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A reward? How can you call something you pay for a reward? easy. It's a reward for being a discerning individual with standards so high that only the best will do. Because what I'm about to say goes against my traditional fear of the word 'best', even with the qualifiers I'll muster. force myself to This system is so, so special, so complete, so right that it undermines all you think you know about the replay of music in the home. But let's start at the beginning.
It dawned on me and Editor harris that, in all my years as a reviewer, I'd only ever written aboheels? Pass out one Krell product, and a cartridge at that, despite having used the products as my reference. At the same time, it dawned on us that a new approach to hi-fi assessment is needed if we (the journalists) are to be fair to makers who produce all or most of a system. Quite rightly, a product will only perform of its best if matched with components known by the designer to provide an optimal match. In the case of Krell, the company produces a source (CD), a range of pre-amps and a host of power amps. We left it to Krell to put together the package, stating only that we wanted to review not the killer, top-end set-up nor the entry-level system. We wanted a middle-of-the-catalogue hi-fi representative of the Krell philosophy.
What Krell supplied is enough to charge the batteries of even the most jaded audio casualty. At the very front, the MD-20 CD Turntable (Krell-speak for 'transport'), one from the top and selling for �4498, driving the Studio D/A converter, also one from the top and weighing in at �4231. This is fed into the KRC remote control pre-amp (�6380) and a brace of MDA-300 300W monoblocks (�10,710). The entire system is set up for balanced operation using Mandrake wire throughout, with the CD halves connected by AT&T and TOSlink optical and RCA coaxial, the latter accomplished with the latest NBS digital cable. Not wishing to start any pub-level arguments at this point, I'll say only that the coax massacred the optics, while the optics massacred the music. And that's confirmed by every visitor who heard the system.
The KRC pre-amp and the MDA-300s receive the full MC treatment on p??? in this issue, so I'll limit my remarks to the listening. Starting with the source, the MD-20 is the latest incarnation of the now-familiar Krell top-loading system, with the puck which keeps the CD from turning into a scythe. (I only lost one CD due to failure to place the puck on the hub. It's a lesson you need be taught only once.) Lift up the acrylic cover and there's a curved slit holding the swing-arm laser and ending at the transport's hub. The mechanism is the Philips CDM-1 Mk II, tried and tested and dependable. It's fully programmable, supports the FTS storage system for fave tracks, and is operable from a remote controller which adds numerical track entry to the basic functions on the fascia.
This player, by the way, sports the new look of Krell and Krell Digital uppper-level components. The light grey fascia is accented by black end sections and a black centre strip containing the logo. The lefthand section holds the on-off button and the read-out window for track and time information, while the right side contains the transport buttons covering every standard function bar the aforementioned numeric track entry. The look is simply sensational, clean and 'architectural'. When stacked on top of the matching pre-amp and D/A converter, the look is almost menacing.
Inside, the MD-20 betters the first-generation transports with new circuitry including an improved servo control, four-layer glass-epoxy circuit boards with better earthing for less noise and greater efficiency, and the option of TimeSync transport/processor sychronization which uses a second AT&T link to sychroniza all data and DAC clocks for the elimination of jitter-induced degradation. This wasn't fitted to the review sample, yet I can't imagine what gains it would provide a transport which strikes me as close to perfect.
Outputs on the review sample include the three types listed above, with AES/EBU (XLR) balanced output an optional extra. The transport rests on adjustable feet, but I used the Harmonix
Tuning Feet because I'm now paranoid about their absence.
In operation, the MD-20 is a gem, once you get into the habit of using the puck. It becomes doubly important after you learn that the MD-20 generates enough heat to make the puck stick to the disc. I decided to operate it with the lid in the up position, which means that -- should I ever forget to use the puck again -- the disco volante will provide me with a free appendectomy.
The Studio, like the MD-20 has the black-grey-black-grey-black front panel, with vertical rows of red LEDs at the edges. the left row indicates sampling frequency and emphasis, locking when the DAC receives a signal. The right row indicates which of the four inputs (AT&T, TOSlink, RCA coax, AES/EBU) you've selected. Inbetween are a source/monitor switch and LED indicators -- the Studio will feed a digital tape deck -- phase inversion selector with LED confirmation, and a button to select the inputs. The selection process is one which scrolls from 1-4. Socketry at the back is provided for all four types of digital input, single-ended and balanced analogue output and optical or coaxial tape output.
Inside, it's like enrolling at a military academy. Everything is so neat and tidy that you assume Dan D'Agostino is a Virgo with Virgo ascending. Krell wrote the software for the logic chips which control data recovery and clock synchronization. Two Motorola DSP-56001 chips are used, one per channel, producing a full 24-bit digital word for the DACs; user-replaceable EEPROMs contain the software, so upgrades to accommodate future algorithms won't require returning the unit to the factory.
Each channel uses two 20-bit DACs operated in push-pull configuration. With 24-bit input through 20-bit DACs the detail resolution is improved substantially. The push-pull configuration eliminates zero-crossing distortion.
The DACs' output is connected directly to the analogue output stages; there are no capacitors in the signal path and servo amplifiers ensure that no DC reaches the main outputs. The analogue section employs output amplifiers based on those used in Krell pre-amps: high bias, complementary Class A designs.
As you'd expect, instant synergy was achieved. I had the system up and running in under an hour, but the real listening didn't commence for another day; these products do benefit from a long burn-in period and require an hour or two from switch on even after they've settled in for the duration. The best advice is to leave the KRC pre-amp, Studio and MD-20 on at all times, though you may balk at filling the coffers of your local electricity board by leaving the MDA-300s idling...at 400W.
I said this was a system review, but that doesn't account for the speakers, of which there are none bearing a Krell badge. Instead, I opted for two which I know won't result in a stiff letter on Krell stationery: Apogee Divas and Sonus Faber Extremas. Both are critical, hungry loads which will test the MDA-300's grunt, and both are speakers with which I'm intimately familiar. I connected them to the Krell chain with NBS cables.
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