Flat Anechoic Measured Frequency Response Speakers

It's amazing to see that some of my favorite speakers tend to have similar frequency response: Dynaudio and Thiel. The impedeance plot is very helpful in matching amp.

Coincident speaker definitely is very friendly toward SET amp while Thiel and Dynaudio will rquire lots of low impedance driving capability.

Shadorne,

The ATC has a very flat response. Do you find that flat responses sometimes limit the 3rd dimension to the soundstage? In other words, do you find it is more like a two dimensional picture than a three dimensional picture depth-wise?

Thanks.

Looking at the measurements for several speakers I know well, it surprises me how similar many of them are. For example, Dynaudio C1 and Thiel 2.4 look quite similar (and both very flat) to my uneducated eye, although they don't sound the same. Interesting to look at something like the Reference 3a MM decapo, which seems to measure pretty horribly. Or the Silverline Sonatina, which has a big midrange dip. Even the Watt/Puppy is a bit ragged. How important is this, I wonder.

Would love to see measurements for some models of Harbeth.

The ATC has a very flat response. Do you find that flat responses sometimes limit the 3rd dimension to the soundstage? In other words, do you find it is more like a two dimensional picture than a three dimensional picture depth-wise?

No not at all. A flat "power response" without the usual treble and bass boost can sound extremely natural and is hard to distinguish from live or real instruments. The vast majority of speakers have a strong off axis response in the bass and treble with a dip in the midrange. Sometimes called the "BBC dip", this has become so popular in consumer speakers since the 80's that a flat power response is rare and is usually interpreted as "forward" or "harsh".

There is a strong correlation to soundstage (although most depends on the recording)...there is a tendency for instruments to sound closer as if they are in the room with you - so you could argue that there is less depth with this pattern - conversely you could argue that other speakers will never reach as forward into the room or close to the listener forever relagated to sounding as if you are at the first balcony....so I think the soundstage moves forwards somewhat but is no less or more compressed than speakers with a BBC dip.