Conrad Johnson Amp with ESL9s

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Jan 14, 2021
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Long time lurker... First post and a question about my set-up and amp suitability, hoping someone can help.

I have a home cinema and listening room combined, with a pair of Classic 9s up front which are driven by a Conrad Johnson Premier 11 power amp.

I’ve never really had any issues until recently having upgraded my cinema processor to a Lyngdorf MP-40 and whilst running room perfect calibration I noticed a little distortion. I don’t run my cinema very loud, but the calibration processes required the volume to be turned up a little higher than normal and that’s when I noticed some distortion and the little red LEDs on the power amp were flashing. its possibly a question for members in the Conrad Johnson forum, but I‘m wondering if I should be considering upgrading to a higher powered amp anyway? I’m now concerned that I’m already getting close to the limits with this amp and wondering if there much headroom left. Here are the specs, what do you guys think?

Power: 70 watts RMS per channel.
Sensitivity: 950 mv to full power.
Small Signal Distortion: Less than .1% at midband.
Phase: Phase correct (non-inverting).
Frequency response: 20Hz to 20KHz +0, -.5dB Hum and noise: 98dB below full power output.
Input impedance: 100K ohms.

If I were to upgrade to another tube amp what minimum specs should I be looking at to safely run the ESL9s.