I hope I don't spoil the fun for anybody by posting my tube impressions. I only listened to part of the pack and skipped over some that I already had at least one of. In the end the RCA blackplate/cleartop combo still is my favorite. These impressions were written as I listened to each tube so the descriptions probably aren't the greatest. Here goes:
Using a Terratec EWX 24/96 soundcard connected to a PPX3 with my cables and driving AKG K 271 Studio headphones. My current favorite is using an RCA blackplate driver and RCA cleartop outputs and I'll refer to these as my benchmark combo. For the record, I do not particularly like the seemingly popular trio of RCA cleartops, what that trio does to transients should be illegal (it's very sloppy with them), although I love them as output tubes. Each of these descriptions were written when I listened to the tubes so of course you can expect my favorites to change over time.
August 23
Golden Dragon 6FQ7 trio
Tube physically looks a lot like an Ei tube.
Very good overall. Excellent soundstage, full-sounding bass with nice body and excellent slam while not sounding too flabby, a bit distant sounding although vocals don't sound too recessed.
I am quite impressed by the wide soundstage these things project. It makes some music sound a bit distant, though. At the same time imaging seems good although some vocals sound a bit disembodied.
Overall a nice tube but the at times overly spacious and somewhat distant soundstage takes away from the tube's otherwise nice pace. Vocals lack body and coherence and that really can detract from a lot of music. Transients seem to be handled well but slightly rounded off but not nearly as bad as a trio of RCA cleartops (those things destroy transients). I will have to try these as output tubes with an RCA blackplate driver, I think they will complement that tube quite well.
RCA blackplate 6CG7 driver/Golden Dragon FQ7 outputs
Now that's a bit better. Soundstage narrowed a little bit, but everything is much more coherent. Imaging is better than before and transients are sharper. Bass is not quite as deep and full as before but still quite nice and more controlled. The sound just seems more evenly balanced and vocals are quite a bit better than before. This is an awesome combo and offers some competition for the RCA cleartops as output tubes. Like the cleartops, they aren't the best as a trio but really combine well with a forward, fast driver tube like the RCA blackplate. I would seriously like a pair of these to use as output tubes, too bad they seem to be impossible to find on the 'net.
August 24
Raytheon Short-Plate 6FQ7 Trio
Rather distinctive short gray plates make these stand out appearance-wise.
The best trio of tubes I have heard so far and holds its own against combos of different makes of other tubes. Bass is lighter than the Golden Dragons as well as slightly lighter than my benchmark RCA blackplate/cleartop combo, but I wouldn't say it was lacking at all and it maintains very good impact. Good imaging and positioning, nice soundstage although it's not as wide as other tubes I've heard. Vocals are just slightly recessed, but not overly so. Slightly tipped up upper midrange and lower treble similar to my RCA blackplate. Detail is quite nice and transients are all there and not being rounded off or being turned to mush. Good pace and rhythm. I would put these on the slightly fast side, although not as fast as an RCA blackplate. These are quite well-rounded overall and it seems their tonality meshes very well with the PPX3/AKG K 271 Studio combo, reducing the forwardness of the midrange of the 271s as well as slightly reducing the quite plentiful bass that the PPX3 inherently has and the 271s are good at producing. This is the first set that I've heard as a trio that I seriously like which is quite impressive to me. My RCA blackplate/cleartop combo will still edge it out in some ways but these definitely offer a nice alternative.
August 25
Mazda 6CG7 driver/Selectron 6CG7 outputs
Unique short-bottle and short-plate on the Mazda tube, Selectron tubes look somewhat like some GE and RCA tubes I have.
Really not a dramatic departure from the Raytheon trio. Very slightly lighter in the bass although it also sounds better controlled, not as tipped up in the upper midrange and lower treble, and a more relaxed and slower sound overall. Midrange is more pronounced than the Raytheon trio. The soundstage seems slightly narrower. Can't really say anything negative about them though.
August 26
Sylvania 6CG7 trio
Gray ridge-plates.
Sound is a bit on the slow side and a brighter tilt than the Mazda/Selectron combo, although not bright overall. It seems as I have gone through the tubes the bass has gotten lighter with each set, and this is no exception. It's all there and sounds nice but just doesn't stick out very much. Midrange is still slightly recessed, but none of the tubes I have heard so far have had a midrange that is like the RCA blackplate. These tubes are very smooth sounding and relaxing overall and like my black-plate Sylvania have far less than sibilance than I've heard in other 6CG7/6FQ7 tubes so far. Soundstage is wider than either the Mazda/Selectron combo or Raytheon trio and similar to my benchmark combo.
Tungsol 6CG7 trio
Look just like my Dumont-branded tube except very slightly different shields on the top of the filaments and black plates on the Dumont, which leads me to believe my Dumont tube is of Tungsol manufacture.
Spacious sound almost as wide as the Golden Dragons, but much more coherent imaging than those. Deep, tight bass in just the right proportion to the rest of the music that is notable for how well controlled it is and how much punch it has at the same time. These just have a very nice sound overall and I think I can safely say these kick the butts of any other trio or combo I have tried out of the tube pack so far. The first set I have been able to put in and give an undoubted thumbs up to. Just plain excellent transient response and excellent detail. Hell, they are presenting some serious competition for my benchmark combo. I have got to get me a trio of these!
I didn't try all the tubes in there since I didn't have enough time (the box was sealed back up for a week waiting for the first chance I could get to the post office) but tried about half of them. I was quite impressed with the Tungsol tubes, but even that combo didn't surpass the RCA blackplate/cleartop combo.
