JayDee

It depends on where the reflection occurs. That waveform isn't a particularly ugly case; it's just one I happened to have immediately accessible that shows what a reflection looks like. My intent here was simple to illustrate a cable reflection, rather than to show what a really bad digital waveform looks like.

Yes - jitter has a several causes and influences, and one of them is interface jitter. This is the primary reason why digital cables have a sonic signature, though by a different mechanism than those used for analog connections. The parasitic effects are there in both cases, but any timing issues on the analog side would show up as phase shifts that are so small as to be undetectable except in extreme cases. With digital, the timing issues are much more pronounced and consequential. It is unfortunate that the RCA connector has become the de-facto standard simply by winning a popularity contest. I yielded to that influence myself in the sense that the first two generations of Diverter used an RCA connector, but I knew from day one that I didn't like it from a technical point of view. The third gen uses a BNC, but still accommodates those who want to use RCA connections by supplying an adapter.

Sure, thanks for your kind words. FWIW, I expected opposition, and although the experience often feels like running the gauntlet, I welcome the opportunity to articulate my views on the forums. It has been an interesting experiment. I think I've probably posted more than enough for today, so I'm going to sign off for a bit. I'll continue to monitor the thread and will post if there's something that merits comment. Here's looking forward to that cab ride.

Yes, I agree. And that is what will be offered... when they are ready. You're absolutely right about the receiving end having an influence on the jitter measurements. That is why measurements are done under repeatable conditions - in my case, using a 75 ohm cable coaxial, terminated into a SMT 75 ohm, .05% resistor. Most equipment is tested in this repeatable, controlled fashion, although the designer knows full well that the environment will unavoidably alter the performance. On the speaker side of the business, for instance, most speakers would be designed with anechoic or quasi-anechoic measurements, but the room environment in which they are used alters that sort of textbook response in a major way. In the case of a SPDIF interface, I can show you what happens with it is improperly terminated, as I happen to have these measurements handy. The first waveform shows the results from an improperly terminated interface (cable has an incorrect impedance). You can see a reflection (dip) riding on top of the square wave. The second waveform shows the results with correct termination. Incidentally, this is SPDIF output from a current generation Diverter.

All of these concerns are acknowledged, and we're doing all we can to rectify them. I wish I could significantly advance the schedule and have everything in place right now, but it takes time, generally much more than I'd like. At least one formal review is pending, and others are scheduled. The Diverter has already been at some meets, and will be at more in the future. Obviously we'd like to have everyone who has the interest to have an opportunity to try one out, but please realize that each one of these is entirely designed, machined, assembled, and tested by me personally; it is simply not possible to send one out to everyone who might want to play with it casually.

No, not at all - every single Diverter that goes out the door is subjected to both listening and instrumentation tests.

Look, you can float all the theories you like about the real reasons behind my not posting comprehensive Diverter measurements. I have already stated that more will be forthcoming at such time as I am able to prepare them for public consumption. Despite what many here seem to think, this doesn't mean I haven't performed any, or that I don't recognize their value. As it turns out, the equations of running a small business don't quite balance out that way, at least for me. When you start your own audio business, you're free to prioritize your time and resources towards pleasing everyone on the forums. Let me know how that works out for you.

As do I, but the key word here is "possible" - sure, ideally speaking, it would be great to have a copy of every competitive device on the market. But it's hardly practical to do so, and even if it were I would question the value of doing it relative to how those resources might be otherwise employed. As I've already stated, I have measured several others, and I didn't go into this (or any other project) ignorant of my competition. That's just basic R&D. I never claimed that it did. This was a difference test, not an absolute test, designed to show one thing, and one thing only: that the Diverter is, at least as far as the methods of this test allow, transparent in the way it handles digital data. The results of the test would be valid for comparison if and only if the testing device were calibrated to some kind of recognized standard, allowing anyone else with similarly calibrated equipment to repeat the test results with some other device. I wasn't attempting to be nearly that formal or comprehensive in this test.

I'm laughing - that was a good one. One of my favorite movies BTW. If I wanted an opponent (or several) it appears I came to the right place.

It is entirely possible for poorly-designed digital gear to produce significant, even severe, THD and IMD products. For instance, take a look at the differences between an excellent asynchronous sample rate conversion algorithm and a bad one - it isn't subtle. Do you have specific test methodology in mind? And I would love to provide them - but it will have to wait. If I did nothing but run all of the measurements people requested, it would be a full-time job for me.

I have tested one other that I had access to through a friend, but generally speaking I don't find it practical or a wise use of development funds to maintain an inventory of competitive products here for testing. The baseline SPDIF to SPDIF loopback is the frame of reference in this case - the only point of this test was to establish the Diverter's "transparency" if you will, not to compare it to competitive products.

I'm not sure how you distilled that message as the essence of what I wrote. That was certainly not my intent. That makes two of us. Thank you! Those are valid points. But I wasn't claiming to be offering a comprehensive suite of tests with the results I linked to; I was basically trying to throw a bone to the people that kept calling for some kind of testing, and I was also trying to show those who own a Diverter (and are so inclined) that they could run some tests themselves. And at this point (schedule-wise) I'll have to leave it to others to provide comparative test data or blind listening tests. There is also the issue of one manufacturer providing test data for the products of others - I would rather not deliberately pick fights with fellow manufacturers. They would likely be suspicious of my test results, just as I would theirs (unless I knew them well enough to be confident there was no subterfuge going on).

I realized that few here are likely to be satisfied by the content of my first post over at Head-Fi. That's why I included links to both threads. If you read through the second one, I think you'll find that most of the questions or criticisms that have been or are likely to be raised here have already been addressed there - though of course they may not be to everyone's satisfaction. I didn't want to post lengthy, redundant info here when I'd already written it out once.

I see that now - sounds like it was a case of unfortunate timing in that I had begun composing my response before you deleted your post. Sorry about that.

So, bigger = better? Why? If you're speaking from personal audition experience, I certainly respect your opinion. But if not... well, that's a different matter.