Anyone listen to Zu Audio's Definition Mk3?

Within any particular "camp"-SET, OTL, pushpull pentode, solid state--there is at least the same amount of variability in sound as between the camps. I can think of quite a few tube amps that sound leaner, and more brittle than the vast majority of solid state amps.

I agree that the Atmasphere OTL (which I like a lot) is on the leaner side (not as much upper bass as many tube amps), but that is hardly an OTL characteristic. For example, a Joule OTL is a much warmer sounding alternative. I don't think one can get the same kind of liveliness and "jump," combined with reasonably high output, as one can with a good OTL amp.

SET amps can be very nimble and dynamic sounding, WITHIN their admittedly narrow power delivery range. With the right speaker, a low-powered 2a3 SET can sound far more alive and dynamic than almost any solid state amp and can hang with OTL amps.

I had a First Watt amp (J2?) in my system for about two weeks. I liked the sound--clean, clear, grain free and musical. But, the sound is still easily identifiable as solid state--slight "edge" to the initial attack of the note, not as spacious soundstage, less of a sense of ambient "fill" and natural decay of notes. I would have no problem with living with that particular sound, though I prefer my SET and low-powered pushpull amps.

With really good low-powered pushpull amps, I don't hear any "grunge" to the sound--I get plenty of clarity and a very tight punchy sound. But, the tight bass also sounds a touch mechanical (bass tends to sound the same regardless of the recording) and less tunefull and differentiated than with good SET amps. The "cleaner" sound also seems a bit devoid of ambient "fill" and natural sounding decay of notes (whether these qualities are artificially created distortions of SET amps, I really don't care because I like them). Still, I like the sound of certain pushpull amps a lot. I am currently running a great sounding pushpull amp that puts out a whopping 5 watts per channel that sounds fantastic.

A friend had a HP200/Radia combination. I liked the sound of that combination with his Sonus Faber Anniversario speakers. My primary gripe had nothing to do with sound--the steps on the attenuator are too course for finding the "right" volume.

While the performance was very good, there was no mistaking the sound for that of tube gear--there was still a slightly brittle edge to the initial attack of notes, and it was lacking a little bit in low level dynamics (good tube gear is more lively at lower volumes). The "glassiness" will probably be something that cannot be erased completely. I heard that with my friend's system, but, I did not find it to be nearly as bad as with other systems I've heard. While your amplification chain may partially be the source, the biggest culprit tends to be source gear, particularly digital sources like cd players and music servers (actually a lot of CDs themselves a mastered to have that kind of sound). I hear that problem with my all-tube amplification chain when playing digital sources (particularly my music server vs. my cd player).

I have not chosen to try to "cure" that problem because that would probably mean turning the sound to mush (something one can easily do with choice of tube gear).

Charles1dad,

Thanks for the interesting discussion of the Dueland components. I can easily experiment with my own system (crossover for each speaker is in three external boxes). Do you have any experience with their inductors?

Charles1dad,

Thanks. I know Dueland has been getting a lot of favorable write ups for their capacitors. I would expect that the same ears are used in designing other components, but, the science and art of making capacitors is quite different from that of making magnetic components. I have not really heard about their inductors, so it is good to hear from you that the word of mouth is favorable. It sounds like Dueland is another Audionote--good with multiple kinds of parts.

2a3nut,

Lowthers, and other full range drivers are amazing in their ability to tease out detail and perk up music. For me, almost all implementations I've heard were just too rough and peaky and seemed to "shout" too much for my taste (I still like the speaker). The most interesting Lowthers were the ones with the field coil magnet structure. The best implementation I heard of Lowther drivers was a three-way system made by Horning--a modified Lowther driver was used as a wideband midrange driver.

For full range drivers, I prefer Feastrix drivers. They have the same sort of issues with peaky response and poor bass, but, not nearly as much so as Lowthers. Unfortunately, they are WAY more expensive than Lowthers. A really interesting newcomer to the full range game is the Taiwanese firm Tang Band. I heard a few speakers using their full range driver, both in full range speakers and as midrange/tweeters in two-way designs. They manage to deliver the kind of dynamics and liveliness of full range drivers with surprisingly natural tonal balance. The Tang Band speakers are also MUCH cheaper than the competition.

I recently heard a system that uses an old Western Electric 756 full range driver as a woofer midrange in a two way design. This was a quite nice sounding system whose primary weakness was a lack of deep bass.

Chrles1dad,

I don't think I've heard PHY drivers. If you have, I am interested in what you think. I find that you provide a lot of interesting and well informed comments in this forum as well.

Another "full range" speaker that I heard that really blew me away (don't know why I forgot about them until now) is a circa 1940 Jensen field driver (13" cone, built in tube power supply). I heard a system that uses this driver crossed over to a tweeter at, I believe, 8 khz (all but the highest octave being reproduced by the Jensen driver). This is the best overall sound I have heard from a full range or nearly full range single driver system. There was very little of the midrange peakiness of full range drivers--the sound was rich and warm and good with even large symphonic works (a problem for other full range drivers like the Lowthers), and bass was surprisingly decent. It is VERY unfortunate that this is an extremely rare speaker and there have been no successful attempts at cloning this driver.