Yamaha-DSPA-1-DTS-Article电路原理图.pdf

A lot of manufacturers in the consumer electronics industry do some things right. Some compa- nies have perfected ergonomics, while their products performance suffers. Other times performance is great, but build quality is less impressive. Some really high-end products may perform great, but can break down more often than they actually work. There are, however, a very few products that just might be perfect for anybody. What most manufacturers strive for is the closest approximation of perfection that is allowed by cost, all the while trying to appeal to the widest possible audience, and at the same time maintain a good profi t margin. What we as con- sumers strive for is the best possi- ble future-proof piece of gear for the money, as long as its a good value. Very rarely do these two outlooks collide, except, it seems, for this unit under review. Yamahas newest integrated amplifi er, the highly touted replacement for their amazing DSP-A3090, is the DSP-A1. Its the fi rst of a wave of DTS products from Yamaha, which will include single- and multiple-disc DVD players, perhaps by the time you read this. Of course, it wouldnt make any sense to offer just a DTS source machine in the line, so Yamaha went full throttle and came out with a DTS integrated amp. Now, some of you may be wondering from the photo on this page why Im referring to the D S P -A1 as a receiver, and not simply as an integrated amplifi er. Well, dear friend and astute reader, the main difference really is the absence of a tuner, which magically transforms a receiver into an integrated amp. Thats it. As my psychotic family doctor used to say to me as a child after stabbing some 12-inch needle in my wimpy, wiry arm, “Its as simple as pie.” Outfi tted with chips to handle Dolby Digital, DTS, and Dolby Pro Logic, this baby is set for the future. With powerful internal amplifi cation that (at least on paper) would put many external multichannel amplifiers to shame, we were really excited to fi nally get Yamahas latest into our listening room. As far as features go, this unit has it all. First and foremost, as mentioned above, its capable of processing all the major software formats, including DTS, Dolby Digital, and Pro Logic, and it does so with high-quality 24-bit analog- to-digital converters, as well as 2 4 - b i t digital-to-analog converters. T H E A T E R T W O Yamaha DSP-A1 DTS/D olby Digi t a l I n t egrated Am plifi e r Could this be the perfect integrated amp? Read on to fi nd out. by Jeff Cherun Home Theater/ July 1998 A A. Practically future- proof, the DSP-A1 was a hit with Jeff. B . Jeffs anti-vinyl bias aside, some consumers may fi n d the phono input useful. B RadioFans.CN 收音机爱 好者资料库 It also delivers the goods on inputs and outputs. The DSP-A1 has fi ve S-video inputs and four S-video outputs, duplicated in the composite domain with the usual yellow RCA jacks weve come to know all too well. Those of you with a laserdisc player will be pleased to know that Yamaha has thoughtfully included a built-in RF demodulator, so you can just plug your Dolby Digital RF output right up to the RF input on the hindside of this beast. In the standard digital domain, there are also a plethora of connec- tors, including three coaxial digital inputs, as well as fi ve optical digital inputs and one optical digital output for recording onto a Mini- Disc, DAT, or CD-R, for example. Another esoteric feature Yamahas thrown in thats normally left out these days is the phono input for hooking up your (or your Dads) turntable. As a hater of all things vinyl, Id never use it, but its there if you want it. The binding posts on the posterior of the DSP-A1 are the kind we love to see here at Home Theaterbeefy and fi ve-way. Now some manufacturers give good binding posts for the main and center channels, but skimp on the rears. Again, Yamaha has taken the high road by giving us a full complement of fi ve-ways. Also, if you decide the internal amps dont give you enough juice, and you want to bypass them entirely to external amplifi cation, Yamahas thrown in pre out/main in jacks. One weird-yet-nice addition is the benefi t of a six-channel analog input on the back panel, presumably for some other surround sound format that hasnt yet been released, as the DSP-A1s already got all the current formats inside anyway. In any case, its nice of the folks at Yamaha to have thought of that, and we dont need to use it if we dont want to. Topping it all off are three AC out- lets (two switched and one unswitched) that can supply power to other hardware in your rig. Yamaha, the lone wolf when it comes to 7.1 audio on integrated amps, has continued a tradition that it started with its earlier inte- grated amps. It includes an extra two effects channels for the front part of your home theater. These two limited-bandwidth channels are designed to sit up high above your main channels and complement the sound with added ambient infor- mation. While this information is not strictly embedded in the 5.1 (Dolby Digital or DTS) signals that we all know and love, Yamaha is able to add some good stuff to the presentation through DSPs. I remember a few years ago when I was staying in L.A. for a few days with my buddy and fellow Curt- Conian Brent Butterworth, and we were pontifi cating about this very subject. At that time neither of us had actually heard the DSP-A3090s seven-channel confi guration yet, and Brent was about to hear a demo at Yamahas Southern Cali- fornia headquarters. Needless to say, we were both dubious about the whole deal and wondered if it was a gimmick. But when he got back, he claimed it actually made the home theater experience better. Normally Im a pessimist when it comes to gimmicks, but when I heard the test sample a few weeks later, I agreed. Lots of times manufacturers give us answers to questions that nobodys asked. This time some- one was actually thinking and turned an excellent idea into something more. The DSP-A1s manual is among the fi nest available in the con- sumer electronics industry. It gives explanations of what is going on in the machine and gives elaborate descriptions of different setup scenarios. My kudos to Yamaha for putting the effort into explaining such a complexly featured unit. Setting up the DSP-A1 was fairly simple, and once all the connec- TESTING SYSTEM Vienna Acoustics Speaker System Defi nitive Technology ProCin- ema Speaker System M the low-pass fi lter measures 24 dB/octave. Crosstalk from analog inputs is -72.0 dB at 1 kHz. A-weighted signal- to-noise ratio from analog inputs is -77.7 dB; from digital inputs, it is -82.7 dB. Dolby Digital frequency response is virtually identical for all channels: +0.13/-0.35 dB from 20 Hz to 20 kHz. These are all good to excellent mea- surements. Yamaha DSP-A1 Yamaha DSP-A1 DTS/Dolby Digital Integrated Amplifi er$2,799 in black$2,599 Yamaha 6660 Orangethorpe Ave. Buena Park, CA 90620 (714) 522-9105 Integrated amplifi er decodes DTS, Dolby Digital, and Dolby Pro Logic Seven channels of amplifi er power, including fi ve channels by 110 watts Champagne fi nish is a true beauty to gaze upon H I G H L I G H T S Reprinted with permission of CurtCo Freedom Group. For subscription information, please call 800-264-9872.