I am looking to buy a receiver for a pair of Angstrom Omega 5s (bookshelf), the speakers have a nominal impedance of 6 ohms. I was looking at a HK AVR 130/230 and the specifications are for 8-ohms. So I asked the sales person at bestbuy if my speakers would work with the receiver, he gave me a 'deer in the head lights' look - shortly after he said he would get someone more experienced to address my concerns. After 15 minutes of waiting around I decided not to make an uninformed purchase and left the store.
So my question is, how can you tell if a receiver will work with a 6-ohm load? (Specifically the HK AVR130/230)
HK may help, but you may have better luck in contacting Angstrom and their website--as it is their speaker and speaker manufacturers normally test their products on numerous receivers to check out receivers ability to drive their product.
Still, many speaker manufacturers are loathe to comment on receivers--either because of ignorance (they haven't checked out many receivers) or they don't want to be partial or point out weaknesses.
I have had several and currently own an HK surround reciever. I can tell you that HK recievers will drive most 4 ohm speakers currently on the market with ease. In fact i have mine wired to a pair of DCM kx10's which have a nominal impedence of 4 ohms. the diffrence betwwen 6 and 8 ohms is minimal so i would not sweat over it. If the Angstroms have a decent sensitivity around 90 dcbl or higher, they should pose no problem for the HK. What you have to be careful about is speakers like Polk Audio which have a low sensitivity and a low impedence which usually spell trouble ,especially at high volumes,for all but the most powerful receivers. Keep in mind that in a typical speaker rated a 8 ohms, this impedence will vary widely. It could be as high as 16 or 20 ohms at high frequencies or dip as low as 5 or 6 ohms with low frequencies. The 8 ohm rating for most receivers is the industry standard that is used to meet the minimum UL listing criteria. Just because a reciever is rated for 8 ohm speakers does not necessarily mean that it will not drive speakers with a lower nominal impedence. E Ramsey AAS industrial electronics