Audio Valve: Baldur 200+;       { $23,000; 170+ wpc }

These are a physically imposing pair of amplifiers. Weighing in at 79 pounds and occupying a 17.25" square x 14" high piece of the room ... EACH!

The result of all this weight and size is an amplifier which is sweet and delicate sounding when called for, yet authoritative and in control when needed. The tubes used are the very musical 6AS7 output tubes, which are biased automatically by the amplifiers proprietary internal circuitry. The result is an excellent balance across the gamut of musical styles and tastes. I played everything from delicate original instrument chamber music and soft vocal solos to loud, rowdy rock and large orchestral pieces ... all at various volume levels. The Baldur sailed through it all with equal aplomb. Two common knocks against vacuum tube amplifiers in general is that they are too fussy or that they don't provide the bass power and control of their solid state brethren. Well, the Baldur is only one of many examples in the tube world which makes either of those statements meaningless and untrue. Sure, there are some tube (valve) amps which require a bit of fussing or which don't have very good bass ... sometimes both shortcomings ... but not this one and certainly not all of the others either!

The Baldur had a musical footprint which was obvious yet paradoxically "uncolored" in terms of it's sonic qualities. There was no distinct impression that this is a valve amplifier garnered during listening tests. It's bass is tight and well controlled without being over-damped and "dry" sounding. ("damping" is the electronic means by which an amplifier controls extraneous woofer motion; commonly referred to as "damping factor") Track after track left the impression of a well focused yet large and deep soundstage. Ambient retrieval is very good, indicating a low noise floor. {This is an area where all the solid state amplifiers have an advantage over all the tube amps in this roundup ... they are inherently less noisy when there is no music is being played.} The noise floor becomes a factor in retrieval of ambience and overall detail. The Baldur did give a very good sense of ambience when called upon and the images it portrayed were quite holographic and correctly proportional to each other. High frequencies are rendered without a hint of glare or overdone presence. Cymbals, bells, triangles and the harmonic tones of a children's choir are very well served by the Baldur. Another area which can be well noticed between differing power amplifiers is the sensation of correct (musical) pace and "timing". The Baldur, along with most others in the roundup, is a real champ in this respect, always leaving the listener with the feeling that the reproduction is spot-on. The transparency of any amplifiers ability to peer into the soundstage is something which can not be measured, but which is immediately apparent to anyone who has done an A/B with two amps having vastly differing capabilities in this respect. The Baldur is a very transparent amplifier, peering clearly into the soundstage and allowing us to sense the spacing between individual instruments and vocalists quite clearly.

Although the soundstage wasn't quite as large as the Parasound JC-1 and Krell FPB 450Mcx, as transparent as the Electrocompaniet AW-400, as well defined as the Simaudio W-10 and Sunfire Signature or as rich in the "gravitas" area as the Rogue Zeus and the Marsh A-450, it was a terrific blending of all the above, and well worth anyone's consideration.

Audio Valve: Challenger 150;    { $8,859; 140-180 wpc (depends on output tube type) }

The Challenger 150 is in the middle of Audio Valve's other line of amplifiers. Unlike the Baldur line, it is not a class-A amplifier. It can however, utilize differing output tubes, allowing the owner to pick the tube which suits their musical preferences the best. The tube used during this roundup is the EL-34 tube, which is highly regarded for it's fluidity and smooth midrange ... albeit at some loss in power compared to a 6550C or a KT-88. (to name just two) The build quality is exactly what I've come to expect from Audio Valve ... excellent, with no criticisms whatsoever.

Sonically, the Challenger was challenged by it's rivals in the test and most clearly by it's brother. The soundstaging is excellent and well-defined. Transparence was very good yet compared to the best of the best, it was slightly less focused then some, and didn't have the bass power and control which I experienced with the Baldur. Please bear in mind the differences are minimal and the cost differentials are large.[ although in my mind, worth it ] This is a very good amplifier. I feel that if it had come with 6550C output tubes I would have liked it even more. I am looking forward to hearing the amp again at more shows. The Audio Valve "house sound" is very appealing to me since it is more focused on the music instead of the hi-fi equipment. (PS: Their pre-amp is a knockout too!)

Joe Shanaphy

Audio/Video Editor, That's Life! magazine

(201) 785-1055

[cell] (201) 669-8700