Text and photos by Juan C. Ayllon Straight off, vibration is not a big issue in my 20’ x 16’ listening room. Located in our basement, the vinyl, faux hardwood floors rest on a cement slab. With a hallway to the left and a fireplace on the right, I employ a large area rug, large acoustic absorption panels, acoustic curtains, several bass traps and an acoustic diffusion panel, as well as sound dampening Dacron Fiberfill behind paintings and thick recycled denim insulation behind my diffusion panel and curio cabinet to deaden the room. They have served my wife, Belle, and me well, whether listening listening to jazz down low on weekend mornings, louder blues, rock and other genres during the day and quite loud when taking in HD movies, The Voice (our favorite reality TV singing competition that starts again on Monday), or simply dancing to the music. Recently while listening, however, I tapped on the top shelf of my equipment stand next to my Lampizator Lite 7 DAC and heard it booming through my speakers. I knocked several more times and, sure enough, they broadcast into my listening space. I knew that vacuum tubes like those used in my Lampi could be microphonic, but, wow! I was surprised how clearly I could hear taps resonate into the room. I did the same test next to my Technics 1200 turntable when I was playing a record and, sure enough, the knocking came through my speakers! Clearly, the vibrations were being picked up by the stylus! It wasn’t long before I reached out to Norman Varney of A/V RoomService, Ltd. to find out more about his Equipment Vibration Protectors (EVPs), as they had piqued my interest when I spotted them on an audiophile Facebook page. Glancing at his website, I read the following description of what makes the EVP special: The EVP core is a matrix of precisely compressed high-density molded glass fibers, which allows controlled air movement through the fibers. This action provides viscous damping, reducing physical motion, while widening the frequency bandwidth of attenuation. As sound energy moves fibers against fibers, the friction transfers sound energy to heat energy. The annealed fiberglass is produced by a multiple flame attenuation process which generates fibers having modulus of elasticity of 10.5 million PSI (738,223 kg/sq. cm) and nominal fiber diameters of less than .00027 inches (6.8 microns). The matrix of the glass leaf springs is bonded at all fiber intersections with a low VOC water-resistant binder during the molding process under controlled heat and pressure. The material is then stabilized by multiple precompression cycles to many times the maximum published load capacity for the specific density of the media. (“Equipment Protectors Tech and Spec Sheet”) A look at their testing data, which were conducted at the Owens Corning Acoustic Lab, proved encouraging (click here to read it) It turns out that Varney is a pretty cool person. In addition to being an acoustic engineer, he’s a talented and connected musician. Noting that I liked jazz guitarist Larry Carlton from posts I’d made on Facebook, he wrote, “I used to hang out with Larry as a teenager before and after gigs when he lived in the Hollywood hills in the late 70s. Played drums with him and met a lot of great musicians. Even went to an AES show with him and Jay Graydon.” When I questioned the benefits of isolation devices with my listening room sitting atop a concrete slab, he wrote back, “Though you may not have irritating resonances and vibrations from the concrete floor over grade, it does still vibrate, the spikes directly couple the speakers to the floor, which the walls and ceiling are connected to. Decoupling is what vibration isolation is all about.” Explaining how his isolators work, he said, “To eliminate vibrations means to break its path, or absorb the mechanical energy by transforming it into heat energy, which is what EVPs do.” Next, he asked for the weights of my electronics to determine which density of EVPs to send out for review. After I responded, he suggested that we isolate the Technics SL 1200 and the Lite 7 DAC with four, two-inch High Density EVPs and the VPI Voyager phono stage with three, two-inch Medium Density EVPs (you can see them in their online catalog here) “Normally I suggest the speakers first, as they are the source of vibration, followed by the most sensitive piece(s) of equipment to vibrations second,” he wrote. However, we both agreed that placing EVPs under my speakers might raise the height of the tweeters and change their sound signature in my room. They arrived, wrapped in cellophane, in a box about a week later along with a bubble level. They were attractive enough; costing $39 each, they were roughly one inch thick and two inches square, with a stiff, black, spongy core sandwiched between two roughly 1/16” metal plates covered in black felt. They appeared delicate and when asked, Varney confirmed this fact. “EVPs are fragile,” he wrote via email. “The core is made of layers of fiberglass that work like leaf springs. They can separate easily.” I noticed that several of them weren’t quite the same thickness and asked him about this. “Sometimes uncompressed EVPs may be slightly taller or shorter than others, but they will even out under proper loading,” he wrote. “You may also find that equipment weight is not centered. For the EVPs to perform properly, they need to be loaded properly. “Beyond that, it is only important for the turntable and loudspeakers to be bubble-level, your phono pre-amp does not need to be,” he continued. “Regardless, the EVPs can be moved around so that the equipment is level and loading evenly.” As for my Technics, he said that the easiest way to balance it was under a platform which he suggested should ideally weigh at least three times the weight of the turntable (although this is not required). “I had a granite piece for my turntable which has five EVPs under it,” he added. My Turntable Setup is 'Born Again' Not possessing a turntable platform, I searched on Craigslist for inexpensive wood suppliers. Originally looking to purchase some reclaimed barn wood, I visited a shop, Born Again Barns and Lumber Company, in nearby Antioch, IL. It’s a barebones operation and, when I arrive, a lady is answering the phone at a folding table and two men are building wall joists. A burly bearded gentleman in a plaid shirt shows me around and, immediately, I am impressed with lovely raw walnut slabs leaning against the wall. “We can get you something in the size you want for about a hundred bucks,” he announces. When I say that I am looking for something substantially less costly, the salesman dons his coat, walked me across their ice covered rear lot to a warehouse, where he finds a raw maple slab that's roughly 18”x3”x”25” that he can sell me for $20. He cuts it down to 23” wide on a table saw, walks it back to the main building, has his man run it through a powered planar several times to save me hours of sanding and hands it off to me for a crisp, $20 bill. I am pumped! Several days later, I putty a gouge, sand it down, clamp and glue a long crack, apply light stain and several coats of Tung Oil. It is gorgeous and ready to use three days later! Taking care to place the EVPs carefully, Belle positions them while I lift, then lower the DAC, turntable isolation platform, and VPI Voyager phono stage preamplifier. Now, it is time to play some music. Listen and Learn Playing music at lower levels on up through the 80 decibel range, we don't really notice a difference in noise floor, dynamics or detail. “Do these things really work?” Belle asks. “Be honest,” she adds, reminding me that readers may rely on me to make informed decisions like she does when shopping on Amazon. We turn the sound levels up to 85 dB - plus to watch several HD TV action and drama serials and movies over our flat screen 60" TV and my sound system. With the Hsu Research ULS-15 Mk2 subwoofer thundering and shaking us with its massive, 15” driver we both noticed more lifelike clarity in voices and sound quality. It's pretty amazing, really. We both smile. “Wow, that really does sound better,” Belle enthuses. In the weeks that follow, I notice a slightly lower sound floor when the volume is turned up (usually while Belle is still at work or out shopping), channeling living and breathing jazz, rock, blues and alternative performers into our living room. Moreover, when I perform the tap test on the shelf next to my DAC and turntable, I do not hear it through the speakers. Turning to Belle, I ask if she hears it. “No,” she responds. "Am I supposed to?" Listening to several songs for my recent Qobuz USA review, I appreciate the wondrous, minute details emerging from my Usher Mini Dancer Two speakers. More often than not, performers and their instruments are palpable presences just behind the speakers. Wiping down the Hall ‘N’ Oates’ ‘Rock ‘N Soul Part 1” vinyl album, I place it on my Technics and lower the needle. Daryl Hall and John Oates. “Sara Smile.” Rock ‘N Soul Part 1. RCA Records, October 18, 1983. John Oates’ mournful and glowing Fender Stratocaster arpeggio lead-in sounds very pleasant and warm. The keys, Scott Edwards’ bass, Jim Gordon’s drums and Daryl Hall’s silky vocals sliding from vulnerable tenor to falsetto and back again shimmer. Oates’ velvet falsetto backgrounds and interspersed, harmonized leads are warm and vivid. Granted, this isn’t my Ortofon Quintet Black cartridge that I keep in reserve for turntable reviews, but the Ortofon Blue 2M, and this is a Technics 1200, not a VPI Prime, but nevertheless, for a mass produced pop record, it's not sounding bad at all! Now, I’ve heard it said before that, in terms of strengths, everyone’s system favors either digital or vinyl playback. Mine is decidedly digital, so firing up my Lampizator DSD Komputer and Lite 7 DAC, I compare digital files streamed from Qobuz USA and from my personal digital music collection and am pleased with the results (you can read that full review here). Take Qobuz’s 192kHz/24-Bit FLAC presentation of Cassandra Wilson’s “Strange Fruit” (Cassandra Wilson. New Moon Daughter. Blue Note. 1995.), for example: The lighting of a cigarette, Lonnie Plaxico’s low key pizzicato on upright bass, Lawrence Morris’ mournful cornet, Chris Whitley’s odd plucked acoustic guitar comps and Cassandra Wilson’s smoky contralto vocals in a resonant room sound perhaps a smidgen cleaner as the harmonics in her voice light up the 63 to 250kHz range of my RTA analyzer than my 44.1kHz/16-Bit AIFF recording (maybe due to more headroom, as my copy plays several decibels louder), With both versions, their presence in the room feels undeniable, clearly articulated presences just behind the Ushers. On Qobuz’s 44.1kHz/16-Bit presentation of Fausto Mesolella’s “Suite N” (Fausto Mesolella. Taxidi. Fone Records. 2017) the intonation of his acoustic guitar, his loop pedal and the reverberant, old wine cellar of the Palace of Scoto di Semifonte in Certaldo Alto where it was recorded sounds virtually indistinguishable from my Native DSD DSD64 download version (DSD is a trademark name used by Sony and Philips for their system of digitally recreating audible signals for the Super Audio CD (SACD -- read more here ). ("About DSD"). It sounds like I am sitting right there in the cavernous wine cellar, the lovely music swirling about me with the late Mr. Mesolella standing 10 feet away, his foot manipulating the loop petal. Concluding Thoughts As I mentioned earlier, the perceived differences in sound quality and sound floor were not that pronounced at more normal playback levels (i.e., under 80 dB). However, as the volume went up notably and bass levels rose via my Hsu Research ULS-15 Mk2 subwoofer, both my wife and I noticed an improvement in clarity with voices and other fine details that may have been slightly obscured without the EVPs to isolate my Lampizator Lite 7 DAC’s microphonic vacuum tubes from the subterranean bass. Also, with some music, I noticed a slight lowering of the noise floor. For an audiophile and reviewer with a highly sensitive and revealing system, that’s pretty significant. And, chances are we won’t stay in this home, with its cement slab undergirding the stereo system forever; as retirement approaches, we will likely downsize. And I have little doubt that the differences would be more pronounced if our listening room’s floor sat on floor joists, instead of a concrete slab, as they had at our former home. Bottom line, the EVPs are keepers. Associated Software and Equipment
Work Cited “Equipment Protectors Tech and Spec Sheet”. AVRoomService.com. AV RoomService, 2019. Web. 24 February 2019.
4 Comments
Dan Starr
3/3/2019 05:09:29 am
Juan, this is an enjoyable article! I use an A/V stand from Best Buy (should an audiophile admit this?!?) with glass shelves supported by a wood frame. The shelves rest on metal attached to the wood. My room is a finished basement - carpet over a concrete floor. I’ll try your “resonance test” to check for the noise you experienced.
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3/3/2019 08:07:07 am
Hi Dan,
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3/6/2019 06:10:32 am
Hi Dan,
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Christopher Dynak
12/23/2019 02:33:04 pm
I bought a maple cutting board from webstaurant.com. I also bought some silicone hemispheres from Hudson HiFi. Self adhesive. Stick on 4 corners. Equal spacing. Boom. Isolated for just over $40.
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