS power. 

Typical UPS Battery Room at a Data Center

@dpop - Great. I don't think there is a limit.

@sbayne Oh that should be fun! I think I'll do that! Thanks for the suggestion! Is there a limit to how many pictures can be posted? 

@grannyring - as you know, I’ve been messing with audio gear for a long time but I had no idea of the amount of RF riding on my AC line throughout the house. Its the same result in every outlet I’ve tried that little Entech on!

@dpop - I’m always amazed of the amount knowledge and experience of individuals in the high-end audio community. THD of 0.3% in a radio station under the broadcast tower is very impressive! I see you just joined Audiogon on August 22, 2022. You should take a few minutes and post your system in the members Virtual System section with a few pictures.

>>>All of my home audio equipment (TV's too) has been on a double-conversion UPS for years now.<<<

Correction, my power hungry power amplifiers are surge protected, but not on the UPS. Only the low wattage consuming front end gear in my audio system is on the UPS. Even some of *that* front end gear is *even more* power conditioned after the double-conversion UPS. My headphone amp (Gustard H10) has a smaller dedicated 500VA balanced AC transformer from which it gets its power from, and my PC tower (yes, I still have one of those) which contains my Audioscience ASI5002 soundcard, also has a dedicated 500VA balanced AC transformer feeding it. I also use a dedicated isolation transformer for my CD players (of which I have two). I have the measuring devices to measure noise floors, and my amps receive a -95 dB SNR signal. In listening terms, of course that is a *very quiet* noise floor. THAT is the figure I pay most close attention to.   

Even though in my previous posts I have put a lot of emphasis on THD; maintaining a figure of 1%- 2% it's not always my numero uno priority. Just like many of you, my ears play a bigger part. For many years I've owned a Fluke 43b (like mentioned above), and was obsessively measuring THD on my AC lines. Since readings in my house were always within the 1%-3% range, I sold it, but I still stand behind the neutral theory, because in the electrical world, there's been so much discussion about it.

As I may have mentioned, I was Chief Engineer for numerous radio stations for over 30 years (try interconnecting 13 studios in the same building, which are all interconnected to each other, full of audio gear, and have an end result of no audio humming or buzzing - it's quite the challenge).

One time I took my Fluke 43b, and plugged it into a power strip which had at least 12 pieces of gear plugged into it, at one of the radio stations I was working at. This rack of gear was about 6 feet from the primary power service entrance for the building (lots of EMI I'm sure), directly under a 340' self supporting broadcast tower (lots of RFI). I was amazed(!!) when the Fluke revealed a THD of 0.3% at/on this powerstrip. In all my years of owning that Fluke 43b, I've never ever found a reading that was under 1%, anywhere, but of all places, in a rack full of gear, at a radio facility, directly under a broadcast tower. Now I think this had something to do with the rack being so close to the service point entrance. My theory on this is that the neutral feeding this rack had a very short distance to travel, and had little chance to inductively pick up noise via that short distance, which may be why it had such a low amount of THD. I was very happy to see this reading, as this rack contained the audio processor for the over the air (OTA) audio, and if I'm feeding AC to this audio processor, which has a 0.3% reading, glory be, all of the listeners of this radio station benefit.  

@sbayne 

Thank you for that most interesting video.  Crazy hearing your local radio station so clearly on your AC line! 

@dpop The setup you're speaking of is pretty much exactly replicates my AC setup!

Speaking of neutrals, recently I experimented with two of my diy power cord recipes. One has exact same number and gauge of wire for neutral and hot, the other has oversized neutrals. While I expected the recipe with equal N and H to outperform the oversized neutral coming out of my BPT balanced transformer based PC, result was quite the opposite. PC with equal N and H being more lightweight, bass shy, along with more hifi/analytical qualities.

I don't know how much this has to do with the way neutral is treated in my dedicated lines, but it is there. First discussion I've seen on the importance of neutrals!

The central and unknown issue is what types of distortions are coming from inverters.  They are substantial, a lot higher than from filtered and grounded power.  Using a Puritan or other filter after the inverter makes sense for a one-two punch.  So we are back to the primitive state of wondering why there may be natural aspects of tube electronics yet with their much higher distortion measurements vs SS.  Back to listening.

Thanks dpop. What you are saying for utility powered AC circuits makes total sense (dedicated lines, balanced power, isolated grounds and neutrals, etc) @ricevs and others have really done the yeoman's work on trying to find a reasonably priced but high-end battery powered solution which is what I'm focused on for now. 

One word; "Super-neutral".

Well ok, it is in fact (two).

Many audiophiles (myself included) consistently focus on earth grounds, grounding, and "clean" power. Yes, that's important, to maintain low noise floors (as earth grounds can also act as bonding conductors, which is also good), but what many times gets overlooked (IMO) are AC neutrals. Many times you can lower AC power total harmonic distortion (THD) by maintaining clean neutrals (and sometimes even oversizing them).

Let's take for example a dedicated 20 amp circuit, exclusively used for audio equipment. If you only plugged in one piece of audio equipment to that circuit, the THD on that circuit would probably be at 1% or lower (a good sign of clean power). Start plugging in more equipment to that "dedicated" circuit (especially equipment with switching power supplies), and the THD on that circuit is almost guaranteed to rise in value. The *neutral* bears the burden of equipment with poor power factors. There is a whole science behind this.

When electrical building engineers design an electrical system for a building, (if they're smart) neutrals, and balancing 3 phase electrical systems, are paid close attention to (neutrals especially). The story revolving around The First Interstate Tower (now called the Aon Center) fire in 1988 in Los Angeles has many times been reported as electrically related. Here's what Wikipedia says about that: "The fire's origin has been attributed to overloading of the building's electrical system by reactive distortion of lighting circuit currents." I'm not sure reactive current was fully understood in 1988, as computers were just starting to be the norm in office buildings, along with electronic fluorescent ballasts. It is rumored that the building had a lot of personal computers in the building, which all had switching power supplies (along with the numerous electronic fluorescent ballasts), which possibly/probably overloaded undersized neutrals (probably because the 3 phase power was not balanced correctly).

Times have changed, and switching power supplies are being built with better designs these days (energy star), and have better power factors (a perfect power factor is 1.0 or 100%). A perfect power factor means the piece of equipment is using all of its power, efficiently. There are however still a lot of switching power supplies (and electronic ballast fluorescent lighting) out there that have poor power factors, and high THD. 

So when establishing (utility powered) AC circuits for audio, have as many dedicated AC circuits as you can, and make sure that each circuit has a dedicated neutral, along with a dedicated isolated ground (no daisy chaining neutrals). I realize this can be costly, and quickly fill up a circuit breaker panel (technical term being Load Center), but it will keep AC circuit THD at low levels, which is the key to maintaining high quality noise free utility AC power.

Personally, besides trying to keep my neutrals clean, I also employ Equitech balanced AC power (Google that), isolation transformers, and Tripp Lite Ultra Isobar surge protectors to keep my noise floors as low as they can be. Good luck everyone.    

That station’s radio tower is a couple miles away so fairly close. Interesting that particular RF goes away when on battery power. I assume my house wiring is acting like an big antennae. I just tried it in a few kitchen outlets and got great radio reception there too! haha

For $40 the Entech is enough for now. The Fluke analyzers, even used ones, are over $500. Good inverters have THD of less than 3%. The voluntary THD limit for US voltage is 5%. So, that might explain partially the result here. But, I agree we must listen to music and not just rely on a cheap Entech or expensive Fluke analyzer.  Measurements are a tool not a result.

https://electrical-engineering-portal.com/essential-basics-of-total-harmonic-distortion

ricevs,

Here's a perspective on how stupid audio expenditures can be.  Is $2K a trivial amount of money for an audio item that you cannot try before you buy?  NO.  If you buy it after your own listening for a week when you are working with a reputable local dealer, and you like the improvement in the sound, then it is worth every penny, even if you spent $10K.  

But $1K buys a medium intensity PEMF (pulsed electromagnetic field) unit which can be used for numerous health problems.  $10K buys a powerful PEMF unit which can heal major neurological diseases like Parkinson's, Alzheimer's, chronic fatigue, cardiac disease, prostate enlargement and others for which mainstream medicine merely uses drugs and invasive procedures.  Since I know you are interested in alternative health methods, I think you will be interested in this.  Read the writings of Dr. William Pawluk, a major expert in this field.  Look at his site drpawluk (dot) com.  

Wanna be happy?  That comes from achieving the best health and well being possible, which is much more valuable than fleeting audiophile satisfaction.  Most sane people who have good but not perfect health are happy, but many audiophiles who are seeking perfection are never happy.  You can have both, and it is necessary to have a perspective on what is really important so you can justify whatever money you spend on both pursuits.

Here's another picture of the Fluke 43B:

Fluke 43B

When you're really serious about power quality:

Fluke 43B/003 Power Quality Analyzer

Even though this model is now discontinued, you can still find them used on ebay. This unit will display the 60 Hz waveform (in addition to many other things), AND, give you a THD figure. With this meter (I've had one in the past), you might be surprised to find out that your home/apartment/condo utilityAC power is cleaner than you think it is. As many of you are already aware, AC line THD is a good indication of how clean your power is. 

@jollygreenaudiophile2 mentioned a flywheel type system. Just in case some of you wanted to take a look at this type of energy storage system, here's one that I'm aware of (BTW, you can click on the link on the right hand side for a tutorial):

https://vyconenergy.com/products/ups/vdc-products/

I believe these are mainly used in data centers (and other broadcast applications) to cover the building load, while a generator is ramping up to full voltage, which will then take over the building load. I've never used one, or been part of a facility that had one, but it looks like they can take the place of many UPS'.

Some of you could skip over all of the hassle of setting up separate components of batteries and inverters by simply purchasing UPS' which contain both of these components all in one package. Many models include metering too. Here's the thing about UPS' - there are typically two types; standard (or line interactive), and double-conversion. A standard UPS only transfers power to batteries when a power outage is experienced. In this situation, one specification to note is transfer time. That is the time it takes for a standard UPS to switch from utility power, to battery power. Sometimes that time can be 10 milliseconds, or higher. In a typical broadcast application (I'm a former Radio Broadcast Engineer), I used UPS' in many broadcast situations to momentarily supply power to broadcast gear, until a generator kicked in (after the loss of utility power) and took over. Sometimes this 10 millisecond (ms) transfer time was not quick enough, so many pieces of electronic microprocessor based equipment would lock up. What a pain. I then began using double-conversion type UPS'. This is a type of UPS that is *always* on battery power, with no transfer time. It sounds like with all of the batteries and inverters you're setting up, you're in a way creating a double-conversion UPS. Lead-acid batteries were the norm with UPS', but now many are utilizing Lithium Ion batteries. Here's an example of a double-conversion UPS:

UPS' come in a wide range of volt-amp outputs (easily converted to watts via website volt-amps to watts calculators). Another added plus of a double-conversion UPS is since it's always on line, it protects your equipment during momentary (and longer) utility power outages. All of my home audio equipment (TV's too) has been on a double-conversion UPS for years now. A word of caution though if you go searching for a double-conversion UPS; make sure to read the fine print. Some manufacturers use different terms for double-conversion. Key words being - no transfer time. 

Cool little toy.  The Puritan is so low in noise that it won't even measure on that thing......but a single measurement does not mean that much by itself.  I am going to change the outlets and inlet and wire on my friends Puritan on Wed. because people have already done this and said it "sounded better"......the different jacks and wire will not make it measure any different......most things that make for better sound cannot be measured.  You could have two inverters that measure quite similarly but sound radiclally different.

Thanks for sharing on video.  Fun tool to play around with for $40. I have multiple conditioners on 2 systems and 2 solar battery (48v AGM) backup outlets with different inverters that I can use it on to compare results.  Should be fun to hear the  results.

Ok, here are results of the Entech Wideband Power Analyzer I recently got to check out the noise on my house power lines v. the Bluetti AC200MAX. Its rather humorous but remarkable! I assume if I got a Puritan 156 it would take the noise reading down to zero.

First paragraph.......Do you really think I am that stupid that I did not already know all that? Do you really think that would be easy to do and something I would want to do? Most of what you "mention" is already known....you like to reiterate things over and over and make it seem like you are super knowledgeable. But now I see why you want me to do it.....because:

In the next two paragraphs......you show your huge fear of loss. Look at the words you use....."I am prudent, minefield, financial ruin, don’t count on money back, tough economy, lose all money spent". Such drama!!!! You don’t trust the universe....This is sad. I feel sorry for you. If I had the money a Gaindel 5000 would be here in a minute.

You cannot take your money with you to the other side. Your life can be over in a millisecond. You can enjoy better sound or whatever you want in this NOW.....you can enjoy your life NOW. There is only the NOW.....ALL the love and joy and happiness that has ever existed.....exists right NOW. Most people are asleep to how alive and loved they are. Please wake up and enjoy the beauty that you are, everyone is, and the possiblilies of what you can do with your stereo and every other part of your life. YOU ARE LOVED. YOU CAN let go of your fear of loss.....the Universe LOVES you. Stereo is not really that important in the scheme of things.....but if you put energy into it....why not make it bliss and fun and play.......It does not have to be a struggle to "avoid financial ruin".........lighten up.....hug yourself....hug someone today.....go make someone feel good. Buy an inverter.....have fun! I AM Listening to the words I write. Truth applies to everyone....including me. I WILL be more trusting today. For I AM LOVED....I AM DESERVING.

I love words....I just now looked at the word deserving.......DE (of or about) SERVING.   When you feel loved....you feel grateful and you naturally want to give it to everyone......you want to SERVE.

I only mentioned that you get the G 2200 so you can learn firsthand what the benefits of your mods (Wonder Caps and possible other tricks you have) would be for the G 2200.  If Oeno is intrigued with your mods, he might be interested in your mods for his G 5000.

I have plenty of money, but am prudent because high end audio is a minefield of many ways to financial ruin.  Even after careful research, it still is a minefield unless you listen for yourself through a friend with mutual interests.  You listen in each others' systems, and he lets you borrow an item for a week so you finally learn the truth in your own system.

Don't count on money back guarantees from a company on the other side of the world.  I still can't tell the country of manufacture for Giandel.  It is a tough economy with many delays due to supply chain disruptions.  I go into this project with the possible outcome that I lose all money spent, at best 50% assuming someone from this tiny audience will buy my stuff, but then he will know that I don't like it.  I can afford to lose $1-3K on all this. So I get the best known system (A-time/Giandel 5000) at this point.

You want to know how a 2200 watter sounds versus the 5000 watter?.....you buy them both and compare.....You have the credit to do that ($1300)?  or are you as money poor as me? (remembering that you can get your money back on either or both).

ricevs,

Thanks for links to Oeno's comments.  He has good musical insights and describes the benefits of his Giandel system in a useful way.

You will want to get a Giandel for yourself, maybe a smaller 2200 if that's what you can afford.  Go to Oeno's place, and A/B it with his Giandel 5000, using his same batteries.  Then put Wonder caps on yours, and you both can listen and evaluate.  But it might be risky to take his 5000 and modify it, since he is very happy at present, and there is a chance that he has slightly different sonic tastes than you.

Viber,

I have never heard a Giandel Inverter.....I KNOW nothing about how is sounds......but I trust my friend and know his system (which is incredible). Here is what I will tell you......the Giandel will give you everything you ever wanted and more........or it won’t. he he

The PS Audio uses a generated sine wave and a power amp to do inversion....very different from the "normal" inverters. I don’t know the technology.....but looking at the schematics it is very different from a "normal amplifier". Actually, it does not matter about terminology.....of what does what.....What matters is the sound. Even Jay on his forum likes his $27,000 Stromtank inverter better than the $10,000 PS Audio thang (whatever you want to call it).

The quality of the inverter is based on infinte things. When I was modding the Exeltech inverters back in the 90s.....I changed the output filter cap from a Panasonic cap to a Wonder cap and the sound was more pure.....a gazillion things make for sound differences. The inverters out there are not made by audiophiles who listen to every resistor, wire, inductor, cap, damping, etc. etc. They are made to function well for their intended use......So, if you find one that is exceptional sounding for audo....it is a find......The Giandel seems to be the one for NOW.....only NOW....for tomorrow it may be tossed out for the SUPER DUPER lastest one......This game has just begun.

"My musical experience and knowledge exceed anyone you have ever met in your long life" Wow, someones ego is out of control. How do you know this? And WHY would you state that? Do you want to be seen as super important and all knowledgable? When you really love yourself deeply.....you also deeply love everyone. You would never try to make your self superior to others.....We know who is most loving....by their love. No one needs to brag that they are loving.

You are so beautiful.....you never need to brag or put on a display....you simply be yourself.....and the "yourself" that is real wants to always be of service and love everyone because that is what is REAL and gives the most happiness to everyone.

"I’ve learned that people will forget what you said, people will forget what you did, but people will never forget how you made them feel.”~ Maya Angelou

Please, love one another.....make someone FEEL good.

A beautiful woman was talking to me as I was leaving the property here a couple of days ago. She called me "sweetheart".........As I drove out in the street, I was glowing.....I kept saying to my self....."she called me sweetheart".........she made me feel good. So, my sweethearts....have a great day, and a great life...YOU are loved.....pass it on.

@ricevs Good that you can hear the failings of the interters you are testing.

About your comment on PS audio, I don't understand what you are saying or else you don't.  Inverting is changing DC to AC.  The PS audio rectifies the DC from teh wall and the converts it back to AC, the definition of an inverter.  

Are you trying to point out some other subtlty?  

But I say it is the quality of the inverter,  the quantity of amperage, and the low output impedance, that makes a quality power supply expensive.

Jerry

ricevs,

Please just answer my simple questions.  I know how to interpret your direct answers.  If you tell me that the Giandel is a soft sound like the Yeti, I won't waste even $2K trying it out.  I am perfectly happy with my present system not to bother with the extra considerable floor space requirements of batteries/inverter.

Don't school me on life, experience, etc.  My musical experience and knowledge exceed anyone you have ever met in your long life.  I respect your technical knowledge, so just answer my questions, please.

I'll read Oeno's account on WBF, thanks.

Again with the clarity/resolution verus warmer/rolled off addiction game. It is not one game....It is not one way.....

You will only know what better is by trying one and listening......then you will know.. I can tell you a bunch of words (you like words) but words are not experience. When you get your Giandel (maybe in few years of talking about something you know nothing about).....and you listen.....ONLY then will you know what "better" is......but then again, you might find it "worse".....and this is why you need such hand holding.........."That jump off the curb really is small" says your mother....."I will even hold your hand." God, life, your mother, all of us are holding your hand. You will be safe. Trust the universe....trust your experience....but in order to have experience.....you have to JUMP!

So when is your Giandel arriving so you can listen and tell everyone what you hear? Or, are you just going to keep asking questions and making comments? Do you really want to know something? Knowledge is experience. I can describe the taste of chocolate all day long and you would still know nothing......You put a small piece in your mouth and you instantly KNOW..

Here are some words you all might like: The guy Oeno is the guy with the Giandel system....please read his comments: especially posts #56 and #61 on the next page

https://www.whatsbestforum.com/threads/rada-precious-one-phono.34842/page-3

ricevs,

I still don’t know what you mean when you say the Amperetime/Giandel is "better" than the Yeti and Ecoflow. To me, "better" means more clarity/resolution in the entire freq range, but to euphonically oriented listeners, "better" means warmer and rolled off, etc.  If you say the Goal Zero sounds a little soft compared to the Bluetti you tried, I would probably prefer the Bluetti.  You say the Bluetti is "zippy" compared to the Goal Zero, but Bluetti owners here have not found them to be "zippy."  More advanced Bluetti options put them in a similar price range as A-time/Giandel.  Did your friend A/B these Bluetti's to his present A-time/Giandel?

This discussion is not at all like a typical discussion coming from Jay, where he claims that expensive invariably means better.  We are out to find battery/inverter solutions at 5-10% of the price of the Stromtank 5000, the only S-tank unit which can handle an entire high power system.  If Tom Lyle found the Goal Zero Yeti 400 sounded identical to the Stromtank 2500, that implies that the S2500 is a little soft, like the Yeti 400.  Is the A-time/Giandel more like the Bluetti for resolution at all freq?

@rudyb This is exactly what my N.E.W. DCA66 class A ss amp did, and this all back in late 90's!  It was nice to have an off the shelf all in one package offering, thought I would have seen more offerings in such a package over the years.

Why not use a 36 or 48 V battery and connect it directly to your amp's internal diode bridge rectifier, bypassing all troubles from 110/240V, inverters and what have you? It'll be a lot cleaner, and cheaper.

I use the Yeti 400 for the whole system...the front end components are hardwired into the inverter and I plug the power amp into it with a connector.......that is why I could not do the full system on both.  Who would A/B a $400 all in one with a $2800 giant Gaindel system?  No one.  As I have stated over and over again.......the Yeti 3000 was beaten by the Ecoflow Pro which was annihilated by the Gaindel system.  I have no idea how the Yeti 400 compares and who cares.....it is too small to use for most people and has a noisey fan (which I made silent by removing most all the casing).  My friend uses the Giandel sytem and used the Yeti and Ecoflow on his entire system.  Get out of your head!!!!  Just do it!!!!!

The Entech will tell you something but not much.  People are already modding the Puritan 156 (which would not even measure with the Entech). and getting better sound (and that better sound has NOTHING to do with a measurement).  We are talking better jacks, better wires and Fo-Q treatment.  I will be installing burned in Furutech outlets and inlet and better wire on my friends Puritan 156 next Wed.  Most things that make for better sound CANNOT be measured.  An inverter that measures lower with the Entech may sound way worse than one that measures better......this game is complicated.

ricevs,

Too many variables between the compromised Bluetti AC200P and the Goal Zero Yeti 400 with its woodblocks and PPT.  I thought you were using the Yeti with your front end only, not with power amps.  The most meaningful A/B you can do is between your Yeti 400 and your friend's Amperetime/Giandel, both used only on his front end.  Your Yeti 400 can't handle the power amps, unfortunately.  But maybe you remember the Yeti 3000 which can handle the entire system, and how it compared to the A-time/Giandel in your friend's system.  How did the Yeti 3000 and A-time/Giandel compare for just the front end, and the whole system, for bass and the other sonic aspects?

I have an Entech power line noise analyzer arriving on Monday. OCD Mikey used one in his videos regarding the Puritan conditioner and they are fairly cheap.

@ricevs - Too bad it was actually the Bluetti AC200P which uses their older inverter design that according to Hobotech is much noisier than their current MAX series of inverters. The control software is also different. Anyway, I've been looking at your webpage again (great info there) and will probably build a Giandel 5000 system.  

The Bluetti I have here is the AC200P not the AC 300 which is an inverter with out battery......this one has the battery.

OK, used the Bluetti on the amp (that draws 35 watts at idle).........the bass was a little better than the Goal Zero but the imaging was not nearly as real.....you can see the space of the recording venue and each instrument is in its own space more with the Goal Zero......The Goal Zero sounds a little soft......the Bluetti sounds more like the zippy wall sound. When listening with the Goal Zero you want to turn it up 2 db and then it is goosebump heaven. time The Bluetti is sitting on the floor and the Goal Zero up on some wood blocks. The Goal Zero also has a PPT AC thangy plugged into its spare AC outlet. Really the test is mostly meaningless. By having the amp plugged into the Goal Zero you are getting more noise interaction from the amp to the other components.....so, I should have a second Goal Zero just for the amp to be fair....and also a PPT thang plugged into the Bluetti and also have it off the floor.....everything makes a difference.....But, I will say I did not want to go back to the Bluetti after hearing the Goal Zero again......If this baby denuded Goal Zero sounds this good what the heck does a 5000 watt Giandell sound like? I want to know.....Maybe I will start a go fund me page and you guys can buy me one.....he he.

There are no specs for any inverters output impedance.....don't make stuff up...,..just listen and report what you hear......this is what we all want....real knowledge.

Actually, live unamplified bass in the appropriately sized room or hall is delightful because of the many harmonic overtones which go up to HF.  Take a French horn which has bass, although not as deep as a tuba.  James Boyk has an essay called "Life above 20 kHz" or something like that.  He showed that the French horn has significant energy up to 9 kHz.  When you hear the French horn up close, it has tightness of bass, as well as midrange/HF.  Bass by itself isn't tight, but the perceived tightness is from the much higher freq overtones integrated into the total sound of the instrument.  

Bass instruments in various sized rooms have different tonal balances.  The large piano in a small room sounds awful, because the walls reinforce the bass more than higher freq, creating a bass dominant heavy sound.  The same piano on a large concert stage sounds lighter in tonal balance, with less perceived bass than in the small room.

The Goal Zero 400 is a special case where the high impedance is another factor to its detriment of bass.  Perhaps larger inverters with lower output impedance is a big factor in explaining their superior sound.  But impedance is only one factor.  We can look up the impedance of the larger Yeti 3000, and compare to Giandel 2200 and 5000.  There are probably other factors responsible for the superior sound of the Giandels, and whether the G 5000 is superior to the G 2200.  Any of these units are a tiny fraction of the Stromtanks, so that's why I am going for the G 5000 which your friend vouches for.

Viber,

The bass using the Goal Zero Yeti 400 is looser but not fuller...there is the same exact amount of bass as with the wall. It has relatively high output impedance compared to big inverters so makes sense that bass would be affected negativiely (sounds slower). You seem to have one opinion of everything....."something is either detailed, tight and accurate or its loose bloated and slow". This is far, far from the truth of things. There are a million shades of grey and many sonic factors are independent of each other. You can have loose bass that is less, the same or more than tight bass.....tight bass can be small, medium or large and full....yes, listen to some bass playing live......depending on the room, instrument, whether it is amplified or not....bass can have infintie descriptions. IT IS NOT ONE WAY......expand your mind.......it it infinite.....However, we ARE ONE......but many are the ways and names.

+1@ricevs I've been working at noise reduction for years what with all my battery experiments, dedicated ac lines, conditioning, and now with streaming.

Noise reduction in streaming is so linear to ac cleanup in general sense. You are describing the exact qualities I hear with my present setup. My streaming and cd rips no longer sound like digital, simply sounds like performers in room, and better than my vinyl setup due to higher resolution/transparency.

If battery power could outperform my rather intensive ac cleansing this would be comparable or superior to major component upgrade. At this point trying to decide if my next move will be another network filtering device or battery power.

ricevs,

I agree with much of what you just said.  My main question was about the bass from the Goal Zero.  Comparing to wall AC, Is it looser and fuller, in other words quantitatively greater but qualitatively worse as with old school tube amps?  Is it tighter but quantitatively less?  I assume you found that aside from the bass, the Goal Zero is more accurate in midrange/HF?

Still, noise reduction easily occurs when you roll off HF.  With crude Dolby noise reduction, I remember HF hiss was nearly eliminated this way, but information in the rest of the range was severely destroyed, creating lifeless sound.  The sonic effect is its own type of distortion.  So noise is not synonymous with distortion.  

We want LIFE to all the instruments.  For wind instruments, you want to hear the nice tone, but also the mechanical sounds such as keys, valves, spitting.  Some people seek to get rid of these extraneous "noisy" sounds, but all these sounds are part of the complete sound of the instrument and must be revealed although not exaggerated.

Great post, @ricevs - many great points there, and you reminded me of a few more things I've been wanting to try.

Regarding what you called a "zippy" sound:

I'll add to that a pronounced sound of "air" and other micro details.  It is impressive, and even seductive, that a system can reproduce and present that "plankton" (for lack of a better word) in a recording - and good systems can do this without it sounding harsh or fatiguing.  It's very cool, and my system has done that.  But in my opinion, it is not natural if you compare to hearing a live performance. 

On my own journey, with each successful change to lower noise in my system - that "zip" and air and pronounced plankton is not as noticeable.  It's there, but not a main player anymore - just supporting the artists and instruments.  

My experience has been that lowering/removing noise has increased realism which creates more frequent emotional responses to the music - for me.  Natural, organic realism is what I respond to most.  And being able to have that emotional response on demand is my goal.  

Happy listening to all.