QuestionHey there. I Have an issue that's causing me some grief as I haven't set up a system since I was a kid. I have a cheap 200 watt receiver with a speaker selector for a and b. I have 2 Polk 655dI speakers which each have stereo input and out, and 2 impedance matching volume knobs for outdoor use. For a source, I have an apple airport express using AirTunes plugged into the aux.
The output on the AirTunes is at 65-70%. Whenever I add the b or use the b solo, the receiver shuts off when it's at volume 10. I know it's an impedance thing but I can't figure out how to solve it.
Each speaker is rated at 8ohms. The receiver says 4-8 ohms for a. 16ohms for b or a+b. If the receiver costs $150 I doubt it requires $1500 speakers when you want to use the b output.
What am I missing that's most likely right under my nose?
Appreciate any help. Company coming over soon and promise the wife she'd have her tunes available.
Answer Perhaps you forgot to mention the indoor speakers you are using. While we are at it, the make and model number of the receiver would have been nice to know.
You may want to just run BOTH Polks on one channel outside and select mono output so that you will be at 16 ohms. Your other hardware option (speaker-wise) would involve a second set of the Polks (or other 8 Ohm speaker set) so that you could have 16 ohms per channel on B. No stereo operation of course but it should play all day long.
If the impedance load of B or A+B is not 16 Ohms, the unit will hopefully go into protection mode before it melts.
You can wire two $30.00, 8 ohm speakers per channel in parallel and get 16 ohms so $1500 dollar speakers are not needed for 16 ohm loads.
I have read that Apple aux outs are not that great and oftentimes have bass added (for the aux) which can/will cause problems with clarity, dynamic headroom and accuracy.
In the interim, do NOT use 10 on the volume control.
You may want to run the AirTunes volume at 50% and see what happens. Be sure that there are no signal processors enabled on the AirTunes if so equipped. I would still think it will shutdown due to the impedance problem, but it may play a little longer before it shuts down. You might consider using a laptop or a PC to drive the amplifier more effectively in that department.
JM
