Yesterday, I spent sometime at Dave's. My take on his system:
Couple of us were concerned how well a 7" ribbon tweeter integrates in MTM configuration. It did integrate very well, there were no anomalies from the listening position.
The MTM system is very good overall. It images very well, vocals are very good and the highs are detailed and sweet.
In his system, the comparison between active and passive configuration is not valid as they are differently configured. In the active configuration, DEQX processor is used as active crossover. DEQX is limited to 96kHz bandwidth. So, Dave is feeding 96kHz upsampled material from foobar to DEQX, which divides the frequency ranges into highs and lows in digital domain and sends the data to 2 Spring DACs via SPDIF.
Holo Spring DACs are very good. We talked about the DAC and switched to passive crossover. This time, at my request Dave configured foobar to upsample to 384kHz and feed one Spring DAC via USB. The difference was immediately noticeable. Background became silent. We did not do detail comparison, but the obviously evident background noise is enough to convince me that using DEQX is not a good idea in a quality audio system. It was limiting the virtues of Spring DAC.
I have been using the DEQX for many years and it is completely silent. Can't understand why Dave's had noise.Then Dave switched the passive crossovers and the mids/vocals became cleaner and the bass seemed to become tighter. Later Dave revealed this crossover is designed by Dhar where he fixed 1kHz bump and treble. Dhar did a very good job with the crossover.
When I use the subjective terms like silent, cleaner etc., they do not indicate an issue with the MTM speakers and those are readily noticeable. Very often we realize the deficiencies by their sudden absence.
In my opinion, DEQX should be dumped and pipe highest bandwidth digital stream to Spring Directly. I believe Spring Gen 1 is capable of 1.536mHz bandwidth.
Active system can still be implemented by building a passive line level crossover (PLLXO) between preamp and power amps.
https://www.t-linespeakers.org/tech/fil ... eHLxo.htmlOverall, very good MTM speaks.