Product Review -
Millennium 2.4.6 DTS Decoder/Preamplifier - April, 1997
By John E. Johnson, Jr.
Click to see
Millennium 2.4.6 DTS
Decoder/Preamplifier; DTS decoder for 5.1 sound; Analog
inputs/outputs: Six pairs of RCA jacks; Digital inputs: one RCA
75 Ohm, one TOSLINK optical; One coaxial digital 75 Ohm RCA jack
output; DTS decoder: Motorola 56009 (upgradable); DACs: three
stereo 20 bit Delta Sigma; Digital filter: 8X; S/N 110 dB; Trim
± 15 dB; Master volume ± 30 dB; 12 DC power supply; Size
2"H x 17"W x 6 1/2"D; Weight 7 pounds; Black metal
chassis; $699; Millennium Technologies, P.O. Box 8359, Incline
Village, Nevada 89452-8359; Phone 888-551-6789; Fax 888-515-0123;
Well, if you have paid attention to our suggestions to purchase receivers or processors that have a set of discrete 5.1 inputs for outboard decoders, now comes the payoff. 5.1 Marketing and Millennium Technologies have released their Millennium 2.4.6 DTS Decoder, which can also serve as a preamplifier. The 2.4.6 means that the six channels of 5.1 sound can be "downmixed" to 4 or 2 channels if you don't have the necessary power amplifiers to play each channel individually.
The Millennium is very compact and solidly built. It has an external 12 V supply to keep the line AC away from the decoder. This is also useful if you want to put DTS in your car, since all you need to do is connect the decoder to the car battery. The front of the unit has a small on/off toggle, a blue LED to indicate power on, another blue LED to indicate lock on the DTS digital bitstream, three small trim pots for center, rear left/right, and subwoofer, a master volume control, and a toggle for automatic or manual input sensing. The rear has all the analog and digital input/output jacks, a jack for the 12 V DC power supply input, and eight dip switches for setting the default manner in which the unit operates, such as downmixing (we used the factory default settings, with all switches in the up position.)
Putting an outboard DTS processor into a home theater system can be tricky. The Millennium has made the task easier, if you have an outboard AC-3 processor (as we do), by the use of analog input/output jacks that connect together when the AC-3 is being used, and connect the output with the DTS of the Millennium when DTS is being used. The RF output of the laserdisc player continues to go to the RF AC-3 input on the AC-3 decoder, but the six analog outputs of the AC-3 decoder now go to the six analog input jacks on the Millennium. The six analog RCA jack outputs of the Millennium go to the 5.1 inputs on the receiver. A Toslink optical output of the laserdisc player is connected to the Toslink optical input on the Millennium. (You can also connect a dedicated CD transport to the digital coax input on the Millennium if you want to play the CDs from a CD player instead of the laserdisc player.) We set the auto/manual toggle on the Millennium to "Manual". Now, when the laserdisc has an AC-3 output, the six analog outputs from the AC-3 decoder trip the solenoids on the Millennium, and the analog AC-3 outputs are fed through to the receiver. When a DTS signal is detected by the Millennium, the solenoids switch so that the analog DTS output is sent to the receiver at the same 5.1 inputs. On the Yamaha RX-V990, which we used for our tests, this allowed us to use Pro Logic, and then 5.1 Discrete for AC-3 and DTS, with the appropriate signal being detected and routed by the Millennium. The trim pots on the Millennium work only with the DTS output. This allows the user to set the volume of the DTS independently of the AC-3, which means you won't get an unpleasant loudness surprise when using AC-3 vs. DTS. (They can be set to the same levels if you wish.)
The DTS software is pretty scarce right now (April, 1997), but it is growing quickly, with both DTS laserdiscs and DTS CDs becoming available. We had the following DTS CDs on hand for the test: "Alan Parsons on Air", "Pavarotti & Friends for War Child", Marvin Gaye - "Forever Yours", Steve Miller Band - "Fly Like an Eagle", "The Storm and the Sea", "Surround Sound for the Millennium", and "DTS Music Demonstration and Set-Up Disc". For laser, we used "Jurassic Park" DTS version. The Yamaha RX-V990 receiver, DDP-1 AC-3 Decoder, Yamaha CDV-W901 Laserdisc Player, McCormack Digital Transport, Audio Alchemy Digital Transport, Carver AV-705 Power Amplifier, AudioQuest Cables (including the OptiLink Z Toslink), Nordost Flatline Cables, Krix Speakers, and Eminent Technology Speakers, were utilized as the equipment package.
DTS provides six discrete channels of 20 bit audio: Front left/right, Center, Rear left/right, and Low Frequency Effects (LFE). We put on one of the DTS CDs, using the McCormack digital transport, and . . . nothing! Around and around we went, trying to figure out what was wrong. Finally, in a phone conversation with Brad Miller at 5.1 Marketing, we discovered that digital volume controls on CD transports work fine with regular CDs, but NOT with the DTS bitstream. Any manipulation of the DTS bitstream will result in the decoder not locking in on the signal (probably true for any DTS decoder). So, if you have a transport with a digital volume control, you have to put the CD into play and adjust the volume on the transport controls until the point is reached that the lock light on the Millennium illuminates. This problem did not occur with the Audio Alchemy transport or the Yamaha laserdisc player, because they are not equipped with a digital volume control. The DTS output of both players resulted in immediate lock-on with the Millennium.
The sound of DTS is really stupendous. Like AC-3, DTS gives the listener a true sense of incredible involvement, but, of course, a good part of this depends on the engineering of the recording. All of the DTS albums we listened to had an excellent sound quality, but the musical charm varied widely. Having the lead singer come from the left rear was not particularly appealing, but those sorts of vagaries will disappear as DTS goes from being novel to being routine. In any case, the sound was clean, with no obvious harshness. The thunderstorm album gave the entire system a good workout. Both AC-3 and DTS tend to have powerful subwoofer sound tracks, and this was certainly no exception. It sounded so real, I intend to use the album for meditation! I just wish the recording engineers had placed all the microphones a little farther apart and not so close to the puddle that the rain was pouring into. "Jurassic Park" was, of course, spectacular. The Pro Logic version is good, but 5.1 DTS is wonderful.
Perhaps the most revealing of the DTS CDs is the one that DTS published for demonstration (DTS-CD 96091, which came with the Millennium). When I heard it, I realized how important this new technology is, and that I was completely sold on it. There are numerous tracks on the disc, and my favorites are Track 2, which is a chorale excerpt from Tchaikovsky's 1812 Overture, and Track 5, "A Touch of Surround Madness". Being surrounded by discrete tracks of a huge chorus singing this fantastic piece of music is absolutely phenomenal. I am telling you, "You are DEFINITELY going to want DTS!" Track 5 is the most demanding CD sound I have ever heard. Of course, it is meant to impress the listener, but if the technology could not handle it, the impact would not have come through. It opens with a deep rumble and a sine wave that goes completely around in a circle. Then, everything from Star Trek to Roy Rogers is excerpted in short bursts. The Millennium performed flawlessly. Really superb sound. And, it will get better. We need to remember that this is just the first rung on a very tall ladder of performance potential. Current DTS releases use a compression ratio of about 3:1, which is a lossy (some musical info is "lost") scheme. However, DTS is capable of delivering 5.1 in a lossless bitstream, up to about 96 kHz sampling with 24 bit word length. This is much greater than current regular CDs with two channels at 44.1 kHz and 16 bit word length. We just need the disc space to put it on (perhaps on DVDs down the road). Audiophiles have been searching for that "you are there" sensation ever since the term hi-fi came into existence. Well, we just moved an order of magnitude closer to realizing that dream with DTS, and the Millennium is on the ground floor.
There are sure to be arguments as to the superior format: AC-3 or DTS. Even though AC-3 uses a compression ratio of 11:1 and DTS is 3:1, I could not hear any consistent differences in our preliminary tests, but again, this depends very much on the software, and I reserve comments here until I have heard many more examples, in particular, a number of sound tracks produced in both AC-3 and DTS. Somewhere down the road, there will probably be double blind experiments that indicate listener preferences, and maybe a demo disc made by an independent producer, with the same music in both formats for everyone to play with. Frankly, I like them both to the extent I don't really care which one wins on the newsgroups. Some laserdiscs will be released with AC-3 and some with DTS. DVDs are AC-3 now, with DTS on the horizon. The CDs will probably stick with DTS. DSS Satellite will use AC-3 and DTS, and HDTV will have AC-3, with DTS as an alternative standard. I plan to get them all.
I am really pleased that DTS sounds so good, and that one of the first decoders, the Millennium, performs so well. DTS has a very promising future, and I feel that it is the best thing to happen to CDs since the CD itself. For outboard decoding, the Millennium is an important contribution to this new format, and can be used with any receiver that has 5.1 inputs. Its upgradability (DTS has the ability to decode much higher bit rates than is presently being used on the DTS laserdiscs and CDs), quality of construction, and high performance make it a very competive piece of electronics. Ours joins the reference lab here at Secrets.
John E. Johnson, Jr.
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