@yogiboy Do you have the older 60 watt Quicksilvers? Or the new ones?+1 @yogiboy
Agree. This is an important question for @majorc to answer to first.
@majorc
FYI, my local dealer who’s carried Quicksilver amps and Eminent Technology speakers since the 90s shared to pass along to you today, quote: "the older mono sixties with smaller transformers running EL34 output tubes are power limited to effectively drive and power the lower efficiency 82db sensitivity EMT LFT8b speakers." He’s tried several amps with your speakers over the past few decades.
He also shared, The "latest design QS Mono 60s with the LARGER transformers and KT88s -OR- the QS Mono 120s with KT150 tubes -OR- a good 100wpc solid state amplifier would be a much better choice to drive your LFT8b speakers". He also shared a good matching preamplifier for a proper amp(s) is highly recommended.
Hope this helps...