Pre/Power Amplifiers

Almost every new tube amp seems equipped with 'gherkin'-shaped KT150s these days but the SQ-N150's diminutive form factor demands tubes of a similar stature. Hence Luxman's choice of stalwart EL84 pentodes, one pair per channel running in ultralinear guise to deliver just 2x12W across any speaker load between 8 and 4ohm.

There is only one tap on Luxman's output transformer and this is configured for 6ohm – hence Luxman's 10W/6ohm power rating – but this does not mean its frequency response is as reliably 'flat' as its power output. In practice, the 6ohm tap offers a 0.6ohm output impedance, rising to 0.8ohm/20kHz and up to 1.55ohm at the 60kHz transformer resonance [see dashed orange trace, inset Graph]. The impact on high frequency response is also illustrated [no speaker load, grey trace; 8ohm load, black; 4ohm red; 2ohm, blue; 1ohm, green]. PM