Summary:
I just added a pre-owned solid-state Classe Audio Thirty preamplifier to my HiFi system. The used preamp cost $800 and included a remote and a phono section, as well as both balanced and unbalanced inputs and outputs. It replaced my trusty Conrad-Johnson PV-2 (RRR) which was also purchased second-hand for $300 some 14 years ago. As I am bi-amping my Sonus Faber Concerto loudspeakers, my "new" Classe preamp drives my two home-built stereo power amplifiers (through two sets of Audioquest Ruby interconnects and a Monster RCA tee connector). No electronic crossover is employed to mitigate phase shift inconsistancies, although some resistive attenuation (T-Pad style) has been employed to balanxnce the gain of the two power amplifiers. My 70 wpc Tweeter PA is a simple push-pull pair of 6550C pentode vacuum tubes in ultralinear topology. My 120 wpc Woofer PA is a modern push-pull MOSFET topology. Both home-built PAs employ audiophile grade caps, wire, connectors, and solder. My analog and digital signal sources are "Class B", or equivalent. Most importantly, my listening room is outstanding, and also employs dedicated electrical service.
The Classe preamp is a clear upgrade to my HiFi system. Its tonal balance is very similar to my trusty old 6-tube CJ, except that the Classe low bass performance goes both deeper and has better visceral impact. The three dimensional soundstage with the Classe is a bit wider, with about the same depth and height. Air and space surrounding images, as well as image location are both consistant and clear, and there is little difference in this regard between the two preamps. The surprise is how quiet the background noise is with the Classe compared to the CJ. The background noise I was accustomed to has been reduced by at least 6 dB (a linear factor of 4 times) using line level inputs, and by at least 10 dB (a linear factor of 10 times) using the phono input. The remote works very well and is a welcome addition to my HiFi system, as is the mute switch and the general ergonomics of the Classe preamp. The musicality I have come to enjoy and expect in my HiFi system even seems to have improved. Maybe though the musicality is really just as good as it was, but my enjoyment has simply increased due to the bass and background noise improvements, as well as the convenience of a volume control remote and a mute switch. In any case, the musical experience is full of foot-tapping enjoyment.

I happen to be employed as an electrical engineer, specializing in the Radio Frequency design of cellular telephone systems. I understand the way electical circuits work, and am intimately familiar with FET, Bipolar, IC/Op-Amp, and vacuum tube devices and technologies. While it's nice to know how your HiFi works, it's much nicer to enjoy the music it plays for you.

I am distressed when I hear angy rhetoric putting down one technology and elevating another in these web threads, from my fellow audiophiles. The fact of the matter is that a good designer/engineer can get great sound out of any one of the technologies that I've mentioned, as long as that is the design goal. All of these technologies offer their own set of tradeoffs. Yes, some technologies might represent a bigger challenge than others, and I agree that it takes an inept individual to design an unpleasant sounding vaccum tube circuit. However do yourself a favor and do not fall into the trap of eliminating prospective HiFi equipment candidates from your quest because the devices in them are not "fashionable". Let your ears and your wallet decide what makes sense in your HiFi system. Remember above all that the device (ie: transistor, tube, etc.) is but a part of the circuit, and it is the circuit that must ultimately be effective at conveying the musical performance. A good circuit designer/engineer should be judged on the enjoyment their circuit brings you, not on which devices they used in the circuit. Being from an engineering discipline I would also suggest paying attention to the mechanical engineering aspects of the electrical engineering before you. The circuit layout should be both clean and robust, using the highest quality construction techniques, so that reliability and repairability can be expected to be good. The designer/engineer should always design products for the general public's use so that they can be used successfully in all but the harshest environments (including within strong emitted RF Fields from nearby digital electronics, etc.), since you never know where the product might be installed. I must state that the Classe preamp is outstanding in this regard.

Finally, always keep in mind that the dealer is just that. The dealer is not the manufacturer, and accordingly the manufacturer should not be judged by dealers, and more specifically dealer's salespeople. On the other hand, a well chosen dealer can be a powerful ally to you, helping you improve your enjoyment of your HiFi system. The best dealers will rally behind your quest to ensure that your purchase satisfies you by allowing you either an in-home audition up-front, or a reasonable return policy.

Kind Regards, Chris
http://www.wb2vvv.com