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Appreciate your honesty and integrity.

Reviewers need to make a living. And the living largely is funded by advertisements. Manufacturers advertise. That explains why we hardly see any negative reviews.

I mean Steve Guttenberg thinks Klipsch Cornwall IV is a great speaker

There are a few things not being discussed that might make a difference in how the DEQX system like my old PDC2.6 were used and how they sound.

The system offers different types of filter topologies, linear phase and more conventional Butterworth and Linkwitz-Reily alignments. When I was using it the linear phase style filters just never sounded like real world music signals to me. When I used the more conventional filters types, it sounded much better, but then there is still the internal DAC's reconstruction filters hard fixed in their design. I really prefer to see the direct impulse response of the filter, not its frequency response as it is easy to tell which it uses. A causal filter (i.e.analog filter) always starts working after the signal starts.

If you look at many of the latest DAC's out there, you will find linear phase, minimum phase and apodising filter topologies in use for the DAC reconstruction filter. Any DAC I have used recently that has the filter selection I will try them all, and all of the time do not use the linear phase selection. From research papers over 10 years ago, a non-causal filter as in linear phase confuses the ear-brain system since the signal starts before the musical transient. You can do that in a digital system, but nothing in the real world does it. So one easy way to try this is to just hear the DAC and it's filters one at a time. Wolfson, AKM, TI and ESS DAC's all have filter selections available if the mfg chooses to make them available to the user.

This goes for any DSP crossover filter design as well. I had the chance to ask about the Meridian DSP speaker design crossover once and the design is not linear phase for the reasons above.

You also have to know if the system uses an ASRC, as many of them also use a linear phase filter design as in the DCX2496. A reason that I did not like the DCX2496 as well was the DAC's.

The DSP crossovers I am using do not have linear phase filters and the DAC's have selectable filter types for that reason using the minimum phase version. They also have improved filter topologies over classical methods as that lead to lower distortion from the filters.

The fact that it is easy to do time alignment of drivers with a DSP crossover is a major plus to me. The system coherence goes up considerably. It is also easy to demo it as you can dial in none and the correct time alignment to hear it. Trying that with analog filters is very difficult as usually you can match phase at crossover frequency, but not wavefront.

Good luck with the new crossover design.

My $0.02.

Gee, I'm off line for a couple of days and I missed all sorts of good stuff. The lightning storm we had Tuesday night took out our FIOS interface, my main 48 port LAN switch, a smaller LAN switch, and my primary PC. I've been scrambling to get everything back up and running on my end, Verizon didn't show up until yesterday afternoon. Anyway, I'd like to make a few points...

- I use Linkwitz Riley filters in the DEQX
- I use Linkwitz Riley filters in the passive crossovers, same slopes
- There is no noise coming out of the DEQX, unless you play crappy 'music'.
- I'm not dropping the DEQX in favor of a passive crossover. I want to be able to use the speakers with a single amplifier, but that may end up not being the norm.
- I am not a DEQXpert. I've played around with some of its capabilities, but I prefer to try to get the most out of my system with the least amount of processing.
- While I wouldn't bet my life on it, I'm 99% sure the NOS mode on the Holo Audio DAC's are No OverSampling, it does not mean there's nothing else going on in delivering the signal out the analog connections. There is absolutely a low pass filter at all times.
- My preference is to use no equalization. In the end I may have to to get the last degree out of the system, but hopefully not.
- There are so many things that affect what and how we hear and a lot of those things change on a daily, if not hourly, basis. One of those influences, which doesn't change as quickly, is a preconceived notion of what sounds good and what does not - prejudice. I've found that this group, in particular, has a hard time listening without prejudice.
- I'd love to hear what the thread participants have to say in a true blind listening session, I suspect the results will surprise you.

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I have too much stuff - https://www.pleasebuymystuff.com

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Walt

We are talking about background noise, aka noise floor.

John Atkinson says:

Also look at the stereophile's jitter comparison between DEQX Premate and Holo Spring below . Since we are literally comparing these two gizmos, jitter could have influenced my subjective impression.

DEQX:

https://www.stereophile.com/content/all ... urements-0

Spring:

https://www.stereophile.com/content/hol ... asurements


NOS applies only to digital signals. Almost all DACs have analog output stage.


Didnt I say mids are clearer in Dhar's crossover blindly?
I am sure we can pick up presence/absence of DEQX also blindly.

I have done true blind tests on different DAC's in the past and heard a difference. Also sent a DAC to a blind test and that DAC with the minimum phase filters was selected as the best sounding of the group. YMMV