|
Post by AudioHTIT on Nov 10, 2015 10:14:14 GMT -5
^^^ Nice unit bootman, I like Furman products too and use one on my mixer and guitar system (but not this class). I'd probably stick with a small sub panel and a mixed set of outlets, but something like this could make cabling power very clean and easy (electrically, and physically).
|
|
|
Post by westom on Nov 10, 2015 17:28:05 GMT -5
Just explaining why, in general, working at higher voltages has advantages when it comes to power supplies. It has no advantage to a power supply. It has an advantage to wires in the walls. If it had a power supply advantage, then numbers were posted. A 240 volt supply needs half the amperage. Instead of reducing incoming voltage by less than 1 volt, now household wires have reduced voltage reduction by less than half a volt. IOW the efficiency savings might total to a penny a month. So yes, there are savings - in the wires and not in the power supply. And that saving is how much? Massive if making claims subjectively. 'Virtually' zero once we include what honest posts must always include - the numbers.
|
|
|
Post by audiosyndrome on Nov 10, 2015 20:46:33 GMT -5
Just explaining why, in general, working at higher voltages has advantages when it comes to power supplies. It has no advantage to a power supply. It has an advantage to wires in the walls. If it had a power supply advantage, then numbers were posted. A 240 volt supply needs half the amperage. Instead of reducing incoming voltage by less than 1 volt, now household wires have reduced voltage reduction by less than half a volt. IOW the efficiency savings might total to a penny a month. So yes, there are savings - in the wires and not in the power supply. And that saving is how much? Massive if making claims subjectively. 'Virtually' zero once we include what honest posts must always include - the numbers. ? post makes no sense. Russ
|
|
|
Post by richardrc on Nov 12, 2015 21:39:09 GMT -5
Russ, I think westom is trying to say that the I2R losses for the consumer are minimal.
Richard
|
|
|
Post by Talley on Jan 12, 2016 8:35:13 GMT -5
I agree with both of you to some degree. There are MINOR efficiency gains that may be achieved by using a higher input voltage, but pertaining to the OP: Should the sound be any different from a given piece of equipment? NO! Will there be a noticeable reduction in power bill? NO! Conclusion: It's not worth wiring your equipment for 240V!!!! I'm a licensed Master Electrician. I'll explain two reasons why it can improve your audio. 1. voltage drop is reduced by half. For some this could be significant if your panel is farther than 75' away. A high power amp under a peak load even for just a moment could have 7-8 volts of drop on a 120v line but placing this on a 240v circuit could drop this drop by only a few volts. Lets just say a 120v circuit with 10 amps at 75 feet on a 12g wire = about 2.4% drop or you would yield 117 volts. Moving to 240v you only yield 1.2% drop or 237v so proportionally you have less voltage drop. audio equipment work best by more stable AC input. 2. Balanced vs Unbalanced. If your 240V is derived from a single leg of 13kv then your dealing with 7200v transformed down to a 240/120v residential feeder and your service is balanced and the two phases will be 180 degrees apart. This removes alot of a/c line noise going to your AV equipment since the two legs would cancel out DC voltage that gets fedback into the lines by appliances and switching power supplies. If your 120/240v service is derived using two transformers from a 3 phase 13kv system then you end up with an unbalanced phasing since the two legs are 120 degrees apart they will not cancel out common mode noise.... Research audio and balanced isolation transformer. When you have 120v there are many who would move to a balanced 120v 1:1 isolation transformer which turns the 120v hot and 0v grounded neutral into a 60v/60v balanced system much like the 240v service is two legs of 120. This is because the two 60v legs are now 180 degrees apart and remove common mode noise. Just facts... don't hate.
|
|
|
Post by sidvicious on Jan 12, 2016 20:02:36 GMT -5
My dealer hooked up a system for a guy who was overseas and has Audio Research equipment and has now moved his business back to the US. My Dealer told me that he had to rewire one room of the customers house for 240 volt because Audio Research won't switch power supplies and supply equipment for the 120 volt changes. My dealer stated they hooked everything up and he said exactly what you just said, the system was a lot better at 240volts, everything was more engaging.
|
|
|
Post by leonski on Mar 5, 2016 3:35:37 GMT -5
I didn't mean that I would save money, but servers do use less power at 240 and can save money for a large data center. The only way it can save money is on long transmission length at high current levels. This is why AC is transmitted at very high voltage levels and then stepped down at the destination. I do imagine that a larger server-farm with high current needs could have high drops even inside the building where housed, but this serves no practical purpose when dealing with a 15 or 20A line. The OTHER way it can save money going to 220 is if the Power Factor is closer to true resistive. You get billed for Watts and Use VA. VA is the result of voltage and current No longer being 'in phase'. The very definition of a reactive load. Some large companies get a bill adjustment for low power factor. If it is bad enough, these same companies Might invest in Power Factor Correction.
|
|
|
Post by westom on Mar 8, 2016 11:42:03 GMT -5
The OTHER way it can save money going to 220 is if the Power Factor is closer to true resistive. Bad power factor means 'they' must provide more power (real and reactive). But you are still billed same and only for consumed real power. Even a trivial and reduced voltage drop in wires is near zero 'saved' money. Power factor does not change with less voltage drop (due to resistance) in wires. Power factor is determined by the load. Quality of sound must not change even when AC voltage varies from under 100 to above 125 volts. A power supply must provide same rock stable DC voltages irregardless of massive AC voltage variation. Audio amps only see DC voltage. If that voltage is rock stable, then audio does not change. AC voltage must vary widely and DC voltages still must not change; - if an amp's power supply is properly designed. My car also drives better after I have paste waxed it. Observation proves it - when conclusions are not tempered by numbers. Had audiosyndrome tempered his conclusions with numbers, then the post makes sense. He would have understood near zero saving - ie a penny a month.
|
|
|
Post by 405x5 on Mar 8, 2016 11:50:06 GMT -5
So I've been experimenting with high end equipment and learning a lot... sigh. We are talking $3000-$4000 amp/DACs. But my system have now settled with 2 Focal SM9 and an Emotiva XDA-2. Sounded pretty good on 120V, better on balanced 120V. But then I switched to 240V, and.... WOW. This system have never sounded this good, extremely emotionally engaging., I find my self playing my entire playlist for hours on end. Previous setup I had may have sounded better, but was nowhere near this engaging... Weird... Oh well, I know I am responding to the opening post. Never the less, I wanted to thank you, for a smile and a good laugh this morning (especially the singing part! )
|
|
|
Post by leonski on Mar 8, 2016 12:29:45 GMT -5
The OTHER way it can save money going to 220 is if the Power Factor is closer to true resistive. Bad power factor means 'they' must provide more power (real and reactive). But you are still billed same and only for consumed real power. Even a trivial and reduced voltage drop in wires is near zero 'saved' money. Power factor does not change with less voltage drop (due to resistance) in wires. Power factor is determined by the load. Quality of sound must not change even when AC voltage varies from under 100 to above 125 volts. A power supply must provide same rock stable DC voltages irregardless of massive AC voltage variation. Audio amps only see DC voltage. If that voltage is rock stable, then audio does not change. AC voltage must vary widely and DC voltages still must not change; - if an amp's power supply is properly designed. My car also drives better after I have paste waxed it. Observation proves it - when conclusions are not tempered by numbers. Had audiosyndrome tempered his conclusions with numbers, then the post makes sense. He would have understood near zero saving - ie a penny a month. My understanding is you are BILLED for KwH and use VA. so if you have a wacky PF, you use more power but are billed for KwH. Major companies with a PF problem can get a bill SurCharge. I don't think that is (yet) done for homeowners. I just gave it a try. I have NO idea if the PF of the amp changes as a function of voltage. IF it changes for the 'better'? Possible MINUTE savings. As for 'rock solid'? For a regulated supply, maybe, but few stereos use such. Most PS will 'sag' if loud enough / long enough. At least down to the RMS rating. As opposed to any dynamic rating.
|
|
|
Post by etc6849 on Mar 9, 2016 12:55:43 GMT -5
Guys, the reason is i^2*r losses (e.g.heat produced) will always be lower for lower magnitudes of current. Power = voltage * current. Power consumed will be the same, voltage goes up, so current must decrease.
EDIT: I NOW SEE PAGE TWO LOL. DANG SMARTPHONE.
Any ways my XPR-1's get hot, so I'd expect them to give off half the heat on 240v since heatrate will be directly prop to kWh (real power that is paid for on my electric bill but is lost). Maybe this is a 10-20 watt savings?
Negligible is the fact that resistance of a conductor changes as it's temperature changes.
|
|
|
Post by mgbpuff on Mar 9, 2016 14:01:44 GMT -5
Guys, the reason is i^2*r losses (e.g.heat produced) will always be lower for lower magnitudes of current. Power = voltage * current. Power consumed will be the same, voltage goes up, so current must decrease. EDIT: I NOW SEE PAGE TWO LOL. DANG SMARTPHONE. Any ways my XPR-1's get hot, so I'd expect them to give off half the heat on 240v since heatrate will be directly prop to kWh (real power that is paid for on my electric bill but is lost). Maybe this is a 10-20 watt savings? Negligible is the fact that resistance of a conductor changes as it's temperature changes. Your XPR-1s will get just as hot on 240v as on 120v. The heat is due to DC bias currents which occur after the power supply conversion to DC. Perhaps a very small heat loss reduction would be present in the primary windings of the power supply transformer due to lower primary I2R loss, but very little, because magnetically the same amp-turns exist inside the power supply transformer whether the primary voltage is 120 or 240.
|
|
|
Post by leonski on Mar 20, 2016 22:13:50 GMT -5
While E=IR, for sure, what you are worried about is the power liberated treating the wire as a resistor. IR DROP. BTW, DOUBLE the voltage at HALF the current results in the SAME power. IF resistance is the same. www.ohmslawcalculator.com/ohms-law-wheelI'm linking this handy-dandy calculator. Look up power, which is what we are really concerned with. Your electric bill IS for KwH. No question. And assumes your house 'appears' to the power company as a resistor. Pure heat loss of current and voltage IN PHASE with one another. This is seldom the case. The reality is that most loads appear as some combination of resistive and reactive elements. Impedance. In the case of a REALLY awful load of high magnitude, the power company may actually DING you a surcharge for poor power factor. This won't happen at your home, but the local factory with a couple hundred HP of induction motor or thousands of watts of Fluorescent lighting MAY get such a surcharge. While I doubt it is the case, I postulated that the amp in question MAY have a slightly different Power Factor when run on 110 or 220. If the amp looks more like a resistor TO the power company at the higher voltage, that might be a slight advantage FOR the higher voltage.
|
|
|
Post by Kent on Mar 20, 2016 22:36:38 GMT -5
Each of my XPR-1's have dedicated 20 amp 220 volt lines using 10/3 wire. I've never heard them any other way so I can't comment on whether it's better or not. However, they do sound fantastic fed this way.
|
|
|
Post by garbulky on Mar 21, 2016 9:07:33 GMT -5
You guys going on about balanced power has really got me thinking. So 240 cures the 60 hz buzzes?
|
|
|
Post by Priapulus on Mar 21, 2016 9:12:22 GMT -5
My power utility company recently replaced all the lines and transformers in my part of the town. I notice the voltage is significantly higher now. I wonder if this is just a sneaky way to increase revenue? Higher voltage = higher kwh = $$$?
Sincerely /b
|
|
|
Post by monkumonku on Mar 21, 2016 9:24:58 GMT -5
You guys going on about balanced power has really got me thinking. So 240 cures the 60 hz buzzes? Maybe but then what if you then get 120 hz buzzes?
|
|
|
Post by Cogito on Mar 21, 2016 9:33:11 GMT -5
My power utility company recently replaced all the lines and transformers in my part of the town. I notice the voltage is significantly higher now. I wonder if this is just a sneaky way to increase revenue? Higher voltage = higher kwh = $$$? Sincerely /b Higher voltage = Lower amperage. Wattage stays the same.
|
|
KeithL
Administrator
Posts: 9,966
Member is Online
|
Post by KeithL on Mar 21, 2016 10:12:57 GMT -5
Errrrr.....probably not. It really depends on what the cause is to begin with. A balanced power feed, which a 240 VAC feed may be, may reduce certain types of noise. However, most of what we think of as hum is the actual 60 Hz magnetic field from the power lines finding its way into sensitive circuitry - and that isn't going to change. Therefore, depending on the source of your buzz, it's possible that switching to 220 VAC might reduce it - but, then, simply having your house rewired with new grounds also might fix it - or using a good line filter might fix it. (It's not going to be some sort of cure-all. In fact, it's probably pretty far down the list in terms of being likely to help. But it could.) I will also tell you that the SMPS in our new XPA Gen3 amps will in fact deliver slightly more power under some conditions when run from 230 VAC. (The ratings are all taken at 120 VAC, and it won't affect the way they sound; we're talking about a little extra power under what we consider to be "lab test" conditions.) You guys going on about balanced power has really got me thinking. So 240 cures the 60 hz buzzes?
|
|
|
Post by Priapulus on Mar 21, 2016 10:15:09 GMT -5
My power utility company recently replaced all the lines and transformers in my part of the town. I notice the voltage is significantly higher now. I wonder if this is just a sneaky way to increase revenue? Higher voltage = higher kwh = $$$? Sincerely /b Higher voltage = Lower amperage. Wattage stays the same. i=e/r Higher voltage / same load resistance = higher amperage, wattage goes up... /b
|
|