Exploring Visual Analyser (VA)

I've been exploring the 2012 Beta version of Visual Analyser (VA), freely available at Visual Analyser 2011 XE. It has some extraordinary features, but also a quite unusual approach. It would certainly be helpful to have a manual, tutorial or help notes while exploring. The author, Alfredo Accattatis, invites readers to contribute what he's calling Democratic Help. I've tried to contact Alfredo twice to offer my involvement, but no response so far (maybe he's on holidays!).

It occurred to me that at least some members of this forum might be interested in working together on developing the help, for all our benefit. For example, if one of us picked a topic and put together a tutorial on it, we could all try it out, throwing up objections and queries, and thrashing them out until we lost interest and declared it good enough. Then move on to the next topic until we have the thing at our mercy.

I'd be happy to kick off the first instalment, which logically would probably be on getting it working and initial exploration, unless someone else would like to do that one. I'd probably then move on to Calibration and THD, which I've already had success with.

Any interest?

Terry
 
Maybe.

I see the author of the software has three .rtf files already available, and gives an example of one that's "missing"

I see you're new to the forum, and have therefore probably not yet realised the absolute impossibility of thrashing out anything, including a dead horse, to the satisfaction of everyone here.

The range of both technical ability and mental health of members is enormous, a logarithmic scale would certainly be necessary for any quantification.

Each time a post is made on a thread, that thread jumps back to the top of the pile, and as threads get longer, the willingness of at least some members to read a thread through from the beginning drops off rapidly.

Once dispute arises, as it inevitably will, there may be a temptation for disgruntled posters to short-circuit the process, and submit their preferred version to VA's author, who may already be buried in mail - a possible explanation for his failing to have responded to your enquiry.

I hope I'm not being too negative, it certainly looks a very interesting piece of software, trying it out was already on my to-do list.

I should say that I'm fairly new myself, and not familiar with the use of either the Wiki or the Blog facilities of the site - perhaps they might be useful?
 
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Wow, 118 views including one definite "maybe"! I'll regard that as an overwhelming endorsement of my fiendish plan!

Simon B, yeah, I've looked at Alfredo's .rtf help pages (they date from the 2011 version and earlier) but I didn't find them all that helpful. There is just so much detail in this program and we need to tease it all out to get the best of it.

I realised that it's hard for people to react to something unseen, and also many will not have even heard of the program, let alone tried it. Some, like me previously, will have got as far as downloading and launching it, only then to give up because it didn't seem to make sense.

So, I've taken the first step, and produced an introductory tutorial, which you can find at:
HTML:
http://www.mcgee-flutes.com/VA-Intro.htm
.

Can I invite people (and especially people like you Simon, teetering on the brink anyway!) to have a look at it, and if interested, download the software (link provided) and give it a whirl. Costs nothing and could be the start of a whole new adventure.

Comments to here or directly, whichever suits you best. If I get positive comments, I'll press on and unravel the next set of mysteries!

Terry
 
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Great Terry, thanks.

I don't know about the DC removal on the O'scope, but on the FFT it certainly helped me. It gave a better reading on the low end. Otherwise the trace seemed stuck at the highest value in the lowest frequencies. I'll check again in O'scope to see that happens.
 
I use VA quite often and think it's the greatest thing since sliced bread. IMO, anybody who's familiar with standard hardware test equipment should have no problem figuring out 90% of it. It's set up in a very straightforward manner. The things I've wanted to know can probably only be truly and accurately described by the programmer, and he seems too busy to worry about it. He's the only one who really knows what's under the hood. Man, I wish I were 1/100 the programmer he is! FWIW, I agree somewhat with the earlier post- when a thread gets near 100 replies I almost never go back to it. Too many people, too much to remember and often OT.
 
Yeah, I agree about Alfredo's programming skills, wow!

Not sure I fully agree about how straightforward it is to drive intuitively. I spent a lot of time delving into just the oscilloscope section yesterday (and I haven't touched on two-channel operation or calibration yet), and right to the end, I was still finding great stuff. I may well have missed some!

Conrad (and others), can I get you to look through my latest page and see if you can answer any of the questions I've left for later. Just search the text for "(?)" if you don't want to read the lot.

Visual Analyser - Oscilloscope

Thanks!

Terry
 
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Don't have an answer to the DC removal thing quite yet. It seems only to work on the built in mic of my laptop. With an M-Audio card it seems not to matter.

I spent some time with the Spectrum Analyzer running in 1/3 and /16th octave mode, dual channel. I got the bright idea on looking at a microphone on channel A and the line level signal on B. By watching them jump around on music, it gave me a good idea of hot spots or holes. Not test signals or noise, real music.

Once the levels between mic and line were matched, it was pretty cool to watch both at different integration times (averages). If the mic (and thus speaker + room) was consistently different I made EQ adjustments. The sonic results are rather good, I must say.
Being able to see both channels at once was a big help and V.A. was great for that. Lines mode made it easy to see both.

If only V.A. had a channel delay, it would be great for getting the acoustic and electrical synced right up. I could not find one, but the method seemed to work well anyway.

The programming is top notch, for sure. I think he's done a fantastic job on the display traces, they look almost as as good a CRT.
 
Very nice tutorial, Terry! I installed it on my computer last year, but never got around to actually using it, something you have inspired me to correct.

OT: Poking around your site, I discovered my Holy Grail. Really superb stuff on flutes, and I sorely wish I could afford one of your instruments! After nearly 50 years of hacking on the instrument, it's the first time I've felt that a hardware change would really improve my playing.
 
Pano, I only see the little window when its not "Calibrated". You can try the Default Config to go back to being uncalibrated if you want. It's probably not that important.

On the Channel delay issue you mentioned earlier, there's something of that nature on the main Settings window. I haven't investigated it yet.

I imagine the DC Removal issue will become clear as we journey on. If not, it probably doesn't matter!

Thanks for trying!

Terry
 
Very nice tutorial, Terry! I installed it on my computer last year, but never got around to actually using it, something you have inspired me to correct.

I suspect many are in that boat, Sy. I certainly loaded it some year or more back, had a quick sniff around and put it in the too-hard basket. I'm enjoying delving, now that I've made some headway.

OT: Poking around your site, I discovered my Holy Grail. Really superb stuff on flutes, and I sorely wish I could afford one of your instruments! After nearly 50 years of hacking on the instrument, it's the first time I've felt that a hardware change would really improve my playing.

Thanks! I really enjoy flute making, it's probably been the most demanding thing I've ever done, and I've done lots! Now I'm bending more towards flute research, which means I've had to upgrade my audio facilities, which is what brings me to VA, and diyAudio. Funny how journeys evolve....

Terry
 
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Terry, I like your writing! Not much to add, but I think that the example of differential mode by measuring across a resistor, though perfectly true, isn't much use on an AC coupled system. In fact, I can't remember ever using a hardware scope in differential mode, and I do that a lot, while AC coupled. As for A cross B and B cross A, I haven't explored them, but once you have A/B and B/A, multiplication functions are often not included. It's too easy to get over range. I know there are two channel cross correlation functions on some analyzers- could it be something like that? I can't imagine that Alfredo wouldn't have just used A X B if that's what he was doing. IMO, a really useful function would be if one could measure current with one channel and voltage with the other, than display instantaneous power. That's then the path to both watts and VA and knowing the difference.