Guys / Gurus,
I just wanna know your personal experience and impression about the vintage tubes listed below. Inputs are very much appreciated.
Here are some VERY GENERAL observations about some of the vintage NOS types tubes: TELEFUNKEN, SIEMENS, VALVO, LORENZ, and other German made NOS: These tubes are usually characterized by an impressive open "air" at the top end. The soundstage is large, even in mono applications these tubes have a great 3-D image. The midrange is ruler flat, and the bass is tight and accurate. These tubes have a fine sense of dynamics, and most are impressively quiet. These are not "warm" tubes, and to some ears their lack of midrange warmth may be heard as bright. I tend to think of them as accurate, and their clean, focused sonic image is astonishing.
AMPEREX, PHILIPS, MAZDA and other Holland/France/Belgium made NOS: These tubes are a great balance of a clean, airy top end, nice midrange warmth, and accurate bass. They are very pleasant, clean, and musical to listen to in hi-fi applications. Unlike other clean European tubes, these break-up impressively when overdriven in a guitar amp. The rare longplate versions are the same, but with even more soundstage space and detail. The Mazda adds a nice bit of dynamic punch to the sound.
MULLARD, GENALEX, BRIMAR, and other British made NOS: Like a warm British jacket of the finest tweed, these glorious tubes have an attractive sweet warmth in their midrange and lower regions. The top end is silky and pleasant, without being rolled-off. The best of these tubes retain a fine sense of "air" at the top, and the upper midrange is smooth and liquid. These tubes reproduce the human voice, especially female voices, with haunting realism. The rare longplates and Genalex versions have an eye-popping huge soundstage, razor sharp focus and detail, and an uncolored top end while retaining the warmth of the lower priced versions.
RCA, RAYTHEON, GE, SYLVANIA, and other USA made NOS: This group is very diverse. The RCA, Raytheon, and Sylvania blackplates are among the best here. These are very musical tubes with air and sparkle at the top end, warmth in the mids, and great bass. The RCA are drop dead beautiful in guitar amps, even the lower priced greyplate and longplate versions. They also have a wonderful "phat" gritty sound when overdriven in these amps. The blackplates and most tubes made for organs are very quiet. The greyplate GE is an all-around nice-guy tube to listen to, the longplate here possibly getting the nod for hi-fi use. The Sylvania greyplate and military versions are clean and a bit bright, but the Sylvania 5751 variants are very balanced and pleasant to listen to for hours. The GE blackplate 5751 triple mica is also in great demand as a very musical vintage tube. The RCA 5751 is more like the Mullard, with a rich warmth and wide bandwidth. Currently, the USA made tubes are a nice surprise with their low prices as compared to the European types.