Guan, Emmanuel (Icefox), Kenneth and I got together on Saturday for 2 listening sessions, first at Emmanuel's place then at mine. We listened to a lot of stuff:
- Various preamps (DACT passive, Symphonic Line Erliechtung, Joule Electra LA-100 MkIII and the Minimax (the last 3 all tubed))
- Symphonic Line cd player
- Various dacs (Mensa Plus, custom pencil tube dac)
- Various interconnects (Slinkylink, Groeneberg, etc)
- Various speaker cables (Slinkylink, Mogami)
- Power filters (Blue Circle, Quantum Symphony Pro)
I'm going to put down what I recall and hope that the other guys can add their views as well. Here goes, in no particular order:
The 3 tubed preamps did not give much away in terms of transparency to the DACT passive. Nor did the passive give away any dynamics or bass. In general the passive sounded very natural and clean, but we had to crank it up to 1 detent short of unity gain for all the 2v sources. It produced satisfying volume, but sometimes we wanted a little bit more. Guan's pencil tube dac has a 3.3v output, which was better suited for the passive.
The Minimax was the giant killer of the 3 tubed preamps. It is a very small preamp, and only has 3 tubes. But it is packed to the gills. The large chokes are visible through the cooling vents. It went toe to toe with Emmanuel's Symphonic Line pre, which must cost easily 5x as much. At my place the Minimax had slightly better clarity, layering and top end extension that the Joule.
The Joule produced very smooth musical and non-fatigueing sound, perhaps easier to listen to for extended periods than the passive or the Minimax. But, it had a bit of extra sweetness to the treble and was a bit less transparent. I think that an inline bybee filter (Hi Wayne) will do the trick - as the bybee has been said to add a more natural and extended treble while also reducing noise and improving detail/resolution.
The Mensa Plus and the custom pencil tube dac seemed pretty darn close! There were some differences at first but they became much less as the pencil tube dac warmed up. We didn't focus on the dac comparison too much. Both seem to be great dacs. They are clearly better than the Sony XA777ES. The pencil tube dac seemed to be an improvement over the Symphonic Line cd player, but I note that we did not have a true digital cable at Emmanuel's place (we used a copper IC).
The IC/speaker cable comparison came up as Icefox wanted to try the Slinkylinks against his Groeneberg ICs. In his system, the Slinkylink seemed to add smoothness and clarity; it did not at all have the stereotypical bright silver sound. But, adding the Slinkylink speaker cable seemed to soften the sound. In his system, the Slinkylink IC plus Mogami speaker cable gave the best sound. Interestingly, at my place (I use the Slinkylink speaker cable) there was no such problem. Maybe next time I can bring the Nitro over to Icefox's place.
The Quantum Symphony Pro was the biggest revelation of the evening. Guan let us try it at Emmanuel's and my place. It is a parallel filter and, wow, it really made a difference! Smoother and silkier treble and smoother mids, tighter bass plus greatly increased coherence. We heard this improvements with all the different combos of equipment, at both Icefox's place and mine. It is an expensive piece, though ($600 new, $300 used), but you really do hear the difference. Kenneth is big on parallel filters and has 2 of the Symphony Pros, 2 Quantum Electroclears and 2 Blue Circle Noisehounds. He can tell you more of the performance of each of these parallel filters.
The Blue Circle Music Ring 1200 was only used in my system. We listened mostly with just the front end components plugged into it. At the end of the night, we plugged my eAR digital amp into it and my system's sound took a large step forward. The sound got much more open, bass got tighter, and soundstaging became more accurate. It did not seem to limit dynamics. The thing works.
Well, that's what I can recall off the top of my head. Let me know if there is anything I can clarify. Kenneth, Emmanuel and Guan should probably add their impressions to give a full account of what went on. It was a long day... we started at 5pm and ended at 2am!!
