Exact power.....hookup question


One more question.....if I have an EP-15a and a SP-15a, do you reccomend hooking the SP-15a into the EP-15a or hooking them each up to a seperate ac outlet?

Thanks again!
naperaudio

Showing 3 responses by nsgarch

ABSOLUTELY NOT!
And that's unfortunate because it would be nice to enjoy the benefits Bill-k mentions. However, the EP-15A was built without adequate turn-on protection circuitry, and if you turn it on at the 'wrong' point in the 120VAC power cycle with the SP plugged into it in the on position, then the big toroidal transformer in the SP (along with any switched on equipment plugged into the SP) will put too large a current draw on the EP's internal components and fry them.

In fact, even if you have the SP in the 'off' position and all attached equipment to both the EP and SP in the 'off' position as well, fuses will blow (or worse!) as soon as you attempt to turn on the SP

I know it says (even recommends) that you can/should use them together in the manual, but in reality it's a no-no! 2 years ago when I was in touch with him, the new owner of the Exactpower name and patents talked about a bullet-proof, high capacity EP-20A, which because of the patented feed-forward circuitry would blow all other such equipment off the map. So far that hasn't materialized.
Based on what I have read it is generally better to hook up the source components to the SP-15a and my tube monoblock amps to the EP-15a.
Yes I would agree with that -- it's how I have my system configured. I have both units on the same dedicated circuit, so most powerline noise is at a minimum anyway. And the SP (balanced power transformer) gets rid of anything else through 'common mode rejection'.

I have all my source equipment plugged into the SP, because those devices benefit most from balanced power. The EP (which is at the front of the room between my amp and (powered) electrostatic speakers support those devices. Tube amps in particular, benefit from the VOLTAGE REGULATING capability of the EP because otherwise tube bias will fluctuate with changes in line voltage.

Neil
.
Chessman, even though you didn't mention what kind of amp you have (and your system is not posted ;--( please try plugging your SP directly into the wall, and your amp into the EP. I bet it won't blow the fuse. Amps benefit GREATLY from being run through the EP (especially tube amps) and I'm pretty sure it's the SP PLUS the amp that's blowing the fuse. If the amp STILL blows the fuse in the EP without the SP transformer's huge start-up load, there's probably something wrong with the turn-on circuitry of your amp. The EP has a 1500 to 1800 watt capacity (depending on your house circuit rating) and there are VERY FEW amps that would exceed that -- even on turn-on. I know you say both units are left on all the time. If that's the case, the fuses can still blow from short power drop-outs (as opposed to surges) but not from the equipment itself. For instance when the power drops for just a split second and then comes right back on, the turn-on circuitry of most power amplifiers won't have time to cool down and reset -- so that huge (unprotected) draw can also pop the fuse.

BTW, to get the superior amplifier performance possible with the EP, it's important to use power cords for both the amp and the EP with a minimum conductor size of 10 AWG. The small 12 and smaller 14 AWG cords that manufacturers supply with their equipment just don't have the energy transfer required for best performance.

Please try that arrangement (using minimum 10AWG power cords) and let us know what you think -- I bet you'll be pleasantly surprised!

Neil
.