Looking for Power amplifiers with built in A/B speaker switches

usually, the 2nd pair of speaker terminals is limited to avoid any low impedances, so you might be smarter to find a Niles Speaker Selector, and that lets you have far more options choosing an amp,

and if the amp has two out, you use the main ’A’ out which is good for 4 ohms, then the switch sends to A or B without limitation

https://www.hifishark.com/search?q=niles+speaker+selector

this is simple, up to 14 awg screw terminals, no volume control

https://www.ebay.com/itm/297805435677?mkrid=711-53200-19255-0&campid=5338381866&toolid=10001&customid=2b401658-d2ca-11f0-83f7-653130323763

some look good, but always check the back panel, might be spring terminals, or custom connector that has been lost.

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this says it can handle 250 wpc/4 ohms, and has meters, real connectors on the back.

https://www.amazon.com/Fosi-Audio-Amplifier-Visualizer-Component/dp/B0CZRMSHJB/ref=sr_1_6_sspa?sr=8-6-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9tdGY&psc=1

usually, the 2nd pair of speaker terminals is limited to avoid any low impedances, so you might be smarter to find a Niles Speaker Selector, and that lets you have far more options choosing an amp,

 

@elliottbnewcombjr  - If you are saying there is protection circuitry in the B speaker terminals, I've literally never seen this.. I don't think the Niles switch is a bad idea, but I have never seen a single amp or integrated amp with both A/B speaker switches and extra protection or limits on the second. 

It's usually more like a a label that says something like: "Minimum 4 Ohms if 1 pair, 8 if two" 

If you think this is "usual" could you post a link to a couple of amps with this feature? 

Thanks for the input. I have never heard of a limit in impedances between A/B speakers posts. I'm never going to be operating all 4 speakers at the same time. I would think this being a switch it would 100% isolate the other set of speakers from the amplifier. I understand the amplifier itself has limits on impedances but that why I'm looking for a high current amp that can handle these loads.

Integrated amps often give you the choice of A, B or A+B.  So long as impedances are high and/or volume is low you are OK. 

Note that this isn't like a breaker/AC circuit exactly.  That is, if you keep the volume down you should be able to do A_+B, and if you turn the volume down while switching you will be OK.