Digital Processor Reviews

I would think your room has to be OK for it to be able to produce a decent room curve to begin with.

Your idea of continuing to tweak your room while you have the toy is genius.

It would be cool to have a "mother module" to use to set the room, and then a much less expensive "servant module" or chip that could talk to your DAC that you could then plug in to keep 1-3 curves while allowing the mother ship to continue her sonic journey.

Nice to see audiophilia using (at least not afraid of) EQ and finding benefit in "room correction" techniques.

So, basically, from a technical perspective is this performing 2-channel 35-band parametric EQ (settings up to 50kHz)?

Is there any time-domain correction being done when fed with room information (doesn't look like it?)?

Wow, what a great addition that would be.

Something very unexpected here - the flat response curve is incredibly flat, I would estimate -3dB +1dB. This is a flatter response than most professional studios achieve, even the best. It’s totally flat 30Hz to 90Hz, which is absolutely remarkable. This Is very special room.

I've been listening seriously and buying good gear for over 40 years, and I firmly believe that the effects of some "tweaks" CAN be measured while we haven't yet discovered how to measure other audible tweak results. However, I also believe that many tweaks are placebos. Is the DG-68 sufficiently sensitive to identify/quantify/adapt to some of the supposed "night-and-day" effects of some of these tweaks?

I wonder how this unit's results would compare to some of the other (much less expensive) room correction systems, e.g., Audyssey, ARC, Trinnov.

Love to have this thing, but I would have liked to have heard the comparison of what Rossini Ring/Dac was like from the Accuphase's digital outputs compared to it's own ESS dac (never been a lover of the ESS converters). (was it done???)

Cheers George

Back in the late 90s I bought a Sigtech for $7,300 which, in addition to room EQ, performed time alignment, cancellation of late arriving ceiling, floor and wall reflections out to 50mS, and had the ability to compensate for spectral build up [from room corners, etc].
I owned a pair of Dunlavy Vs at the time, later upgrading to the SC VI.
Since the Dunlavy's are all time-aligned to begin with, as expected, the impulse response did not visually change after a correction filter was applied. I too found it easy to get caught up in jumping from correction filter to correction filter and being distracted from the music. The Dunlavy recommended listening position was against the long wall so the speakers could be placed with a wide listening angle - up to 120 degrees! [per the manual] and obtain the smoothest bass response by eliminating room nulls. I liked mine at about 100 degrees as there was a level of psychoacoustic wonder at hearing a phantom center image with the speakers 12 feet apart while still presenting a reasonably proportioned soundstage. I later learned from the SigTech measurements, that with the listening position against the rear wall, the room buildup in the bass was enormous! A significant contribution in my system that the Sigtech made I felt, was ameliorating the room build up against the rear wall as well as smoothing a 12dB delta from 30hz to 90hz - I suspect from the interactions between the bass drivers positioned at the floor and the top of the cabinet. The low frequency measurements of my speakers from Dunlavy's very large anechoic chamber showed a similar 12dB peak to null although at slightly different frequencies from my room. Also, I recall, not all of that 12dB difference could be flattened as you wouldn't want to add unprecedented gain at high listening levels at the null which could blow the drivers. In a nutshell, in my room, taming the bass [overhang] was a significant factor in arriving at more transparency and I felt that manually treating the room [absorption in my case] for first sidewall reflections worked better than relying on the Sigtech's ability to cancel them out - even though these reflections were eliminated on the filtered impulse response. The measurement capability of these reflections was instrumental in confirming the before and after effects of midrange smearing that was eliminated after applying absorption from first reflections. I was not successful attempting to fix bass problems with corner traps.
The 2khz -3dB/octave rolloff was the recommended default filter. The flat filter sounded dry and sterile and was not pleasurable to listen to although I look back and wonder if part of the reason was that the recommended rolloff starting at 2khz may have masked the sub-par 90s digital in my system [Wadia 270 Transport/27ix DAC]. For what it's worth...

I recall setting up our Listening Rooms at Esoteric Audio in the 1980s.

We ended up with a Semi-Anechoic type result that needed the Largest Mono Amps pushing thick MH-750 Music Hose Speaker Cabling.

Do our brains re-calibrate room accoustics for us ( to some extent ) ?

I suspect that Room Problems are exasperated by Loudspeakers with too-powerful Bass circuits and no balancing electronic circuits..

B&O make that gigantic Beolab 90 that features built-in Room Correction.

Full Range Loudspeaker Manufacturers should include some sort of Bass management system as an included component. ( Genelec )

Leaving Accoustic Engineering in the hands of purchasing Consumers seems irresponsible.

Accuphase Gear is Georgous

Tony in Venice Florida

I think you would be a very cool neighbor to have Tony :)
I enjoy your industry stories and commentaries from your experiences.