There is an issue with lucid mode turned off with a weird ringing. It seems to work just fine with old and new mode turned on. I have been mostly listening to my HD800's, though. I will try to get some more time with the HE500's and see what I think.
I have been monitoring this thread since it was started because I take the Taboo Mk III very seriously and am keenly interested in everyone's experience with it. We have a support forum on our web site for the Taboo Mk III which can be seen here: http://www.decware.com/cgi-bin/yabb22/YaBB.pl?board=TABOOMK3 I would invite any of you to join it, especially with support questions, as that is where I prefer to answer them. Of course you are also welcome to e-mail me directly at firstname.lastname@example.org with any support questions or comments you might have. Also registration in our forum has a tricky captcha where you actually leave out the first two and the last two characters. A simple trick that eliminates spam bots.
The reason I'm posting here this evening is to talk about lucid mode and single-ended headphone cables.
The taboo design has a floating output stage, meaning that the negative speaker jacks are not connected to ground like is typical in 99.9% of amplifiers. This is what makes it so Taboo, and what makes possible it's Lucid Mode feature.
A single ended headphone jack has only three wires, not four. That means the grounds for each channel are tied together. Since the Taboo will not tolerate this, the ground for the headphone jack can only come from one channel or the other. To get around this issue, the ground is tied into the lucid mode switch so that lucid mode itself can create a virtual ground for the headphones. That means that original lucid mode must be ON at all times for proper operation of single ended headphone cables. Turning the switch off will cause the virtual ground to vanish leaving one or the other channels without a ground. This will cause strange things to happen sonically, which includes the experience I quoted at the start of this post.
It's really very simple. Keep Original Lucid Mode ON when using headphones that employ single-ended cables. Original Lucid Mode is a natural and accurate frequency based cross-feed that you would usually want to have ON anyway - with virtually all headphones.
Otherwise, get yourself a balanced cable for your headphones, that way the grounds of each channel are separate at all times, just like loudspeakers... which is partly why balanced sounds better than single ended cables with the Taboo Mk III.
I will be writing a paper on New Lucid Mode soon, as it can be used as a tool to evaluate the quality of many recordings. Because it works by revealing information hidden in the recordings that is out of phase from channel to channel... rendering it silent to the ears... it lets one evaluate how much phase angle discrepancy there is between the various tracks before they were mixed down to two channels. In my paper I'll explain exactly how that works... but the result is simple. Audiophile recordings that were done with purist practices and are free of excessive phase distortion between tracks caused by microphone placement, electronics and effects busses, will sound absolutely stunning without New Lucid Mode turned on. Then when New Lucid Mode IS turned on, you will hear almost nothing change. On the flip side, hearing a big change when New Lucid Mode is used is indicative of a less than great recording and if analyzed, shows much of how the recoding was mixed and mastered. Of course fake or digital reverb effects common in main stream recordings are not going to sound good with New Lucid Mode turned ON.
Hope these insights increase your understanding of the Taboo which in turn increase your enjoyment of it. This is a very serious listening machine for very serious headphones and very serious recordings. And thanks to New Lucid Mode, half of the 80% of less than great recordings can now be heard as though a mastering guru made the recording. Certainly increased the size of my serious listening library!