Here’s a new model that claims it can handle 2 ohms.This amp goes backwards in to 2ohms!!, like I said above with the NAD reference Spec sheet for Icepower 700ASC specifies 2.5ohms minimum.Same deal with this, what it’s true 8ohm, 4ohm, 2ohm "wattage figures"? do it "increase significantly" (almost double) as the impedance goes down. This indicates an amp that will drive effortlessly the OP’s kind of speaker to it’s full potential. Cheers George |
That was my point George, someone mentioned the Stellar M700 goes down to 2ohms, and the specs are only 2.50ohms. It's also interesting that Stereophile didn't bother reporting specified power rating at 2ohms, but did mention THD rises into 2ohms at higher frequencies. Like everything else, you get what you pay for and there is no free ride with Class-D amps (with reference to low impedance speakers). We define clipping as when the percentage of THD+noise in the amplifier's output reaches 1%, and fig.5 indicates that the M700 slightly exceeds its specified power of 350W into 8 ohms (25.44dBW). Into 4 ohms (fig.6), the M700 clips at precisely the specified 700W (25.44dBW). Fig.7 plots the THD+N percentage against frequency at a level at which I could be sure I was looking at distortion rather than noise: 20V, which is equivalent to 50W into 8 ohms, 100W into 4 ohms, and 200W into 2 ohms. The THD is very low at low and middle frequencies into 8 and 4 ohms, but does rise into 2 ohms and at high frequencies. Read more at https://www.stereophile.com/content/ps-audio-stellar-m700-monoblock-power-amplifier-measurements#rLo... |
It's also interesting that Stereophile didn't bother reporting specified power rating at 2ohmsYes this is always and indication, that it's not happy doing those loads, it may handle them and make some noise into them, but then so can the NAD3020 integrated, can they get the best from the OP's CS5's? I doubt it very much. Cheers George |
It's also interesting that Stereophile didn't bother reporting specified power rating at 2ohms, but did mention THD rises into 2ohms at higher frequencies.This is true of all amplifiers; if high fidelity reproduction is your goal, lower impedances should be avoided so as to reduce distortion from the amplifier. The distortion generated by driving a lower impedance is mostly higher orders and is audible as brightness and harshness. You really don't want to make any amplifier work hard to drive a 'difficult' load. The result can be seen in measurements of any amplifier. |
