Using PA Speakers In A Home "Audiophile" Application!

@phusis 

I do not have my unit yet, a Pre 8, but it should be shipped any day. 

DEQX has been in business for quite a while. since 1995 I think. Their previous units were very well excepted by those who had no problems with the steep learning curve. They were limited by the slower processors that were available at the time. The newest processors are way faster and more powerful. The new units are much more user friendly and were supposed to be available 2 years ago, but covid screwed them up (processor availability), they had to switch to an even more powerful, but more expensive processor which required changes to the main circuit board. There are three units, the Pre 4, Pre 8 and LS200, a 200 watt/ch integrated. The Pre 4 has four DAC channels for mains and subwoofers and the Pre 8 has 8 DAC channels, triamp mains and subwoofers. The Pre 8 will retail for $13,000. The price of the others has not been released yet. The Pre 8 is being released first to a select group of individuals who will test the beta programming. I should have mine shortly.

All three units use the same 64 bit floating point processor. The DEQX system is unique in that it tests the near field response of the speakers before testing the room. It can determine and isolate speaker problems from room problems. Once it is set up the user has an exceptional amount of flexibility in term of adjusting the sound to taste. All units use the same subwoofer management system which again is very flexible with high resolution choices of crossover points and slopes. The processor automatically adjusts phase and timing. Presets allow for the easy selection of sonic palettes one might use for various situations  For instance you might have one preset with a Gundry Dip in it for sibilant recordings. You might have presets for different volumes (loudness correction). A favorite trick of mine is to have presets for different listening positions. The computer will adjust the timing and phase of the speakers so that any seat in the room becomes the listening position like my desk at the rear left corner of the room. All units have a phono stage which was developed with Dynavector and is supposed to be pretty good although it is high output only. I'll certainly report on that as I plan on getting a transformer to go with my MC Diamond and perhaps a few high output cartridges. My current phono stage does not have a high output section. 

Because the Pre 8 has a 4 way crossover you can turn any loudspeaker into an active speaker, each driver having it's own amplifier.  I plan on using it as a three way system, 2 channels for the low frequency transformers of the Sound Labs, two for the high frequency transformers and two for the subwoofers. The Atma-Sphere MA 2s will drive the low frequency transformers, a Bricasti M25 will drive the high frequency transformers and two QSC PL380s will drive the subwoofers. Crossover points will be at 100 Hz and 5 kHz. 

Modern pro drivers (and even ones decades old) are extremely well designed, and used within their design parameters - not least actively - will yield no effective problems with breakup modes. 

@phusis I've run into breakups in older designs (like Altec, with their aluminum diaphragms) and also in newer designs, like the JBL speakers I use for my keyboard setup. If I get over a certain volume, the speaker doesn't handle it that well (gets harsh) so it does seem like I'm setting off a breakup in the horn. 

My speakers at home use beryllium diaphragms; the first breakup is at 35kHz. 

I haven’t read the entire thread, so this might have already been mentioned.

But if one cares at all about imaging and soundstage, then pa speakers should be avoided.

I have heard dozens of pa speakers at many different price points in home systems, driven by good quality amps, and have never heard a wide, deep soundstage, with good layering, nor precise placement of musicians within it.

They all tend to project the music out into the listening space, and reproduce it in a very flat (not talking about frequency response).

Update:

- Ordered the speakers

- Buddy of mine is shipping me an old Accuphase analog active crossover unit...will try my luck with that.

@simonmoon

I have heard dozens of pa speakers at many different price points in home systems, driven by good quality amps, and have never heard a wide, deep soundstage, with good layering, nor precise placement of musicians within it.

The culprit is largely PA electronics, imo. For example, I’ve tried Crown amps on my hifi rig and the soundstage flattening is immediate. I have also observed it when trying out Mcintosh hifi amps (not meaning to offend any Mcintosh users)...the flat wall of sound with no depth, layering and nuance. Denafrips dac --> Luxman, Schiit, Yamaha hifi amps, etc should remedy that situation...is my theory for now/will know an answer in the next month.

"advanced beamforming"   What is that?