Been a lurker here in a-gon, but since I recently purchased a HK 990 here in the Philippines, I thought I'd chime in with a short take:
As a backup story, I initially was interested in the amp when I heard the HK 980 that my father in law purchased in one of avshop's stores. As rated it was 2 x 80, with a high current rating (~80amps according to the data sheet), with MM phono stage to boot. When we set it up with high B&W 683s, the sound was quite muscular, but not very glaring, as what you may have with some solid state gear. Not as laid back as NAD, but not unlistenably sharp.
But I also found out that Harman had a top of the line model, the HK 990 that looked like one hell of an amp with it's dual mono setup.
The specs were compelling - 150w x 2 @ 8 ohms, 300 x 2 @ 4 ohms (perfect for my Dynaudios), HCC rating of ~ 200 amps, built in DAC and MM/MC phonostage.
So, I committed one of the mortal sins of someone in the audio hobby: I ordered an HK 990 without the benefit of an audition, based purely on specs and a few reviews on the net. . .
And the damn thing wasn't cheap, so I sold virtually all my stuff just to accomodate it. I figured it would be a one box solution to the ever-growing tangle of equipment that I had.
So out went the VDAC, the excellent i30 Dared Tube amp, my NAD phonostage, a DIY chip amp and a couple of other stuff. . .
The HK 990 has several modes that you can use for setting up:
1) Analog in --- DSP sampling of analog input to enable tone control & room correction --- translate back to analog
2) Digital in using its built in AD1955 DAC boards - - - same DSP control - - - translate back to analog
3) Analog in - - - Pure Direct mode which means no tone controls etc - - -Analog out
The first taste of the sound of the HK 990 was when I and 2 of the store's stuff unpacked it and connected it using setup mode # 1, using an iPod and a CD as a source. . . with the B&W 683 connected so I could reference it to the HK 980. I was afraid I blew money on a more expensive HK 980. . .
I could not have been more wrong. . . the HK 990 sounds nothing like the HK 980. And nothing like anything else in avshop's shop. It's rendition of Magnificent 7 Theme song was nothing short of jaw dropping, at least for me. My initial thought was : "wow, so that's what the B&W 683 should sound like when playing orchestral music." Very muscular, wider soundstage, but the bass drivers held firmly in control by the HK 990, which means to say no flabby bass. The shop could probably sell a truckload of B&W speakers if he used this as a demo setup. . .
We also noticed that the amp got quite hot in our short 30 minutes of checking it out. Must be a Class A stage there somewhere. . .
The shop's guys also noted that the tracks of CDs they played seemed to be presented better, in fact, to a level much higher that what they had heard before.
Anyways, I paid up the remaining balance and took the amp home. I broke it in further by playing background music all afternoon, but the serious listening test took place at 11:30pm. . .
Since I play most of my music in digital format (320kbps AAC) via my Apple TV, I used setup mode # 2.
So, what was the sound?
Suffice to say that, as I flipped through my music collection randomly, some things came to mind:
1) This amp retrieves a lot of detail, almost headphone-like. Not like my Grade SR60i, but at 6 feet from the speakers it comes uncomfortably close.
2) Whoever said that Dynaudios need beefy amps to sound their best. . . was absolutely right.
3) Upfront, detailed sound, but somehow not one glaring nor fatiguing.
4) No tube lush, but the detail and tight bass I got more than made up for it.
5) It's as if the amp was continuing a lesson it showed earlier with the 683s - boy, this is how your Dyns should sound like. . .
6) I did not seem to miss my tubes one bit. . . . in fact to paraphrase one of the reviews of the amp, it seems like halfway between a very good SS amp and a very good tube amp. It has control of the music, brings out details, and yet seems quite warm, literally and figuratively. The only amp I can think of that sounded quite similar was an Electrocompaniet ECI-3 that I auditioned once.
The phono section seems to have a higher gain vs my NAD-PP3 amp. A bit upfront, but maybe the amp is merely revealing limitations on my cheapo TT setup (Technics P-mount turntable bought for the equivalent of USD60).
Source direct sounds like the DSP processing still on, so I leave it at DSP processing.
Room correction I have mixed feelings. I felt my subwoofer integrated better using connected to the speaker outs and manually set, vs the auto calibration of the HK. YMMV however.
As of now, 2 thumbs up for this amp. Thinking of a speaker upgrade. . . a Harbeth or a Spendor perhaps?
Thanks!
