IF 0.66 is the actual number you are measuring with multimeter, yes. Even the original HD amps can do that but have potential to fail if the following isn't known-
I don't know how but it got severely distorted when this rumor went around brazilian amps can play the lows well or however you want to word it.
Well, here is the ACTUAL truth behind what is going on-
On the original HD lines(and current amps below the hd8000)-
So, normal suggestion is do not clip over 14.4v and keep it wired no lower than stable ohm rating.
Well, user sets their gains perfectly.
The problem comes when they start playing modified music that peaks below 30hz. What happens is their is a light rolloff going down the FR.
Without changing the volume, if the signal amplitude at lets say 50hz is the same as 25hz on the song, then when it gets to 25hz.. IT will start clipping (normally).
User didn't adjust volume.. just letting it play. IF they are not paying attention, every time it drops low, its clipping.
Now, clipping is fine amp-wise BUT if they are clipping at a high enough voltage... Then those low frequencies when clipped are actually forcing the amplifier to produce more power than it's designed for.
So, in these cases, poof, the FETs pop.
The HD8000 eX, HD15000 and Bass 12k have upgraded FETS in comparison to the other HD amps power ratings to FET ratings so users can wire them below 1ohm for competition and get large wattage numbers out of them without them popping in few seconds.
They ALWAYS played low. A local friend of mine ran his original HD8000 on modified music down to 17hz but when it dropped, he also had bad DC voltage drop too so since he was so used to combating that(low voltage causes amps to clip sooner as well), he was used to turning it down a click or two on songs like that.
In the statements i've made previously about them being able to do 0.5ohm. These are suggested on a burp.
I have charts here which show estimated rail voltage across different impedance and all DC voltages with Amperage threshold not to exceed.
When looking at it, running at 0.5ohm.. if daily, it MUST be on low voltage and the source material must not be modified near 0db bass lines which implies you need decent impedance rise as well.
3x impedance rise on modified music and 2-2.5x impedance rise on normal music.
This is because the current output threshold for sustained use is easily exceeded if reactive load is pegging 1ohm or lower and the input signal is maxed out at the time (clearly visible if clipping but can happen before clipping as well).
I'm willing to almost bet that no one here knew the hd15000, for example, is also rated at 18,000w 1ohm at 15.8v.
The sweet spot on these amps appears to be high voltage, around 15-15.5v with a reactive load between 2-3 ohms.
You should easily, on the hd15000, be able to get to 10,11,12 and even 13kw output and not risk clipping it hard at these levels.