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[negopus]

I always wished that MC could have some more technical-oriented visualizations of its audio output, such as an oscilloscope and a spectrum analyzer with a scale indication, adjustable ballistics and so on... But I understand that MC is growing in different directions -- the mainstream home entertainment market drives its development --, so probably we will never see any technical orientation in MC visualizations. So I had to search for alternate ways of getting a technical-oriented display of audio in MC.

First I tried plug-ins. MC features a DirectX adapter plug-in , , that is developed using the commercial library Adapt-X http://www.chronotron.com/content.php?page=products#adaptx, or better Adapt-X Engine SDK, that can load professional-level DirectX plug-ins into MC. There is a DirectX plug-in named FFX-4 (freeware from VB-Audio) http://perso.wanadoo.fr/vb-audio/us/products/dxrack/dxrack.htm. There is also a free VST to DirectX adapter, called VST DX Wrapper Lite, from SpinAudio http://www.spinaudio.com/products.php?id=33, that allows a VST plug-in to be used inside a DirectX host application.

So, chaining DirectX adapter, FFX-4 and VST DX Wrapper Lite, you should be able (maybe with some delay given by chaining) to use professional-level VST plug-ins in MC. This chaining technique was called "the Johnny Carson method" by Absurrrd in a thread in this same forum http://yabb.jriver.com/interact/index.php?topic=29488.msg203356#msg203356.

But there is a problem. The refresh rate of the DirectX adapter inside MC is very low. So this method is almost unuseable for visualization.

By the way, I have tried FFX-4 for Winamp, for which there exists a specific version. Its refresh rate is accettable, but using it anothe structural issue shows out. Winamp, like MC, has a playback buffer. It compensates internally its own visualizations for the delay introduced by that buffer. But plug-ins, primarily intended for signal processing, don't have that delay compensation at their input. Signal is feeded to them with no delay, so their visualization appeears actually ahead of the audio. The buffer size in Winamp cannot be set below 200 ms, so the visualization-to-sound delay is still noticeable even with a buffer as small as 200 ms.

In conclusion, in order to support visualization plug-ins, the DirectX adapter for MC should:
- have a faster refresh rate
- have a "visualization mode" where a signal delay (compensating the internal buffer) is introduced before sending the signal to the plug-in, and the output of the plug-in, that is delayed, is discarded. The plug-in is used only for display, after all, not for signal processing. There could be a check box "Visualization only: compensate buffer delay and discard output".

Continuing the quest for a serious audio visualization, I realized that most audio cards can route their output back to their input (in the digital domain, I hope). You can see that feature in the Windows Control Panel, or, if the audio card driver in not "Windows standard", in the control panel of the driver itself. I discovered that feature a long time ago, but I just removed the concept from my head saying "this is dangerous, this likely to give feedback". What a mistake! There is a vast array of possibilities that come from that usage of the audio card.

The input of the audio card can be visualized as an oscilloscope or a spectrum analyzer. There are many small utilities around that do just that. There are also professional-level VST plug-ins that perform that task

The most complete VST plug-in that I found is InspectorXL from Elemental Audio Systems http://www.elementalaudio.com/products/inspectorxl/. It includes a level meter, a spectrum analyzed (with running spectrogram), a stereo analyzer (with X-Y, Lissajous display and more) and a statistics module, to detect "digital overs". At $89, it is reasonably priced, if you are interested in serious audio metering. There is also a free version too, named Inspector, that has only a basic meter and spectrum analyzer.

The two alternatives to Inspector are quite expensive, and not viable in a PC environment.

SpectraFoo from Metric Halo http://www.mhlabs.com/metric_halo/products/foo/ costs $400 to $800: too expensive for an amateur. Also, it is only anailable for the Mac platform, not for Windows. However, it performs measurements that go beyond my wildest dreams: bit-level display, transfer funcion measurement, and also has forensic-oriented features.

Hardware meters from DK-Audio http://www.dk-technologies.net/products/selchart.php?prodgroup=msd have an LCD display, and look actually like a LCD monitor. They have an ergonomic problem. In order to be effective, they should be placed right in front of the user face, who should not turn his/her head in order to see the display. These meters have a VGA output that can be hooked to the computer monitor, but you have to switch between the computer output and the meter output, and while watching the meter output you loose all the computer functionalities.

In order to use VST plug-ins, you have to run a software rack that takes its input from the routed output of the audio card.

I am trying Forte from brainspawn http://www.brainspawn.com/  right now, and it performs well. No noticeable delay, and stable behavior.

There is also Virtual Mixing Console from SpinAudio http://www.spinaudio.com/products.php?id=38, but I haven't tried it yet.

Both of these applications can host virtual instruments (VST and DXi), so you can use them playing a MIDI keyboard in real time to control virtual istruments.

I found that using the Inspector VST plug-in with a suitable host is a viable way to display the audio output of MC with a techincal perspective.

[jgreen]

I've been trying the FFX-4 plugin negopus mentions and I'm happy with the results.  One additional benefit I've found is that multiple plugins chained within the FFX-4 do not seem to create the same instability that separate multiple plugins can within the MC DirectX host.  Others had mentioned instability with more than one plugin, and I had started to see it myself.  But the same several plugins hosted within FFX-4, which is then hosted by MC, seems to work quite well.