Naim A5 works a treat with older, fuller toned valve gear like my Quad II's, it really does. The ONLY thing I have against it is the price today, which is ridiculous.

Naim amps have evolved from the musical 'valvey' quality of a bolt-up 250, to a harder hitting 'PA style' quality of most CB models (135 and Nait 1 excepted), to a slightly 'looser' style in the Olive range, especially when new if not twenty years down the line. The current stuff that I've heard is much better in the midrange, but 'hard clipping' and subjective bandwidth limiting from mid bass to mid treble (in my experience compared to other amps) still dates the basic design, despite more modern construction of the boards - to me at any rate.

WHEN NEW, the 42/110 was a harsh snappy terrier of a combination. 'Sweetness' didn't come into it in ANY form Richard. Yours may have been serviced to within an inch of its life and thirty odd years of use may have tamed it, but please believe me. the 42/110 (the 'point five pre is largely irrelevant here) in the first years of life was horribly scrappy and harsh unless the harshness woke up tired old speakers! Adding a High Cap to the 42.5 would bring a tad more bass in, but that was all.

The Nait 3 and related 92/90 were limp wristed and rather tame in all honesty I remember. Sold because they were 'Naim' but not because of any real ability IME. Maybe a beefed up supply and sorting the pre section may improve things, but why bother when better can be had on the used market for less...