Well I decided to just start out by replacing the caps in the stock type C crossovers with new Sonicaps Gen I. I’m very happy with the results. The midrange and treble sizzle is now gone. There’s multiple more levels of clarity now. The soundstage is huge, and on some recordings the sound will creep along the side walls.
When I had the back panels off, I put some of the Parts Express speaker gasket tape around the back to seal up the back panel. The bass now is very tight and articulate, even on a low watt tube amp. Absolutely no “boominess” in the bass. The bass is audible down to 40 Hz, which is just fine for my tastes most of the time. I have a powered subwoofer but I hardly ever have the desire to turn it on.
These speakers just sound fantastic. They are so lively and engaging. They are my favorite speakers that I’ve ever owned. My last pair of speakers were KEF LS50’s. Those sounded good but they were boring compared to the Heresy’s. The KEF’s didn’t do well with tube amplification, they were only good with my solid state amp.
The Heresy’s are in a 13’ X 14’ room, powered by a SET amp with EL34 output tubes.
One thing I noticed when working on these is that one of the speakers is ¼” deeper than the other. The one that’s bigger uses ¾” thick motorboard vs ½” for the smaller speaker. I’m wondering if these were originally sold as single center channel speakers and then someone found two of them and passed them off as a pair. Either way, I’m not worried about it, as they sound so good.
Any comments from anyone are welcomed