[manaox2]

Try thinking about why reflections occur in an electrical signal (irregardless of digital or analog, they are both electrical. hint: Ohms law) and why a reflection having a longer distance to travel would create larger differences in timing which is the basis of jitter. If the impedance were perfectly matched, you wouldn't have reflections from what I understand. Longer cables also change impedance with the added conductor and decrease the speed of the signal and the reflections. I'm not sure that this will help or sure I completely understand myself, but sometimes I have to decide whats worth my time researching more into.

If someone did want to research more of course, they can continue trying learning and researching on your own, but that is a greater task as its not specific to your questions much of the time. You have to understand so many basics before you can understand something more advanced and I mean actually understanding something so that you know its effects. If someone wants to have a professional teach them directly about a topic, there are schools and educational courses on these topics and more. Just be aware, they do not have to agree and you have absolutely no real reason whatsoever to be upset at them if they do not. Its not a god given right.

 

[mmerrill99]

Again, seen as you are all alowed to post here without being told to shut up, I will also post & expect the same courtesy to be shown.

Anybody, including Dan Lavry, who purports to give an explanation of how SPDIF or any high-speed signal operates in a cable & leaves out reflective coefficient as part of the explanation either doesn't know about it or is willfully mis-informing, for whatever reason. It is such a fundamental concept & issue that it is a travesty & down right wrong to exclude it. What he said about more reflections happening on a shorter cable, is mis-information as a result of leaving this RC out.

As he would say, it's not about whose opinion I believe but about facts - he was the one who hammered this statement & yet he leaves out one of the most important facts!!!

Please make up your own minds & stop following

 

[DarKu]

...

 

[tosehee]

 

[slim.a]

Should I rename the thread to "jkeny's facts on digital cables" and start a new thread about usb to spdif converters ?

 

[rosgr63]

Quote:

Originally Posted by slim.a /img/forum/go_quote.gif Should I rename the thread to "jkeny's facts on digital cables" and start a new thread about usb to spdif converters ?

Please do!

 

[tosehee]

DELETED for sanity of this thread.

 

[mmerrill99]

Quote:

Originally Posted by slim.a /img/forum/go_quote.gif Should I rename the thread to "jkeny's facts on digital cables" and start a new thread about usb to spdif converters ?

No but I do believe you should realise that you weren't being told the whole picture by Lavry so his self-proclaimed "facts" are missing some "facts" - it's just science, you know! Also, I was not the one who attacked & started this - he attacked me & what I said. I notice that he ducked out when Reflective Coefficient was mentioned. Choose to ignore all of this if you want - I'm finished here unless I have to defend myself again.

 

[nick_charles]

Quote:

Originally Posted by jkeny /img/forum/go_quote.gif No but I do believe you should realise that you weren't being told the whole picture by Lavry so his self-proclaimed "facts" are missing some "facts" - it's just science, you know! Also, I was not the one who attacked & started this - he attacked me & what I said. I notice that he ducked out when Reflective Coefficient was mentioned. Choose to ignore all of this if you want - I'm finished here unless I have to defend myself again.

Reflection (not reflective) coefficient is rolled up into the overall mismatch loss that Mr Lavry has been talking about, if you know the magnitude of the reflections there is no point going into reflection coefficient as you do not need it, its like finding out the names of the electrons in your circuit

and in any case this coefficient is just a loss ratio anyway not some property of the materials, it may be caused by things like terminations i.e changes in material.

 

[Dan Lavry]

Quote:

Originally Posted by nick_charles /img/forum/go_quote.gif Reflection (not reflective) coefficient is rolled up into the overall mismatch loss that Mr Lavry has been talking about, if you know the magnitude of the reflections there is no point going into reflection coefficient as you do not need it, its like finding out the names of the electrons in your circuit and in any case this coefficient is just a loss ratio anyway not some property of the materials, it may be caused by things like terminations i.e changes in material.

Reflective coefficient? There is no such a thing, unless one wants to interchange the wording of reflection and reflective. It stated out as some BS about minimum length of cables, and now we have a new nonsense.

There is real technical knowhow based on real physics, and then there is all that made up nonsense. You will not find any credible literature or any real professional designer that takes such nonsesne seriously. A designer needs to relay on real facts, and designing to the tune of such nonsense is going to lead to gear that does not work.

Cables are about materials and mechanical construction. The electrical issues are distributed capacitance, inductance and resistance. It is the capacitance and inductance that make up the cable impedance. At very high frequencies and long distance, there is also skin effect. Then the signal itself plays a role in what happens. To understand it all, one has to undersatnd elcto magnetic principles, which is at the bottom of all of electronics (the Maxwell equations describing the laws of physics).

Reflections are not about attenuation. If you send a step into an open cable, you will have the signal DOUBLE at the cable end for the period of a round trip. If the termination is higher then the cable impedance the signal reflection ADDS to the step. If the termination is lower, the reflection will subtract from the step.

Any real designer will deal with reflection the way I explained it. Beware - the rest of it is just garbage made up to convince folks to buy stuff.

Regards
Dan Lavry

 

[Dan Lavry]

Quote:

Originally Posted by slim.a /img/forum/go_quote.gif Dan Lavry, Thanks for the time you have taken to post in this thread. By the way, is Lavry Engineering planning to release a usb to spdif converter ? I saw in your website that some of your DACs have usb inputs but there doesn't seem to be stand alone usb to spdif converters. It would be nice anyway if a "pro" company such as Lavry, Lynx or Prism Sound released such a product.

Hi again,

I have one DA that accepts USB, and it is the DA11. The same DA also accepts XLR and RCA connections as well as an optical.

I put it all in one package. Why would you want to have a separate USB to spdif?

I put a lot of features together into a DA...... I do not want to break it into separate blocks.

Regards
Dan Lavry

 

[rosgr63]

Dan you are a fine gentleman, you make great products, and you have my utmost respect.
You know a lot more than all us participating in this thread put together.
I think some people are saying things that may not be accurate.
Please ignore them as I feel you are wasting your time.
Thanks a lot!

 

[slim.a]

Quote:

Originally Posted by Dan Lavry /img/forum/go_quote.gif Hi again, I have one DA that accepts USB, and it is the DA11. The same DA also accepts XLR and RCA connections as well as an optical. I put it all in one package. Why would you want to have a separate USB to spdif? The DA11 offers more features, such as the PIC (playback input control) allowing adjusting the stereo image width, as well as XLR outputs in balanced or unbalanced configuration (user settable), and a headphone output. It has a precision digitally controlled ANALOG volume setting (in 1dB steps), it is remote control reay (for universal remote controls) and much more. The unit is very robust, and the package is small. I put a lot of features together into a DA that out performs units costing 10 times as much. Some of the high level performance has to do with the INTEGRATION of the various features into one unit. I do not want to break it into separate blocks. Regards Dan Lavry

I inquired about a separate usb to spdif converters because there might people (like me) who love the sonic signature of their DACs (even if it is not the most transparent) but are looking for a better transport using their computer, and I tought that a company like yours would make competitive products in that segment.

While I understand that integrating everything in one box would be optimal, there are separate usb to spdif converters popping out every day (bel canto, musiland, Stello, wavelengthaudio ...) and I believe that a "pro" company could make a cost effective no-nonsense product in that segment of audio gear that many people would be intersted in. This is just my point of view on the subject

 

[reverendo]

Quote:

Originally Posted by slim.a /img/forum/go_quote.gif I inquired about a separate usb to spdif converters because there might people (like me) who love the sonic signature of their DACs (even if it is not the most transparent) but are looking for a better transport using their computer, and I tought that a company like yours would make competitive products in that segment. While I understand that integrating everything in one box would be optimal, there are separate usb to spdif converters popping out every day (bel canto, musiland, Stello, wavelengthaudio ...) and I believe that a "pro" company could make a cost effective no-nonsense product in that segment of audio gear that many people would be intersted in. This is just my point of view on the subject

I second slim.a's remark. something similar to the off-ramp sector, but in a better price range would be fantastic! of course I'm being very ego-centrical in asking for something like this, because I'd love to have other options for usb>I2S converters, but I do understand that it would be niche market.
just my 2 cents
best regards
André

 

[tosehee]

Quote:

Originally Posted by slim.a /img/forum/go_quote.gif I inquired about a separate usb to spdif converters because there might people (like me) who love the sonic signature of their DACs (even if it is not the most transparent) but are looking for a better transport using their computer, and I tought that a company like yours would make competitive products in that segment. While I understand that integrating everything in one box would be optimal, there are separate usb to spdif converters popping out every day (bel canto, musiland, Stello, wavelengthaudio ...) and I believe that a "pro" company could make a cost effective no-nonsense product in that segment of audio gear that many people would be intersted in. This is just my point of view on the subject

Many people share this view. If not, this thread wouldn't exist in the first place.

As for the integrated vs. non, I like the simplistic approach. I actually don't mind selling my DAC + Transport and get something like Dan's DA11 if the performance is similar.

I lose the money in transaction, but in return, I get a simple solution which I tend to favor in long run. With my setup, I currently have..

Hiface -> 18' BNC cable -> Ref1 -> Amp -> Headphone.

I'd like to reduce Hiface + 18' BNC Cable, if I can simply plug in USB cable to DA11, and have same or better performance.

That's just me though.

Regards