I was recently given the opportunity to try 14 tubes in my Sunrise II so I thought I would post these notes. I started off with the ones I thought I would like the most and then once I found the one I thought I liked the most ,
I did more listening to confirm the conclusion and make some notes.
I completed all my listening, playing flac files, USB into a Musical Fidelity VDAC , into the Sunrise II , using Fostex
T50RP DBV#3 mods. I used V shaped equalization from 1000HZ up in both directions. I am 67 years old and my ears
are not what they once were. Also, I start to evaluate tubes by listening to the higher frequencies and hunting for
sounds and spaciousnous I have not previously heard in recordings. I focus less on the rest of the frequency spectrum.
This is clearly my number one choice. It is detailed and smooth. It does not provide a great sense of space and air
around the vocals but it is very good. The sound is clean and clear with a crispness to sharply struck piano keys and
possibly a slightly laid back bass mid bass but not much. Some might not consider this tube musical but I strive for
accuracy in a tube and often when I'm listening consider how the recording was miked and mixed. This Telefunken
is excellent throughout freq range.
To me, the next three tubes were very close in performance, I am sure I could differentiate between them but it
would take more time than I was able to commit.
This tube is very close to the TF. It might not have quite the clarity and detail but it was very clean. Extremely low
bass stands out on this one although it may be a touch bright. The bass was tight and the piano notes were clean
and clear. This one is a clear winner, especially for the price.
Tesla E88CC (Crossed Swords)
I listened to this tube quite a bit but didn't take many notes. The vocals on this one seemed a little more spacious
than the TF . It lacks the sub bass of the TF but It is musical and very pleasant to listen to. Those who find the TF too
clinical may take to this one. I shopped around for one of these for a while but could not find a crossed swords version
at a reasonable price.
Most tubes seem to improve once heated up and that goes in spades for this one. Not quite as detailed and clean as the
TF in the high end and the voices seemed a tad recessed, however, I have noticed that the slightest change in volume can
cause this perception. The very top end may be rolled off. Some may appreciate this because it will not sound as clinical as.
Bass is well controlled. This tube does everything well but doesn’t stand out in any one area.
Valvo E88CC 75L Delta PO Red Label
Not quite as dynamic and crystal clear as the previous three but close. I didn't consider this tube to be the most clinically
clean and detailed but at the same time it is not the most musical because its a little too revealing for that. Some would
find this a pleasant tube listen to all day. I felt this one was very similar to the Tesla E88CC (Crossed Swords) but a slight
step below it in performance.
The poor mans TF PCC88. As you might expect this tube is like the little brother of the crossed swords version. Its
performance is very similar and just a slight step below . The performance is so close that many listeners would not be
able to tell the difference. Like many of these tube it may get even better with more burn-in.
I didn't listen to this tube for long but I was surprised that I liked it significantly more than the 12AU7 version. I didn't
like it as much as the previously described tubes, but it was better than I thought it would be. Both of the Psvanes
seemed a little bright and somewhat strident.
Like the 12AX7 version of this tube, it sounded detailed but not clean and smooth. I attributed this to the slight brightness
I perceived. Clearly struck piano keys sounded wonderful but violins were a little bright. This is not an open, airy, and
musical tube. It sounds like a Telefunken copy that has been done very well but hasn't quite gotten it right.
As you would expect, this is a very musical tube. Female vocals sound wonderful and there are no harsh tones in the
instruments. This tube sounded very much like an Amperex 6201 PQ that I have. Everything sounds so very nice and
pleasant with good detail, but you can't hear everything you can hear with the best vintage tubes...not quite as crisp.
This tube has the detail of the Psvane 12AX7 but somehow more interesting and a touch less strident.
This tube had not been burned in much but it surprised me, especially for the price. Didn't listen to it for long but what
I heard was clean, detailed, and very musical. This tube could be a real winner after more burn-in.
Novosibirsk 6N1P EV
This tube hand only been burned in 6-7 hours when I listened to it. I wasn't impressed and didn't think much of it, but
upon checking the bias adjustment I found that this one had changed a lot after it heated up. After the bias adjustment
it sound much cleaner and smoother. It was still somewhat dark but promises to be an extremely good value.
Just as I completed trying out these tubes, I received a 50s Sylvania 5751, black plate, triple mica, rectangular getter. Its hard to judge tubes, based on memory, but I believe the Sylvania surpasses all of the above. Of course, at $110+, I was hoping it would and I wasn't let down. I haven't evaluated it for lower frequencies, but on well-recorded cuts, the vocals are astounding. I am hearing an air and soundstage on Pink Floyd cuts that I had never heard before. Now I'm wondering what the 50s Raytheon 5751, black plate, triple mica tubes are like.