Description

This is the current iteration of my dedicated listening room, originally built nearly 25 years ago. The suspended hardwood floor and thick plaster and lathe ceiling are 100+ year old originals. The walls were purpose built DIY using room-within-a-room airtight construction, Roxul mineral wool in the wall cavity, and 5/8" drywall over 5/8" OSB on the inner walls. The floor and ceiling joist spaces are filled with blown-in fiberglass pink. Dedicated HVAC and air exchange via a whisper quiet Mitsubishi Mr Slim mini-split and a hospital grade ERV. AV system electrical is provided by three dedicated 20a lines with isolated grounds and identical length 10/3 BX armored wire feeds.

The gear contained within along with the extensive room treatments represent a decade long quest to successfully add and integrate multi-channel music and cinema to a room that was originally intended for stereo music only. After a series of failed attempts to achieve acceptable 2-ch sound quality by running stereo sources into high-end Meridian multi-channel pre-processors and active DSP loudspeakers, I changed strategies. I created two entirely independent source, pre-amplification, and bass management signal chains which share only the L & R front speakers and the subwoofer array.

The two independent system signal chains are kept electrically separate with a pair of handy balanced stereo ARX 12v relay triggered switch boxes hidden behind the rack. The 2-ch system is the default but when I switch on the Anthem pre-pro, the ARX switch boxes automatically re-task the stereo pair of active speakers and the subwoofers to M-ch duty.

2.1-ch sound and then 5.1.4 M-ch music sound quality were prioritized in that order with loudspeaker choice along with loudspeaker & MLP placement. The LCR speaker trio and MLP are five or more feet from front and rear walls in the 20.5'x14'x11' room. When compared with good stereo room acoustic treatment practice, the treatments may appear excessive. However the additional sidewall broadband traps each address the primary reflection of a specific loudspeaker and there are five rather than two loudspeakers at bed level. Floor to ceiling stacks of ASC TubeTraps have their integral diffusers oriented so as to only absorb bass frequencies. Finally the proliferation of DIY poly-cylindrical diffusers along with the rear wall SevenAudio 1D fractal diffuser eliminate slap echo high-up on my walls and help to create a spacious and unexpectedly huge stereo soundfield. Stereo playback often offers soundstage depth, width, and even height which exceed the physical dimensions of the front half of the room.

Thanks to the five identical bed loudspeakers and room treatments, DVD-A and SACD M-ch music recordings and movie soundtracks manage to create highly specific virtual sound sources to the sides as well as front and rear. Media with great Atmos and DTS-X immersive audio is laugh-out-loud fun with SFX coming at you from all points. The four sealed Seaton Submersive subwoofers, each with a pair of opposed 15" drivers and 2400 watts, benefit from substantial room-gain due to my rigid wall construction. With the smoothing provided by the floor-to-ceilng 16" and 20" TubeTraps and a couple bands of parametric EQ, the system's REW measured low frequency performance extends below 10Hz before rolling off. So the subwoofers definitely contribute to the sense of space with recordings performed in large live venues.

Finally it's worth discussing the video performance. The best possible M-ch sonics are achieved with an identical vertically oriented LCR loudspeaker trio. This necessitates an acoustically transparent projection screen like commercial theaters. I chose the woven S-SE 4K Enlightor screen as it had the absolute minimum sonic compromise when dropped for viewing and an awesome moire-free picture. Unlike perforated plastic screen materials, there is no audible combing effect when the left and right speakers are toed in to achieve an optimal soundstage- just a barely perceptible 1dB broadband mid and high frequency roll-off. Of course for music listening, the motorized screen is retracted up out of the way for zero sonic compromise. When listening to multi-channel music using the Oppo player, I have a tiny 15" 4k flat-screen display adjacent the gear rack to aid in on-screen menu navigation. At just a 9-1/2' viewing distance the picture on our 105" AT screen is a perfect match for the big, ballsy sounding surround audio. For 2:35-2.4:1 aspect ratio movies, the huge Isco anamorphic lens ensures maximum resolution and brightness from our faux 4K JVC projector.

So there you have it, the story of how I managed to successfully refute the naysayers that claim you can't integrate high sound quality stereo and home theater without compromise. Feel free to constructively comment or ask any questions you have. Be well.
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Room Details

Dimensions: 20’ × 14’  Medium
Ceiling: 11’


Components Toggle details

    • Jay's Audio CDT2 Mk3 Transport
    (February 2022 addenda) Performed the Mk2-to-Mk3 update, replacing the main and display circuit boards.
    • PS Audio DirectStream DAC (modded)
    (May 2022 addenda) Over the past year I've retrofit a pair of higher quality Edcor signal transformers in the analog output stage as well as adding a 12v/4a outboard linear power supply to independently power the analog output stage. The sonic end result of these two tweaks was well worthwhile and approved by the DAC's designer.
    • Oracle Audio Technologies Delphi mkVI Reference w/ Turbo PS
    • SME V tonearm
    • Benz Micro LP-S MR moving coil cartridge
    • Foundation Research V5 Phono Stage
    • Coincident Speaker Technology Statement Linestage Mk II
    • JL Audio CR-1 Subwoofer Crossover
    • (2x) ARX RS-1 12v Remote XLR Switchboxes for 2-ch or M-ch signal chain switching
    • Oppo UDP203 Universal Disc Player w/ extensive Oppomod modifications
    • Apple TV 4k AV Streamer
    • Anthem AVM60 HT Pre-Processor
    • (2x or 5x) ATC SCM20 ASL Pro MkII active monitors on Skylan Stands
    • (2x) Meridian 557 Power Amplifiers for Atmos overhead channels
    • (4x) ATC SCM12i Pro monitors on K&M ceiling mounts for Atmos
    • DSPeaker Anti-mode 2.0 Dual Core subwoofer delay and modal EQ
    • (4x) Seaton Sound Submersive HP Subwoofers
    • JVC DLA-X990R Projector
    • ISCO 3L Anamorphic Lens on motorized sled
    • Seymour-Screen Excellence EN4k acoustically transparent motorized 105" 2.37:1 "Superscope" screen
    • Balanced Power Technologies BP-2 balanced power conditioner
    • (4x) Balanced Power Technologies BP-3.5 Sig Ultra balanced power conditioners
    (Oct 2021 addenda) I added a 2nd pair of these in 2021 so I could assign one unit solely to each pair of the Seaton Submersive HP subs with their noisy Class D amplifiers and switching power supplies at each end of the room. Then the remaining two provide the power to Class AB loudspeaker amplification at each end of the room.
    • (11x) Foundation Research LC-1 power conditioner/cords
    • (7x) Foundation Research LC-2 power conditioner/cords
    • Furutech Reference III wire loom for 2-ch components
    • Grimm Audio TPR/Xhadow XLR custom wire loom for M-ch components
    • Mogami 2534/Vampire XLR custom wire loom for subwoofer array
    • (5x) Furutech DPS4.1 custom power cords for B-P-T power conditioners
    (October 2021 addenda) bought two more to power an additional pair of B-P-T Sig Ultra balanced power conditioners added at the same time.
    • DIY Thinwall welded stainless, carbon composite, and Corian equipment rack
    Built entirely to my specifications. Each component is individually leveled and then isolated by it's own sandbox. Stainless rack frame built by welder and metal worker extraordinaire, Hugh Black of True North Cycles. Carbon composite top shelf fabricated by aviation and sport specialist, Apex Composites. Individual Corian sandbox platforms fabricated by a local kitchen counter top company.

    All components interface to their respective sandbox with BDR cones and pucks/pits.
    • IsoAcoustics Gaia II isolation feet for all 5 bed loudspeakers
    • SVS Soundpath Isolation Feet for all 4 subwoofers

Comments 18

Showing all comments by vincehoffman.

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Owner
Added new pics to reflect several major room treatment strategy updates along with a couple of minor gear updates.

vincehoffman

Owner
Wow! You have the eyes of a Hawk @mytthor ! First thanks for the kind words. The aftermarket record clamp on my Delphi is the Oracle version of the Black Diamond Racing record clamp. I don't think BDR makes record clamps anymore but way back when there was a VPI compatible version too. Its pretty "hair shirt" in use as it's comprised of two separate pieces and you must re-tune your suspension to accommodate its weight. However, it brings a little additional warmth and clarity to vinyl replay vs the stock Oracle clamp.

As for the wall mount turntable stand, well the now discontinued Grand Prix Audio Brooklands is a work of art and a perfect aesthetic match to the Oracle. Here is a link to the "somewhat involved" install of the wall mount. https://www.canuckaudiomart.com/forum/viewtopic.php?f=4&t=56074

vincehoffman

Owner
Great question @caphill. Over the 40+ years I've been keenly participating in this hobby, I've owned and enjoyed good-to-great examples of both passive and active loudspeakers, big and small, in both floor-standing and stand-mount versions. These are the first ATCs I've actually owned but I've heard both well driven passive ATC models and their active brethren on many prior occasions over several decades. Both versions could sound great but the actives were consistently superior regardless of how expensive a power amp drove the passive version. I've always admired the truthful sound quality the brand consistently exhibited so my eventually owning them while a long time coming, was unsurprising.

When first built nearly 25 years ago, my dedicated room began as a stereo playback space. It sported a tubed signal path and massive ARC tubed mono-blocks (8x 6550 output tubes/ch) driving a pair of Merlin VSM-M loudspeakers which I dearly loved. When the decision was made to go multi-channel in this room a decade later, there was no practical way to incorporate five channels of the same in a 20x14' room. There wasn't the physical space and the waste heat from the vacuum tubes present in the stereo set-up was already barely tolerable- LOL!

Great active loudspeakers provided a perfect solution. Individual amp packs integrated into each loudspeaker reduce the amount of physical box clutter in the room. Assigning individual purpose-built amplifiers to each band-limited driver is much more efficient. A single much larger amp driving an equivalent passive loudspeaker will be dumping power into the passive crossover filter networks as unutilized waste heat. Each of the five identical SCM20 ASL monitors sports a 200w high bias class AB amp driving the mid-woofer and a 50w amp of identical design driving the tweeter. The waste heat of all five loudspeaker amps combined is far less than that of the pair of 140w ARC tube mono-blocks I once owned.

In my experience, the no-compromise application of active drive (with purpose built line level crossovers and amplification) will offer a level of sonic fidelity and efficient use of electrical resources that simply can't be matched by the same drivers and a passive crossover. Now I'm not claiming that the cheaper active loudspeaker iterations with DSP based crossovers and cheap switching power amplification are a shining testament to active loudspeaker superiority. Far from it- LOL! Cheaply/poorly implemented active drive will be sonically bested by superior passive loudspeaker designs. However, every time I hear an excellent multi-way passive loudspeaker design driven by a well matched partnering power-amp... I wonder how much better it might sound if implemented in an active design.

vincehoffman

Owner
According to my high-end AV tech (he provides authorized warranty service for dozens of hi-end audio companies) the only applicable modification is the removal of those unnecessary DC blocking caps and replacement with wire jumpers. There is no internal signal wiring. All input and output jacks are PCB mounted. Dan the "uber-tech" said he doubted he could scratch build and sell an equivalent for what the ARX RS-1 goes for at Markertek.

vincehoffman

Owner
Hello @jumia

The pair of ARX RS-1 stereo XLR switch boxes (one for Left & Right main loudspeakers and one for the subwoofers) are completely passive. The PCB mounted XLR jacks are good Amphenol units and switching is performed by high quality telecommunications grade relays actuated via a 12v trigger signal. With no 12v trigger voltage applied, the signal pass-through defaults to my 2-ch set-up. When I power up the Anthem HT pre-processor, it sends the 12v trigger voltage and the relays switch over to the multi-channel signal path.

Because I was concerned about the utmost signal transparency, my favorite tech humored me and removed the DC blocking capacitors from the ARX switch box signal path, replacing them with wire jumpers. Modified as described, the ARX RS-1 switches have proven to be completely audibly transparent in-circuit and work seamlessly.

vincehoffman

Owner
To Barron and the five other gentlemen whom have left such positive comments on my current system post thus far, thanks so much for the kind words gentlemen.

vincehoffman