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Exact Power EP-15A Operational Question

I am new to the EP line of regulators, so am not sure if what I am observing is or is not "normal" for these units.

With no or very small load, the units (I have two, an older vintage one with a sculpted faceplate and a newest one with a flatter one) drift up a bit to 121 or 122 volts. My house voltage tends to run on the high side. Once loaded both units go to 120 volts. During the times of highest input voltage (123-124 volts), the older unit may go up to 121 volts under load, which is still within their specs. The older unit is typically loaded to ~4 amps rms with two large tube amps. Under this load it runs a bit warm but certainly not hot.

This sounds very benign, but I would like to find out if other EP owners have seen the same beh
dimitry
dimitry OP
83 posts
 
Thanks, I am going to hook an amp per side to see if I like that configuration better. Perhaps the best solution is to have three units - one each for the amps/subs per side and a third for front end components. If I see a new silver one coming up on Agon, I would be tempted!
zaikesman
3,017 posts
 
Hi Dimitry, though I've never used my EP with a sub (because I don't own a sub), having a pretty good idea of the strengths and relative weaknesses of the EP in a high-powered application, if I were you I'd definitely want to experiment with plugging the sub or subs straight into the wall to lessen the demand on the EP, possibly benefitting the other components attached as well as the sub(s).

(Even putting the other components aside -- and admitting my lack of experience in this particular area -- I have to wonder if the EP can really benefit a sub at all. A subwoofer, after all, functions as a steep low-pass filter by definition, with a a turnover frequency that's likely to fall below even the first harmonic of the AC powerline.)

In my system, I've kind of arrived at this rough rule of thumb: If the power transformer in an attached component is physically bigger than the one in the EP, never mind the ostensible wattage ratings, don't take anything for granted -- experiment! As I posted on another EP thread recently, having tried plugging my high-powered monoblocks into my EP and into the wall (via an Equi=Tech 2Q), I find myself wishing there was a way to feed the amps' input and driver stages from the EP, and the output stages from the wall (but since these amps, like most, have but a single main power supply shared by all three stages, this would of course be impossible without a great deal of custom modification).
dimitry OP
83 posts
 
In my case, the subs are actually not big power hogs - these are class D amps type units and used "passively" to fill in the very low frequencies below what the Quads can do - at moderate listening levels - I think they take something like 60W per side or less most of the time. The amps though are Canary CA-339s, so they are spec'd at 360W rms by the manufacturer and register 2 amps steady on the EP and the previous conditioner I used.

The more I think about it the more three units make sense! There is at least some information about EPs not being particularly long lived, so I am reluctant to invest more money into this non-supported technology, but I kind of like the sound and the look of the units.
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