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moe53
12-05-2019, 08:10 PM
I will be using Yamaha RX-780, rated power 20-20KHZ, 2 ch driven, 95W. I like to listen to music loud. Should I have any concerns about getting loud enough? I could move up to 110W with a different Yamaha avr.
jimb
12-06-2019, 02:37 AM
I will be using Yamaha RX-780, rated power 20-20KHZ, 2 ch driven, 95W. I like to listen to music loud. Should I have any concerns about getting loud enough? I could move up to 110W with a different Yamaha avr.

I suspect you will be able to “get loud enough”, though quality of sound will be better with better amps. Maybe head over to the For Sale part of forum for some AMPS!;)

But, do not upgrade from a 95W receiver to a comparable one with 110W - that difference is too little to make a difference.
racrawford65
12-06-2019, 12:31 PM
Agree with JIMB - no significant difference between 95 & 110W.

Nice amps for sale in the For Sale part ;-)
moe53
12-06-2019, 01:28 PM
Agree with JIMB - no significant difference between 95 & 110W.

Nice amps for sale in the For Sale part ;-)
The next Yamaha model up from the 110W is 140W, RX-A2080. I think this makes a difference. Can you refresh me- what is the increase in db loudness as the wattage increases.
racrawford65
12-06-2019, 02:13 PM
Basic rule of thumb is that doubling the wattage results in 3db increase. Similarly, doubling the distance is 6 db decrease in level. "Doubling" of perceived loudness is around 10 db.

Decent article at https://www.musiciansfriend.com/thehub/understanding-wattage-speaker-efficiency-amplifier-loudness.

And a pretty good thread (including charts) on distance vs SPL at https://forum.blu-ray.com/showthread.php?t=151904

The CBM's are pretty efficient at 91 db @ 1 watt db / 1 m. How far away is your main listening position? You may be fine with the 95W RX-780. Looking at the pic of this on Crutchfield, looks like it has preouts for Fronts, so you could always add an external amp if needed.
jimb
12-06-2019, 02:37 PM
The next Yamaha model up from the 110W is 140W, RX-A2080. I think this makes a difference. Can you refresh me- what is the increase in db loudness as the wattage increases.

1.7 dB from 95W to 140W. It's not nothing, but neither will it sound much louder. If your AVR volume control shows relative dB as you change it, try increasing by 1.5 while listening. As noted by racrawford65, if you want "twice as loud" that means going from 95W to 950W. That is your peak limit. Depending on your type of music (how it is recorded and mastered), your average power runs 1/8 - 1/3 of that. You just want to avoid significant clipping during your loudest listening.

As a gross over-generalization, one of the issues with AVRs is that they don't "sound as good" as their power ratings suggest. This is largely held to be true by amplifier companies, and has been my experience as well, though for refined qualities of sound, not just loudness. Bass control, apparent bass extension, clarity, detail, ...
davef
12-06-2019, 04:37 PM
I will be using Yamaha RX-780, rated power 20-20KHZ, 2 ch driven, 95W. I like to listen to music loud. Should I have any concerns about getting loud enough? I could move up to 110W with a different Yamaha avr.

plenty of power for the 170s! At 10 feet back and with (2) 170's - you will be able reach peak volume levels of ~ 103dB, which is louder than I recommend anyone listen at. The difference between 95W and 110W is inaudible.