Sound Quality
This is what it is all about of course. How does the amp sound? Well, having listened to it using a mix of cd's dvd's and High Definition files I do have to say that I have mixed feelings with this amp. On the one hand is sounds very much self assured and there is no denying that it has plenty reserve to drive my B&W N804's without breaking a sweat while having absolutely no digital signature. It is fluid and refined and never aggressive. It also has very powerful bass which in many setups will be a bonus. On the other hand it is so very refined and restrained that I find it lacking enthusiasm and liveliness. This amp seems to do its best in trying to avoid the typical 80's and 90's harsh and grainy sound and it succeeds amdmirably. This amp has the most fluid and strain-free treble that I have ever heard in a surround amp. It als sounds warm and mellow, like the stereotypical older English amplifiers, such as Quad. In fact, it sounds a lot like a Quad 405MKII but with more powerful bass anb more drive. But is this what you want from a home cinema receiver?
Me, I have double standards, I admit it. As regular readers know, for music I prefer refinement over drama, fluidity over attack and colour over sharpness. But even for my tastes, the HK goes a few steps too far. It sounds so very full, laidback and smooth that it simply fails to stir the soul, let alone impress with movies. It clearly doesn't lack power or control, for sure it has plenty power as is obvious from the way that it handles my Nautili but it just doesn't sound powerful. Is reminds me of the time when I compared an old Yamaha DSP-A1000 surround amp's poweramp section to a pair of Bryston 7B ST's. Mind you, the Yamaha is plenty powerful but the Brystons can supply 1000 watts. Each. Still, the Yamaha impressed me more despite its grain and its more aggressive nature. For movies it just sounded more dramatic. Well, the Yamaha was too much of a good thing of course but it just goes to show how a powerful amp doesn't neccesarily sounds powerful.
Things that make you go mmmm
Thus far we have an amp that is a dream to operate, looks fantastic and sounds good but maybe just isn't my taste. Okay, that's fine. If you use more dynamic/aggressive speakers than the B&W Nautilus 804's the results may be different. But what really surprised me was the regularity with which the internal fan would turn on. And when it turned on, it wasn't just on, it was like there was a mini-hoover inside! The only way that you would not hear it humming was if you cranked up the volume to uncomfortable levels. At first I figured that it must be that I have it setup in a tiny space with too little air around it. So I placed it in a different location, completely free with air all around it. Imagine my surprise when I had the movie on pause while I was doing something else and all of a sudden the fan came on at full power! This is just ridiculous. The amp was completely free-standing, idling (not playing any sounds), my room was not hot at all and still the fan came on. I have to tell you, this just sealed the deal. Well, it un-sealed it in fact. This was the reason that I returned the amp, along with the sound that I wasn't entirely happy with.
On closer inspection you could see that the heatsinks were made in a wind-tunnel kind of way. This is effective as long as the fan is on but without it there is hardly any passive cooling. This means that the fan is always on at a low rotational speed. And even then is it just audible, but low enough to not be a distraction.
On a last note, there was also a faint hum coming from the speakers at any volume level. This was audible from the couch at night, when there was no mucic playing. As soon as you played anything it drowned the hum. But still it is strange as no other amp I had ever had a hum this loud. Sure, most amps have some hiss when you put your ear against the tweeter but hum is rare. It may only be my unit but still I wanted to make note of it.
CONCLUSION
The AVR760 is a highly sophisticated surround receiver that caters for each and every popular surround format and function around. It also has unburstable power and big bass and is never aggressive. For me though it lacked some attack and bite. Not neccesarily sharpness, but a more forward sound with more drive would have been welcome. But this was in combination with B&W Nautilus 804 speakers which are admittedly a touch on the warm side. Things may be entirely different when using more forward, more accute sounding speakers. But besides the sound quality per se, there was another thing that Harman Kardon should really take not of and this is concerns the built in fan. The fan is always on at a low rotaional speed. But when the amp gets hotter, the fan speeds up. It turns out that it does this even when not playing music, when the amp has just been idling for a period of time and when it speeds up, it really speeds up! The fan is so loud that you couldn't possibly mask it except when playing music at uncomfortably high levels. So, all in all: great software and looks, let down by a thing so simple as a fan.