Integrated Amplifiers

Harman Kardon HK 990 Integrated Amplifier and HD 990 CD Player



The HK 990 and HD 990 are certainly befitting products from a company with numerous design awards. The overall look of both components is clean and modern, with sharp lines contrasted by gently rounded corners. While some may find the front panel designs "minimalist," I absolutely loved them and feel that the design theme will age extremely well. In a bit of a contrast to the current all-black (or all-silver) theme most companies have adopted, the units both sport a two-tone design of gloss black top halves with a dark pewter bottom half. While I typically prefer all black myself, I really liked having this bit of extra flash in my equipment rack. As a testament to the beautiful design, numerous houseguests commented that the HK 990/HD 990 looked very expensive. Also drawing numerous "oohs and aahs" were the white lighting on both components when powered up. The volume control knob on the HK 990 is particularly neat, with its white light illuminating the volume knob from within.

My only criticism of the design of both units' centers is the front-panel buttons. Frankly, the labeling is impossible to see in the dark and since all of the buttons are the exact same size and shape, you can't identify them by touch either. Being that most users will typically use the remote control, this is a minor issue, but one I feel I must mention. Speaking of the remotes, the unit included with the HK 990 is an interesting design. The remote is not the most comfortable to hold, but there are buttons for every function I ever needed, including a dedicated button for the "EQ Preset," which I'll cover later. The HK 990's remote can also control the HD 990 and is missing only one button from the HD 990: "source." It can be programmed to control numerous other components as well. The remote for the HD 990 is simpler, but is far more comfortable to hold. It includes everything one would expect from a CD player remote, including dedicated buttons to help you move through folders of MP3s. To be honest, I never even had to use the HD 990 remote as the HK 990's was able to do everything required for both devices. My biggest complaint with both remotes is that they aren't backlit, so they are very hard to use in the dark.

The back panel of the HK 990 is well equipped. There are 7 analog RCA inputs, plus 1 phono Moving Magnet (MM) and 1 phono Moving Coil (MC). There is also a single pair of balanced XLR connectors for use with the CD input only. This is a truly balanced, dual-differential design. The RCA input labeled "Processor" is basically a home theater bypass and passes the incoming signal directly to the HK 990s amplifier section at full strength. There are two subwoofer inputs that can be utilized with the home theater bypass functionality as well. On the digital side of things, there are 2 coaxial digital inputs and 2 optical digital inputs. There is also the proprietary HRS-Link connection, which looks just like a standard Ethernet port. There are RCA pre-outs for the left and right channels as well as two subwoofer channels, which is a very nice touch. The EZSet/EQ can calibrate the system for two subwoofers, which could be very useful for those of you running more than one sub. There is also a coaxial digital output as well as two other RCA record outputs. Rounding out the connections is an RS-232 control, IR in/out, and two 12v subwoofer triggers. The HK 990 can also be used to drive two pairs of speakers via the four sets of well-built binding posts. However, if you wish to run two pairs of speakers make sure that they are both 8 ohm or higher loads; otherwise you could damage the amplifier section. The only things missing are USB (asynchronous), RJ45, and iPod connectivity. I can definitely see some users wishing they could send their computer/network-based audio directly into the HK 990.

The HD 990's back panel has a few more options than most CD players I've used. Besides analog RCA, HRS-Link, coaxial digital, and optical digital outputs there is also a fully balanced XLR output (with dual Diamond Class A output stages) which is rarely seen on a player in this price range. Of further interest are the coaxial digital and optical digital inputs. The HD 990 can take a digital feed from other source components with lesser quality DACs, convert them to analog using its own Analog Devices AD1955 DAC, and then pass them along to the HK 990 or other connected device.

Build quality of both components is excellent. My first surprise of this review came when I went to retrieve the HK 990 from my front porch after it was delivered. I hadn't checked all of the specs on the unit yet, so I was expecting a normal mass-market 25 pound 2-channel "receiver." Well, the shipping weight on the HK 990 is closer to 50 pounds, so the laugh was on me. Wondering if they packed a bit of lead in with the amplifier, I tore the box open and checked things out. No lead could be found, but it was pretty obvious that Harman Kardon hadn't taken any shortcuts with this thing. The HK 990 is beautifully constructed, with absolutely no flex to the chassis whatsoever. Fit and finish is excellent and in line with a product of this price. The center of the chassis contains two large heat sinks/air channels, which keep the amplifier cool.

After removing the top plate of the HK 990, I could see that the internal construction is up to snuff as well. The two toroidal transformers are massive (16,000µF of supply filtering per channel), and the circuit board layout is neat and clean. Component quality appeared to be first-rate as well. A lot of thought went into the internals of the HK 990 including dual-path technology for allowing pure analog and pure digital audio processing within the same chassis, dual differential input stages with their own high-voltage supply, a cascaded pre-driver stage to reduce high-frequency distortion, thermal tracking to bias the current of the output stage in real time, and a DC servo to ensure that the DC level of the amplifier output remains within a set limit. It has been a long time since I have seen this level of quality construction from a "mainstream" manufacturer.

The HD 990, while not having the mass of the HK 990, is also nicely built. The chassis is solid, and the CD drawer is quiet and smooth without displaying the "chintzy" feel that so many plastic drawer trays have today. My only quibble revolves around the HK 990's volume control knob. While I loved the white backlighting, the plastic knob itself has a fair amount of play and wiggle to it that just doesn't match up with the overall quality of the rest of the unit. I'd like to see something a bit sturdier in the future.