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I'm trying to make sure I'm running enough amps into my basement sub-panel, but really have no idea how many amps 5-channel amplifiers can pull. So, if anyone can tell me how much juice is required for any of these amps, I would appreciate it...


-Acurus 125x5

-Acurus 200x5

-ATI 1505

-ATI 2505

-Parasound 2205


Thanks.
 

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Honestly, your best bet is to check for a spec that says "maximum power consumption", which is probably spec'd in watts.


Then divide by 120 (if you're in the US) to determine amps used.


Lacking that, to get an accurate value, your only recourse is to check with the manufacturer.


We could give estimates, but that's all they'd be.


Regards,
 

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Shag-


Unless your speakers are very in-efficient and in a cavernous room, it is very unlikely that any of the amplifiers listed above will pop a 20A breaker. If you also have a large, high power subwoofer in the system you may want to allow an additional circuit for it, and in the ideal, then another circuit for all of the front end electronics and video equipment. What can be as or more important is the method and type of circuit wiring. Of interest is to reduce opportunity for voltage sag under heavy load, and ground potential differences. There are some more power hungry and less efficient amplifiers like Krell's FPB series, and other more spectacular designs. Most manufacturers will give you good guidance as to real world power demands, but a good indicator of a power hungry amplifier is heat. The more heat an amplifier is dissipating, the lower percentage of the power which is going to the speaker.


For those asking how they can tell if they have a problem with voltage sag, take your standard, dimmable torchlite and plug it into a receptacle on the same circuit and ideally same location of the components in question. Now dim the light down to be just barely on, where lower settings turn the light off. Now play your favorite action flick or other taxing program material. Watch the light, if it dims with peaks in the soundtrack, the voltage is sagging.
 

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Mark,


As a fellow resident of Com ED land, you know that we are typically starting out a bit on the low side :-(


What do you do when you're starting with what would be considered a voltage sag ;)


Regards,
 

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Quote:
Originally posted by John Kotches
Mark,


As a fellow resident of Com ED land, you know that we are typically starting out a bit on the low side :-(


What do you do when you're starting with what would be considered a voltage sag ;)


Regards,
Good one John, ;)


Actually, around our area I've seen a range of 110V to 118V measured with a voltmeter. If someone is close to a generation plant, they can sometimes see as much as 125V. Interestingly, this isn't THAT big of an issue in our audio systems, as in design they should be considering a 10% variance in actual line voltage. What this does mean is that the lower your line voltage, the higher the current demand on the line to deliver the same power. Lower line voltages will also reduce the peak power capacity of any amplifier with a non-regulated supply.


What is actually of more intrest for audio use is to maintain a constant voltage, not necessarily a specific voltage. When the line voltage changes, non-regulated power supplies will swing right along with changes. This causes a modulation(fluctuation) of the power line which can cause varying distortion from the components as their gain and distortion levels swing up and down with the line.


Traditional regulated power supplies in amplifiers are expensive and in-efficient while generating a lot of waste heat. Krell, Boulder, and a handful of others have advanced this form of regulation to only draw as much power as is actually required by the input signal. Ironically, I've had the opportunity to push many a Krell to pop a breaker. What actually happens is that the heavy current demands of the amplifier at high output levels causes a voltage sag at the wall receptacle, and then the regulation in the power supply reacts and draws more current to maintain the power supply voltages, which causes further sag on the line with a circular effect. If this occurs for any length of time (talking miliseconds) here, it will most certainly pop the breaker as we want to. This is where running larger guage wire and/or short runs from the distribution panel are desireable for hi-fi use.


The latest technology to better battle this problem are some of the newer class-d or similarly high effeciency designs. Many amplifiers are also now using switchmode power supplies which can provide a constant output in light of variations of the line voltage, but to do so they do still draw the required quantity of power, so at lower line voltages, they draw more current.


Fortunately these higher efficiency designs often draw only 1/2 the current of a comparably powerful Class A/AB amplifier. Now if you happen to combine this with some rather efficient loudspeakers, then the demands go down 10-fold or more. ;)
 

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Mark,


I'm very fascinated by the potential of digital amplifiers in their several incarnations (Bel Canto EVO, Tact Audio, Sharp 1-bit and Spectron) and hope I get to play with them.


The high efficiency (> 85%) is a god send in HT environments.


Regards,
 
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