Why did this 1975 amp sound so good?


A friend let me borrow a Tandberg TR2075, which I paired with a pair of Energy CF70 towers. 
 

With equalizer flat, the sound was considerably more energetic, lively, and with more energy. The bass coming from the 6.5” woofers was so substantial I could feel air moving from the towers’ front port. 
 

Fast forward to today, and the same speakers are on a Denon AVR-X4000. And, what’d you know, they do not have the aforementioned qualities the Tandberg provided. 
 

To keep the comparison apples to apples, I’ve let the towers play on the Denon full range similar to how they would have been when they were on the Tandberg. 

I kept the source the same with a turntable.

Am I going crazy here? Why was the sound much better with the older power?

Ag insider logo xs@2xi3eyond55

+1 @ogiboy Also Tandberg made some droolworthy cassette decks! BTW there are few used Tandberg receivers over on Audiomart you may want to check out.

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Is there such a thing as a cost effective 2 ch power amp I could connect to my Denon’s pre’s and expect the same result as the Tandberg?

imo tandberg is the best-sounding of all the 70s receivers. i briefly owned the 2045 and a 2055, both of which outclassed the yamaha/sansui/pioneer that preceded it, although the latter were more durable. @i3eyond55 you could try adding a tandberg amp like the 3003 to your denon (i've seen 'em around for $500 or so) and see how it sounds, though i suspect a tandberg amp + preamp would be more pleasing--synergy and all that.