Icon Audio LA4 MkIII Signature Line Preamplifier $3095 Review
February 24, 2022 § Leave a comment
Specifically, I was interested in trying out the 7N7 and 7AF7 loctals, 6SN7 near-equivalents via adapters, albeit with a loss in overall gain. Note that I only replaced V1 and V2, the gain stage tubes, leaving the cathode follower (V3) alone. In particular, the 7AF7 worked extremely well for the end result I was after; namely, textural sweetness galore. It wasn’t as focused or tight in the bass as the CV181, but it nicely vitalized textures when partnering solid-state designs. Neutrality or warmth—both are possible with the right 6SN7. And that is the important point about tube rolling: It allows the end user to voice the LA4 to match a particular system or sonic preference.
It would seem that David Shaw has cracked the code for preamp excellence. His classic recipe includes a 6SN7 gain stage, a tube buffer, and a tube-rectified power supply. This combination, together with excellent engineering and parts selection, makes the Icon Audio LA4 Signature into a formidable line preamp. This is one preamp I could live with happily ever after.