Joseph Audio RM33si Signature loudspeaker Manufacturer's Comment
Editor: We are pleased to see that John Atkinson's tests now agree with ours, showing the smooth transition between woofer and midrange. We're also happy that the sensitivity result hews closer to our 83dB specification. The small remainder might well be accounted for by differences in measurement technique, weighting, and calibration.
Seasoned audiophiles know that sensitivity doesn't tell the whole story when it comes to amplifier-loudspeaker matching. Even on smaller amplifiers, the RM33si actually sounds much louder and more dynamic than one might expect. Perhaps the dynamic detail afforded by the lack of wave interference explains this. Another factor is its very amplifier-friendly 8 ohm impedance curve. RM33si owners report outstanding results with tube amplifiers as small as 20Wpc. Chip Stern, leaving no stone unturned in his full review in the October Stereophile, found that "the RM33si's offered richly dynamic, liquid soundstaging via a Simaudio I-5 70W integrated amp."
Readers should be careful when comparing sensitivity specs, since the figures quoted can be difficult to compare properly. For example, 4 ohm speakers draw twice as much current from an amplifier's 2.83V, providing a misleading impression of greater sensitivity while actually placing more stress on the amplifier. If in doubt, test a given combination for yourself.
When it comes to bass, the room has final say. In our listening room and in Chip Stern's, the RM33si delivers deep, tight bass. As Chip Stern reported in the October Stereophile, "I was never aware of the bass driver calling attention to itself; nor did it add woof or bloat to lower-midrange frequencies, or portray the deep bass in a one-note manner...;';'
An advantage of the RM33's side-mounted woofers is the extra degree of flexibility they offer for real-world listening environments. The woofers can face in or out, depending on how one wishes to excite the room. I think that if John Atkinson had had the opportunity to try the speakers with the woofers facing in, he might well have achieved the last bit of bass balance he sought.
The most telling moment comes when JA at long last puts away his meters, sits down between the RM33si's, listens, and discovers "virtually no barriers between me and the music." Welcome to the club, JA!—Jeff Joseph, Richard Modafferi, Joseph Audio