Bow- You are bound to have a slightly different suggestion from every poster. You have obviously attempted to assemble a high quality system and have given thought to each choice. None of the suggestions above, or mine, are meant to belittle your efforts. I agree with others that you have a couple of components that may contribute too much in this area when combined in your system.
My first recommendation is a thorough evaluation of your room since alterations can be accomplished relatively easily. Could there be sidewall reflections or hard, reflective surfaces on any wall contributing to the glare? Have a friend/family member walk with a mirror along the sidewalls while you're seated in the listening location. If you can see the speaker in the mirror, this is an area that could be contributing to early reflections. Also, I strongly suggest playing with speaker tilt as well as toe-in. Changing the tilt of the speaker can have significant effects upon the tonality.
Next, consider using the Sakura OTA cable kit. It isn't well known (yet), and is relatively inexpensive. It provides enough cable and IC terminations for three pairs of interconnects and at least one set of speaker wire, all for around $600. Don't let the price fool you. I currently have over $10K in speaker cables and IC, and this stuff is equal to or better in many areas. One of it's strengths is a marked reduction in midrange strain or glare, yet offers marvelous detail, tonality and palpability. At the price, you can't go wrong.
Next, I would be experimenting with different sets of NOS tubes for the SF equipment. This can have dramatic effects on the sound, but can become expensive.
All other suggestions that I offer will effect the sound but aren't targeted for just glare reduction. I'd offer, though my preference is for tube amps, to investigate into a better tube pre-amp. Your system appears to be at a crossover point between good to very good. Having owned this piece, I would recommend seeking a higher standard. Some may hear this as a putdown of the SFL1 Sig, but it isn't intended as such. It is a fine unit and well built, but sonically, there are better with less contribution to your current problems. (With modifications, it can be significantly improved, but most people tend to want only stock equipment). This change will likely not be inexpensive. You might consider an integrated amp approach which would eliminate the need for a separate pre-amp and interconnects and power cords! There are some exceptional products available which might make this approach more cost effective. However, this can require a complete re-evaluation of the speaker/amp relationship.
Good luck with your quest. As always, Just my .02.
My first recommendation is a thorough evaluation of your room since alterations can be accomplished relatively easily. Could there be sidewall reflections or hard, reflective surfaces on any wall contributing to the glare? Have a friend/family member walk with a mirror along the sidewalls while you're seated in the listening location. If you can see the speaker in the mirror, this is an area that could be contributing to early reflections. Also, I strongly suggest playing with speaker tilt as well as toe-in. Changing the tilt of the speaker can have significant effects upon the tonality.
Next, consider using the Sakura OTA cable kit. It isn't well known (yet), and is relatively inexpensive. It provides enough cable and IC terminations for three pairs of interconnects and at least one set of speaker wire, all for around $600. Don't let the price fool you. I currently have over $10K in speaker cables and IC, and this stuff is equal to or better in many areas. One of it's strengths is a marked reduction in midrange strain or glare, yet offers marvelous detail, tonality and palpability. At the price, you can't go wrong.
Next, I would be experimenting with different sets of NOS tubes for the SF equipment. This can have dramatic effects on the sound, but can become expensive.
All other suggestions that I offer will effect the sound but aren't targeted for just glare reduction. I'd offer, though my preference is for tube amps, to investigate into a better tube pre-amp. Your system appears to be at a crossover point between good to very good. Having owned this piece, I would recommend seeking a higher standard. Some may hear this as a putdown of the SFL1 Sig, but it isn't intended as such. It is a fine unit and well built, but sonically, there are better with less contribution to your current problems. (With modifications, it can be significantly improved, but most people tend to want only stock equipment). This change will likely not be inexpensive. You might consider an integrated amp approach which would eliminate the need for a separate pre-amp and interconnects and power cords! There are some exceptional products available which might make this approach more cost effective. However, this can require a complete re-evaluation of the speaker/amp relationship.
Good luck with your quest. As always, Just my .02.