that is fairly common and should not be a problem |
As Philjolet posted, not uncommon at all. I've seen homes with 112 at the outlet and others at 129.
My home is 121.7, so pretty close to what it should be. I would not worry, the real problems come with very low and very high voltage.
Two years ago we had a transformer fail in the alley and we were getting about 68 volts for almost a day, until I figured out what was going on and called TXU Electric.
We lost our clothes dryer, microwave and later the refrigerator due to "brown out." |
The standard is 120V nominal + or -5%. In other words it can vary from 114V to 126V. I would love to have 116 in winter,I have 125V most of the time unless its hot summer with a lot of air conditioning going.Most of your lights and other stuff will last longer.Refrigeration and other equipment might like 120 better.Its within limits,but if you live in an all electric area,the voltage may drop more when its cold and the electric heat puts a heavy load on.I have 115v in the summer,and the a/c runs a lot.I don't think it will bother most audio gear.You could complain,then they may put a recorder on,and correct it.Or they may turn the regulator up to 125V. Then your bill may go up,plus shorter light bulb life and some electronics may run warmer.Its hard to say,but in the summer,if your area gets hot a lot,it may drop lower yet,then I would complain.It would be nice to have 120 all the time.I'm not an electrician,but that's my opinion. |
Mostly I have 118. During peak demand of summer, it'll droop as low as 115.
Lower voltage implies higher amps for same power. |
Magfan - Not necessarily. My amp (Rowland 102) has SMPS and produces the same maximum power for supply voltage 85-265V. |
Kijanki,
Off topic, just curious if you ahve your JRDG 102amp powered up directly from the wall or power conditioner? |
Nasman - I had it powered from the wall but recently I added Furman Elite PF20 conditioner. Rowland is plugged into high current bank of outputs. It removed bass resonances (nodes) while not affecting dynamics and opened midrange a little (Furman supposed to increase available peak current to 55A). I'm not sure if midrange is due to Rowland or Benchmark DAC1 (that drives it directly) that is also supplied thru conditioner. It could be that bass resonanses were masking midrange. The really strange thing is that TV picture got cleaner, brighter and more vivid (stronger colors). Furman supposed to correct for power factor and TV is DLP (projection). Maybe just bulb is brighter now in addition to digital noise reduction (HDMI). |
Hiendmmoe - Amplifier will be louder at 120V (unless is regulated) than at 116V by less than 2%.
(120^2/116^2)^(1/3.5)= 1.0195 |
Kij, Yes there are many SMPS which run at a wide range of voltage. My charger for my Canon camera will run on anything it'll plug into. anywhere. NO DC.
But, in general, is it true that lower voltage makes for higher current draw? If your PS draws 1 amp at anything from 85 to 265 volts, that would make it 85 to 265 watts, if it was a pure resistive load (I'm sure it isn't)
But, for 100 watts, the current would vary from 1.2a to 0.4a for the same 'power' in watts.
I don't know the answer. |
Magfan - No, lower voltage doesn't make for higher current draw (it happens in SMPS) but only limits max peak power. Amp in a sense is a regulated supply that delivers required (at given moment) voltage to the load (speaker). If it runs out of available supply voltage it will start clipping. If you don't use whole available power then line supply voltage change won't affect you.
What amp takes from mains is completely different story and depends on type of amps. For class A amps it will be constant current while for class B it will be just a few percent of max rated power of an amp. The reason for that is that music has very low average value and scale is logarithmic. When sound level is at 1/2 of max loudness amp takes 1/10 of max power.
Linear power supply takes current from the mains in very narrow spikes of high amplitude. It is in a sense SMPS that operates at 120Hz. Width of the spike depends on the current demand but also on output impedance of transformer and ESR of capacitors (Schaffer diagrams). It is called conduction angle. Because of that transformer has to be oversized (RMS power required is much higher than average power taken + high frequency content is heating the core) and power supply wiring and cords have to be oversized to avoid drops.
Linear power supply is therefore pretty noisy outside and using shielded power cables is needed. |
Yes, power factor.
Same thing happens with speakers where people insist on saying bad load=low impedance when really it is hi phase angle AND low impedance at around the same frequency that makes for a bad load. For speakers a Smith Chart tells the whole story. Phase and impedance as 2 lines always confuses me. Smith Chart is easier to read, after a small learning curve.
I will measure the PF of my gear. I suspect no worse than 30"=0.86 pf.
This is within reason and not unexpected. Remember, we may get billed for WATTS, but consume va. That's why transformers are always rated in VA and not in watts. And, as an aside, some factories get billed a 'premium' for low PF load. Your stereo can be the same way.
'A' amps are always on, so at 100% all the time.
Agreed about average draw. If the power factor is reasonable, no need to overdo it too much. 14ga should still be good up to what......1000va? |
Magfan - power factor is on the top of it but I was talking about current that linear power supply takes from mains - it is not sinewave but series of high amplitude spikes.
Power factor in my system is corrected by Power Conditioner - I'm not sure how. |
PF, at least on an industrial scale can be corrected. Capacitor banks for sure will work, and maybe an inductor bank. Depends on if current is ahead or behind voltage. Using iron core inductors with the core being 'movable' will vary inductance. I don't know what technology is used on that scale.
Why do you bother with PF correction? Your amp PS will still have the same electrical characteristics. Only what the power line 'sees' will change, and if you aren't being billed a low PF surcharge, why bother? PF correction is used on big scale factories so they don't get dunned an additional electric bill....a 'weird load' penalty. My company, for example, was getting tagged for 600$ monthly and PF correction would have a payback measured in decades. I haven't looked up your system, but if as I suspect, you have at least a dedicated line to anything short of a couple KW of A/B amp, than you should be ok with a 20 amp service!
Better results, (just an OPIN) could be obtained if speaker designers quit messing around. Some speaker loads are AWFUL and since they are tough to drive, IMPEDANCE gets (mostly) wrongly blamed.
As a Power Supply aside, my now ancient Carver Cube used an early version of what became his 'tracking' powersupply. I think this PS was voltage driven, since I could cause the lights in my house to flicker in time with the music. |
Magfan - My Conditioner corrects it, but I bough it purely for filtering and good non-sacrificial overvoltage protection. I cannot often understand how things like power cables or conditioners improve (or destroy) sound but I trust experience of fellow Audiogonners.
As for dedicated line - I'm running it on standard 15A outlet. It is legal to connect 20A conditioner but main 15A breaker might go first in case of overload. In addition I got good deal on Audiogon plus 20A unit should be beefier than 15A. I was concerned since many people reported conditioners killing dynamics. Not in my case. |
my 'current' (please ignore pun) pc is a Panamax in the 5100 series.....don't 'member which. But it has a 400va iso into which all my low current stuff plugs. This thing really delivers using those outlets.
I've had 2 amps plugged into it for testing. A vintage Carver cube and a Rotel rb1070. I felt both were limited by the conditioner, even into the alledged hi-current outlets. The cube, in particular really opened up when straight into an outlet, even the 'shared' circuit before a dedicated line. The Rotel simply didn't have enough oooomph for my panels at higher levels but also improved straight into the wall.
Now, I have a dedicated drop and use a PSAudio Soloist outlet for my GCC250 and HSU sub.
One day I'll get around to measuring the PF of all this stuff and get back to you. But for now, I just listen. Even the XM coming down the pipe thru the small dish is terrific background music and turned up, not all bad. Certainly as included with the rest it is great and gives me a chance to hear stuff which I'd not otherwise listen to.
IMO, and I've got LOTS of 'em, cabling is one of the last things to 'fix'. Fundamentals count here more than glitz and weird science. Room 1st.
As for PF, again, speakers are the worst offender and many otherwise good amps have been replaced due to the owners insistence on speakers with bizarre load characteristics. There is NO excuse for a 60' phase angle right next to a 3.5ohm dip in a 86db sensitive speaker, all happening at say......200hz. |
"Fundamentals count here more than glitz and weird science"
Magfan - Open minded people get extra benefit of better sound thru placebo effect while sceptics and "scientists" will never get improvement in cabling. |
OUCH!
I've always been pretty skeptical. Claims which are noted but not repeatable are always.....suspect.
I've heard enough people complain about amps thru pcs that when my sound changed for the worse thru such a conditioner, I was convinced of at least that.
I can get a cable to make a difference....easily. Just hook my current hog, fairly low impedance panels up to my 500x2 4ohm amp....using 18ga wire. or stick a small value cap across the outputs. |
Magfan - It is possible that I don't have any loss of dynamics with conditioner because of SMPS that is regulated. If conditioner drops voltage at high current peaks SMPS is responding fast holding regulated voltage on the output. Icepower class D amps were praised in few reviews for holding composure during loud, heavy orchestral pieces. It might be because of this SMPS. Traditional power supply can do the same with a lot of electrolytic capacitors. |
