Room correction - what device works best?

Almarg,

What a great post. Great synthesis of the potential of a DEQX.

Are you planning to go active with your speakers, getting rid of the passive crossovers?

You might recall I thought about the DEQX HDP-4 (at the time) and eventually opted for Acourate. Yet my end destination seems to be very aligned with yours. I opted to build a system around this concept and will build my own speakers, multi-amp, use active digital crossovers and get a time aligned, linearized, room corrected system.

I am technically inclined, but certainly less experienced/knowledgeable than you. It would be great for me to be able to bounce ideas/questions with you as you also go through this process. Such a fun project!

Thanks very much, Lewinski. Yes, I've followed the posts and threads related to your project, and I'm happy to comment whenever I can contribute anything meaningful.

As you realize, the three independently configurable pairs of output channels provided by the HDP-4 and HDP-5 can support active biamping or triamping, but I have no plans to do that. In part because doing so would entail what to me would be desecration of the fine craftsmanship that went into the construction of my speakers; in part because the innards of my speakers are not readily accessible as practical matter; and in part because in the absence of any knowledge of the design of the speaker's internal crossover I would by no means rule out the possibility that the sonic results would end up being a downgrade rather than an upgrade. And of course there would be a lot of expense for additional amplification.

Based in part on listening comparisons with my Stax electrostatic headphones I'm pretty much convinced that the weak link in my system is presently some combination of room effects (which I can't address with conventional room treatments since it is my living room), and speaker time incoherence. So I'm just looking for some modest improvement in those areas, and in the process perhaps I'll also benefit from substitution of the DEQX for my preamp, and from utilization of the DEQX's DAC function in place of the one that's internal to my CDP.

Yes, as you indicated these are fun projects, and also highly educational. Those are the main reasons I am intending to do it all myself rather than utilizing the DEQXpert or equivalent services. And if it takes a month or even two, I'm fine with that.

Best regards, and continued good luck with your project.
-- Al

Using two subs is the best way to get a flat frequency response, unless the room is too small to allow the main speakers to be brought well into the room. DEQX will solve the timing and frequency problems of integrating subs with main speakers.

Al,

Yes, your speakers are truly of fine craftmanship. I've never heard them, but always found them very appealing from what I read.

Are you sure the DEQX can achieve time alignment among the drivers if you are to keep the passive crossovers in there? My understanding is the time alignment is done between pairs of channels, at the crossover points, through linear phase crossovers. Hence the need for actively amping. Maybe DEQX is different, but I think I did exchange with a user about this. At least on Acourate, I know the system can't time align if it only sees two channels as it can't delay part of the signal within a channel. This is why this decision has been so difficult to make. My system will need to change almost completely.

Thru DEQX time alignment can be achieved with speakers with passive crossovers. As it measures the response to test tones, it digitally adjusts the arrival times of all frequencies measured. So differences between drivers as well as any time arrival differences that might be produced by a particular driver itself.