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Can you tell a big difference between the optical and analog 5.1 for normal dvd audio. I was planning on getting the OPPO dvd player and using analog 5.1 Thanks

Drew

optical/rca (digital) lets your AVR do the decoding

analog lets your player do the decoding

I believe thats the biggest difference (there are other minor ones).

Hold on there! Do you mean DVD-Audio or audio from a DVD-Video? If you mean DVD-A, then you must use the analog ins to get the uncompressed, multichannel sound. If you use the optical or digital coax, you'll either get stereo or Dolby compressed multichannel.

I have never heard the DVD audio format. However, listening to two channel music is drastically different whith optical/coax vs. analog!!

I set up my player with a digital coax and with the L/R analog connectors. Digital Coax was hooked up to "DVD" on the reciever and the Analog was hooked up to "CD". I simply switched between the two while playing a CD. WOW, the differance was incredible! Louder, and with tighter bass with the coax indeed!! The analog sounds muddy. Most of you probably have done this, but try it if you havent!!

Mike

For movies on Standard DVD, the sound quality should be identical between SPDIF/Coax or analog.

Some/most receivers however do not apply the bass management (redirected bass below crossover settings) to the 5.1 analog inputs. Some do, if they digitally sample in the analog input. This may be why SkiTaos prefers the sound of the bass using the digital input vs. the analog. For systems that do apply bass management on the analog inputs, this shouldn't be a problem.

The difference in sound will depend on the quality of the DAC in the player and the receiver or processor. Some players scimp on the DAC so even compressed multichannel in a receiver may sound better than analog 5.1 or analog CD stereo. It depends.

The Oppo 971 supposedly has better DACs than the 980 but its best to let your ear be the judge when comparing the digital or analog outputs to your particular receiver.

Whatever sounds best to you is the way to go. In theory the component with the highest quality DACs should do the work and sound best. Just trust your ears, as jakeman said.

I'm surprised JohnK has not yet added the usual to this thread full of myth.
Is it my turn to stir a pot again John?

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I'm surprised JohnK has not yet added the usual to this thread full of myth.
Is it my turn to stir a pot again John?

Please elaborate. I have not purchased the OPPO yet. My current set up is a 2ng gen HD DVD player doing the up convert with optical output to my receiver. However my receiver also has 5.1 analog with analog bass management. Thanks

Drew, as Ken pointed out, it isn't entirely clear what you meant by "normal dvd audio". Assuming that you weren't taking about DVD-As, but simply the audio on regular DVDs(if it's something different, specify it), there's no good reason not to use a simple single cable digital connection, either optical or coaxial. There'd be no sound difference between the optical or coaxial cables, or the analog cables for that matter. There's also no need with modern equipment such as you have to be concerned about whether the DVDs in the player or the receiver are used. As Alan, among others, has repeatedly pointed out, DVDs are now a mature technology; small measurable differences between them still exist, but these are well below the audibility threshold. Audibly flawless DVD chips are bought in large quantities by manufacturers for as little as $1 each.

I thought analog was uncompressed therefore will sound better than optical. Maybe that is true with HD DVD audio tracks but not SD DVD. Thanks

No, it's the format that determines whether the audio has been compressed. Standard DVDs use a compressed audio format(which can, however, sound excellent when well-done), both for DD or DTS tracks, and the type of connection can't change that.

Thanks Everyone I will stick with my HD DVD player. Now I need some QS8s to replace my rears and my HT should be complete

Since my Rotel 1098 prepro has higher quality DACs over my denon dvd player, I'm using digital cable between the two.

How do you know which DAC is better? Thanks Drew

Drew, I just noticed that in my first reply I was apparently thinking so much about the DVD question that I used DVD instead of DAC in my following comment. The point is therefore that in modern equipment DACs are all excellent and can't be distinguished by ear; the differences still existing between them are so small that only instruments far more sensitive than our ears can measure them. So, this isn't a valid topic of concern these days.

Well, according to the specs the Rotel pre/pro is cleaner quality over my cheap denon dvd player and the rotel is supposed to have better quality parts. Another reason is that the rotel supports hdcd and therefore I have to use the digital cable to use it, otherwise I'll just have to use regular cd sampler from the denon using analog cables. But to be honest, I really couldn't hear the difference between the two and the toslink cable was cheaper.

The Burr Brown Dacs in the Rotel CD players are one of the best digital to audio converters around. It may not be the only reason those players sound so good but its typical of the high quality parts Rotel uses in all their gear. Its the main reason I sold my old player and picked up the Rotel 1072 CD player. On a high resolution audio system or linear speakers like the Axioms, devices with better DACs come across as more detailed, transparent and with higher resolution.

In fact, because they are at the beginning of the system chain they are very important to performance. Like alot of devices they give off various harmonic and phase distortions which are measurable and as a result different quality DACs have varying audible characteristics. DACs also vary by resampling frequency with the cheapest ones sampling at 16K times and the best ones at 192K times per second. They also vary by the amount of dynamic range they can produce. Other great Dacs are under the Wolfson, Sigma-Delta and Crystal brand names. They all aren't created equally and much research continues in making better Dacs.

Because they aren't all of equal performance on some systems analog outputs will sound better than using digital outputs and vice-versa. Besides letting your ear be the judge it also helps to know what the DACs are inside the devices and their performance characteristics.

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On a high resolution audio system or linear speakers like the Axioms, devices with better DACs come across as more detailed, transparent and with higher resolution.

In fact, because they are at the beginning of the system chain they are very important to performance.

Facts must be validated by 3rd party, blind and indepedent testing.
Until then, it is subjective speculation and not a very good one at that.

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Because they aren't all of equal performance on some systems analog outputs will sound better than using digital outputs and vice-versa. Besides letting your ear be the judge it also helps to know what the DACs are inside the devices and their performance characteristics.

All good myths but thank you for highlighting them yet again for the newbies who are trying to learn facts and not standard salesmen lines that get consumers to buy more expensive and useless products.

For our next trick boys and girls, how to make your system sound better by placing magical bullets on top of the equipment. My cousin's mother's brother's dog's flea heard a difference, so it must be true.
http://www.totemacoustic.eu/english/acc/beak_01.html

I can't belive that someone made those. Amazing.

Maybe that is why so many people have been putting plants and other decorations on their speakers.

I mounted a couple of those Beaks on my dog to help with his parasitic resonances.

This is something I hadnt considered about higher end DAC. It is something I can easily believe in.

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They also vary by the amount of dynamic range they can produce.

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Facts must be validated by 3rd party, blind and indepedent testing.
Until then, it is subjective speculation and not a very good one at that.

I'm not sure what you are referring to but I am surprised to see you dismiss DACs as an important aspect of performance. A simple test of audibility of different DACs is to install a cheap low sampling rate sound card into your computer and then listen on headphones. Next install a high end 128X soundblaster card and listen again . Even my 11 year old can hear the difference. Same reason that DVD-A mastered at 24bit/192khz sampling sounds better than most CDs mastered at 16bit/44.1khz. I presume you have heard the difference between DVD-A and CD? ADCs (Analog to digital converters) were used to create them.

Good DAC design keeps noise/distortion to a minimum, preserves dynamic range, and faithfully converts the digital signal to analog without introducing unwanted artifacts or dropping data. The expertise that goes into creating good from not so good DACs is a specialized area of electrical engineering and research. There are well accepted performance parameters associated with DACchips such as better signal to noise ratio, dynamic range and channel isolation or crosstalk (much like in an amp). Its not a static area much like the design of computer chips continues to advance.

I don't think these remarks are worth dignifying with a response but the DACs used in receiver/processors, dvd and cd players contribute significantly to their ability to reproduce sound accurately. Its not as simple as converting ones and zeros to analog sound but far be it from me to convince you otherwise.

The good news is that like all chips the performance to price ratio keeps improving and the difference are becoming more marginal. Nevertheless not all audio equipment is created equally. Of the various DACs I have heard over the years the Burr Brown PCM 1792 DAC has outstanding specs and for that reason has found its way into many Denons, Rotels and Anthems. But like many audio products diminishing returns set in and no matter how good a DAC may or not be, a system is only as good as its weakest link. There is also a view that a DAC with 20bit resolution and 120db SNR is at the limit of audibility so DACs with much better specs are unnecessary. Like most audio design it comes down to implementation.

Here's a couple of basic articles on DACs but be forewarned its not light reading and more directed at people with physics or engineering inclinations.

http://psbg.emusician.com/ar/emusic_digging_digital_audio/index.htm

http://en.wikipedia.org/wiki/Digital-to-analog_converter

Anyway if you want to believe that a good DAC makes no difference thats fine with me. The purpose of this digression was to encourage people to listen to their digital or analog connections and not assume one is necessarily better than the other. Results will vary with the equipment being used.