Volti Audio • Razz Loudspeakers

by Mark BLackmore | November 13, 2020

© www.theaudiobeat.com

The introduction of Volti Audio's Razz speaker was of particular interest to me. I love low-power amplifiers, particularly single-ended-triode (SET) models. When I purchased my first SET amplifier 15 years ago, it looked like there might be a resurgence in high-efficiency speaker designs, with more and more manufacturers jumping on the bandwagon. Unfortunately, that bandwagon never materialized, but some manufacturers have kept the flame burning. Volti Audio speakers boast high-sensitivity woofers (direct-radiating or horn-loaded), with horn-loaded midrange drivers and tweeters. The Razz is the company's smallest and least-expensive model, and its 97dB-per-watt sensitivity is aimed directly at audiophiles like me.

Before founding Volti Audio, Greg Roberts began his audio career rebuilding and modifying vintage Klipsch speakers, improving them with modern parts for higher performance. His rebuilds were primarily for three models in the Heritage line: the Belle, LaScala and Klipschorn. He offered improved tweeters, and proprietary, handmade wooden horns fitted with better-performing compression drivers and reworked crossovers. He was so encouraged by his results that he combined his success in audio with his considerable woodworking skills and Volti Audio was born. Despite becoming a full-time speaker manufacturer, Roberts continues to modify Klipsch speakers, and that part of the business remains a significant portion of his company’s workload.

Weighing in at 90 pounds and measuring 40” tall by 15” wide and 12” deep, the Razz is a substantial-looking speaker, particularly if you are accustomed to narrow-front-baffle designs currently offered by most other manufacturers. Pricing depends on the choice of real-wood veneers with walnut, mahogany, cherry, and maple as standard finishes. Premium veneers include Bosse cedar, rosewood, red gum, and blackened ash, each finish adding $1000 to the standard price. Roberts says the Razz is his first speaker that can be shipped by FedEx or UPS, saving the customer the added expense of pallet shipping via freight lines. The Razz is also his first speaker to have component panels cut by a local CNC shop, so customers can be guaranteed quick delivery, because finished speaker cabinets can be kept in stock. Before the Razz, all Volti speakers were entirely built by hand, so this new speaker represents quite a change in terms of manufacturing.

Constructed of 1"-thick Baltic plywood, the cabinets are remarkably free from extraneous cabinet vibrations, and easily pass the knuckle-rap test, producing a deep, dead sound. In this respect, they compare favorably to other manufacturers’ construction, even those using exotic cabinet materials. The front and back panels have a durable textured paint, and the review pair was finished in cherry. The Razz’s veneer, fit and finish are excellent, if not quite to the standard of Volti’s more expensive Rival SE or Vittora, which are woodworking works of art. I should also make note of the excellent shipping boxes supplied with the Razz. They are double-walled, with the speaker suspended inside amidst thick foam inserts. This packaging should all but guarantee a safe journey to your home.

Volti Audio uses a cast-frame 12" woofer with neodymium magnets for the Razz and rates its response down to 35Hz. The midrange frequencies are supplied by a 2" compression driver utilizing a composite-material diaphragm mated to a shallow, wide-dispersion horn made from cast aluminum. Volti uses extensive sound-damping materials on the external surfaces of the horn to lessen any chance of ringing. Highs are delivered by a 1” horn-loaded tweeter that also uses neodymium magnets. The crossover utilizes 14-gauge copper inductors, metal-oxide resistors and metalized polypropylene capacitors. The input plate is made from laser-cut Lexan and allows for biwiring. Finally, a substantial grille is included. Its CNC-cut surfaces minimize edge diffraction, and it is held in place with magnets. Due to the front panel being inset, the panel edges stand proud by 3/4", so I recommend always listening with the grilles in place to avoid diffraction issues.

Once we had unpacked the Razz, Greg Roberts placed the speakers approximately 60" from the wall behind them and 84" apart. He would have liked them even wider, but my listening room wouldn’t easily accommodate much more than that. He told me that the Razz should be toed in so that their axes cross about eight inches in front of your nose at your listening seat. His recommended seating position for my living room was only 68" from the speakers, a bit closer than an equilateral-triangle arrangement recommended by some manufacturers. This quasi-nearfield arrangement was actually ideal, and I did not perceive the imaging as too wide, nor did the music feel too close, as though I were wearing a huge pair of headphones.

The review pair of speakers was new, with only a couple of hours of play on them. Until break-in was complete, the bass was a bit characterless and lacking in texture, so you'll want to give the woofers some time to settle -- about 15 hours of play in my case. I investigated the low-end response with some warble tones and found that the Razz began to trail off under 30Hz, with 20Hz being inaudible in my room. On the plus side, the Razz's bass was very strong down to 30Hz, and I never wished for greater bass extension.

With the speakers in Greg's recommended placement, the center image was focused and tightly defined, with a mid-hall perspective. The speakers did not reproduce vast amounts of depth in recordings, but they were very good in the lateral placement of images. The best way to describe the Razz's reproduction of soundscape is that it brings musicians to your front room more than transporting you to the recording venue. In that respect, the Razzes are similar to the Altec Valencia speakers that normally reside in my listening room.

I began serious listening with Chris Jones’s Roadhouses and Automobiles CD [Stockfisch SFR 357.6027.2], a brilliant recording of folk/country/bluegrass tunes given Stockfisch’s usual audiophile treatment. "No Sanctuary Here" has a thunderous opening bass guitar riff featuring Grischka Zepf on five-string bass playing low D and low C. Those notes are 36.7Hz and 32.7Hz, respectively, and the Razz reproduced them at full volume, rattling a few window panes. Zepf’s playing is also effective in the song’s chorus, combining with the background male voices to mimic Mongolian throat singing. The next tune, "Fender Bender," is a bluegrass duel between Jones and Zepf, and the Razz's 12" woofer had no trouble keeping up with the fast unison runs between bass and guitar. I think anybody who has played bass guitar will feel a certain sense of familiarity with the tone and power of the Razz's woofer. Its speed of attack and decay are reminiscent of the performance of bass-guitar combo amps I’ve used on gigs, and I mean that as a compliment.

I was pleased with the Razz’s reproduction of Chris Jones’s vocals, delivering his big, rich baritone with great presence, but I wanted to examine the woofer-to-midrange crossover region in more depth to hear if Volti Audio had been able to blend the doped-paper woofer with the horn midrange. I turned to two recordings that have been on my playlist this summer. First up was Lynn Harrell and Yuja Wang’s recording of Rachmaninov's Cello Sonata, Op.19 from Deutsche Grammophon, the 16-bit/44.1kHz Qobuz stream. Harrell’s cello was tightly focused between the speakers, with good evenness of tone and no added weight on his lowest string sound. But Wang’s piano part reached a bit lower and benefitted from the Razz’s bass rise so that the lowest notes played by her left hand were more energetic and exciting at climactic points in the piece.

Interestingly, Janos Starker’s famous LP, Bach Suites for Solo Cello [Mercury 432 756-2], sounded drier, less reverberant, with more control of his tone than I’m used to, but it managed to retain the energy and brightness of his upper register. The Razz certainly moved Starker’s image farther back than I am used to hearing. With my Altec Valencias, the cello image is much more forward, with quite a bit of woody resonance. I find both speakers’ reproduction of this album enjoyable, and if I prefer the Valencia’s exuberance, I imagine the Razz is a bit closer to the true sound of the recording.

Staying in the string family, a surprisingly realistic presentation from the Razz was of Ray Chen’s newest release, Solace [Decca], the 16-bit/44.1kHz stream on Qobuz. Chen has chosen six tracks from Bach’s Six Sonatas and Partitas for Solo Violin, recording a "lockdown album" in his new home studio. The Razz projected Chen’s violin tone far in front of the speakers, with a good balance of bow, string and body. Portraying Chen’s beautiful tone and vivid playing, the Razz’s low distortion encouraged me to play this recording at higher-than-realistic volume.

At CES a few years ago, Marc Mickelson introduced me to Rickie Lee Jones’s cover of the Rolling Stones’ "Sympathy for the Devil," from her album The Devil You Know [Concord], which I replayed via the 16-bit/44.1kHz Qobuz stream. I usually listen to this with an almost indifferent attitude, just letting Jones's vocal idiosyncrasies wash over me. With the Razz, her voice became pleading, slippery, almost serpentine as she half sang, half spoke Mick Jagger’s words. Now it became an eerie performance, and my wife even commented that she always knew the song was dark, but this performance struck her as creepy and unnerving. I have to give Volti Audio credit for the Razz’s midrange-driver implementation; few listeners would identify the use of a compression driver coupled to an aluminum horn. The crossover was almost seamless and lacked any hint of nasality or honkiness that so many audiophiles associate with horns.

My relationship with the treble range depends on speaker positioning and choice of amplifier. The Razz's midrange horn plays quite high, and the tweeter is only reinforcing the top audible octave. Using Volti Audio's recommended seating position, the listening axis crossing in front of my seat put my ears about 15 degrees off-axis, helping blend the midrange and tweeter. It’s not difficult to position these speakers for a good blend, but you’ll need to spend time getting this right or the tweeter’s contribution will be too easily identified.

The most important factor turned out to be amplifier choice. Using either a Yamamoto A-08 or A-09, or a BAT VK-60, the treble was clear and well-integrated, with the BAT amp verging on being too dark. My working hypothesis is that all three of these amps do have similarly smooth treble and somewhat high output impedance that interacts with the Razz's tweeter impedance, producing a synergistic partnership. But if I listen to my more neutral Innersound ESL amp, the treble balance becomes a bit too hot for my tastes.

When I mentioned this to Greg Roberts, he said he had designed the Razz to have replaceable resistors to accommodate different acoustics and electronics. After the new resistors arrived in the mail, I received a detailed e-mail, including pictures, describing the process of removing the midrange horn and swapping resistors. Behind the horn, on the right side of the cabinet, is a small resistor board held firmly in place by a wing nut. Once the nut was removed, the board could be lifted out of the cabinet and the tweeter or midrange level could be changed by replacing resistors. The supplied Lynx-brand resistors I installed reduced the tweeter level by about 2dB, and I did the bulk of my review with the tweeter at this level. With the midrange horn removed, it was instructive to see inside the Razz, noting the quality of the CNCed bracing, the large-gauge wiring, and the Solen and Jansen capacitors used in the midrange/tweeter crossover. The entire procedure took 30 minutes, and I wish every manufacturer offered similar options for consumers.

At the beginning of this review, I wondered if the Razz would be compatible with flea-powered SET amps. The answer is yes, but with some reservations. First, my Yamamoto A-08, with 45 tubes, simply ran out of steam at anything above polite conversational levels. I suppose this was to be expected, because that amp produces only one or two watts, depending on load. A Pass Labs ACA amp with 8 watts of class-A power was a nice choice, but when pushing the Razz to higher volumes, the Pass amp’s sound hardened in the treble, making me turn the volume down. Almost like a muscle car with lots of horsepower, urging you to stomp on the accelerator, the Razz’s clean sound urged me to play music a bit louder than I might normally listen. Unsurprisingly, an inexpensive Yuanging (50-watt) class-D amp that I use primarily for speaker break-in had more than enough power, but the treble was far too coarse and gritty, a problem the Razz was all too willing to expose. This is not an especially forgiving speaker, despite its warmish tone.

So, what worked particularly well with the Razz? Listening to my Yamamoto A-09 led me to believe good 300B amps will be a great choice. The sound of the A-09 was seductive and musically satisfying, but its nine watts will probably rule out Mahler or Montrose. The 300-watt Innersound ESL solid-state amp exerted great control, even when pushed to louder-than-normal listening levels. I did exercise some caution because I was exceeding Volti Audio’s 8-80 watt amplification recommendation, but the Razz never gave up or sounded strained. However, I did miss the full tone and texture of the Yamamoto amp.

Roberts told me during his visit that he’s a big fan of EL34 push-pull amps, so I brought out my vintage Conrad-Johnson MV52. This was my first audiophile purchase, and it continues to be musically satisfying, even after decades of ownership. The sound with the Razz was excellent, with smooth highs, a lush midrange and just enough control of those 12" woofers. This amp proved to be a great match for the Razz, responsible for the best listening sessions I had with the speakers. If my Yamamoto amp produced a more seductive tone, the push-pull Conrad-Johnson amp gave more oomph and produced bigger dynamic swings. And while the MV52 gave up ground in soundstage width and depth compared to the Yamamoto, it wasn’t by much, and the C-J amp countered with better pace and rhythm. I’m sure readers can think of many current pentode and tetrode amps that might produce similarly good or better results with the Razz.

The Razz is a welcome new entry in the high-efficiency speaker market. Audiophiles looking to try SET amps using 300B tubes or lower-watt push-pull amplifiers will find a great match with this speaker. The Razz does have a warm personality, but the bass was extended with plenty of slam. I was impressed with its smooth, clear midrange and the ability to tailor the treble to my satisfaction. During the Razz’s stay, two audiophile buddies stopped in for a short, fully-masked listening session. When the music stopped, their conclusion was simple: the Razz is just so much fun!

Price: $4999 per pair.

Warranty: Five years parts and labor.

Volti Audio
6100 Nashville Highway
Baxter, TN 38544
www.voltiaudio.com

Associated Equipment

Analog: J.A. Michell Gyrodec turntable with Orbe platter and bearing; Ortofon TA110 and Zeta tonearms; Sumiko Amethyst and Ortofon SPU CG 25 mono cartridges; Fosgate Signature phono stage.

Digital: BorderPatrol DAC SE digital-to-analog converter, ZENmini Mk 3 music server and LPSU power supply.

Preamp: Yamamoto Soundcraft CA-04.

Headphone amp: Yamamoto Soundcraft HA-02.

Amplifiers: Conrad-Johnson MV52, InnerSound ESL, Pass Labs ACA, Yamamoto Soundcraft A-08 and A-09.

Speakers: Altec Lansing Valencia, InnerSound Eros, Magnepan LRS.

Headphones: Audio Technica ATH-W1000.

Cables: BPT IC-SL and MIT Shotgun S1 interconnects; BPT SC-9L and InnerSound ESL speaker cables; BPT C-9 and L-9CST, Yamamoto Soundcraft (came with amps) and Shunyata Research Venom power cords; Shunyata Research Venom USB cable.

Power distribution: BPT 2.0 and CPT.

Room treatment: Zanden Audio AP-1 panels.

© www.theaudiobeat.com