Thanks for the more comprehensive explanation on the DBX. Rives Audio has a similar system (PARC) to flatten the low frequency response. However, they strongly recommend to first try and correct the problem by experimenting with room placement. The 80 Hz peak I was seeing in my setup was caused by a room mode and it got remedied by moving the speakers 2’ from the rear wall, as opposed to the original distance of 13”.

From what I’ve read, the M80’s seem to be brighter and more difficult with placement than the M60’s. Although I also prefer speakers that are more on the bright/revealing side (having loved NHT 3.3’s and 2.9’s I auditioned in the late 90’s), sibilant/fatiguing is another thing. I found that the resistors lowered the level of the tweeters without really getting rid of the sibilant ssss’ which the wool felt taped to the tweeter mounting plate did a better job with (I use both).

I know that some of the sibilance is also due to the CD changer which is currently the weakest link of the system. On that note I’d like to mention that the Sony CDP-CX455 400 disk changer sounds better than the CDP-CX355 300 disk changer (I have both). This surprised me because I thought that both being current models of the same line would only differ in capacity. I originally tried to attack the sibilance issue by using an external DAC (I tried the Musical Fidelity A324) connected via optical cable. Although the highs sounded better through the external DAC, the fact that we have 3 CD changers meant that we also needed an optical switch to connect them all to the DAC. Unfortunately, through the optical switch the sound was degraded and virtually negated the advantage of having an external DAC. I know what you might think: optical cables/switches only transmit 0’s and 1’s in the form of light pulses, how can they have an adverse effect on the sound? Well, hearing is believing, so we couldn’t justify the $750 price tag of the DAC and it went back. Then I read on these boards about the resistors… This audiophile stuff is such a vice! I’m not even claiming to be one but the bug has bit me.