exactpower ep 15A

Seeing this thread pop up again, I must provide a link to another thread I posted to recently for my latest thoughts on using the EP-15A with high-powered monoblocks.

Upshot: I now plug my Equi=Tech 2Q that feeds my monoblocks directly into the wall instead of into the Exact Power, purely for sonic reasons (as stated above, I never had any problems that went to reliability). It's a tradeoff -- I do miss some of what the EP provided with the amps, but overall I've decided that in my current setup it's better if it doesn't feed the amps, only the sources (still via the PW Ultra with its b.p.t.'s)

I think I would probably love it if there was a way to feed the monoblocks' input/driver circuitry from the EP and their output circuitry from the wall (both via an appropriate b.p.t. for balanced AC), but unfortunately that's just wishing.

I am also an EP-15A owner, and spoke with MAP a few months ago about my sentiments regarding the excellence of that product and my disappointment that the new company has abandoned it. However, although I can't recall a name, I'm sure I was only speaking with someone in customer service, not a company officer.

I do want to mention, in light of above comments, that it's perfectly fine to hang a balanced power transformer off the output of an EP-15A, and in fact that's what the old Exact Power company intended for their complementary SP-15A unit, which is generally similar in principle and execution to units from Equi=Tech and BPT.

The combination of voltage/waveform correction from the EP and further noise-reduction/balanced-AC from a b.p.t. connected in series is not something I'd want to be without. I believe balanced-AC does more than just reduce powerline noise, I think it allows connected components to actually function better in and of themselves, often significantly so.

I myself take the wall power for my entire high-powered, bi-amped system and route it first to the EP-15A, then to an Equi=Tech 2Q for the power amps only, and also to an API Power Wedge Ultra 116 for the preamp and all the sources. (The PW uses six invidual smaller b.p.t.'s with six individual outlets to provide balanced AC for low-power sources while isolating all sources from each other on the powerline. However I do not recommend using the PW's four power amp outlets, which aren't balanced, for that purpose, or any other if you can avoid it, other than possibly feeding some battery trickle-chargers which may not accept balanced AC.)

BTW, not to jump on any PS Audio bashing bandwagon, because I generally like and admire the company and use one of their products, but it's worth noting (and has gone nearly unremarked-upon) that while the original Power Plant models did provide balanced AC, the current PP Premier that replaced them does not. The company has been, perhaps unsurprisingly, totally silent about this change in philosophy, as have all the reviews I've seen of the P3 whether out of acquiesence or ignorance. But if you followed the debate that took place in the Letters pages of Stereophile several years ago between Paul McGowan of PSA and Equi=Tech's Martin Glasband, McGowan stipulated that in his opinion at the time, balanced-AC was the THE single most important factor in terms of sonic improvement among the original PP's functions.

Also, for anybody considering the Equi=Tech 2Q (at least as it applies to high-powered power amps), I have found that in order to obtain the most dynamic, widest-bandwidth sound, I recommend using only the unswitched GFCI outlet duplex for that purpose, and if you use none of the other switched outlets for anything else, then in addition turn off those unused outlets from the front-panel rocker switch.

Hi Nsgarch, thanks for the update (actually I haven't followed any other Exact Power threads lately, so sorry for making you reiterate stuff you've posted before).

Let me state for the record that, while you may be qualified to commment on an electrical engineer's capabilities or the vagaries of the powerline, I am not. But I will share my own experience using the EP-15A in relation to the issues you raise.

My EP-15A is I believe the first version sold, at least in terms of cosmetics (after it replaced the model that preceded it -- the EP-2000 or something like that?), but I don't recall at this point what substantive differences (if any) may have pertained between it and a later version. It's plugged into the common 15A house wiring and breaker-board via a 3-pronged outlet and cord, no upgraded or dedicated circuit or added earth grounding.

I have no idea whether or not my unit has the added thermistor you mention, but as I'm sure you know, it does by design momentarily switch over to straight wall power when the draw exceeds its capacity, as during power amp turn-on (or very occasionally during program peaks at the highest listening levels, to allow unimpeded dynamics). I would have thought that this feature might itself innoculate the unit against damage from excessive current draw. The high-powered amps I've used with the EP include tube monoblocks rated 225wpc and solid-state stereo and monoblock models rated from 400wpc to 500wpc, the latter types in bi-amp combination.

Other than during vacations, my EP is normally left continually on (except for when heavy weather threatens and I unplug the entire system), my amps usually not. As per Equi=Tech's recommendation, the 2Q is normally also left permanently on whenever the EP is powered-up, but in any case it doesn't seem to draw an inrush current at turn-on equal to what any of my power amps do, as it has only rarely (maybe 5% of the times I've turned it on) caused the EP to default to wall power, whereas the power amps virtually always do. (The Power Wedge Ultra doesn't have an On/Off switch, which sonically speaking I think is even better -- but there isn't a draw issue either there or with the source gear connected to it.)

Of the amps I mentioned, the tube monoblocks seemed to cause the biggest powerline sag at turn-on, and if not staggered would routinely trip the house circuit-breaker. Yet none of this has ever caused any problem for or with my EP, which has in fact been totally problem-free in the several years I've had it (knock on wood) through thousands of amplifer turn-on cycles, as well as many powerline interruptions sufficient to cause it to reset (easy to see in retrospect because I normally keep the digital display switched off and it defaults to On mode).

So for me at least, so far so good (my criteria being entirely sonic and not alleged lightning-strike protection) -- and I wouldn't bother with the extra expense did not the b.p.t.'s I'm using in conjunction make a worthwhile improvement over using the EP-15A alone (and vice versa).