Would you be able to explain what this means? I'm still growing in my understanding. Thank you!
I am not sure anyone know for sure what nominal means when used in an audio amplifier. According to the Cambridge Dictionary, it can mean different things but really doesn't mean much.
https://dictionary.cambridge.org/dictionary/english/nominal
Aside from that, the Yamaha owner's manual does not use the word nominal at all. It simply stated:
1 V/1.2 kOhm.
Page 145:
https://usa.yamaha.com/files/download/other_assets/1/436251/RX-V779_RX-V679_om_UCRABGLFH_En.pdf
That means you get 1 V if the impedance of the load, in this case the input impedance of the power amplifier, is 1.2 kOhm. I guess Yamaha picked that number probably because it only takes about 1 V to drive the internal amps of the unit to it's rated output, that is a mere 95 W, not hard to get there at all.
We all know the input impedance of a power amp is typically much higher than 1.2 kOhm, so theoretically, even if the input impedance of your power amp is on the low side, say only 24 kOhm, the pre out voltage could be as high as 1 X 24/1.2 = 20 V. We all know that is not going to happen, but it is reasonable to expect the Yamaha could output much higher than 1 V in real world applications. That is, when driving a power amp that has much higher input impedance than 1.2 kOhm.
Based on several of Gene's bench test results over the years, my guess is that the RX-V preout should be comparable to that of the RX-A860 (recently tested by Gene). It wasn't great at all, but good enough for power amps that has reasonably high sensitivity, say at least 28 dB, and rated <200W. For amps rated for >200W and/or have lower sensitivity, those entry level RX-V/RX-A receivers should be avoided.