Krell Power Consumption


Hi,

I'm a bit new to ultra high end. I'm considering a Krell Evolution 402. One thing that jumps out at me is the power consumption in standby. The manual says it draws over 300 watts in stand by and recommends that you leave it on all the time. 300 watts 24/7. Good grief. Is this bogus or just the price you pay for a serious amplifier?

thanks for any advise.
wrf
Dob,
As far as I know, regulation and PF should be unrelated.
PF is a measure of the reactance of a load, be that inductive or capacitive.
A (perfect) resistor has a PF of 1.0 while at a PF of 0, no work is done.

I'd be curious to know how PF and regulation relate.

Thin Ice alert:
Isn't regulation simply how well the PS maintains voltage under load? Aren't their either formula answers or 'rule of thumb' answers to how much capacitance a PS needs given voltage and proposed power output? Doesn't that kick out a %ripple number....lower generally being better?
Tmsorosk:
PF is a measure of the reactance of the load.
your monster will display what? Watts or VA? maybe Amps and Volts?

I doubt it displays PF.

Just an example. My 40 watt fluorescent lamp next to my workstation measures about .34 amps. at 117.5v that is about 40va. But, since the lamp has a PF of about .8, it is only about 32 watts.
My electric company (yours, too) bills for WATTS but you use VA. The electric utility company will bill you a surcharge for Low PF. Some factories even have huge PFC correction circuitry in order to avoid this surcharge.

If you want to just monitor power consumption and get an idea what the PF of various devices is, get the 'Kill-A-Watt' meter.....they are very inexpensive and functional.
"I'd be curious to know how PF and regulation relate. "

Hello Magfan: It is that PF correction, as I wrote above, remove ripples and other "terrible" artifacts which produce odd-order ear-piearcing harmonic distortions. Please see below from Jeff Rowland web site:

"External JRDG PC1 is active Power Factor Correction (PFC) units. These devices preconvert the AC from the mains to a steady 384V DC current fed into the monos through a banck of intermediate charge capacitors and make the "501" much less sensitive to AC noise and fluctuations. They also keep the 501s internal caps optimilly charged avoiding AC induced ripples. PC1s should yield even larger authority to the "501"s and will give them a lot more subtlety and nuance"

mote "avoiding AC induced ripples ".

Effects of ripples and other things on distortions are desribed in Simon Thacher of Spectron paper:
http://www.enjoythemusic.com/magazine/manufacture/0708/index.html

All The Best
I guess we're talking about 2 different things.
Power Factor is simply the phase relationship between voltage and current in an AC signal...be it the power coming in or the audio to your speakers.

The JRDG approach is a complete power supply and IMO, the PF is tossed in as an advert blurb. This does NOT mean the power supply does not work as advertised. Just that PFC doesn't have much to do with it.

The article you linked is good....as far as it goes. In the discussion of REAL speaker loads, NO mention is made of phase angle. At a phase angle of 45 degrees....not uncommon, the delivered power will drop by about 30%. This represents an additional load to the amp. Now, I realize the numbers were used for illustration purposes only, but that is the real effect of phase on deliverable power.
The same is true of the power supply as it plugs into the wall. I'm no expert at this, but if your power supply has a 100va transformer and a PF of say.....0.8, you won't be able to get the full power out of the transformer..it'll saturate.

Does the JRDG amp deliver? You bet. Does PF have much to do with the rest of the claims? I'm a little leery.
FYI, I did go from the FPB Cx amps to the Evo stuff....drumroll........keep the FPB stuff if you have it! Krell is now obsolete. Moment of silence please:O(