08-18-2022 Post does not mapped to Knowledge Tree drdna San Francisco, California Posts 526 Joined on 10-29-2005 Post #: 1851 Post ID: 26876 Reply to: 26875 All compromises Like anything else in electronic design, it is all about compromises. No resistor is an ideal resistor and no audio circuit is an ideal audio circuit.  I remember when Meridian Audio came out with their active digital speakers in the mid-80's, and I have to admit they sounded better than a lot of other speakers, even though digital has never been to my taste. In certain circumstances -- and it sounds like you are in those circumstances, a DSP is a reasonable solution that may improve the audio quality. FWIW, I had excavated and installed a dedicated grounding rod at my old house for my audio system, but at the new house, it has not been necessary. Ultimately, there are a lot of solutions out there, and the key is knowing if the problems you are encountering in your audio system require a particular solution. Adrian

08-19-2022 Post does not mapped to Knowledge Tree rickmcinnis Posts 60 Joined on 10-18-2010 Post #: 1852 Post ID: 26877 Reply to: 26876 A thousand ways to skin a .... dog? If only we all could succumb to the realities of compromise earlier in life instead of thinking there is actually a Holy Grail Perfect Solution to any problem.  Audiokooks would be much happier if we would. Kind of like polarity - no one really knows which way is best but there is usually one way that is better sounding.  There is no need to know why one way sounds better than another. I was a purist and swore I would never use PEQ.  Oh, well, live and learn. My 21 KHz blip disappeared last night and since we were having a cool evening in north Georgia I guess my blip is due to the air conditioner.  Never occurred to me before. Only place it could invade the system, I would think, is through the ground wire. I have been wanting to disconnect the ground wire and let the inverter float and hear what happens.  Sometime this weekend. Maybe a ground rod is not needed at all?  Will be interesting to see if the blip re-occurs with the ground wire disconnected.

08-19-2022 Post does not mapped to Knowledge Tree Paul S San Diego, California, USA Posts 2,658 Joined on 10-12-2006 Post #: 1853 Post ID: 26878 Reply to: 26877 Ground and Broadcast Noise About any electric motor can be heard through a hi-fi, including furnaces, ACs, washer, dryer, refridgerators, dishwashers, etc. Isolation efforts include dedicated AC lines with home-run neutral and ground wires. I've never tried one, but there are plug-in "noise supressors" for refridgerators. AC regenerators are known for spreading noise through their own wires to other components, also through the air. Physical distance from susceptable components helps the latter. The neutral and the "safety ground" "should be" tied together inside the component, ie., star grounded. However, it might be that current hangs around in a component, and noise "rides" the charge. In such a case, a ground-only bleeder can often route the standing charge to a ground with a very low resistance. If it works, it works. If not, not. Paul S

08-19-2022 Post does not mapped to Knowledge Tree drdna San Francisco, California Posts 526 Joined on 10-29-2005 Post #: 1854 Post ID: 26879 Reply to: 26878 Different AC circuits in the home Paul, It has also been my experience when dealing with the PurePower that it was sensitive to which circuit from the main breaker that it was plugged in to -- ultimately why I moved to a dedicated line. It is worth experimenting having the stereo connected to different circuits regarding noise. In my listening area, I had reasonable access to plug the PurePower in to three different circuits; and one of them was considerably less noisy that the other two. Adrian

09-13-2022 Post does not mapped to Knowledge Tree rickmcinnis Posts 60 Joined on 10-18-2010 Post #: 1855 Post ID: 26880 Reply to: 26878 More experience with the inverter So after a month I continue to enjoy what the inverter does. I have found that the time one gets from 400 Ahs with the inverter's meter showing 640 watts usage is about 1.5 hours - you could get two if you let the batteries run down further but I figure this is not worth the strain on the batteries. I am not a marathon listener but that is a little too short a time.  Of course one could attach the charger.  I have not listened to music with the charger attached so I am not sure how seriously this would affect things.  I got a charger from POWERSONIC which is almost quiet even with the fan on and vastly superior to the DeWalt one I started out with. One of these days i will leave the charger connected and listen. I have decided to get another pair of batteries.  Having to build a new table for the right side amplifiers to fit them.  Will be first half of October when they can be added.  So then one has a real lummox of a power supply but still far cheaper than doing what Fremer did for his AC - which was probably the most interesting thing he has ever done in my unhumble opinion. I continue to think this has many merits.

09-13-2022 Post does not mapped to Knowledge Tree Paul S San Diego, California, USA Posts 2,658 Joined on 10-12-2006 Post #: 1856 Post ID: 26881 Reply to: 26880 Great, But What About... What about the extra 30 dB you said your tweeters get at 22k Hz? And how far did you get and where did you wind up with the dedicated ground? Best regards, Paul S

09-13-2022 Post does not mapped to Knowledge Tree rickmcinnis Posts 60 Joined on 10-18-2010 Post #: 1857 Post ID: 26882 Reply to: 26881 Took me a moment to realize what you meant about the 30 dB That spike went away. Did not seem to have anything to do with lighting.  Completely mysterious - it just went away and has not returned. I have not done anything with the ground rod idea. I did listen with the ground wire unplugged - a plug with just a ground wire into a socket - and heard nothing at all so I cancelled the ground rod installation. I am starting to think, after looking at battery usage calculators - that I may have a defective battery.  Seems the internet calculators tell me I should be getting far more usage from a full charge than I am getting based upon 400 Ah and 640 watts usage.  The 640 watts is constant, per the inverter's meter. You are far more knowledgeable than I on these matters - do you think 1.5 hours from full charge to 11.6 volts sounds right for 640 watts continuous usage?  There are no ups and downs since these are class a amplifiers.  Could that alone make a difference? This afternoon I will have to measure them separately. Always appreciate your comments and advice.

09-13-2022 Post does not mapped to Knowledge Tree Paul S San Diego, California, USA Posts 2,658 Joined on 10-12-2006 Post #: 1858 Post ID: 26883 Reply to: 26882 Advertising vs. Usable Power I have a long story about battery output and life not coming close to manufacturer's  promises, but I will not tell it. Suffice to say, it may well be that you have a defective battery, as it happens all the time; or, it may be that your batteries don't do as well as advertised; or, your charger might not be optimal for your batteries. Ohm's Law helps with figuring out how many Watts at how many amps your batteries "should" deliver. But, of course, you usually get less, if only because everything is not "optimal", but it takes place in the real world. I can say, I would not be happy with 1.5 hrs. listening time. What, again, is the battery Voltage when you stop charging it? Paul S

09-13-2022 Post does not mapped to Knowledge Tree rickmcinnis Posts 60 Joined on 10-18-2010 Post #: 1859 Post ID: 26884 Reply to: 26883 Starting at 13.5 volts I was using a DeWalt charger that would take the batteries to 14.something which of course fell quickly when the amps were turned on.  That one was a 30 amps charger the one I am using now is rated at 55 amps and goes through three modes of charging finishing with a maintenance mode which never turns off.  The DeWalt would turn off for some unknown reason in maintenance mode. The charger seems to have been made for use such as mine.   It looks like  a serious piece of gear and not something prettified for the consumer market.  I can ask them if it is possible to raise the charging voltage but I got the feeling that 13.5 is a good charging voltage.  I am confident the charger is not the problem (famous last words!).  Confidence can get one in lots of trouble. I got the batteries from AMAZON and it looked like they simply dropped them off of the back of the truck.  The packing was very good and there was no damage to the appearance of the battery's cases or the packing material - one would not think that internal damage had occurred but I have no way to know about that.  Obviously one of them is working correctly! If one of the batteries is not doing its share of the work that could explain what seems to be a serious difference between claimed and actual capacity.  The more I look around the more I am concerned I have a bad battery. Thanks, Paul, for the dialogue.

09-14-2022 Post does not mapped to Knowledge Tree rickmcinnis Posts 60 Joined on 10-18-2010 Post #: 1860 Post ID: 26885 Reply to: 26884 The main difference between AGM vs LiFePo Is how long it will maintain voltage and I was a FOOL to think I was saving money by using AGM. The fellow who gave me the idea used LiFePo but did not make it clear to this dunderhead that using the cheaper AGM would give one vastly reduced playing time.  I assumed the only disadvantage was the size and weight. Having a Scots surname gets me in trouble quite often with the cheap gene do ingrained in the psyche. Now to hope there is some kind of second hand market for one month old 137 pounds batteries.

09-14-2022 Post does not mapped to Knowledge Tree Paul S San Diego, California, USA Posts 2,658 Joined on 10-12-2006 Post #: 1861 Post ID: 26886 Reply to: 26885 Likewise With Chargers Batteries are either designed for, or by default are better suited to, specific tasks/routines. Likewise, a given "smart" charger more or less suits a given battery. Caveat Emptor. Paul S

09-14-2022 Post does not mapped to Knowledge Tree Paul S San Diego, California, USA Posts 2,658 Joined on 10-12-2006 Post #: 1862 Post ID: 26887 Reply to: 26886 Not to Advertise/Endorse Wouldn't you know, theses days people actually market batteries for audio use. https://www.ebay.com/itm/311553605415?epid=2255437073&hash=item488a0abf27:g:U2UAAOSwtbFgB1uK&amdata=enc%3AAQAHAAAA8Op60QGTOo3Y6cjW7KxmXC6ojQDWReASpcB6va12Dw39j9MLTgJ0c%2Bw%2BvGkdB4WGr4TxO4Gr3K%2BmD1v%2BGH1AyNFmXrD01SrWske9Jz2x4%2B4qF%2FhNERY1ZB9Fd3StRB0xi6g%2BoDWE7rHM2xGvvHGn1Qa20yPZZaotqRpeV%2Bplsntij4k5%2FH6p55D1QIbeT%2FRa9E254k%2BwKnq0r8A6kyGldBhd5FFXYQSgX4AargpRWUQ%2FFDaLs0jsPKejuQpHerXt7RX55Y62brcYQFlvyQ6XUF3LfLQUJ8Wv%2B3MFZnz7bhBQuY5MgLCSU%2Fi7mhTu%2B1vNpw%3D%3D%7Ctkp%3ABFBMgqT30-dg NOT to say this is for you, or worth a look. Just saying... I have already shared my audio battery experience in my digital audio/DAC thread, FWIW. Paul S

09-14-2022 Post does not mapped to Knowledge Tree rickmcinnis Posts 60 Joined on 10-18-2010 Post #: 1863 Post ID: 26888 Reply to: 26886 Interesting You had mentioned the dry cells before but I was unaware of them. I went with the LiFePo the fellow recommended.  I had ordered it before you posted this. The key is depth of discharge and I am not sure if they are specifying this.  All of their specifications seem to be in their own lingo. Says it is ostensibly a traditional battery which leads me to think I would be in the same position i am already. From what I can surmise a LiFePo will continue to play twice as long as the traditional battery since it can maintain over 12 volts almost to the point of being completely drained and being completely drained does not harm it. Obviously the PUREPOWER and STROMTANK use two smaller LiFePo and run one while the other charges and then switches when that battery is down to its minimum.  This is very clever but with the charger always in operation I would think this must add noise and that switch for the two batteries has to carry a sonic penalty since every switch does in my experience. The LiFePos will arrive next week.  I look forward to getting tired of listening. I did listen with the charger connected and there is extra noise but one could live with it temporarily.  I figure it is better to retain the use of the charger with the batteries fully charged so the batteries behave as big capacitors instead of the charger becoming half of the power supply. I am wondering if there is any benefit to powering SMPS with inverter AC?  I had my music computer connected and then thought I would reconnect it to the line to save on power usage and I think I may have heard a slight difference.  As usual in audio the differences went in both directions for different aspects. This is not a typical ATX supply but a massive MEANWELL 20 volts smps powering DC-DC converters from HDPLEX whose me - much better than even the best ATX - driving a MUTEC MC3+USB (USB to AES EBU) which is also now plugged into the LINE since it also contains an SMPS.  Just curious if such mundane things had ever crossed your mind.  If you use a computer for music files and preferably using WTF as your player - the ultimate minimalist player - the MUTEC will amaze you what is possible with computer audio.  Sorry to have got so completely off of the subject.

09-15-2022 Post does not mapped to Knowledge Tree Paul S San Diego, California, USA Posts 2,658 Joined on 10-12-2006 Post #: 1864 Post ID: 26889 Reply to: 26888 Voltage vs. Current Rick, sure, working volltage is important. What does your inverter require in the way of current in order to produce it's rated voltage at its rated current? I can remember times when I measured "correct" voltage when the battery was functionally useless. I can't think of a battery that is really OK with being drained down past a certain point. Rather, a battery can do only so many extreme cycles in its lifetime, and best to keep it within "working limits". Hence, the "dedicated" smart chargers. Actually, whatever they are made of, the big mobile audio batteries drive powerful DJ/PA type sound systems for hours on end. I don't know anything about quieter/better power sources for computer based sound systems. A telecommunications engineer, John Rankin, who posteed here a few times, sent me a SMPS to use on the heaters of my phonostage tubes; but at the time I recieved the SMPS I was just finishing up a mod to swing the second stage negative, and I did not know if or how to adapt it. John insisted on the benefits of SMPS for keeping noise in LNAs and phono stages to the absolute minimum, and he should know, as that was his full-time job. However, I think they also use brick wall filters that might not "work" for "our kind" of audio. Also, everyone in "professional" sound area uses all balanced systems, with everything grounded, and they all just shake their heads at unbalanced audio systems. Best regards, Paul S

09-15-2022 Post does not mapped to Knowledge Tree rickmcinnis Posts 60 Joined on 10-18-2010 Post #: 1865 Post ID: 26890 Reply to: 26889 LiFePo is very different And I wish I had looked more carefully before taking the cheap way out - which turns out to have become the more expensive way since I have no idea if anyone will buy a month old used battery. From the graphs the traditional lead acid batteries all perform similarly - you get an initial period of full voltage that lasts depending on the load - but then declines in a linear way to the point where you should not go beyond for the likelihood of damaging the battery. I go to 11.5 volts before turning things off.  I got a solid two hours last night after removing the SMPS powered components from the battery supply.  If the LiFePos allow four hours that is longer than i usually ever sit down to listen. The LiFePo's curve looks like a sixth order Linkwitz Riley low pass curve - stays flat (in this case substantially flat) until you reach the "crossover point" and the fall is precipitous.  From what I read it does not ruin the LiFePo battery to be depleted fully.  Of course, the re-charging cycle is probably greatly increased.  There is also advice that taking them down too far will harm the life of the battery.  So not a good idea. I have copied an illustration.   Now I will find out what this means in reality when i install the LiFePos next week. I have to repeat that once one hears what this does, not having the vagaries of the AC line, one would most likely not be able to return even with all of the inconvenience.  AC noise is much like digital noise - it infects the whole "note" - not a noise that resides alongside the note but something that intermingles with it.  One of those things you thought was just how it is until you find you no longer must live with it. As Harry Pearson described the differences between digital noise and LP noise - the LP noise is distinct from the music signal and the brain can learn to disregard it.  The digital noise is impossible for the brain to disentangle.  When he wrote this I had lost my "faith" in Harry Pearson but that struck me as a insight he deserved to be lauded for.  Almost as great as when, in the early years of the magazine, he went on and on about how the Carnegie Hall renovation had bestowed a glassy sound on the Hall only for it to be discovered a decade or so later there had been tons of broken glass placed underneath the stage for some unknown reason.  Though I started out as an 18 years old reading the first issue of the magazine with mindless enthusiasm I had with time become far more cynical about Mr. Pearson's bulls.  But that allowed me to think the really had a fine pair of highly tuned ears even though he played fast and lose with other people's stuff.  Those long term equipment loans were a bit on the suspect side.  (don't know why the font changed. There I go again ...

09-15-2022 Post does not mapped to Knowledge Tree Paul S San Diego, California, USA Posts 2,658 Joined on 10-12-2006 Post #: 1866 Post ID: 26891 Reply to: 26890 Again, what does your inverter require from the battery (in terms of both voltage and current) to put out it's own rated AC voltage and current? It seems like one would want to know this and take it into account before purchasing a battery for the inverter, or vice-versa. I think Tesla uses the LiFePo in their Model 3? But no inverter? They use a diffent battery (with greater capacity) for theiir $$$$$$ models. Paul S

09-15-2022 Post does not mapped to Knowledge Tree rickmcinnis Posts 60 Joined on 10-18-2010 Post #: 1867 Post ID: 26892 Reply to: 26891 Sorry The inverter has a meter that says 0 watts when nothing is connected to it - other than the batteries. As soon as something is "plugged in" it says 40 watts. GIADEL says the unit uses 1.2 amps/14 watts at idle.  I guess it does not really turn on until something is requiring power? I had assumed the mobile hazardous waste dumps all used DC motors but took a look and see this is not correct.  I am surprised that an inverter to allow an AC motor would be more efficient than simply using the native DC.  The whole electric car circus is nonsense to me.  Would be fine with it if there was an abundance of nuclear power plants generating electricity.  Instead we have one of the more grandiose examples of cognitive dissonance ever seen.  Closing down efficient generators of electricity while making the internal combustion engine anathema.  Substituting abundant petroleum for rare metals mined by children.  If it wasn't so bizarre it would be peculiar as hell.

09-15-2022 Post does not mapped to Knowledge Tree Paul S San Diego, California, USA Posts 2,658 Joined on 10-12-2006 Post #: 1868 Post ID: 26893 Reply to: 26892 Pass Through Numbers Well, that does not tell what sort of power your inverter wants/draws when you hook it up to your hi-fi, though it seeems like that is what you'd want to know in order to calculate how long you can listen with a given battery. Paul S

09-15-2022 Post does not mapped to Knowledge Tree rickmcinnis Posts 60 Joined on 10-18-2010 Post #: 1869 Post ID: 26894 Reply to: 26893 The meter shows 600 watts being drawn Which is what i thought I had posted a few times before. I assume 14 watts of that is the inverter. Before I disconnected the computer and USB box it was 640 watts. I hope I am not completely misunderstanding what you are asking for but it is entirely possible!

09-15-2022 Post does not mapped to Knowledge Tree Paul S San Diego, California, USA Posts 2,658 Joined on 10-12-2006 Post #: 1870 Post ID: 26895 Reply to: 26894 Ohm's Law Rick, a 12V battery must put out 50 Amps to make 600 Watts, given 100% efficiency (no system losses). So, the question is, how long can the battery do that, since that's what you're doing with it. It's of no use to have a weak battery that still puts out 12V, because the only way to get 600 Watts from 12V is at 50 Amps. Not to beat it to death, but this means the listening time from your battery is based on how long it can crank 12V at 50 Amps, not how long it can put out 12V. Obviously, if you need more wattage, you need more amperage, too, since the battery is "fixed" at 12V. Paul S

09-16-2022 Post does not mapped to Knowledge Tree rickmcinnis Posts 60 Joined on 10-18-2010 Post #: 1871 Post ID: 26896 Reply to: 26895 No argument The irony is a battery cannot STAY at any voltage for long and as the voltage lowers the current requirement becomes harder to fulfill. The LiFePo will stay above 12 volts for far longer than the AGM if the graphs are to be believed.  One must assume that the amperage will remain as constant as the voltage and in proportion. At the start of a listening session the meter shows 12.4 volts - the load toggles between 580 and 600 watts.   Last night I went down to 11.4 volts before turning off the amplifiers.  About two hours and twenty minutes.  I am letting the voltage sink lower and it does not seem to harm anything. The LiFePo batteries will be here Monday and it will be interesting to see what happens; hope my expectations are fulfilled. I thought through the process as you have and that is why I though the AGM batteries would work.  Only thing i can figure is the fact that the load is constant - no lessening or varying of the load - could this affect the battery's ability to continue to deliver 50 amps for as long as the ratings would suggest?  Of course, both battery types will be affected but it seems the ability of the LiFePo to stay in the 12 volts range longer than the AGM is the key.

09-16-2022 Post does not mapped to Knowledge Tree Paul S San Diego, California, USA Posts 2,658 Joined on 10-12-2006 Post #: 1872 Post ID: 26897 Reply to: 26896 The World of Batteries It's hard to buy batteries based on mfg. info, because they basically just say stuff, and also, as you pointed out, there are many "variables". AGM would work for you, if you got "the right one". Good luck with your LiFePo batteries. I think current/capacity is as important as voltage in your case, and I think when and how you re-charge it will be an important part of how well it works for you, also how long it works for you. Best regards, Paul S

09-16-2022 Post does not mapped to Knowledge Tree rickmcinnis Posts 60 Joined on 10-18-2010 Post #: 1873 Post ID: 26898 Reply to: 26897 I think four of them would work well But i hate the thought of six hundred pounds in such a concentrated spot on a suspended floor. I have this thought: what if the AGMs had a more mellifluous sound than the LiFePo?  And then I figure I need to fix another cocktail. Based upon the reports of the fellow who told me about this I am confident i will get twice as many usable hours per charge with the LiFePos and I promise to tell you if my expectations are not met. Thanks, Paul

09-16-2022 Post does not mapped to Knowledge Tree Paul S San Diego, California, USA Posts 2,658 Joined on 10-12-2006 Post #: 1874 Post ID: 26899 Reply to: 26898 "AGM" I have not shopped to find the smallest thing and the lowest price for it for your use. I can say that some AGMs are dry cell, and some are widely used for mobile sound systems that draw considerably more than 600 W, from a single battery that a strong person could lift. Might find one for under $600. Due diligence is part of the price we are always paying in hi-fi! I've never used my battery for more than 5 hours, and it was still plenty strong whan I shut it down. A friend of mine had twin Tesla batteries that would drive his whole system for quite a while, including 2X 1,200W amps.  Being Scotch, as you say, you would not cotton to the price! Paul S

09-16-2022 Post does not mapped to Knowledge Tree rickmcinnis Posts 60 Joined on 10-18-2010 Post #: 1875 Post ID: 26900 Reply to: 26899 As the old story goes: Scotch is a drink And one I do not enjoy at all!  Rye whiskey is the only proper drink for a citizen of the US! I continue to wonder if the fact that my amplifiers are class a with constant load instead of one that varies has something to do with it.  I wonder if a class ab setup would have behaved differently? I paid four hundred dollars for each of the 200ah AGM batteries.  The LiFePo are just above seven hundred. I hope I can find someone willing to pay half of what I paid for the AGMs.  I DREAD having to move them again. Come Monday there will be an answer ...