I am considering the VP150. but I note that its ohm rating is 4 ohms. I have an Onkyo TX-DS838 with JMLabs Cobalt 815 as my left and right which, I believe are rated 8 ohms. What is the significance of the difference between the ohm ratings of the speakers? Do I risk a higher level of a blown center channel due to its less resistance? Does this make my proposed combination incompatible?
The impedance rating of a loudspeaker is a difficult thing to bring down to a single number like 8 ohms or 4 ohms. The impedance of a loudspeaker varies widely with every frequency. The minimum impedance along the entire frequency range is probably the most important number but what frequency this minimum impedance occurs at would be equally as important. All this needs to translate back to the real world volume level the amplifier may go into protection mode at, which is all that matters in your listening experience. Add to this that different amplifiers are more sensitive to lower impedances and it gets even more confusing. As for your situation you will not have any problem with the VP150, as far as 4 ohm rated speakers go the VP150 is a very easy load for the amplifier, probably easier than the majority of 8 ohm rated speakers on the market.
Ian Colquhoun
President & Chief Engineer
I just received my Epic Home 80 set-up yesterday, and the imedance ratings on the back of the loudspeakers is different than what was reported in your product pages. What is the actual impedance of these loudspeakers, and why the discrepency?
Ian: I am still agonizing over whether to buy a matching center for my JM Labs left and rights or go with the VP 150. Conventional wisdom says that you buy a sonically matched center or else risk not having a seamless sound. But I wonder whether one can hear this difference, especially when the cost difference between the VP150 and my matching center would be $250. In the real world do people actually hear the differences between the type of sound produced between speakers when they don't have comparisons to make between speakers in their living rooms?
The impedance of the M80s is 4 ohms. The VP150 and QS8s are 6 ohms. This will all be in line soon in all the literature and the speakers. The VP150 and QS8s could technically be called 4 ohm speakers because of the minimum impedance at one small frequency bandwidth but in reality they act like 6 ohm speakers.
Ian Colquhoun
President & Chief Engineer
Timbre matching is really the key to a good system up front. If the JM labs are a neutral loudspeaker design this will help in making them a good match with the VP150. I think you will be OK if this is the case.
Ian Colquhoun
President & Chief Engineer
i would like to audition the vp150 for a center channel, but i have a yamaha htr-5440. my reciever doesnt compare to the onkyo, so i wonder how my reciever would handle the vp150. what would be the negative effect on my reciever, if any?
No problem with the Yamaha and the VP150. The Yamaha amps are very stable and the VP150 is a very easy load for a less than 8-ohm speaker.
Ian Colquhoun
President & Chief Engineer