Inserting a new component into a well-considered audio system is kind of like getting an organ transplant. Cables and other accessory “tweaks” can to some degree act as anti-rejection drugs, but mostly, the system either welcomes the invader or fights it. For a reviewer, if the sonic results are harmonious, great!
If the system sound takes a turn for the worse, it doesn’t mean the new component is not worthy. It may very well be that the piece under review does not work well in the context of the reviewer’s system. That complicates the job, but an experienced hand can isolate the component’s contribution to the system’s sound, describe its particular sonic characteristics, and perhaps even recommend the context in which its addition might be beneficial. A consumer looking for an upgrade usually knows where he or she wishes to take the sound. A reviewer usually does the installation to cover an assignment.
The job here is to review the VTL TP-6.5 Series II Signature phonostage—a happily accepted assignment. I’ve reviewed positively and enjoyed listening to more than a few VTL products and once owned a pair of VTL 300 power amps designed by Luke Manley’s father David, when I first wrote for The Absolute Sound three decades ago. The two outboard phono preamps I own, the CH Precision P1/X1 and Ypsilon VPS-100S plus outboard Ypsilon large step-up transformers, cost considerably more than the VTL TP-6.5.
Behind the original 6.5’s familiar cosmetics and operating system are a series of significant circuit upgrades to the hybrid tube/JFET design newly derived from the top-of-the-line TL-7.5 Series III Reference linestage preamplifier, as well as, according to VTL, “newly designed, more robust power storage for the active mc stage.” VTL claims the newly upgraded Series II “substantially improves upon the performance of its predecessor.” Since the original 6.5 has not been in my system, I can’t vouch for that, but no matter.
Other design highlights include specially designed, radiation-cancelling power transformers located as far away as possible from the mc stage, fast-recovery low-noise diodes, gain trims for accurate channel balance, low-noise metal-film resistors, “reference quality” coupling capacitors, and a rigidly braced, shielded against EMI and RF, steel-and-aluminum chassis.
Though VTL stands for “Vacuum Tube Logic,” phono preamp logic suggests solid-state quiet—at least in the first amplification stage— to deal with today’s low-output moving-coil cartridges. Thus, the hybrid JFET/tube circuitry here, which combines the benefits of first-stage solid-state quiet with the particular sonic qualities and electrical characteristics that attract many to vacuum tubes.
The zero-loop-feedback 6.5 circuit incorporates, among other features, passive RIAA, multiple low-noise cascaded regulators, and shielded power supplies, all packaged within a single, relatively compact, high-mass chassis. The mc input can produce up to 68dB of gain from its balanced outputs. VTL claims a “design breakthrough” is the use of shunt regulation in the Series II’s power supply, which maintains constant voltage for superior ripple rejection by shunting excess current to ground.
While you might not be interested in this important “technicality,” what will probably be of great interest is the resulting claimed lower background noise, increased image stability, and improved delineation of midrange and midbass frequencies. VTL claims that this produces more “air” around voices, greater extension, and more “nuances” that create “an overall more lifelike impression” with greater speed and dynamics in the all-important active mc stage. The active mc stage benefits from the latest gel-capacitor technology, which permits far greater capacitance in much smaller packages.
The TP 6.5 Series II Signature phonostage comes in two “flavors.” One, costing $15,000, includes the aforementioned active hybrid J-FET input that drives a high-current 12AU7-based mc gain stage, as well as a conventional 12AX7-based mm input that drives the passive, hand-selected, tight-component-tolerance RIAA stage. The circuit’s other tubes are a 12AT7 phase splitter for the +6dB balanced stage and a 12AT7 buffer that couples to the output using large, bypassed coupling caps. The 12AX7/12AT7 combo is fairly mm standard circuitry, distinguished here more by execution than by novel design.
The second 6.5 “flavor” adds $3000 to the price and replaces the mm input with a second mc input, this one step-up-transformer-coupled via high-quality Lundahl transformers that produce a fixed 65dB gain from the balanced output and 59dB gain from the single-ended output. Loading via the transformer secondary, appropriate for low-output, low-internal-impedance cartridges, is front panel switchable to 47, 100, 470, and 1k ohms. In addition to producing required gain, transformer-coupling improves mechanical damping, which can greatly benefit the tracking performance of some moving-coil cartridges.
Luke Manley sent both versions. With either one, switching between the two single-ended inputs occurs after amplification to avoid losses otherwise produced by switching the miniscule low-voltage cartridge outputs.
Operating System
In addition to the red front panel power button, six others select input (mc, mm), mono, phase, RIAA, and mute. Buttons on either side of the numeric display adjust gain and loading. The standard moving-coil input load choices, which you toggle through, are 100, 250, 470, 4.7k, 47k, and “User Defined” (you can solder in your own resistors on the circuit board). Moving-magnet load choices are 10k, 22k, 47k, and “User Defined,” which is a welcome option for mm aficionados who know that 47k is just an arbitrary and not often accurate value adopted as a “standard” for convenience’s sake. Moving-coil gain choices are 44dB, 50dB, 56dB, 62dB, and 68dB. The transformer-equipped version’s input is fixed at 59dB from the single-ended output and 65dB from the balanced output. Transformer secondary loading options are 47, 100, 470, and 1k ohms.
Despite the front panel’s apparent simplicity, nested functions abound, hidden “behind” the buttons. They can be used to disable an input (not sure why you’d want to, as there are only two), lock and unlock load and gain settings for each input, put the two channels out of phase with one another, engage or not the rumble filter (curiously, no specs provided), and the (spurious, IMO) “Enhanced” RIAA so-called “Neumann Pole.” LED color changes for all these functions apprise you of their settings. VTL supplies a small, but very handy multi-function remote that from your seat lets you select among all the basic functions and toggle through their various settings.
I ran both 6.5s balanced out, and while I’ve got a nice supply of “Bugle Boy” 12AX7s and other highly regarded tubes, I reviewed the 6.5s stock as suppled and did not indulge in “tube-rolling.”
The Countdown
When you first turn on the TP-6.5 Series II, the numeric display counts down the warm-up from 180 to 0 after which the red power button turns blue and thus begins your hopeful journey into sonic ecstasy, whether or not you listen to Steely Dan.
Mine began with the transformer-equipped version, which means I listened to both inputs. For this review I mainly used the new $9999 Ortofon MC Diamond cartridge (review forthcoming). With its low 0.2mV output, I felt it a good choice and challenge for a tube-based phono preamplifier. Plus, Ortofon cartridges, for whatever reason or reasons, like transformer coupling. I also listened with the Lyra Atlas Lambda SL ($11,995, also 0.2mV) and a far less costly ($2695) Luxman LMC-5 (review at TrackingAngle.com), which outputs 0.4mV.
Thanks to Jacob Heilbrunn, who studied trumpet at Oberlin college (and who also enjoys blowing his own horn), I learned about A Festival of Trumpets (Nonesuch H-71301), a wonderful Marc Aubort-engineered recording mastered at Sterling Sound by Bob Ludwig (Aubort engineered many of the great Vanguard “Stereolab” recordings). These Aubort/Ludwig Nonesuch records are almost all sonically and musically superb and not at all costly. This one features The New York Trumpet Ensemble directed by trumpet virtuoso Gerard Schwarz accompanied by timpani, violins, cello, bassoon, harpsichord, and organ playing compositions mostly written in the 16th and 17th centuries.
Giovanni Gabrieli was the only composer familiar to me. The one I came away most appreciating was Johann Christoph Pezel (1639-1694), whose Sonatina No. 62 for two trumpets and continuo (bassoon, harpsichord) told me that while both the transformer-coupled and hybrid input delivered the piece with assured textural delicacy, microdynamic precision, and especially vivid three-dimensionality on an airy, wide, and deep soundstage, the hybrid tube/JFET input was clearly superior—at least for the MC Diamond. The hybrid tube/JFET input produced a sweeter, more transparent picture that alleviated the transformer input’s slight trumpet glare—even loaded at 47 ohms. The bassoon sounded rounder, more distinctively woody, and thus more believable. Either input though, produced the most subtle “kiss of liquidity” and musical flow that distinguishes a tube-based phono preamp from a solid-state one.
The just-released double album Monty Alexander The Montreux Years (BMG BMGCAT573DLP) confirmed that previous observation. The somewhat tinkly piano heard through the transformer input was transformed into a timbrally and texturally more complex and believable instrument, rich with woody overtones, especially when the pyrotechnical Alexander tickled the upper keys. Side one’s second track, Nat Adderley’s familiar “Work Song,” demonstrated the 6.5 Mk II’s muscular, well-controlled bottom-end extension and especially its control in the area where tubes sometimes produce a “plummy” effect that some people like and I don’t. Alexander is backed by the Harlem Kingston Express, featuring both acoustic and electric bass, guitar, and two drummers. Alexander’s piano was simply “there” between the speakers, the Casino Barriére’s ambience filling the space between, behind, and to the sides of the speakers. This record through this phono preamp produced maximum listening pleasure in every way.
Since the mc input was identical in the other 6.5 MK II “flavor,” I installed it and did all of the rest of the review listening through it, starting with Mel Tormé and Friends (Finesse W2X 37484), an extraordinarily realistic-sounding small club recording (Marty’s, a now defunct Upper East Side New York cabaret) with Mel skirting the jazz and cabaret boundaries, backed by a trio plus guest “friends,” including Janis Ian and Gerry Mulligan.
Mel’s take on Billy Joel’s “New York State of Mind” takes the tune to a level Billy cannot have imagined when he wrote it. The late Apogee founder Jason Bloom turned me onto this one so many years ago. The tape has gone missing, so I buy every copy I find, though at Record Surplus in Santa Monica I passed on a pricey autographed copy.
I’m listening for Mel’s “velvet fog” voice to be mellifluous, light, and airy, but alarmingly well-focused between the speakers with not a hint of artificial etch or, conversely, midbass bloom. The attack of Jay Leonhart’s bass should be clean and precise, fully expressing the finger pluck followed by a pleasing woody sustain. You should hear and see the instrument on the stage. The applause should sound as natural and believable as recorded applause can sound in a small space and not at all like rain hitting a tile roof. The 6.5 Mk II’s delivery of this live album put me in the club and kept me there for four sides. At the end of side four I said to myself “successful transplant.”
But there was more listening to be done because I’d not yet switched to the moving-magnet input using one of my Ypsilon step-up transformers. I chose the MC-26NL SE. Okay, it’s silver-wire wound, features a proprietary amorphous core material among other features, is large and heavy, and costs $19,200, but this transplant demonstrated the TP-6.5 Mk II’s considerable strengths as well as its minor deficiencies.
The big transformer enlarged the Marty’s stage, clarified Mike Renzie’s chording and elegant glissandos, and added macrodynamic expressiveness to both the piano and especially to Donny Osborn’s drum hits. Perhaps because of its additional gain, background black became more pronounced as the 6.5’s mm section had less to do. The transformer better gripped the notes and tightened everything without in any way damaging the picture’s delicacy and textural expressiveness.
Jay Leonhart takes an extended bass solo on “Pick Yourself Up,” Renzie does some Bach, and Tormé scats. The transformer/6.5 combo reproduced this track—especially the microdetails of the bass and piano attack—as effectively if not better than I’ve heard before. The transformer driving the VPS-100 produced max performance from the MC Diamond, which I’ve now listened to with a half-dozen phono preamp combinations. This combo produced one of those “Why not stop here and be done?” moments we all seek.
The great recording engineer Jim Anderson posted a photo on Facebook from the session that produced the cover for Sinatra’s Swingin’ Session!!! (Capitol SW 1491). So, of course, out came an original pressing of the album recorded in 1960, along with many sonic expectations, all of which were wildly surpassed. I hadn’t played it in years, so everything in the system has changed including the Wilson XVX speakers and the OMA K3 turntable. What a rocking Nelson Riddle orchestra complete with string section and featuring top L.A. session men, including reed men Buddy Colette and Plas Johnson and trumpeter Harry “Sweets” Edison. This group was explosive and could handle every curve Riddle’s arrangements threw at them.
I’ve never heard the whole thing hang together dynamically, spatially, and even timbrally quite as well as it did this play. Frank’s voice too, was locked center stage, sibilants cleanly rendered with just the right balance of chest and throat to create a “living voice,” whereas often before he’s sounded disjointed, with excess midbass and a somewhat thin, hard upper register. This was an “in the studio” experience.
You are not likely to buy a $19,200 transformer to go with a $15,000 phono preamplifier so what’s the point here? The point is that were I buying the TP-6.5 Mk II, I’d opt for the version minus the transformer input. That way you can enjoy the excellent mc input and go on your own transformer quest.
Before switching back to the mc input, I listened to the first two movements of Beethoven’s “Eroica” symphony with Otto Klemperer conducting The Philharmonia Orchestra from The Electric Recording Company’s nine-symphony box set (ERC 046), originally issued in 1962 on U.K. Columbia Records. Then, switching to the mc input, I listened to the final two movements.
“Eroica” is my favorite Beethoven symphony, and it wasn’t ruined by a college music-appreciation professor, who used the word “toy” to elucidate the melodies. So, he’d lay out the Eroica’s opening, for instance, by going “toy, toy toy…toy toy toy TOY.” He “toyed” us through all nine symphonies, but somehow my mind can mostly put away the toys.
Well, yes, the $30,000+ SUT/mm opening movements were presented on a wide and especially deep stage; the massed strings had gossamer delicacy and never turned hard; there was a vivid and rich display of instrumental colors; and macrodynamic swings had power and drama. Into the mc stage, the final two movements had much of the same—especially the vivid colors and the liquidity and flow that tubes produce— just in a somewhat diminished form and, of course, for a great deal less money.
Following the “Eroica,” I played through the mc input a 3rd U.K. Island pressing of Nick Drake’s Pink Moon (ILPS 9184). Even though it’s a later and lighter-weight press, the “1U” matrix number makes clear that it’s the first lacquer cut. His records didn’t sell all that well. Drake’s popularity came only after his death.
Listening to the familiar record through the VTL 6.5 Mk II brought forth all its strengths. John Wood’s Sound Techniques was a small studio located in London’s Chelsea area. The 6.5 Mk II delivered Drake’s dazzling finger picking with convincing and precise delicacy of attack, the confines of the modest studio space seeming to materialize behind the singer. It was a fully realized performance.
Conclusion
I listened for almost two months to the two versions of the TP-6.5 Mk II VTL sent, never switching back to my references to get a comparative listen, and not because I was slacking off. I was thoroughly enjoying what I heard and didn’t feel I was missing anything, not even on the bottom—even on electric amplified bass—where tubes can sometimes miss the tight grip provided by solid-state. So, why play the swap game? Most importantly, the 6.5’s timbral balance—its overall tonal personality—was pleasingly neutral and avoided imposing upon the music any kind of identifiable character.
Review complete except for this wrap-up: I still haven’t returned to either reference phono preamp. Grant Green’s Feelin’ the Spirit (Blue Note ST-84132/B0033488-01) plays at moderate level in the background, and both the “Tone Poet” and VTL’s 6.5 MK II nail this one. Transparency, transient precision and delicacy, harmonic richness (RVG got Herbie Hancock’s piano just right on this 1962 recording), and an enveloping sense of the large, open Englewood Cliffs studio space produce a “you are there” sensation (and I’ve been there!).
I greatly preferred the active JFET/tube input to the transformer-coupled input, though I most preferred my costly transformer into the mm input. A different cartridge or a different system might produce a different result, but I don’t think so. My only complaint about the 6.5 Mk II was that there was more background noise (“tube rush”?) than I like to hear, and I wish it had been quieter. But that’s it. Successful transplant. In an email, Luke Manley (whose signature could not be found anywhere on the “signature” phonostage) wrote that “we are selling all we can make of this design.” I believe it.
Specs & Pricing
VTL TP-6.5 Series II Signature Phonostage
Type: Hybrid JFET/vacuum tube phono preamplifier (with optional Lundahl step-up transformer for second input)
Tube complement: 2x 12AU7 mc; 2x 12AX7, 2x 12AT7 mm; 2x 12AT7
Outputs: 1 pair balanced out XLR, 1 pair single-ended out RCA
Maximum gain: Moving coil: 62dB single-ended, 68dB balanced; moving magnet: 34dB single-ended, 40dB balanced; transformer coupled mc: 59dB single-ended, 65dB balanced
Output impedance: 150 ohms
Input impedance (cartridge load): Selectable mc: 100, 250,470, 1k, 2.5k, 4.7k, 47k ohms, user defined; selectable mm: 10k, 22k, 47k ohms, user defined
Transformer coupled mc: 47, 100, 470, 1000 ohms
Frequency response +0/–1dB: 1Hz–100kHz
Maximum output voltage <1% THD: 10VRMS@1kHz (10k ohm load)
Channel separation: >70dB @ 1kHz (>65dB @ 20kHz)
Dimensions: 17½” x 4″ x 14¾”
Weight: 50 lbs. fully packed in one box
Price: $15,000 (mc/mm), $18,000 (mc/transformer-coupled mc)
VTL
4774 Murrieta Street, Suite 10
Chino, CA 91710
(909) 627 5944
vtl.com
Associated Equipment (for this review)
Speakers: Wilson Audio Specialties Chronosonic XVX
Turntable: OMA K3 (fully spec’d prototype)
Tonearm: OMA/Schröder 12″ SLM aluminum tonearm
Preamplifier: darTZeel NHB-18NS
Power amplifier: darTZeel NHB 468 monoblocks
Phono preamplifier: CH Precision P1/X1PSU, Ypsilon VPS100, MC-26LS SUT
Phono cartridges: Ortofon MC Diamond, Lyra Atlas Lambda SL, Luxman LMC-5
Cable and Interconnects: AudioQuest Dragon, TARA Labs The Zero Evolution, Analysis Plus Silver Apex, Stealth Sakra and Indra, and Dynamic Design Neutron GS Digital
Accessories: AudioQuest Niagara 7000 (line level), CAD Ground Controls; AudioQuest NRG Edison A.C. wall box and receptacles, ASC Tube traps, RPG BAD, Sklyline and Abffusor panels, Stillpoints Aperture II room panels, Stillpoints ESS and HRS Signature stands, HRS XVR turntable base, Thixar and Stillpoints amplifier stands, Audiodharma Cable Cooker, Furutech Record demagnetizer, Orb Disc Flattener, Audiodesksysteme Vinyl Cleaner Pro X, Kirmuss Audio KA-RC-1, KLAUDIO KD-CLN-LP200T, full suite WallyTools.
Tags: AMPLIFIER ANALOG PHONOSTAGE VTL
