benchmark and apogee

Not to make too much of a generalization, however it seems that folks with "metal dome" tweeters have issue with the Benchmark. I have the Benchmark DAC PRE I really like but my speakers are Harbeth M40 (soft dome) that are on the warm side. I had B&W N804 a few years ago and they always preferred a less analytical DAC. The Classe DAC I had worked well with the B&W's.

Frank_sm - My Benchmark was on the bright/brassy side with aluminum dome tweeter. After replacing with soft dome tweeter it is way better. Tweeter (Morel Supreme 110) is a little on the hot side but also much cleaner (underhung motor).

That is a nice tweeter but it rings (like most metal drivers) - see the Cumulative spectral decay at 9000 Hz. Of course a speaker designer will try to notch filter this problem out and being a single frequency that is not hard to do - although at elevated SPL's as the tweet warms up (impedance rises) and ringing becomes more excited then the notch may not be as effective or as precisely tuned. Some metal or ceramic drivers have rubber dots on them to try to correct this or even some damping paint. Some have elaborate arrangements with the "backwave". There is no doubt these type drivers get an impressive frequency response but resonance such as you see here is never a good thing.

Shadorne:

Thanks. It shows as one hot high sibilant - audible at first but much better now (but still there). I will think of notch filter at 9kHz. In spite of that it is still a lot cleaner than $25 Vifa it replaced.

I would not do this again - it is way to complicated and requires equipment (and experience) I don't have (not to mention room acoustics). I updated crossover components and was planning to continue further (Dueland resistors and capacitors) but it's another $400. I want to listen to new Revel Studios 2 and possibly get used one within few years.

I will think of notch filter at 9kHz.

Most speakers with metal or ceramic drivers have notch filters built into the crossovers - the frequency, depth and width (Q) of the filter need to be chosen carefully though. You would probably need to be able to perform waterfall plots to make appropriate adjustments.