I've been a real fan of True Dimensional Sound's "TDS Passive Audiophile" and regular passive version, for 15 years now and have one in line with a Vincent KHV-111 hybrid headphone amp and in line with a modified MF X-Cans v.1. In fact I had just recently found the Acoustic Research TDS 202 model on line for $30 instead of the original $129, and have it now twixt the AudioNote M2-B preamp and Croft Polestar 1 power amp. Having owned the pre-Acoustic Research models for some time, I lept at the chance to own the later version, and at such a great price. One may access many reviews on line that can explain more in depth what it does, but one major benefit for me is it's ability to increase gain by as much as 3db, which gives my AKG-702's more room to breathe, so to speak, through my Vincent hp amp. But, it is more than just a gain machine, as the reviews will attest to. Some love it (me) and some don't. Also, a couple of my systems just didn't get along with one in situ. And then there's the purity of signal folks that frown on added complexity. But, for me, and especially with headphones, it's a beauty, eh?
Hey Y'all....I just hooked up my very insensitive Morel Octave speakers (in Ferrari Red, of course) to my 25 watt per channel Croft Polestar power amp with the TDS between it and the AN preamp...and wanted to report that the TDS gives these Morel's the much needed air that this pre-TDS system just didn't have. 25 watts RMS max is not a realistic power source for these 83db efficient speakers....but Croft power is not just any power and combined with the extra 3db increase of the TDS, makes the difference here. No clipping at more than realistic levels, either. So, not only does the TDS restore some of the original signal lost in the recording and transfer processes, but also can give a level boost to systems in need. This system is very listenable now. Happy boy here....JM