I recently watched a very educational discussion about Amplifiers that was presented by Mr.Gene DellaSala
I own a complete JBL home theater system (Northridge series - Front L/R - ND 310ii (250W) , Surround L/R N38ii (175), surround back N-Center L/R (150W) , Center -S-Center (150W) and PB10 10
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150W) subwoofer.
The whole setup was powered using a Harman Kardon AVR 525 (7.1) receiver.
"Audio Section Stereo Mode Continuous Average Power (FTC)
85 Watts per channel,20Hz–20kHz, @ <0.07% THD,both channels driven into 8 ohms
Seven-Channel Surround Modes Power per Individual Channel
Front L&R channels: 70 Watts per channel @ <0.07% THD, 20Hz–20kHz into 8 ohms
Center channel: 70 Watts @ <0.07% THD, 20Hz–20kHz into 8 ohms
Surround (L & R Side,L & R back) channels: 70 Watts per channel @ <0.07% THD, 20Hz–20kHz into 8 ohms
Full Disclosure Power (all channels are driven simultaneously)
Frequency Response @ 1W (+0dB, –3dB) 10Hz –100kHz
High Instantaneous Current Capability (HCC) ±45 Amps
Transient Intermodulation Distortion (TIM) Unmeasurable
Slew Rate 40V/µsec"
As an upgrade in 2018, I bought a Marantz NR1606 (7.2),
"With discrete circuit technology, the power amplifier provides identical quality for all 7-channels (70 Watts x 7-channels) For optimum realism and stunning dynamic range, the power amplifier section features discrete power devices (not integrated circuitry). By using high current, high power discrete power devices, the amplifier is able to easily drive high-quality speakers. "
Power amplifier Rated output: Front: 50 W + 50 W (8 Ω/ohms, 20 Hz – 20 kHz with 0.08 % T.H.D.) 70 W + 70 W (6 Ω/ohms, 1 kHz with 0.7 % T.H.D.) Center: 50 W (8 Ω/ohms, 20 Hz – 20 kHz with 0.08 % T.H.D.) 70 W (6 Ω/ohms, 1 kHz with 0.7 % T.H.D.) Surround: 50 W + 50 W (8 Ω/ohms, 20 Hz – 20 kHz with 0.08 % T.H.D.) 70 W + 70 W (6 Ω/ohms, 1 kHz with 0.7 % T.H.D.) Surround back: 50 W + 50 W (8 Ω/ohms, 20 Hz – 20 kHz with 0.08 % T.H.D.) 70 W + 70 W (6 Ω/ohms, 1 kHz with 0.7 % T.H.D.)
Since my speakers were rated at 8 ohms, the new amp is only able to push at 50W max. My assumption was I truly didn't push the HK 525 hard to get the volume to a good level. But the Marantz NT 1606 couldn't match the output at the same db levels of volume.
Is it because of the 70W vs 50W difference?
why am I seeing almost all receivers specifying its capabilities, in multi-channel receivers as below? 2 channels drive?
"140 watts per channel into 8 ohms (20-20,000 Hz) at 0.08% THD, with 2 channels driven."
How do I consider/find a perfect replacement for my HK-AVR 525 7.1 Receiver?