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I just received my amp ( listed below )....

HFi1000.1D - 1 x 475 @ 4 OHMS, 1 x 750 @ 2 OHMS, 1 x 1000 @ 1 OHM

My Drivers are 2 Dxi104 dvc ( 4ohms per coil ) 50-270 watts RMS - 540 watts peak.

Am I better off wiring these in series/parallel to get a 4 OHMS at 475 W, or go with all parallel and getting them down to 1 OHMS for the full 1kw? WIll the second option below work if I keep the gain all the way down or is it way to much and too much of a risk and I should stick with the 4 OHMS setup?
 

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Looking at that amps specs on Sonic's website (only one I checked and could be wrong) that amps power is rated at .95% THD so almost the full 1% aloowable to still get the cea 2006??? rating which leads me to think that these amps are overrated and that you will not truely see that 1000 watts. With that said I would still use the 4ohm wiring config and keep your subs pounding for the long haul.
 

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From looking at the specs it does not do rated power, so to get the most out of it and to have some gain adjustment you should wire for 1 ohm. Do not put the amp where it does not get air flow around it.
 

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Looking at that amps specs on Sonic's website (only one I checked and could be wrong) that amps power is rated at .95% THD so almost the full 1% aloowable to still get the cea 2006??? rating which leads me to think that these amps are overrated and that you will not truely see that 1000 watts. With that said I would still use the 4ohm wiring config and keep your subs pounding for the long haul.
I don't understand this argument.

Is there really any difference in wattage rating at 1% vs 0.95%? Looking at the many graphs of wattage vs THD for a lot of amplifiers, I'd say no. Aren't most amplifiers rated at 1% THD with 14.4volt battery? I understand that there exist that certain boutique amplifier brands may do it differently, but most others (Alpine, PPI, MB Quart etc) do it this way unless stated otherwise.
 

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I don't understand this argument.

Is there really any difference in wattage rating at 1% vs 0.95%? Looking at the many graphs of wattage vs THD for a lot of amplifiers, I'd say no. Aren't most amplifiers rated at 1% THD with 14.4volt battery? I understand that there exist that certain boutique amplifier brands may do it differently, but most others (Alpine, PPI, MB Quart etc) do it this way unless stated otherwise.

No there is no difference in .95% and 1% which is my point. This CEA certification stamping limits companies that want this certification to a MAX of 1%THD. At 1% THD your mids and tweets would be very distorted sounding. Subs frequencies can fair better at 1% THD but the lower the better. Basically by rating at 1% vs .5% an amp can achieve a higher wattage rating even though the end user may not LIKE the distorion levels if they were to run their amp at that 1% THD wattage level. That is why when someone bench tests most amps they tend to see less output then rated because they are keeping the gain just below clipping which would cause distortion.

Just for example my late 90's Sound Stream ref 405 is rated at 0.1% thd and is very well known for being extremely clean which allows you to run it at higher volumns cleanly without the need for GOBS of power.

And just to be clear I am not saying that you won't get close to that power just that you won't like the distortion levels at that much power so most likely you would keep the gain down to where there is lower wattage then rated.
 

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I see. However, what I don't understand then is why so many amplifiers (may be most) are rated using 1%THD? It's not just maxxsonics.
 

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Because they can rate their amps at a higher wattage and still be able to become CEA 2006 compliant rated/certified. This little seal/stamp/sticker makes people feel warm and fuzzy so companies like to have it on their equipment. It was created to prevent the likes of companies like DHD that were claiming 3000 watts but were bench testing at 100 or so watts. Amps like that were being rated at very high THD levels with some up to 10% IIRC. Anything .5% and below you probably won't even notice any distortion caused by the amp but after .5% it can become noticable Some say not until 1% but everyone has different hearing capabilities along with a different perception of clean vs non-clean.
 

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FWIW if you look at older amps of quality, most were rated at .5% and below.
 
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