[bside123]

Hi: I recently acquired a Vacuum Tube Logic TL 5.5 preamp. It utilizes 6 tubes: (2) x 12AX7 and (4) x 12AT7. In trying to get to know this preamp, I've rolled several different combinations of tubes, BUT I cannot get the highs to sound smooth and "sparkly."

The preamp images well, has air and texture and a liquid sounding mid-range, good bass slam, etc., but the highs are driving me nuts  ... sharp, edgy and too much grain. The highs can really get in your face... glare.

I've used various combinations Mullard, Telefunken, Mazda and Brimar -  all known for various degrees of "smoothness." Right now, my set up is: (2) Mullard 12AX7A and (4) Brimar 6060 (T-Logo). All the tubes I've tired have been matched.

Any thoughts or experiences with the VTL 5.5 out there? Mods, Tube Combinations, Equipment Matching? Thanks.

[bside123]

For VTL owners/users, or other tube guys, no thoughts on this? Any input would be appreciated. 

[Sarmck]

Hi bside123,

The combination of tubes I finally settled on for the TL 5.5 were 2 x Sovtek 12AX7LPS and 4 x Sylvania Gold Brand 6201 tubes.  This seemed to bring the sparkle and shimmer of the highs out, yet bring everything together in the sound stage with balance allowing long listening sessions without fatigue.

I'm sure that you've read the VTL TL 5.5 review in ETM:
http://www.enjoythemusic.com/magazine/equipment/0602/vtltl55.htm
where Wayne suggests: "NOTE: After a bit of experimenting, I find that CD sound improves when I connect the player to one of the tape inputs activated by a front-panel toggle switch, rather than connecting it normally so that the signal passes through the Source Select switch. The difference is not great, but it is audible."  That's if your not running something through the tape loop already.

Hope that helps you out a little,
Ron

[RadioWonder]

I use NOS Tungsram ECC82 in my older VTL Super Deluxe pre-amp... Great tube...