Originally Posted by mtbdudex
late to this thread.......this comes up every 2 months or so, I advise people:
Check the back of your equipment or the owners manual (online for planning purposes)
It has this info, max current needs, here my EP2500 uses 9.5A @ 120V
Just fyi, the EP2500/4000 can pull ~2400watts, or ~20amps with test tone type material. It's dependent on the load presented across the speaker terminals on the amp. Whereas encountering voltage clipping into 4ohms, would be draw double the current as hitting clipping into an 8 ohm load. When I say "test tone type" material, what I'm referring to is the larger LF effects that accompany contemporary BD/DVD releases. Some of these are much more similar to test tones, than the spectral characteristics associated with music releases. Some HT LF effects, such as those found in HTTYD (How to Train Your Dragon), are nearly as wide as the spec, 3hz-120hz, very high in level, torturous and long in duration. Hence, a bit more related to test tones
, than the typically less demanding music. Other effects, such as the outstanding gunfire/blasts that occur in the fanstastic Open Range, are very high in level, however they're very brief and clearly deliniated. Very demanding of a system's transient capability, but possess no longer term demands on current delivery.
Back to the Behringer EP2500/4000; it's been measured at
8 ohm stereo=450w
4 ohm stereo=635w
2 ohm stereo=815w
8 ohm mono=1336w
4 ohm mono=2000w
So, being a class H amplifier, with a multi rail voltage supply, efficiency is in the area of 83%. (2000/2400). As I illustrated above, the amperage drawn at clipping from the wall, depends on the load across the amps terminals. Taking this a step further, as one lowers the impedance even more, approaching a short circuit, the amp will pull so much current that the amps on-board breaker, or the branch circuit breaker feeding the system (or both) will open up,...preventing physical damage.
Mike as you pointed out, the mfrs. nameplate rating of 9.5amps. I'm not sure how they obtain that, various mfrs. get their numbers in different manners. And as pointed out previously, one would only typically hit the maximum draw in very brief moments, quick enough to be inconsequential to the breaker. However, voltage drop can be an insidious effect,....robbing a system of it's capability at the exact moment it needs it most. It's a subtle, subtractive non-linearity, similar to compression. That said it's not real obvious until one is shown otherwise. So being mindful to stay away from your branch circuits maximum allowable current, helps retain system impact during playback of the huge, taxing low frequency effects. Just as other components posses linear envelope, so does the branch circuit feeding your sub system. Once again, headroom
is the answer.
Mike, I'm fully aware that you are well versed in this, as I believe we've discussed this. However, for others so interested, diminishing the effects of voltage drop is facilitated by larger gauge wiring, and shorter runs. If needed, a great system tweak is a dedicated circuit, with up-sized wiring. Assuring tight connections throughout the entire run, from the breaker, to the receptacle, is paramount. Nearly all failures/problems occur due to connections that work themselves lose.
Hope this helps, some of the issues I've encountered.