There have been too many occasions where I’ve seen a simple stereo 2.0 amplifier run circles around an expensive multichannel receiver. This is one of those topics that tends to annoy people, especially those who have invested serious money into a big home cinema setup. But hear me out.
I’ll start with a short story.
I used to work with a guy who was a bit of an audiophile and had put a decent amount of money into his system. He was running a Denon 7.1-channel beast, packed with so much tech that it felt more like a computer than an amplifier. He had nice Monitor Audio floorstanders at the front, a Q Acoustics subwoofer, and decent bookshelf speakers for the rears and sides (I don’t remember the exact model, but it was all good quality gear).
We used to chat about music during cigarette breaks, exchange tracks, debate sound quality, the usual stuff. At some point, I asked him how he listens to music when it’s just music, no films. His answer surprised me: he runs the full 7.1 setup.
I suggested he try a few things. Turn off the rear speakers. Turn off the subwoofer. His reply honestly fired me up.
“I have no bass without the subwoofer.”
What?
I knew those speakers well. Properly placed, they have very respectable bass. More than enough for music. And they were placed correctly in his room.
After a few more discussions, I finally told him to go and buy a simple stereo amplifier. £200–£300, nothing fancy.
“But I already have a £1000+ amp, why would I buy something else?”
At that point, after months of conversations about audio and repairs, he trusted me enough. I told him that if I was wrong, I would buy the amp from him myself.
The following Friday, I saw him carrying a box to his car. He had picked up a brand-new Marantz stereo amp, open-box, discounted to around £160 from £300. He had the whole weekend to play with it.
Come Monday morning, he was almost avoiding me.
Long story short: he was blown away. His speakers suddenly had bass. The soundstage was wider. The music felt alive. Better transparency, cleaner highs, more punch. I’m trying to use his words as closely as I remember them.
At this point, you probably have the same look on your face that he had: “What is this guy talking about?”
I’ll keep this at surface level and avoid going too deep into circuit theory.
First of all, yes, there are multichannel receivers that sound genuinely excellent for music. They exist. They are also rare and very expensive. Most consumer AV receivers are designed to excel at multiple tasks, rather than being exceptional at one.
The biggest reason for the difference is power.
A seven-channel amplifier typically has one transformer and one main DC power supply feeding all seven channels. Yes, the power supply will be larger than in a stereo amp, but you are still drawing power seven times from the same source. A two-channel amplifier may have a smaller power supply overall, but only two channels are pulling from it.
It’s also far easier to design a proper dual-mono stereo amplifier than it is to build a receiver with seven transformers, seven power supplies, and all the associated space, cost, and heat problems.
Why does power matter so much?
Because power delivery is not linear. One channel suddenly needs current for a bass passage. Another needs a fast transient for a snare hit. Each of these demands pulls from the same supply. When several channels do this at once, the supply gets stressed, and the channels start fighting each other. Think of it like multitasking on an underpowered computer: everything works, but nothing works optimally.
Multichannel amplifiers are the definition of “jack of all trades, master of none”. They are incredible for films, surround effects, and convenience. Bluetooth, Wi-Fi, room correction, streaming, HDMI switching – all brilliant. But music needs two channels. Music is recorded in stereo.
Another thing I personally dislike in many hi-fi receivers is the amount of processing. The signal goes through layers of digital processing, conversions, DSP, control logic, and switching before it even reaches the amplifier stage. By the time it gets there, it barely resembles the original signal.
This is where we often joke at The Audiophile DIY: a simple valve amplifier with a handful of hand-soldered components can wipe the floor with a “smart” amplifier packed with CPUs and firmware updates.
Then there’s the marketing magic.
Manufacturers somehow managed to create energy out of thin air. A 7.1 receiver advertised as “100 W per channel” sounds impressive. Seven channels at 100 W means 700 W of audio power. Even assuming generous efficiency, losses in the transformer, heat, and the rest of the electronics, you’d expect the unit to draw maybe over 1 kW at full output.
Then you look at the back panel.
Maximum power consumption: 500 W.
That’s usually when we laugh.
To give a real-world comparison, as I’m writing this on the train, a Pioneer SA-720 Blue Series amplifier is waiting for me at home on the workbench. It’s a small, lovely vintage stereo amp rated at 65 W per channel. That’s 130 W of audio output. Accounting for efficiency and losses, you’d expect maybe 200–250 W draw. The unit is rated at 340 W.
That’s an honest specification.
If you’re using a multichannel amplifier and you have decent front speakers, do yourself a favour. Borrow a good stereo amplifier from a friend. Try it properly. You might be very surprised.
Or you might decide I’m an idiot.
Either way, you’ll learn something.
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