Sonist Audio Concerto 4 Speakers... performance questions

Hi All:

I am just getting my system together one piece at a time. I started with the speakers... Sonist Audio Concerto 4’s in the memorial finish. I bought them used locally because new they were way too expensive for me. I had hoped to get a pair of vintage Klipschorns but could not find a pair i could afford AND my room was a bit small for them truth be known... In any event the Sonist Concerto’s are really nice looking and have a nice sound at modest and medium loud levels... FYI, these speakers are high efficiency... sensitivity 97db; 27Hz - 40Khz.

Anyway, I have a vintage amp in great shape (I think). It’s a budget amp... a Superscope A225... not a common size... but rated at 15 watts per channel; 20-30k KHz; distortion < .5% at 4W; Signal/Noise 70 DB (not so great). Superscope of course had a relationship with Marantz.

Overall, the speakers are very nice sounding... perhaps a little light on the base... but that was not unexpected. My concern is that they perform well up to 90 db... then there is noticeable distortion. This is achieved with the volume at about 40% max... so.. most likely 6 or 7 watts assuming the dial turn is proportional to watts.

So, I am wondering if this is just the limits of the speakers.. or if i may have an amplifier issue (both channels behave identically). To clarify, there is no popping per se... not even cracking... just a distortion.. muffled rumbling/vibration... not a happy sound so i back right off.

My cables are not loose in any way but are just general consumer grade... I am going to upgrade those tomorrow... any thoughts appreciated on my situation


Jeff in Western Michigan
You need MORE power! 15 watts are not enough with those speakers! Musical peaks can require 10X the average power level to avoid clipping distortion. Get an integrated amp with 100+ watts - an NAD is an easy recommendation!
Thx for the advice.. found a amp calculator online to punch in the specs and you are 100% correct I do need more power... am considering a Vidar fro  Schiit... saw it when i was reviewing DAC options.. 100 watts per channel and can be used in a balanced mono block setup in the future by buying a second one should the need arise. It's listing for 699... would also need a preamp... they sell a simple passive one for $49  plus other options.. hmmm interesting