Super_BQ Posted May 25, 2002 Share Posted May 25, 2002 Can you really compare the sound quality of a DVD player (DTS, Dolby, etc..) to (red-book) CD format? Are consumers confused? Certainly and that's why we have companies selling uttely junk obsolete technologys year after year with NO and repeat NO real improvement in sound quality. We have those MiniDISC (MP2) and MP3 and DSP that have one thing in common - COMPRESSION! When the data is compressed, we lose sound quality. The sad truth is most people can't hear the difference because their equipment isn't good enough. All these new formats and gadgets do nothing to make the job of the recording masterer easier. Recording engineers like Bob Ludwig often complain how the consumer audio market doesn't give the buyers the ability to reproduce sound quality the same way as Ludwig would hear in his studio. Of course people can't have what Ludwig uses right in their homes however, is it asking too much for the consumer audio market to make hifi equipment close to what studio pro-gear offers at a reasonable price? (i'm mean since the invention of the 16bit CD, there really hasn't been much improvement). So the only thing I see on the store shelves on Walmart is electronic equipment soon destined as land fill in 3 - 5 years time. The gap between what the studio offers compared to what consumers are getting isn't getting any closer. From a previous post, the person complained why his 10 year old Denon sounds better than his 2 year old Phillips. The answer is simply because of "Profits". It costs too much money to build good power supply and balanced circuits and good components. When looking at DACs, most of these chips are already configured for "balanced line" operations. However, over 90% of the CD players you see on the shelf do NOT utilize it's balanced output. Reason again is profits - it costs a lot more $$ to build balanced circuits as it can require double the amount of components and cicuitry. But doing so we benefit from CMRR (Common Mode Rejection Ratio) which reject audible nasties like EMI and RFI. The recording studio has been using balanced XLR equipment for years and to this day, I often wonder why it hasn't been implemented in car audio where it's most prone to noise and interference. In fact, looking at the past 10 years in car audio - there has been no real improvement / innovation. Just fancy DSP and sparkly display lights with pop-down faceplates. SACD and DVDA may be promising but ONLY and ONLY if the consumer has good enough components to hear the difference in sound quality. You're not going to benefit from 24 bit recording using a Bose wavebox player. On a previous thread, they mentioned about higher bits and bit rates, etc. I would like to add that DO NOT confuse between bitrates you see on DVD players vs. bit recordings. When we see bitrates on DVD and MP3 formats - we are talking the amount of DATA that is processed due to compression. Bitrates have nothing to do with oversampling to produce the analog waves rather, more to do with the quality of the decoding alogarithm. When looking at a regular CD player, all audio CDs are recorded in 16bits and the datastream coming off it is fixed. That the DAC still has to read in 16bit format (ie. a small dump truck that can load / unload 16 boxes at a time). The 20 bit, MASH, 1bit, etc that you see advertising is ONLY and ONLY the noise shaping of the analog wave which comes after reading the 16bit data stream. So why is it that say a 1bit CD player sounds better than a 20bit one? The answer is when assessing any hifi unit, there are may other factors that affect the sound quality (not the DAC). Overall, it's the design of the circuit, power supply, quality of capacitors and resistors, etc that ALSO affect the sound reproduction quality. ------------------ High-end audio = a way to brainwash you! Quote Link to comment Share on other sites More sharing options...
djk Posted May 26, 2002 Share Posted May 26, 2002 As far as I know data on CDs is eight to fourteen modulation. The CD clocks out an eight bit word, seven data bits plus a polarity sign. Ignoring dither and compression schemes that gives 14 X 6dB = 84 + 1.7dB for the Nyquist sampling theorem = 86dB. Oversampling allows for better anti-aliasing filters. Electronic balanced inputs aren't worth a hoot. 1% resistors only allow a CMRR of 40dB. The twisting of the wire only allows a CMRR of 60dB. Only equipment with transformers can show the promise of balanced operation. And half of this is from the RFI rejected from limited bandwidth, and the other half from galvanic isolation. Good transformers cost so much that not even pro equipment comes with them, the best they do is give you an octal socket with a jumper installed. If you want them you remove the jumper and buy what ever quality you can afford. Good shielded bi-filar Jensen transformers start at about $130 each. I used to buy a certain brand of electronic crossover used that was a huge POS. No one could understand why I wanted them. I made the mistake of pointing out that they had FOUR high quality transformers in them. After that they were kind of hard to find for $50. Quote Link to comment Share on other sites More sharing options...
Super_BQ Posted May 26, 2002 Author Share Posted May 26, 2002 hi djk, Ok I think there's a bit of confusion. quote: As far as I know data on CDs is eight to fourteen modulation. The CD clocks out an eight bit word, seven data bits plus a polarity sign. Ignoring dither and compression schemes that gives 14 X 6dB = 84 + 1.7dB for the Nyquist sampling theorem = 86dB. Today, would you buy a cd player with only 86db S/N ratio? Most "TRUELY" balanced output CD players (where the audio circuits are balanced from end-to-end and not by tacking on some resistor) have S/N ratios in the excess of 100db and that is EASILY done by paralleling DACs. A good example is the Accuphase line of cd players that use 12 - 16 DAC! (6 or 8 per channel). quote: Electronic balanced inputs aren't worth a hoot. 1% resistors only allow a CMRR of 40dB. The twisting of the wire only allows a CMRR of 60dB. I was referring where the audio circuits are wired in a configuration that utilizes CMRR and that is ONLY done when both + & - output signals from the DAC have their own identical paths. Whereas in single ended RCA you just have a + and a ground. (ie. on a balanced configured DAC chip, either one of the + or - leads is grounded (when wired for RCA). But when utilizing both polarities, you can see both each + & - leads will need identical circuits hence, double the components required = more $ to build. I've often wonder why are RCA male jacks have the pointy tip that is + while the outter shell is ground and when you go try to plug the RCA jack in, it's the + lead that connects first causing all sorts of bad sounds IF you plug the jacks in while your stereo gear is on. The components itself and the way the wires are braided have nothing to do with a the CMRR of a balanced circuit. Resistors are just resistors regardless of their % tollerance specs. Just use a good RMS ohm meter and measure the resistor to the exact value. I should also add that to fully benefit from CMRR, all your stereo gear must be balanced (where the audio signal from the CD player to the power amplifer remains unconverted to single ended). quote: Good transformers cost so much that not even pro equipment comes with them,.... Uhm, I think you are referring to "Output transformers" which is entirely a different topic to running balanced circuits. It's nonsense to take a singled ended RCA and run them through a pair of Jensen transformers (converting to Balanced) as the DACs in the CD player (per say) aren't designed for balanced operations. Nevertheless, there is some gain in using these output transformers by isolating the noise cause from interconnects. However, in pro studio gear, there is really NO need to use expensive output transformers because balanced circuits ALREADY do the job of what using isolating transformers are trying to do. I would think that the CMRR of using output/input transformers is more of a band-aid as it only deals with isolating outsite noise between interconnect cables (between stereo components). It doesn't deal with the noise affecting the circuit boards INSIDE the unit itself. ------------------ High-end audio = a way to brainwash you! Quote Link to comment Share on other sites More sharing options...
kenratboy Posted May 26, 2002 Share Posted May 26, 2002 I have talked about this to a lot of people, here is my take of it, it is kind of confusing, though: OK, so we are in the early 90's chilling with our early 90's fads like Pog's and, well, forget it. We have CD players and DVD players are on their way. We are happy, Dolby Digital is also coming. Out of the blue, all these "computers?" start making an appreaence. Gateway 2000, Compaq, Dell, HP, Packard Bell, tell us we will die horrible deaths if we don't buy computers. Soon afterwards, we become computer-internet-techheads. -MiniDisc players: I have a Sony MZR-50 in my safe. I bought in in 1998 because it was too cool not to have. I paid $300 for it before I moved to England. Well, it was fine, but I lost interest. -MP3: THIS IS THE GIANT KILLER. Napster. What more do I have to say. As soon as all of us tech heads could start to download FREE MUSIC from the internet, we couldn't have cared less about CD's, DVD-A, SDCD's, etc. Remember, most people have 56K's and can't download 10MB/minuite songs. It was all about free. MP3 1 - CD 0 -MP3 players: You all know what an MP3 player is. A cheap, no-moving-part box that plays MP3's. This delt another blow to CD/sound quality. MP3 2 - CD 0 -MP3 CD palyers: This is a sub Giant Kliier. Let's see, with my portable CD player, i can have one CD or 10 MP3 CD's worth of music. Well, MP3 3 - CD 0 -Crappy computer speakers/headphones: With MP3's, we listen to them with a portable device or computer. Sound quality doesn't matter there. MP3 4 - CD 0 -Broadband: I have downloaded over 5 GB of stuff in the past two weeks. Doenloading a 650MB CD is cake now. It is possible that people will want the full thing? I doubt it, the masses that is. MP3 5 - CD 0 Thats about all I have to say. Conveinence has won over quality. ------------------ Receiver: Sony STR-DE675 CD player: Sony CDP-CX300 Turntable: Technics SL-J3 with Audio-Technica TR485U Speakers: JBL HLS-610 Subwoofer: JBL 4648A-8 Sub amp: Parts Express 180 watt Center/surrounds: Teac 3-way bookshelfs Yes, it sucks, but better to come. KLIPSCH soon! My computer is better than my stereo! Quote Link to comment Share on other sites More sharing options...
Seb Posted May 26, 2002 Share Posted May 26, 2002 I'm fed up with movie studios releasing "plane" versions of DVDs and then Special Editions with a better sound mix and additional special features a couple months down the road... Almost Famous Black Hawk Down Lord of the Rings STOP STEALING FROM US!!! oh, and they should also drop the prices of CDs... that would put a damper on illegal music copying! ------------------ http://members.fortunecity.com/sebdavid - go laugh at my crappy website/equipment http://www.dvdprofiler.com/mc.asp?alias=Sebdavid - go laugh at my puny little DVD collection Quote Link to comment Share on other sites More sharing options...
kenratboy Posted May 27, 2002 Share Posted May 27, 2002 Seb, if CD's were 10-15 cents per minuite (7-10 US dollars), I would be buying a lot more. It is just at $15-$20, NO WAY! Now, I listen to a lot of techno. I download MP3's of a group, if I like them (some are KRAP!) I buy their CD, mainly because they are small and poor. One group, Autechre, I have bought about 10 of their CD's. Some are double, 75 minuite CD's, which is 2 1/2 hours of music, that is good. With DVD's, I know what you mean. One, they are expensive, bu getting cheaper. At CompUSA, the Harry potter DVD is only $10! Most DVD's I see are under $20. A year ago, all DVD's were $25-$30! In general, I am out to HURT the RIAA and other organizations who want to castorat our computers, not simply limit copy protection. It is my RIGHT (legally) to make MP3's, and when I am prohibited to do so, I will NEVER buy a CD from that record company, EVER! Also, some of the copy protected CD's cannot be played back on soem CD players, and some CD's are GETTING STUCK IN THE NEW iMAC AND NEED TO BE SENT IN FOR REPAIR! What a bunch of crap. ------------------ Receiver: Sony STR-DE675 CD player: Sony CDP-CX300 Turntable: Technics SL-J3 with Audio-Technica TR485U Speakers: JBL HLS-610 Subwoofer: JBL 4648A-8 Sub amp: Parts Express 180 watt Center/surrounds: Teac 3-way bookshelfs Yes, it sucks, but better to come. KLIPSCH soon! My computer is better than my stereo! Quote Link to comment Share on other sites More sharing options...
Super_BQ Posted May 27, 2002 Author Share Posted May 27, 2002 We should all note that the sound quality of copy protected CDs is worse than regular audio CDs. This adds another notch further away where consumers will not be able to experience the sound quality of what the artist is suppose to sound like. Major nightmare for the recording engineer. Soon they will make us pay for each time we play the song. Look at all those rich artists like Madonna. I hope their music dies just like Metallica as they keep crying out for more and more money. ------------------ High-end audio = a way to brainwash you! Quote Link to comment Share on other sites More sharing options...
djk Posted May 27, 2002 Share Posted May 27, 2002 "The components itself and the way the wires are braided have nothing to do with a the CMRR of a balanced circuit. " Too bad you don't understand these things. If you call a wire manufacturer like Belden and talk to an engineer real nice maybe he will take the time to educate you. "Resistors are just resistors regardless of their % tollerance specs. Just use a good RMS ohm meter and measure the resistor to the exact value." Sorry, won't work. Number one, RMS applies to AC measurements, not ohms. Number two, if you match the resistors to 1% the CMRR will be 40dB, if matched to 0.1% the CMRR will be 60dB. To get higher a CMRR requires a trim pot to be adjusted while playing a common mode signal and going for the null. This is for low frequencies only. For good high frequency CMRR a trim capacitor will be required. Even then it will have poor RF rejection. "Today, would you buy a cd player with only 86db S/N ratio? " Seems like somebody is confusing dynamic range wih signal to noise ratio.CDs can have 100dB+ SN/ratio and only 85dB dynamic range. LPs can have a 65dB SN/ratio (based on 47K thermal noise) but still have over 100dB dynamic range (due to noise modulation). That is why I also menioned 'dither' and should have also mentioned emphasis/de-emphasis. "However, in pro studio gear, there is really NO need to use expensive output transformers because balanced circuits ALREADY do the job of what using isolating transformers are trying to do." An active balanced system cannot achive the same performance that a transformer can, especilly with respect to RFI, and offers no galvanic isolation. The best performance/price ratio is to use electronically balanced outputs with transformer balanced inputs. Oh, just to drive you nuts, Belden has an article on wire CMRR that shows how the color of the two conductors comprising the twisted pair affect the CRMM. But I'm sure you won't like hearing that, so let's forget about it, OK? Quote Link to comment Share on other sites More sharing options...
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