Recommended Components Fall 2022 Edition Room Acoustics Treatments

Room Acoustics Treatments

Acoustic Geometry Small Curve: $399.99 ★
Medium Curve: $449.99 ★
Deluxe Curve, Walnut Frame: $549.99 ★
Deluxe Curve, Red Oak, Stained Black Frame: $549.99 ★
Acoustic Geometry's Curve System comprises Diffusors, Absorbers, and Corner Traps, each 42" high and available in a number of fabric choices. Each model is built on a wooden frame with a wedge-shaped cleat for hanging the product from a matching piece attached to the wall. Diffusors include a Mass-Loaded-Vinyl (MLV) membrane and are intended to control low- and midbass frequencies; Absorbers are essentially the same design as the Diffusors, but have an acoustically transparent front and don't include the MLV membrane; Corner Traps are triangular wooden frames filled with recycled cotton. In EL's listening room, the Curve System created a wider soundstage and greater clarity. Diffusors: $339.98$639.98, depending on width. Absorbers: $320.98$395.98, depending on width. Corner Traps: $697.98. Prices based on Guilford fr701, Anchorage and Acoustic Suede. All other sizes and fabric options quoted on individual basis. (Vol.35 No.2 WWW)

ASC StudioTrap: $639 ★
Adjustable tripod-mounted room-tuning device that represents the "latest in TrapThink from ASC," according to J-10, who uses an array of StudioTraps to great effect in his Manhattan loft. The front half is treble-reflective for a brighter sound, while the back side is treble-absorptive for a drier acoustic. He highly recommended the Traps for "anyone whose family will allow them to populate the listening room with gobos." (Gobos are "sound-absorbing panels used to surround performers in recording studios.") Stereophile's "Accessory of 1999." (Vol.21 No.12 WWW)

ASC SubTrap: $699–$899 ★
This "big, chunky black box" sits under a subwoofer to attack acoustic problems caused by the interactions of a subwoofer's output and the room's modes. Improvements in room acoustics were immediate, thought KR, even with the subwoofer disconnected: "There was less apparent energy from clapping, loud conversation, or just stomping around." With the system turned on, there was "less apparent bass energy from all wide range signals." With a Paradigm Servo-15 sub sitting atop a SubTrap, bass was deeper and more detailed: "Ah, yes—glorious bass without the boom!" Available in three sizes: 15", 18", and the 22" square model reviewed. (Vol.27 No.9 WWW)

ASC TowerTrap: $709–1389 ★
Originally called the Cube Tower, the TowerTrap is a "smaller, more cosmetically acceptable, more affordable version of the classic TubeTrap," writes BJR. "Very effective at taming mid- and upper-bass room anomalies. Looks like an attractive Vandersteen speaker sitting there in the corner." (NR)

ASC TubeTraps: $539–$1099 ★
Relatively inexpensive but remarkably effective room-acoustics treatment. TubeTraps soak up low-to-high bass standing-wave resonances like sponges. WP agrees, using Traps to optimize the acoustics of his room for MartinLogan SL3 electrostatics, while BD used them to optimize his room while auditioning the Thiel CS7.2s. Using the Music Articulation Test Tone (MATT) from Stereophile's Test CD 2 (STPH004-2), he first positioned them for smoothest overall response and articulation, then "dialed-in depth, dimensionality, and ambience." A chart recorder graphically showed the changes. In the end, "The sound was fantastic," quoth BD, who recommends them unconditionally. (Vol.9 No.3, Vol.15 No.2, Vol.16 No.12, Vol.19 No.1, Vol.20 No.5, Vol.23 No.2 WWW)

Auralex SubDude II: $59.99 ★
An MDF platform 23" long × 15" wide, covered with a carpet of thick felt and supported by two risers of high-density isolation pad, the SubDude has a rated load capacity of 300lb. KR found that the SubDude significantly isolated his Paradigm Servo-15 subwoofer from the live wooden floor and made the sound "tighter and fuller, but, conversely, less obtrusive." When used under full-range speakers, the SubDudes offered similar bass results while affecting high-frequency performance. Current SubDude II has a lower profile than the original sample reviewed. (Vol.27 No.12 WWW)

Bag End E-Trap: $1760 ★
Uses active electronics to control an acoustic device that acts directly on room acoustics rather than imposing anything on the electronic signal path. With its 10" driver, controls, and power amplifier in a box measuring 18" H × 13" W × 9.5" D, the E-Trap looks like a small subwoofer without input terminals. "While the appearance of the E-Trap is generally not noted, its effect on room acoustics is substantial," praised KR. It canceled out the superimposition of room modes, providing tight, clean bass while reducing the effects of ambient noise. (Vol.31 No.7 WWW)

DHDI ZR Micro Twin Mk3: $949 ★
ZR Sample Rate 8 Bit Mk3: $466 ★
Delta H Design, Inc., or DHDI, is an acoustics and architecture firm in Los Angeles County that manufactures room-treatment products for the professional and domestic markets. Two of the latter are from DHDI's Zero Reflection line: the ZR Micro Micro Twin, which measures 24" × 48" x 1.25" and is covered with fabric, is intended for placement directly behind one's speakers, while the curiously and clunkily named ZR Sample Rate 8 Bit ($383) is a 20" × 40" × 0.75" sheet of MDF into which has been CNC-carved an intricate pattern of ridges. After treating his room with two ZR Micros and three ZR Sample Rate 8 Bits, JM noted an appreciable improvement in sound: "I loved it. Indeed, I was taken aback at how much of an improvement I heard." (Vol.38 No.4 WWW)

PSI AVAA C20 electronic bass trap: $3125 each ★
In a field dominated by DSP products, the AVAA C20 stands out: this response-correction device uses pure analog technology. Inside the AVAA C20—its name stands for Active Velocity Acoustic Absorber—is a microphone, a perforated membrane, a velocity transducer, and an amplifier with feedforward and feedback. In principle, the C20 converts incoming pressure waves into velocity waves, thus absorbing them. It is said to work on pressure waves between 15 and 150Hz without affecting other frequencies—and more than one C20 can be used in a given room. In a guest review for Stereophile, acclaimed mastering engineer Bob Katz described the AVAA effect as more of polishing than "fixing" per se and praised the active C20 for working well in tandem with his more traditional (and sizable) passive trapping products. (Vol.39 No.6 WWW)

Ready Acoustics Chameleon Super Sub Bass Traps: $309.99 ★
The Chameleon Super Sub Bass Trap measures 48" high × 24" wide × 6" thick, and is available in eight fabric covers and four frame colors, allowing it to be employed without dominating the view. Assembly and installation were simple. The Chameleons were "audibly and measurably more effective" than KR's Echo Busters corner traps, and produced "undeniable" improvements in the midbass and bass. (Vol.32 No.9 WWW)

RealTraps MondoTraps: $350 ★
Corner MondoTraps: $370 ★
The MondoTrap is a large (57" H × 24" W × 4.25" D) acoustic absorber built from "double-density" rigid fiberglass and covered in a sound-transparent fabric. In addition to imparting to bass instruments a "fuller, clearer, more palpable" sound, the MondoTraps seemed to reduce a "glaze," allowing Jim Austin to hear deeper into the music. "Far from deadening the room," he said, "the MondoTraps made the music more involving." "I really liked what the Mondo Traps did in my room," adds KR, "although I have to agree with Jim (and my wife) that their appearance better suits a studio or dedicated audio room than a regular person's lifestyle." Adding four MondoTraps to WP's small listening room resulted in punchier, more coherent bass. Corner MondoTrap, designed to fit unobtrusively into a corner of a room, costs $350. (Vol.30 No.8, Vol.33 No.2 WWW)

RealTraps: $150–$700, depending on size and type ★
With these fiberglass panels set up across the junction of room boundaries and in corners, KR heard major improvements in imaging, detail, and soundstage width: "Every sound in the room, real or reproduced, is more defined in character and location." While KR was greatly satisfied with the results, he admitted that the panels were visually imposing: "The stand-mounted HF MiniTraps are in the way all the time." MiniTrap, $200; HF MiniTrap, $200; MondoTraps, $300; stands, $80. (Vol.28 No.1, Vol.29 No.11, Vol.33 No.2 WWW)

Stillpoints Aperture II acoustic panel: $960 (any color) ★
A refinement of the original Stillpoints Aperture—a 22" square wall-mounted room-treatment panel said to act as a diffuser, an absorber, and a resonator—the Aperture II is lighter in weight and easier to mount. According to MF, it's also better looking—and even more effective: "The illusion of my room's sidewall boundaries disappearing became even more convincing." (Vol.42 No.6 WWW)

Totem Beaks—Acoustic Tuning Pods: $150/pair ★
The Beak is a precision-machined, bullet-shaped device, about 2" high × 1.5" in diameter, that's intended to be placed atop a speaker to control parasitic resonances. When the Beaks were used with the GoldenEar Triton Two loudspeakers, highs gained clarity and extension, percussion instruments had greater presence, and voices became more tightly focused, said RD. "The improvement wrought by the Beaks was such that I wouldn't want to be without them," he said. See also EL's Totem Forest review in Vol.33 No.1. (Vol.35 No.2 WWW)

COMMENTS
Auditor's picture

The text under the J. Sikora Initial is the same as under the J. Sikora Reference, which is obviously a mistake.

John Atkinson's picture
Auditor wrote:
The text under the J. Sikora Initial is the same as under the J. Sikora Reference, which is obviously a mistake.

Fixed. Thank you.

John Atkinson
Technical Editor, Stereophile

lesmarshall's picture

I was very surprised to read that the Benchmark DAC 3 is no longer a Recommended Component . In the earlier 2022 edition of Recommend Components , it was an A+ component . Your stated reason for the deletion was because it was not auditioned in a long while . Well why not audition it then ? Also, why is an audition necessary ? It measured as one of the best DACs ever . Why would its measurements change simply because you have not auditioned it recently ? I understand its your policy , but it seems rather unfair to Benchmark that you no longer recommend it for that reason . I believe a much fairer policy would be that a highly rated component should only fall off the recommended list if it is auditioned periodically and you determine that its current level of recommendation is no longer justified based on the factors that you use to include a component of the recommended list .

JRT's picture

Les, toward some light hearted amusement, consider a reductio ad absurdum.

The quoted material below was excerpted from the first version (published 01 May 1963) of Stereophile's recommended components, just the A,B,C rated amplifiers and preamplifiers:

Quote:

Preamplifier-Control Units
A: Marantz 7, McIntosh C-20
B, C: Dynaco PAS-2

Power Amplifiers
A: Marantz 8B, McIntosh MC-60 (footnote 5), Marantz 9A (footnote 5)
B, C: Dynaco Stereo 70

Footnote 5: mono amplifier.

Reductio ad Absurdum... Should the old gear listed above continue as currently recommended gear, or is it best left in its original context in the circa 1963 article? ...and why or why not? ...and is it a much too different set of cases for comparison? ...why? Would that old gear be good fodder for a listing of recommended vintage gear, and is that good subject matter for the current Stereophile readership? These are mostly rhetorical questions, but not all.

JRT's picture

Would you also include the essentially similar PAS-3, and then also the PAS-3X with updated tone controls, and then maybe also Frank van Alstine's improved Super PAS Three, etc.? The original short-list can grow large.

https://www.stereophile.com/content/recommended-components-1-0

https://www.stereophile.com/tubepreamps/1088vana/index.html

georgehifi's picture

It would be nice if the "title" of the piece recommended was clickable, so one could easily then read the full review of all these thousands of "recommended components" instead of searching like a ???

Just a thought??

Cheers George

liquidsun's picture

I must say I'm surprised to see Perlistens into Restricted Extreme LF category as I thought they were full range speakers.

Kal Rubinson's picture

For most, they will be full range but, as you can see from JA's Fig. 4, the FR is rolling off smoothly below 100HZ such that it will easily mate with a complementary subwoofer. I believe that was Perlisten's intent. That said, unless you are assessing the sound of low, low organ pedal tones, explosions or thunder, the bass from the s7t is clean, powerful and musically satisfying.

Robin Landseadel's picture

There's a lot of Dance Pop/Techno music that gives the lowest octave a workout. Managed to blow out the small bass driver from a Paradigm bookshelf speaker with a Sarah McLaughlan track---"I Love You" from the album "Surfacing"---a quiet ballad with a synth bottom without overtones, so there's pure, deep bass. Another good example would be the work of Bill Laswell, a producer/bass player.

Kal Rubinson's picture

OK but how is this relevant? On the one hand, I am not surprised that one can blow out the small bass driver in a bookshelf speaker. On the other, I doubt if it would do that to the Perlisten.

Robin Landseadel's picture

Blowing out the driver of a Paradigm Atom might not be meaningful save that I blew it out with a track that is low in level and undynamic. More to the point, it sounds like the speakers in question could use a sub. Of course, you pointed out that the speakers in question are designed to integrate well with subs. My Infinity 250 speakers, small floor-standing speakers, also requires a sub for deep bass.

What is meaningful is that there is more to the bottom octave than organ pedals and explosions. Lots of modern productions take advantage of digital recording/playback's ability to record/reproduce the lowest octaves of sound.

Kal Rubinson's picture

Yes, there is a lot more to the bottom end than I cared to mention but the distinction between the small Paradigm Atom and the s7t is that the former needs a sub (or a LP filter) merely to survive wide-band signals while the latter does not.

Did you read my comments about the Garage Door test? I doubt that either your Paradigm or your Infinity could compete with the Perlisten, with or without a sub.

Robin Landseadel's picture

Doubtless. My point was more about program material and really deep bass. In any case, my Infinity Primus 250s are aided by my Sonance Son of Sub. As the system is in a small room, it's probably as much bass as the room can take.

Anton's picture

I like to hit this issue and pretend all my Hi Fi gear is gone and I have to start over with my budget and this list.

Glotz's picture

Droooooool.. and I'm done FOREVER.

Soulution, MBL... heaven.

KEFLS50W's picture

It will be interesting to see if Stereophile catches up to the focus on active, integrated designs. The relevance of separates seems to be waning in comparison to these sexy and modern designs (many of which are good value to boot) from KEF, B&W, Q Acoustic, ATC, Dali, and others. LS50WII for example gives me access to high quality, high current class a/b amplification I would not have been able to afford with separates. On another note, why are REL subs not listed - they would floor the competition listed in terms of sonics and build quality. Sorry but SVS is a home theater product and KEF KC62 is for kids.

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