Want more high frequency extension


I like my current set up, however, I find the high frequency extension to be lacking. Any thoughts on how I can achieve more extension? I was thinking one of two areas, preamp change or tube rolling in my amps.

I currently have an Audible Illusions L-1 with Bugle Boy 6922 tubes. I was thinking of maybe trying a passive pre like a Placette or trying a SS pre. thoughts?

Alternately, I was thinking of rolling out the stock tubes in the Six Pac's. Right now they are Rubey Tubes El34's for the output tubes, Electro Harmonix EL84EH for the current source, and Westinghouse 12BZ7 for the gain/phase inverter. The amps will also take KT-66, KT-88, 6550C, KT90 and KT-99 in the output stage and 12AY7 and 12AX7 for gain/phase. Any tube replacement that will provide more extension?

Thank you in advance
mattybumpkin
Try substituting another preamp.The AIs are good,but high frequency reproduction is not their forte,Transcendent GG,Placette passive/active,First Sound Deluxe, even a CJ.Arrange some home auditions with a cooperative dealer.Happy hunting.
Mattybumpkin...If amplification is the problem I really think the power amp is probably the place to look. EL34 and KT88 tubes are pentodes, and I bet that there is local feedback from the transformer to the output tubes. "Zero Feedback" probably refers to "global" feedback.

I suggest that you try a SS amp, or one of a few tube amps that are flat to 100KHz (but these are not low feedback).

For some things, 39 is over the hill.
Construct a time machine and go back to your teens; preferably female.
Buy the Rives audio test-tone CD and run some upper end tests. You'll (probably) cry yourself to sleep for a week.
Check out conversations with your parents; that's what your hearing is going to turn into.
Get your ears cleaned professionaly once a year.
Unless your age starts with a 1 or maybe a 2, 15kHZ is probably a long distant memory. And 10k ain't that far off.
Most of the above advice is useless, unless you first determine what *your hearing is capable of, before what your *system is capable of.