Bevan,

You are absolutely beautiful. You just managed to emphasize my points regarding coaxial vs. optical in the past couple of days. The whole argument was "digital" transmission ("1" & "0"), not "analog" transmission (varying voltage levels). My point is that coaxial AND optical do perform ("digital" transmission) similar FOR THE TASK AT HAND, and that's DVD-AUDIO. Thus, any external interference must be "large" enough for the data stream to lose bits ("1" and "0"). If the external interference is causing some bits to "lower" (voltage level wise) a little bit that's fine!. AS LONG AS THE BITS DON'T CHANGE STATE!!!.

Regarding your question:
1. All metal oxidize to some extend, depending on their characteristic.

* If the connection is somewhat "permanent" (you are NOT going to unplug it and replug it from time to time), then any type of connector is fine (tin, silver, gold). Because the oxidation will happen on the outside of the connector, not at the point of physical contact. Thus, cosmetically it looks bad, but it still works.

* If you are going to plug and unplug the cable very often, then I suggest gold plated. Gold plating reduces oxidation of the connector, creating good contact. Of course you're not going to plug and unplug it so much that the gold strip off like that on a watch, right?. Oh, by the way, SILVER IS NOT AN ALLOY, IT IS AN ELEMENT, PERIODIC NUMBER 47, SYMBOL AG, IN THE TRANSITION METAL GROUP.

2. You know, the first network that I setup was on a Thin Ethernet. Yet I totally forgot that those still existed (I got wooed by 10BASE-T). Sorry. Again, the transmission is "digital", and the bandwidth of the cable exceed the transmission rate (10Mbit), so the cable worked fine. Since you know about networking, would you use 100MBit cable (Fast Ethernet) in a standard Ethernet network?. You can but NO performance increase. Again emphasize my point, you can use coaxial over optical to transfer DVD-Audio, but will you have ANY performance increase?. Apparently someone thinks so...

AS AN EXAMPLE, TAKE A LOOK AT THE BACK OF A RECEIVER, IT WILL PROBABLY HAS THE FOLLOWING CONNECTORS:

CD In: Probably plugged.
DVD In: Coaxial or Optical. Probably plugged.
Video 1: Probably plugged to connect VCR
Video 2: Probably plugged to connect LD
Video 3: NOT PLUGGED.
Phono: Unless you have phono, NOT PLUGGED.

The point of this exercise here is that if it's PLUGGED, then it is PROTECTED from oxidation. Any oxidation will happen on the outside of the connector only, not inside. If it's UNPLUGGED, unless it's GOLD/SILVER plated, it's going to oxidize. And when you decide to buy an equipment to plug into that connector, it's not going have as good a contact.

My point stands firm. I believe that for DVD-Audio application, coaxial and optical perform comparatively. AND OPTICAL IS A CHEAPER SOLUTION. It is cheaper because at the output stage you don't have to have a driver capable of driving fixed and varying impedance (75Ohm +/- 2). Those are very expensive driver. Instead, just get an off-the-shelf driver and put in an optical converter instead. For now, most vendor still have coaxial output, with the optical output tapping from the coaxial output.

So the moral is: Know what you buy, don't overspend on something that's not going to give you any performance increase. Save that money to buy better equipments, or better controls, like Pronto!...

Bevan,
To reiterate my point,
Its not JUST the connection at the receiver or source, its the connection of the Gold to the substrate metal on the connector.
Fiber optic in my home environment suffers little from external problems.
As far as music is concerned, it has a variable amount of data, and the processor at any point can be challenged to reproduce fidrlity. The processor interpolates ( Kinda ) values beyond 16 bit resolution. COmputer data is packed ( unless compressed) in a constant manor( aside from any other packing software). Music is bandwidth variable. Different beasts. DVD id the same. Look at a DVPS 7000 display. It can go from less then 1 mbs to 10mbs.

Daniel,

Gee, thanks! How did you know I am beautiful? Women usually just call me 'handsome' and I fall off the chair already! :-D

Looking back at your earlier posts, you did have a mention on digital vs coax: "The DAC in most DVD players are either 20-bit or 24-bit type, which poses no threat to either coax or optical transmission. Both are shielded sufficiently and are short enough that there must be major interference in order for the transmission to have a bit-error." I guess that line was probably glossed over and the argument just shifted to "coax vs optical" instead of "coax digital vs optical digital".

Anyway, I'm getting the hang on this optical and coaxial thingy now...Wish I'd thought of the '1's and '0's logic when I was buying my cables...But by chance I ended up buying the cheaper solution anyway! ($50 for an optical cable that is probably plastic as oppose to $35 for a good coax at cost plus labour to make it up...plus I know it's more sturdy!) But now I know I also won't feel bad if an equipment only has a coax digital out but not a optical digital out (though highly unlikely).

By the way, I had my DVD player playing a music CD. The output is digital output. The sound (being interpreted by my receiver) is not as good as the DAC in my Marantz player. So though my CD player has a digital output jack, I don't use it.

Yes, you can use a cat 5 cable on your 10Mbps network...but if you're going to spend the money on cat 5 cables, you might as well upgrade! :-) I have a thin Ethernet network at home, installed many years ago...With all these 100MBps technology, I first thought about upgrading...but then, I only 4 users max on my network, and I didn't think the performance improvement is really going to be THAT great on my really *large* 4-user max network...so I save my money...on DVDs...and the PRONTO! :-D

HiFiGuy,

Yes, MPEG3 uses compression. But I think the compression is on the delta of the next frame to the current frame. (For those who are reading and wondering what delta means, it's the difference between the two frames in this case.)

I think that compression algorithm also contributes to the varying transfer rate that you see on the display.

I'm sure fibre optic in your home environment suffers from little interference, just as coax would. When I first had cable installed, I complained that the picture is not clear and sharp. The cable company technicians (a few of them came down) said that it's my computer network causing it, that it's the area I'm in, that my flat-ribbon TV antenna cable is causing it...None of that is true. The truth: they have a faulty part installed on the connection out on the street!

Computer networks using T-pieces don't use gold-plated t-pieces. And data is not corrupted.

Take modems for example. You can use the best cables for your best modem, or you can use cheap cables for your cheapest modem. If your telephone is noisy, nothing is going to stop you from getting a bad transmission.

Bevan,

It's really interesting that your DVD player when playing music CD would be different from that of a standard CD player. You mentioned the DAC in your Marantz player, so the output goint to the receiver must be analog then. The only possible explaination which I can come up with is "Sound Fields". Does your Marantz CD player has settings for various sound fields? (jazz, pop, rock...). Sound fields uses DSP to process the sound digitally, altering it to suite one's taste. If the sound fields are turned off, then the music should sound as it was originally intended. In that case (with sound fields turned off), it would sound the same between a standard CD player and a DVD player. Because the data on the CD is the same, the chances that you're losing data (bits) is very rare... To truly compare, you must turn off all "special" features on your CD player, such as "Bass Boost", "Simulated Surround"...

Regarding 20-bit, 24-bit... Here's the scoop. Music CD is 16-bit only, sampled at 44.1KHz. Originally some player boost the bit count (in the player) to 18-bit, or 20-bit. However, at the time that the data ultimately reached the DAC (in the beginning there's no digital output), it got sampled down to 16-bit. What's the extra bit for?. Error-correction. That's it. You might have heard some other statements (higher fidelity, better sound...), none of it is true. Remember, the original data is 16-bit, so you can't do better than 16-bit. In the beginning some CD was not very well-made, so reading error was common, thus error-correction makes sense. Now most CD player are 1-bit, very high sample rate. Simple concept, instead of doing it in parallel, do it in serial, do it faster.

The 20-bit and 24-bit in DVD player has to do with the video data, not the audio data.

Your point on networking is very well-taken. I'm thinking of setting up my own home network as well, although starting from scratch I'm leaning toward 100MBit. Either that or wireless. Heck, it costs more, performance isn't that good, but no wiring...

Daniel,

To clarify, my DVD was sending the output through my coax digital out to my Yamaha receiver, while my Marantz is sending the analogue output through normal 'stereo' cables to the Yamaha receiver.

So, the DVD signals has to be decoded thru Yamaha's DAC, while the Marantz is going through Marantz's DAC. That's where the difference in sound comes from. I also test them with DSP switched off. I have also since hook up analogue output for the DVD (for those annoying Australian MPEG 5.1 DVD sountracks), so one of these days, I might try playing the CD from the DVD player and see if it sounds better coming from the analogue output (since this will test the DVD's DAC).

I agree that if you're starting from scratch, you should go for 100MBps with cat 5 cables or wireless, though both options are expensive. I've seen some very impressive wireless stuff from IBM, but the price didn't agree with me. Thing I don't like about cat 5 is that I need a hub and if I want to add more nodes (say, next to the existing machine), I can't just plug a t-piece somewhere along the cable route. But in the long run, 100Mbps is the way to go.

Bevan,

Yeah... I kinda figured that's the configuration.

MARANTZ CD -> Analog Connection -> Yamaha Digitization -> Yamaha DSP Effects -> Yamaha Low-Pass Filter -> Yamaha PreAmp stage -> Yamaha Amp Stage -> Output...

DVD PLAYER -> Digital Connection -> Yamaha Optical Decoder -> Yamaha Low-Pass Filter -> Yamaha Digitization -> Yamaha DSP Effects -> Yamaha Low-Pass Filter -> Yamaha PreAmp Stage -> Yamaha Amp Stage -> Output...

Let's do some analysis. An analog input would requires only 1 Low-Pass Filter stage, after the DSP Sound Field Effects, to smooth out the stair-case effect before going to the amp stage. But optical would requires a lot more filtering, unless the digital signal is fed directly into the DSP (an unlikely event), so it must be filtered twice before getting to the output. The output filter is the same, so the culprit must be at the input end.

From the time of DSP digitization on, all inputs share a common denominator, therefore, the difference must be before that stage. I would think that the optical decoder or the input low-pass filter is at fault if you are hearing differences between optical and analog.

Regarding the network, as mentioned earlier I'm leaning toward 100Mbit as it's more expandable. A number of wireless technologies which I looked at limits itself at some point, either speed or nodes.

BTW, you should be able to connect another hub (say a small 4-port) next to an existing machine and get it on the network. A side question, how are you connected to the net right now? I mean internet. ISDN?. Modem...?

Daniel,

Gee, this is getting technical. I would have thought ultimately, it comes down to Yamaha's DAC versus Marantz's DAC, to making a difference in the sound? In one case, the digital data is being converted to analogue in Marantz's DAC, in the other, it's being converted to analogue in Yamaha's DAC. I would expect that if my DVD player has a 5.1 output and my receiver has a 5.1 input, then depending on the quality of the DAC, I would still hear differences when listening to the 5.1 output decoded by the DVD's DAC as oppose to that decoded by the receiver's DAC?

Anyway, the differences I'm talking about are things like the bass (cello part) sounds softer (almost cannot hear it) when played from the DVD, decoded by Yamaha, and sounded louder (more normal) when played from the Marantz. The Marantz has a very good reputation for its CD's DAC, so I 'trust' its output more. The Yamaha has a full spec AC-3 DAC, and I have no problem with its DAC doing AC-3 soundtracks, but when it comes to music CD, I think it must somehow being decoded through a different circuit (since it's not AC-3) maybe, so it's not as good.

To your side question: I'm connected to the net from work, which is either a T1 or ISDN line (I don't care, as long as it's fast! :-D). At home, I am connected to the net via modems. I have a server that fetches the mail every few hours automatically, and notifies me when there's new mail. If I want to surf the web, then I logon manually.

As for the hub, of course you can. I had a temporary lapse of memory. Although, a small hub is still not as cheap as a t-piece. But I'm sure that won't be a problem in a few years time. Another potential hassle is the making of cat 5 cables. I saw it at PC shows where they give demos on how to make these things...one mistake and you'll have to start all over again. Go wireless! (and have the Pronto control your network) :-)

The creation of a cat 5 cable in the 568B or USOC pin configuration is relatively simple if you have a crimper. Goto your hardware store and pick up the crimper and refer to the wiring configuration you need.The female jacks are color coded. The female recepatcle is as easy as laying the wires into the respective trackes and pushing them in with a small screw driver. The male end is a little more difficult. Strip the wire back a bit, straighten out the 8 conductors, arrange them into the pattern you need and hold them around 3/4 of an inch back. trim the end so it is even. Slide them into the male jace. Crimp. Make sure you know whether you need a crossover cable or a stright through cable. Crossover from modem to hub, Straight through from hub to ethernet adaptors.
As for the DAC issue, It is important to note is you are using your system in the high pass filter mode. This is actually not as easy as it sounds since alot of receivers dont do the filter thing consistantly. Denon receivers dont have a subwoofer out on the base. Yamaha wont high pass on the 5.1 input. Sony doesnt have a sub out in the Stereo mode unless its in the accoustic setting. Generally speaking, Its difficult to do an AB of receiver versus CD if the high pass filters dont engage. I have a multitude of scope tests on a variety of receivers to confirm this. Even polarity of the terminals have been found to be backwards. Youd think if you spend a grand or better, they could get that right! As a side note, I have a technical sheet from Enlightened Audio Design that was sent to me from engineerng at my request for this thread. I will post in a new thread on Tuesday . It also adress 96/24 audo and SACD.

Bevan,

Yup, I kinda expected this. Any sound differences you hear must be in the low frequency area. The culprit must then be the input stage low-pass filter. This input filter is not a low-pass, rather it's a bandpass filter (filtering out anything above 20KHz and below 20Hz, according to the spec of the receiver. The analog input from the Marantz does not go through this input filter, thus the bass below 20Hz must be getting through. The fundamental frequency of the Cello is around 250Hz though, so that must have gone through (not filtered). The bandpass filter probably aren't doing a good job at low-frequency. It must have "rolled-off" (filtering) too quickly at the low end.

Anyway, you're right. It's getting way too technical. Let's talk Pronto instead. I'm thinking of connecting my PC to my Home Theater system, but with my PC in another room. So how about this:

Pronto CCF displaying a keyboard -> IR Receiver -> IR Transmitter in another room -> PC -> Display information to a RF transmitter -> RF Receiver -> TV.

The RF Receiver/Transmitter would be something like the DVD Anywhere that's advertised at X10. The IF send from Pronto would be from a cordless IR keyboard. I wonder if the Pronto can learn the IR from a cordless keyboard???... This post should really be in the Pronto forum, but since you're the Pronto expert, I figured I ask you anyway...

Daniel N.

In your June 9th post you wrote:

"Jitter. This has to do with optical advantage #3. Coaxial has this complete braided shielding from one end to the other, while optical has none. Then how does the signal ground of the equipment 1
got connected to the signal ground of equipment 2 (that's what shielding does)?. It doesn't. So therefore there always will be a little bit of signal offset between the equipment, simply because the ground planes of each equipment is at a different potential (voltage). Trust me, the ground plane (unlike its name) does not stay at 0.000Volts."

Ground plane differences and ground loop issues are only a problem in the case of coax connections which share an electrical signal between the two devices. This is not an issue with optical connections, there are no problematic offsets in light levels(dark is always dark) between the two devices. In fact, the opto-isolation provided is desireable to prevent ground loops.

That said, I'm still not pushing Toslink. Overall, the preferences seem to lean towards coax from what I've seen and heard.

Daniel,

I'm not a Pronto expert...Vanee is much more qualified...he was in the development team...I'm in the 'Consumer:-hey-where-is-the-ProntoEdit-update' team. :-)

IR keyboards is not a problem for Prontos, I've read it somewhere that somebody has tried it and it works. I believe Daniel Tonks even has a keyboard layout CCF that you can download. Barry Gordon uses his PC to control his home theatre, you might want to pick his brain on setting up yours.

:-)

Daniel,

We are in the process of installing a pronto controlled AV/PC system. Basically, the Pronto is given simple navigational commands much like a web tv keyboard in terms of direction a nd functions. An IR pickup is placed in the desired rooms. nA NTSC card is placed on the host PC and the PC video is sent throughout the house on a modulated signal. Video is switched through a home audio AV controler that is RS232 capable which also recieves the IR commmands. It talks to the PC that contains all of your IR codes and controls to operate your system. The complexity of the Pronto is reduced to NIL because the majority of the controls are in the PC. Also the number of items and graphics are greatly expanded. All that is needed is a video monitor in each room to view the PC control program and to show any other Video on the input. Where there is no video, use a keypad. System status is tougher to do, but if your interested, there is a CCF for the CD controller that uses Sony S link protocol so there is no guessing as to what the CD is doing.

Bevan, HiFiGuy,

Thanks for the input regarding a Pronto controlled Entertainment / PC system. The info. that I got from both of you seems to be exactly what I had in mind. The idea is to have Pronto control everything, both the AV and the PC. The wireless IR keyboard will only be used during "major" PC operation, with the Pronto capable of doing "basic" PC operation.

It all comes down to can the Pronto learn the IR from a wireless keyboard?... I think I need to talk to Barry Gordon...

Thank you very much guys for the tip...

DougW,

The jitter associated with optical transmission has to do with the instability of the signal across the time-domain, not the jitter that commonly thought of as "noise" riding along with the signal.