Mcpherson,
No worries, it's certainly not a silly question. I'm not confident that I can answer your question about the brightness of your system to total certainty, but I can perhaps explain my earlier comments a little more clearly.
I want to make sure that my comment about the slight smearing is in the proper context. I was comparing Telefunken rib plate 12AX7 to Telefunken smooth plate 12AX7 in the signal tube position of my Rogue M180. The driver tubes were held constant with Telefunken rib plate 12AU7. The Telefunken were already my favorite tubes for detail, dynamics, speed, tone, and certainly clarity. The comparison between the smooth and rib plate is really getting down into the small details, I like either one better than anything else I've had in my system, and I could live happily with either of them and never look back.
We were listening to acoustic guitar with the rib plate 12AX7 first, then swapped it out for the smooth plate. After a few moments we realized that a little bit of information had been lost in the sound of the strings in the trailing edge of the notes. At the edges of these notes the rib plate was more convincing, the smooth plate just very slightly fuzzy. But as I mentioned before, I could live happily with the smooth plates.
I think the rib plates have a smooth sound, which to me means the sound isn't edgy. I just think rib plates provide a little more musical information around the edges of notes than the smooth. I was on another thread where the discussion included RCA tubes (which I used before moving to Telefunken) and one someone commented that Telefunkens were a little brighter sounding than RCA, so perhaps changing tubes could help you. I moved to Telefunken because I was hearing dynamics and clarity. I've never had to battle brightness in my system, and I made the change too long ago to remember that aspect of the RCA sound. But along those lines, RCA is warmer than Telefunken, and Mullard is warmer than RCA. If the other Audiogon member's comment is indeed correct, then maybe changing tubes could solve the problem of brightness in your system.
You didn't mention anything about the rest of your system other than the Focal speakers - do they have beryllium tweeters?
I asked the guys at the stereo shop today about your questions. Several comments were made, but there wasn't too much discussion, so I'll just relay the comments: (1) Focal are bright sounding speakers, (2) yes, it is possible to reduce brightness with a change in tubes, but they would need to know more about what is in your system, (3) would first be looking at your interconnects or speaker cables, (4) wondered if you had silver cabling in your system as that can sometimes add brightness.
As far as tube microphonics, if you google “tube microphonics” you'll get plenty of hits. But you don't want any microphonic tubes in your system. I had a very microphonic tube in my preamp once and just touching the volume knob was amplified through the speakers.
No worries, it's certainly not a silly question. I'm not confident that I can answer your question about the brightness of your system to total certainty, but I can perhaps explain my earlier comments a little more clearly.
I want to make sure that my comment about the slight smearing is in the proper context. I was comparing Telefunken rib plate 12AX7 to Telefunken smooth plate 12AX7 in the signal tube position of my Rogue M180. The driver tubes were held constant with Telefunken rib plate 12AU7. The Telefunken were already my favorite tubes for detail, dynamics, speed, tone, and certainly clarity. The comparison between the smooth and rib plate is really getting down into the small details, I like either one better than anything else I've had in my system, and I could live happily with either of them and never look back.
We were listening to acoustic guitar with the rib plate 12AX7 first, then swapped it out for the smooth plate. After a few moments we realized that a little bit of information had been lost in the sound of the strings in the trailing edge of the notes. At the edges of these notes the rib plate was more convincing, the smooth plate just very slightly fuzzy. But as I mentioned before, I could live happily with the smooth plates.
I think the rib plates have a smooth sound, which to me means the sound isn't edgy. I just think rib plates provide a little more musical information around the edges of notes than the smooth. I was on another thread where the discussion included RCA tubes (which I used before moving to Telefunken) and one someone commented that Telefunkens were a little brighter sounding than RCA, so perhaps changing tubes could help you. I moved to Telefunken because I was hearing dynamics and clarity. I've never had to battle brightness in my system, and I made the change too long ago to remember that aspect of the RCA sound. But along those lines, RCA is warmer than Telefunken, and Mullard is warmer than RCA. If the other Audiogon member's comment is indeed correct, then maybe changing tubes could solve the problem of brightness in your system.
You didn't mention anything about the rest of your system other than the Focal speakers - do they have beryllium tweeters?
I asked the guys at the stereo shop today about your questions. Several comments were made, but there wasn't too much discussion, so I'll just relay the comments: (1) Focal are bright sounding speakers, (2) yes, it is possible to reduce brightness with a change in tubes, but they would need to know more about what is in your system, (3) would first be looking at your interconnects or speaker cables, (4) wondered if you had silver cabling in your system as that can sometimes add brightness.
As far as tube microphonics, if you google “tube microphonics” you'll get plenty of hits. But you don't want any microphonic tubes in your system. I had a very microphonic tube in my preamp once and just touching the volume knob was amplified through the speakers.