I have not heard the TPA-60s, but spent a few months with the TPA-30s. They have a stunningly gorgeous EL-34 almost SET-like harmonic richness that just makes it hard to stop listening. The 30s are neither warmer nor darker than the CJ Premier 140, although they are more transparent, dimensional, and better articulated. They work quite nicely with a 16LS (wonderful preamp). While I say they are not warmer than a Prem140, they are still on the yin side of neutral and are in no way analytic.
No problems efficiency-wise with your speakers - the TPA-30s drove my 89db 4ohm speakers with ease. I would expect the TPA-60s to have more even more heft in the lower bass than the 30s which surprised me with their power. Thor amps have excellent transformers - in fact, over build quality is top-notch and the warranty is life time if you by from a dealer.
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No problems efficiency-wise with your speakers - the TPA-30s drove my 89db 4ohm speakers with ease. I would expect the TPA-60s to have more even more heft in the lower bass than the 30s which surprised me with their power. Thor amps have excellent transformers - in fact, over build quality is top-notch and the warranty is life time if you by from a dealer.
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