Hi Gang. What a great sounding amplifier. Had the pleasure of auditioning a friends amp [stock tubes] in my rig. We didn't mess with any tube rolling, never even opened the hood .... just sat there intoxicated by the reproduction. I would have loved to do a little voicing with nos tubes but never got the chance. I must say that I am a little perplexed as to why Andy would state that the 12av7 is "crap in a glass" tube! I beg to differ here as my experience with subbing a 12av7 for most any brand 12at7 has always been a huge benefit in virtually every circuit application. Regardless of whether it's applied as an input tube, phase splitter,driver, cathode follower etc,the 12at7 gets stomped on every time. Furthermore, even in low resolution circuits like guitar amps, juke boxes, pa amps and the like. Although the 12av7 has marginally less gain than a 12at7, it's simply a far more musically engaging tube in my experience. Excluding the wonderful sounding triple mica genelex A2900 and perhaps the Osram B309, any brand of the 12at7's are mediocre at best. The pricey telefunken ecc801 as well as any of the nos mullards[including the m-8162]must be considered the most over rated tubes out there today. I can certainly understand the accollades and hype awarded to the famous telie ecc 803[12ax7]or ecc802[12au7]as well as the early long plate mullard versions of those same tubes types as they are in a whole nother leaugue altogether and certainly deserve their stellar reputation. If there is one particular example of an audio tube that could be described as "crap in a bottle" the 12at7 would surely fit that description. Try a nos black plate version 12av7 [d getter] and compare, it'll surely make you giggle. The Canadian made Marconi branded 12av7 [d getter] is a fabulous example and relatively inexpensive to boot.... a very smooth and relaxed presentation, yet vivid and dynamic with a deeply layered midband and an extended treble range thats always sweet and airey. Worth a try gang. cheers david
