Quad: The Middle Ground

[par4ken]

Not to go down a rabbit hole, but the pure math and physics of power do not translate directly to human perception.

You could look it up.

Perception of volume is always subjective and depends on one’s own hearing but generally speaking, an increase of 10 dB roughly corresponds to the perceived volume doubling in intensity. Thus, 60 dB are perceived as twice as loud as 50 dB.

https://www.connecthearing.com/blog/hearing-protection/volume-and-decibels/

Yes and a 10 dB increase corresponds to a 10 times increase in power. Just as 3 dB is a doubling of power and 20 dB is 100 times the power!

https://www.redcrab-software.com/en/calculator/electrics/decibel-voltage-power

 

[Electric Moo]

I jave a few older 70s receivers and have SMv3 on backorder. When it coming in ill hook up my kenwood 120wpc with the SM but i also have a San. QRX 7001 that needs restore. Which i hope to send out soon. Also have a QS 500 rear channel amp hooked up to San. 3300 with 4chann adapt outputs. Its a 1st gen decoder but sounds nice with 2pr of Dynaco a25s. But 4 channel has grabbed me by the balls. I cant go back to stereo and be completely satisfied again. Time to sell the vintage 2 channel and buy a properly restored qrx 9001. With 2 pr of Forte lls. Enjoy the music !!

Wow, so you've ordered a SM and are planning to get a QRX9001 too?

Awesome!

 

[Doug G.]

Who needs rules and specs.? We TRUST OUR EARS, the MOST accurate, MOST consistent, measurement devices ever created!



Doug

 

[kfbkfb]

Circling back to the original question, I'd use the 1% THD power number, 10% THD may be audible in some types of music.

Of course, there's always the "monoblock" single channel amplifier option, then there's no shared power supply limit.


Kirk Bayne

 

[MidiMagic]

I mean, come on. Two channels driven. One channel driven. IDK. Someone decipher this mess for me.

View attachment 88518

Different legal standards of how to represent the power of the amplifier in different countries.

There might be a slight effect from using different line voltages and frequencies to power it.

 

[Sal1950]

Interesting title though. Whatever amount of loud is too loud I reached it over 50 years ago. My ears have been ringing non stop ever since.

Charlie never respected a time-out for us to put in ear protection.