Synergy?

[Bruce B]

IMHO, Dartzeel sounds good because of the particular implementation of the 50 ohm standard in their circuits, not because it is 50 ohm. This is a good case of compatibility, and also happily adds synergy on top, otherwise it would be useless, as, AFAIK, they are the only company using it to connect audio equipment. Cousin company Playback manufactures a source component with 50 ohm capability just for them. As is also has other types of outputs it can be used with "normal" equipment.

Too bad DartZeel coudn't have "implemented" it's SE or Balanced connections as well.

 

[rbbert]

Tim, an S/PDIF cable with BNC connectors is most likely true 75 ohm (also assuming that the components at each end of the cable also use BNC jacks).

 

[Phelonious Ponk]

Tim, an S/PDIF cable with BNC connectors is most likely true 75 ohm (also assuming that the components at each end of the cable also use BNC jacks).

SPDIF is just an example,rbbert. I'm really looking for an answer to a somewhat broader question.

Tim

 

[mep]

If the spec for a coax cable is 75 ohm, and if everybody sticks to that I don't need to know what my imedance is, well, this is good, because I'm a user, not a designer, and I don't really even want to know what my impedance is, I just want everybody to stick to the specs so if I plug X output into Y input, it shoud operate properly when I play music, regardless of who made device X and who made device Y. And it really sounds like you're saying that's the way the system works.
Tim

Wow! A dyed in the wool objectivist who doesn’t even want to know what the impedance is for a piece or pieces of his gear. What happened to all of those specs and measurements you proclaim to love?

 

[Phelonious Ponk]

Tim, you're living in Winer's world of perfection - it doesn't exist - the real world isn't perfect.
The fact of the matter is that optimal is 75ohm but most manufacturers don't care about this but are still compatible.
Compatible to me means the two devices will work together.
Optimal is a step above this requirement which I would call adequate.

I've explained it enough now & further questions on your part will simply be semantics. You know what the point is!

I get that...and this particular spec is just an example...75 ohms is a target, a specification, and in an imperfect world there will be some variation on that specification. What I still don't get is, without knowing what the variation is, on a component by component basis, so you can optimize the match, how are you optimizing the compatibility (your semantics, not mine). And I'm not playing with you, John, I really want to know.

Tim

 

[mep]

I get that...and this particular spec is just an example...75 ohms is a target, a specification, and in an imperfect world there will be some variation on that specification. What I still don't get is, without knowing what the variation is, on a component by component basis, so you can optimize the match, how are you optimizing the compatibility (your semantics, not mine). And I'm not playing with you, John, I really want to know.

Tim

But Tim, the specifications and measurements that you have in abundant supply for all of your gear should clearly state what the output and input impedances are.

 

[Gregadd]

A different slant on Synergy
http://www.stereotimes.com/comm0200a.shtml

When a new audio component actually sounds as good in our homes as it did at the dealer's, it's often cause for celebration. However, for most audiophiles, synergy between audio components has been, and still is, more luck than design."

 

[JackD201]

John, Mark,

I don't think Tim is being argumentative (this time just kidding Tim ). He's asking what can be done to improve on that particular situation/example (SPDIF). I'd like to hear a concrete answer too, particularly for DACs that only have SPDIF inputs (the greater majority of consumer DACs).

 

[LL21]

John, Mark,

I don't think Tim is being argumentative (this time just kidding Tim ). He's asking what can be done to improve on that particular situation/example (SPDIF). I'd like to hear a concrete answer too, particularly for DACs that only have SPDIF inputs (the greater majority of consumer DACs).

I am no techie...i know PAD make an RCA adaptor for digital equipment spdif inputs that apparently helps reduce jitter relating to the fact that many RCA jacks are not actually 75ohm...many are closer to 55 i am told. no idea about the science behind this, though i am told better jacks (or bnc) will be closer to the true 75 ohm impedance.
supposedly this adaptor helps 'normalize' this? no idea how. http://www.puristaudiodesign.com/products/accessories/dia.html

 

[KeithR]

Gee, another 100 post WBF thread that is now an objectivist vs. subjectivist battle. I count 7 of these just on the home page.

Just a clarification Tim, which active monitors do you proclaim to be better than synergistic separates w/ normal speakers? Thanks, KeithR

 

[jkeny]

John, Mark,

I don't think Tim is being argumentative (this time just kidding Tim ). He's asking what can be done to improve on that particular situation/example (SPDIF). I'd like to hear a concrete answer too, particularly for DACs that only have SPDIF inputs (the greater majority of consumer DACs).

Well my point was to show the difference between stuff that works together & stuff that works optimally (in this parameter anyway).
So the obvious solution is to know about this impedance & only get equipment & cables that are as close to this characteristic impedance as possible.

So what can we do with stuff that doesn't adhere to the 75ohm? Well, we have to try to deal with the effects of impedance mismatches. The effects are reflections & signal loss. Signal loss is maybe not a big problem as it will likely not cause drop-outs. Reflections are more insidious & do lead to jitter. Please everybody, let's not get into the audibility of jitter If you want to test this audibility in your own system invest $15 as per the following paragraph.

How I deal with it I have said elsewhere on this forum - use an RF attenuator on the SPDIF cable. This seems to have the effect of minimising reflections & lowering jitter. They cost about $15 or so & make a noticeable difference to the sound, taking sharp edges of it & giving a smoother, silkier sound to the highs. See here for what you need to buy http://www.whatsbestforum.com/showt...st-objectivist&p=107878&viewfull=1#post107878

 

[NorthStar]

---Wow, one word from Ethan ('Synergy'), and that's where we are at; ahead with 111 posts! :b

 

[Ronm1]

Should add that on my last round of DAC mods I sent Steve the cables I use to impedance match at the DAC end.
Just another nice touch.

 

[Robh3606]

I get that...and this particular spec is just an example...75 ohms is a target, a specification, and in an imperfect world there will be some variation on that specification.

Look up VSWR especially with a 50 Ohm termination. That is a standard RF termination. It's a measurement that is all about impedance matching.

http://en.wikipedia.org/wiki/Standing_wave_ratio

There is no equivalent that I am aware of at audio frequencies.

Rob

 

[Phelonious Ponk]

Just a clarification Tim, which active monitors do you proclaim to be better than synergistic separates w/ normal speakers? Thanks, KeithR

That's a question that can only begin by asking a couple more questions: Which synergistic separates? Which normal speakers? There is no question that there are good and bad passive systems and active systems, so there are passive systems that will out-perform some actives and vice versa. And there are some very good sounding passive systems. But I do believe that any passive system could be improved by good active design and implementation. The passive crossover is a nest of resistance between the amplifiers and the things they are attempting to control, the drivers. There's nothing good about that, and beyond serving its core function, it seems to me that excellence in passive crossover design is about minimizing the damage.

Tim

 

[jkeny]

I get that...and this particular spec is just an example...75 ohms is a target, a specification, and in an imperfect world there will be some variation on that specification. What I still don't get is, without knowing what the variation is, on a component by component basis, so you can optimize the match, how are you optimizing the compatibility (your semantics, not mine). And I'm not playing with you, John, I really want to know.

Tim

Tim, you are playing.
You asked for examples of optimisation, I gave you a particular one i.e two devices that are manufactured to the 75ohm SPDIF spec are optimised for SPDIF, - simple, easy to understand, what's the problem?

Now you are asking a totally different question - how to change existing mismatched devices into a more optimised configuration! I have given jackD the way I do it but obviously this is still not optimum. SO I guess this answers your question - now go & try one of these RF attenuators on your RCA SPDIF connections & let us know what you hear

The other thing you don't get is in your statement " in an imperfect world there will be some variation on that specification." It's not that manufacturers try to get it right but the tolerances of components drift this from ideal - it's that a lot of manufacturers don't know, don't care or consider it unimportant - "it works after all, doesn't it & I don't hear any difference" type attitude. I'm sure this will strike a chord with you!

 

[JackD201]

I'd try it but my players are stand alone and my only transport/dac combo uses AT&T glass.

 

[Phelonious Ponk]

The other thing you don't get is in your statement " in an imperfect world there will be some variation on that specification." It's not that manufacturers try to get it right but the tolerances of components drift this from ideal - it's that a lot of manufacturers don't know, don't care or consider it unimportant - "it works after all, doesn't it & I don't hear any difference" type attitude. I'm sure this will strike a chord with you!

So they can do it perfectly, they just don't bother because they believe everything works well within a range? In your experience is this sloppiness pretty common or do most manufacturers hit the spec?

Tim

 

[jkeny]

So they can do it perfectly, they just don't bother because they believe everything works well within a range? In your experience is this sloppiness pretty common or do most manufacturers hit the spec?

Tim

As I said already, you can get a measure of this yourself by judging how many SPDIF devices use RCA connectors!!

PS. Have you got RCA SPDIF connectors? Are you going to try the RF attenuator? If you need more info about this, just ask!

EDIT: I also left out an important factor - economics! What you have to ask yourself about any particular manufacturer - the balance between price point and performance point? It might also throw some light on high-end & what the better manufacturers might be about

 

[Phelonious Ponk]

As I said already, you can get a measure of this yourself by judging how many SPDIF devices use RCA connectors!!

Not sure I get what you're saying -- is this primarily or exclusively a problem with SPDIF/RCA devices? I can get an idea of how common the problem is by estimating how common RCA coax interfaces are?

PS. Have you got RCA SPDIF connectors? Are you going to try the RF attenuator? If you need more info about this, just ask!

I did a quick Google of RF attenuators and looked at some products. I see variable, fixed, in different values. I would assume...though guess might be more accurate...that I'd need a 75 ohm fixed attenuator? On the 3 sites I checked, I didn't see any RCA examples, only BNC. But with all of that said, yes, I'd like to try it. A question, though. This is a passive, resistive device, correct? Does it not affect the waveform? Are we sure we're not trading problems?

I'll take your insistence that I'm playing as a compliment, John, but seriously, my technical knowledge is pretty limited. I'm inquiring.

Tim