Greg Belman of Bache Audio has perfected the use of wide band drivers
(covering most of the frequency range) augmented by a woofer and (super)
tweeter - no negatives that I can hear with any of his models. My
upgraded Metro 001's are extraordinary - 4" Tang Band bamboo wide band
driver covering 500hz - 9,000 hz is superb, as is the legendary, out of
production Japanese version of the Fostex FT92-EX2 tweeter.
About seven months ago Greg Belman emailed me to say that he had figured out a crossover upgrade that would improve the sound. A couple of months ago he emailed me to say that he had tested an Eton woofer in the Metro 001 as an upgrade of the Tang Band unit currently in my speakers. The Eton produced both deeper and tighter bass but required enlarging the port. I asked if he could replace the air motion transformer tweeter with the Fostex FT96-EX2 he has used in more expensive models, and also rewire the speakers with Stage III Concepts (tweeter) and Dueland tinned copper (wideband driver and woofer). Several weeks ago I finally drove up to Brooklyn to take him the speakers. When I arrived I discovered that he had actually built and tested a prototype with the Eton and Fostex drivers that I could listen to and compare with my current speakers. Needless to say upgrading those two drivers made a significant improvement. Still breaking in but initial listening suggests significant improvements in sound quality. With the Eton woofers bass is subjectively deeper, more forceful, and more articulate. I was told by the designer that the Fostex FT96-EX2 tweeters, which extend to 33hz, would expand soundstage width and depth, and that is what I am hearing. Timbre is more realistic across all frequencies (particularly noticeable with piano), and images are more naturally fleshed out with no spotlighting. Every piece of music I've played has sounded more natural than I remembered.
About seven months ago Greg Belman emailed me to say that he had figured out a crossover upgrade that would improve the sound. A couple of months ago he emailed me to say that he had tested an Eton woofer in the Metro 001 as an upgrade of the Tang Band unit currently in my speakers. The Eton produced both deeper and tighter bass but required enlarging the port. I asked if he could replace the air motion transformer tweeter with the Fostex FT96-EX2 he has used in more expensive models, and also rewire the speakers with Stage III Concepts (tweeter) and Dueland tinned copper (wideband driver and woofer). Several weeks ago I finally drove up to Brooklyn to take him the speakers. When I arrived I discovered that he had actually built and tested a prototype with the Eton and Fostex drivers that I could listen to and compare with my current speakers. Needless to say upgrading those two drivers made a significant improvement. Still breaking in but initial listening suggests significant improvements in sound quality. With the Eton woofers bass is subjectively deeper, more forceful, and more articulate. I was told by the designer that the Fostex FT96-EX2 tweeters, which extend to 33hz, would expand soundstage width and depth, and that is what I am hearing. Timbre is more realistic across all frequencies (particularly noticeable with piano), and images are more naturally fleshed out with no spotlighting. Every piece of music I've played has sounded more natural than I remembered.