speaker-to-receiver connection question

[DaRealzG]

I have had this question in my mind for a while. I found this site today, and registered immediately. So, I finally let this one out of my chest.

I have a pair of 4-ohm impedance speakers that I wanna connect to my receiver(Aiwa AV-D57) for stereo playback. The receiver's user's manual mentions no information on a recommended speaker impedance range. The receiver came with a set of five speakers rated at 8 ohm. I know connecting a 4-ohm speaker will put more stress on the receiver, but I don't know if my receiver will handle it. I asked a guy at Aiwa technical support, and he said "the receiver will be OK, but we don't recommend that you connect them." What confuses me more is that the receiver's "set-up instruction" manual has a diagram of back panel of the receiver, which says "8ohm/4ohm" under the front speaker terminals. However, it only says "8ohm" on the actual back panel of the receiver. So, surely, the manual says it's OK to connect a 4-ohm speaker, but the receiver only says 8ohm speaker; that's an inconsistency in between product documentation and the actual product.

Generally, is it OK to do this? The receiver is like any home theater system ones with AM/FM tuner, Dolby Pro Logic, Dolby Digital, and a bunch of connectors for other audio devices.

I can't wait till I try my speakers on this receiver, but I don't wanna risk the chance to mess up the receiver.

I would appreciate any comments.


John

[karl k]

In a nutshell, you'll be alright IF you don't crank it. The impedance determines how much current the amp will pass to the speakers. The amp/receiver is designed to pass a certain amount of current and as long as you don't exceed this, the amp/receiver will run normally. Those receivers with digital readout for the volume are easier to use in this case as the difference between running 4ohm and 8ohm is about 3db on the volume control. So all you would have to do is set the volume to your regular listening levels with the 8ohm speaker and set the volume 3db less for the 4ohm speaks. More than likely, the receiver will have a thermal shutdown and current limiting to help insure the receiver doesn't fry, but it's best not to test this too very often. Depending on the efficiency ratings between the 2 sets of speakers, you may or may not see/hear a change in loudness when doing this.

I asked a guy at Aiwa technical support, and he said "the receiver will be OK, but we don't recommend that you connect them."

All he's saying is if they recommend you do it, and the receiver fails, it's on them... but most times it will work.

What confuses me more is that the receiver's "set-up instruction" manual has a diagram of back panel of the receiver, which says "8ohm/4ohm" under the front speaker terminals. However, it only says "8ohm" on the actual back panel of the receiver.

Specifications subject to change...blah blah blah!

[DaRealzG]

Thank you for your input, Karl. I"ll probably wait till I get a new amp/receiver to try the speakers.