are there 2-ways that go down flat to around 40?

Maggie 1.6 have been measured to about 36hz.

I just heard the ProAc Studio 125 this afternoon and I believe they did, with authority.

My old avalons did- the model Eclipse went to high 30's in a two way sealed design.

The Thiel 1.6 is flat to about 40 in my room, then falls off a cliff. The ProAc 2.5 has usable bass to the mid-20's in my room.

Troublesome topic. The ProAc 2.0 and 2.5 seem to. The Totem Mani 2 also.

But, so does the $300 AE Aegis One, and there's the problem. Most small speakers that give a robust response at 40 hz, or below, are not putting out a true 40 hz signal. The spl meter will react to what comes out and show a strong response, but the sound reproduced by the speaker includes a lot of distortion and doubling and the net effect is usually something closer to 60hz. Almost all speakers have a lot of distortion in the bass. Go to Soundstage.com and look at the measurements accompanying the archived reviews of loudspeakers to see what I mean. Many highly regarded speakers have distortion and noise a mere 30-40 db below a 90 db signal.

What's the value of 40hz anyway? I'd rather have the perfectly accurate and undistorted 50hz reproduced by my Harbeths (down maybe 6db at 40).