Vinnie Rossi LIO modular integrated amplifier Page 2

One night, while listening to the LIO, I hauled out a wonderful recording by pianist Raymond Lewenthal, who wails as he plays and conducts Funeral March for a Papagallo and Other Grotesqueries of Alkan (LP, Columbia Masterworks M30234). On most any system, this LP will let the piano sound quite realistic. But forget sound—this disc is all about Raymond Lewenthal's messianic and fitfully inspired pianism. He doesn't just play the keys and pedals—he engages the whole instrument. I played this record with (don't laugh) a $75 Shure SC35C moving-magnet cartridge on a $2100 Abis SA-1.2 tonearm (I hear you laughing!) through the LIO driving the Falcon Acoustics LS3/5a's, and I swear on my best Gutenberg Bible that I have rarely in my life heard a piano sound this real and corporeal in my room. Sure, the BBC monitors are mini, but that day they played BIG! Incredibly, I have never heard any digital recording reproduce a piano with this amount of texture and weighty authority. I could hear the microtextures of felt-covered wooden hammers striking the coil-covered piano strings. I could hear the effects of Lewenthal's pedaling. It was revelatory. I loved it.

Magnepan .7
In my review of the Magnepan .7, in the August 2015 issue, I explained how the Vinnie Rossi LIO played the .7s beautifully in my smallish room, but began to lose its breath at around 90dB. Nevertheless, I kept going back to this pairing because it brought out every last drop of sweet lushness the LIO was capable of. Record after record, I bathed in the almost fragrant beauty of the LIO plus Slagleformer plus .7s as I played all genres of music. But—if you like your music loud and louder, this pairing will not satisfy.

What happened was this: The Maggies need current. The LIO's power supply and MOSFET output stage have low impedance and high energy-storage capacity, and therefore can supply driving current with almost limitless grace. But as Vinnie Rossi reminded me, "As long as you play at levels that don't exceed the rail voltage (don't push the amps into clipping), they should work very well together."

The Maggies provided a perfect opportunity to examine how the Rossi clipped. Normally, the LIO sounded very open and breathy. But when it clipped, its trachea collapsed. And when the LIO really clipped, it started to choke, and the music got closed-in and flat.

I spent a lot of my listening time playing the LIO through the KEF LS50s because the sound was so agreeably natural. The sound of the Falcon LS3/5a's through the LIO was more "alive" and had better tone character, but what the KEF-Rossi combo did best was relax, step off the stage, and let the musicians run the show.

DeVore Fidelity Orangutan O/93
Unlike RCA's Nipper, I do not have to cock my head to know when recorded music sounds exceptionally real. I can just put on an album like folk singer Susanne Rosenberg and organettist Christophe Deslignes's Out of Time and Country (CD, M•A Recordings M080A), walk out of the room, pour myself an S. Pellegrino with lemon, and then, as I walk back in, stop and think, Oh, damn—now I remember why these DeVore Orangutan O/93s have been my reference speakers since I began writing for Stereophile: They play music exactly the way I (and my little dog, Monster) like it!

My Line Magnetic LM-518IA integrated amplifier (review to come in October) powers the DeVores with sweet, colorful confidence. So did the Vinnie Rossi LIO. Both amps shone through the Orangutans a kind of late spring light—not too cool and dark, not too warm and bright. But when I switched from the LM-518IA back to the LIO with the DeVores, it felt as if I'd jumped from a turbo Porsche with racing tires into a Tesla S with autopilot. The LIO has the Tesla's type of quiet power: its massive torque is applied smoothly and equally at all rpms. I experienced unprecedented naturalness of bass.

The LIO as preamplifier
I connected the Rossi LIO's preamplifier outputs to a variety of power amplifiers, including Simaudio's excellent, 125Wpc Moon Neo 330A ($4300; review in the works). Used as a preamp, the LIO was just as invisible as Simaudio's famously transparent Moon Neo 350P preamplifier ($2499; also under review). And, happily, as they disappeared, the Rossi and the Moon Neo 330A still managed to reveal enjoyable smidgens of tasty, just-picked freshness in every recording.

Let us pretend that I own an LIO that is doing a delightful job of playing the Magnepan .7s, but that I now want loudness levels of up to 100dB, up from a max of 90dB. No problem—I can just swap in a stronger power amp, keep the LIO as a preamp, and still retain the larger portion of the Rossi magic. (This fall, at the Rocky Mountain Audio Fest in Denver, Vinnie Rossi will introduce a standalone power amplifier that will deliver 100Wpc into 8 ohms, and can be used in lieu of the LIO's 25Wpc amplifier module.)

The LIO as headphone amplifier
Want to see the eye of the Cyclops? Wanna make your socks go up and down and your hair fly back? Listen to Formatia Valea Mare, a septet of six winds and percussion, play their delirious Rromani "muzika orijinal," as they call it, on their Departe De Casa (CD, M•A Recordings M060A) through the LIO headphone amp connected to Sony's revealing MDR-7520 headphones. The tone-perfect sounds of the tuba came right out of those eargoggles and tickled my scrotum. The accordion and clarinets massaged my heart. The trumpet and flugelhorn sounded more like sweat-stained brasses than any others I have heard.

I used the extremely neutral Vinnie Rossi headphone stage to drive each of my pairs of quite different-sounding headphones, and, more than any other headphone amp I've used here, the Rossi plainly showed me the level of colorations inherent to each.

The LIO as DAC
I've always called my Halide Design HD (USB) DAC ($495) my Mac DAC because I bought it to connect my Mac mini to my Creek 4330 integrated amplifier. I loved the colorful, nondigital way it played high-resolution files and film scores. But nowadays, because most integrated amps I review have digital stages, the Halide, like an old horse, has been relegated to only occasional use, driving my Schiit Asgard headphone amp. And then I started thinking . . .

Because the Vinnie Rossi LIO is such a shape shifter, it seemed relevant to investigate how its DAC compared not to my memory of DACs in other integrateds, but to a pair of standalone DACs I already use and find admirable. I let my Onkyo Integra DPS-7.2 transport drive the LIO DAC via the latter's optical input. I let my Puresound A-8000 CD player drive my Line Magnetic LM-502CA DAC ($1800) via the latter's coaxial output. Finally, I let the Mac mini drive the Halide Design HD DAC. The Halide's and Line Magnetic's outputs entered the Rossi via analog inputs. With this setup, I could play a single album like John Hicks, Buster Williams, and Louis Hayes's On the Wings of an Eagle (SACD/CD, Chesky JD318) and use the Rossi's remote to shuttle among a trio of DACs.

The effect of this stratagem was edifying. The LIO made the Halide DAC sound even more soft and generous than it usually does. But surprisingly, the Halide demonstrated more bass slam and room air than I remember it ever doing. Unfortunately, this newfound slam was wasted—the Halide also sounded fuzzy and warm to the point of distraction. In comparison, the Vinnie Rossi DAC was Claritin-clear and well controlled, but less spacious and airy than the little Halide.

To further assess the LIO DAC's resolving powers, I played the dramatic and rhapsodic 11,000 Virgins, a collection of vocal music by Hildegard of Bingen, sung by Anonymous 4 (CD, Harmonia Mundi HMU 907327). Through the LIO, each of the four women's voices projected its own pure energy into the well-defined volume of the Christian Brothers Retreat, in Burbank, California. My room was transformed into that dreamy acoustic.

One day, gazing at the LIO's remote, I noticed a button: Filters. When I looked in the manual, I realized that Rossi had included it to provide a choice between the LIO DAC's Linear Phase and Minimum Phase filters. I've always been suspicious of linear-phase filters, blaming them for digital sound's metallic weirdness. So, happily, I used a bunch of tracks from Chesky and M•A Recordings to explore the differences. To my taste, Minimum Phase sounded subtly but distinctly more relaxed and colorful than Linear Phase—music felt more elastic, and seemed to move along less mechanically. But Vinnie—what about a No Filter option?

I could hear the beauty
The Vinnie Rossi LIO should not be understood as just another integrated amplifier—it's considerably more than that. According to Vinnie Rossi, "The LIO is designed to become the last audio component you might ever need." To my ears, it delivered the best of tubes (color, vividness, liquidity) and the best of solid-state (quietness, control). Its highly adaptable modular design combines a fashionable Italianate aesthetic with near-state-of-the-art sound. It was as musically natural as fish jumping and birds singing in trees. The LIO phono stage was nearly faultless. Its DAC was exceptional, and enjoyably nonmechanical in sound. Amazingly, the LIO's best feature might be its headphone amp.

My current gold standards for the potent, transparent reproduction of music are the Komuro PP845 and Pass Labs XA100.5 monoblocks. While the LIO didn't quite match the Nori Komuro or Nelson Pass designs in strength, dynamic ease, or richness of tone, it did come ridiculously close, albeit with a quieter, gentler personality. If there is a more innovative and musically satisfying integrated amplifier than the Vinnie Rossi LIO, I have yet to experience it.

Vinnie Rossi
800 Main Street, Suite 125
Holden, MA 01520
(774) 234-0800

music or sound's picture

I hoped for an explanation of the main feature of the LIO. Each Ultra (or super) capacitor has apparently 350F with a max voltage of 2.7V and 9 of them have to be connected in series for each bank to reach 24V with 34F. So the statement of "6300F at 2.7V of total charge under the hood if they all were connected in parallel" is completely misleading because there are not connected in parallel. One bank is charging during the other supplies voltage separated from the charging circuit. As capacitors do not supply a constant voltage when discharging how is that voltage regulated? How often is a switch between banks necessary and does that switching have any influence on sound?

Vinnie Rossi's picture

Hi Music or Sound,

Correct - and Herb asked me about the total capacitance under the hood, which is 6300F worth of ultracapacitors. In use, each bank is approx. 38F (equivalent to 38,000,000uF) as 9 caps, each 350F, are connected in series.

You are also correct about the ultracapacitors not supplying a constant voltage (as they discharge). Over the course of approx. 10 minutes, they slowly discharge by about 4V. All modules downstream are linear voltage regulated, and the ultracapacitor bank in use always feeds them with a higher voltage than what we are regulating to.

Cap banks switching approx. every 10 minutes. It cannot be heard in the speakers or headphones. It happens very quickly (a couple of milliseconds) via relays switching the + and - terminals. Switching has no influence on the sound whatsoever, and at NO time is any of the audio circuitry connected to the capacitor bank that is charging, which is connected to the grid via an external AC to DC power adapter. So only DC enters the LIO. No internal power supply transformers. And the audio circuitry is ALWAYS 100% disconnected from the power adapter (which gets power from the mains). No matter how clean or dirty your power is, it has no influence on any of the audio circuitry because they always run isolated from it.

Feel free to contact me if you have any other questions. I'll be happy to clear things up for you. You can learn a lot from our website.

All the best,

Vinnie Rossi

Venere 2's picture

Are you related to Walter Rossi the guitarist? Ever build him a guitar amp :-)

dreite's picture

According to JA, the unit switches capacitor banks every three minutes with a 1WPC load and there IS an audible click. And the power amplifier performance is considerably short of the published specifications.
I also don't understand 60Hz (and components) making their way into the measured performance if the circuitry is "ALWAYS 100% disconnected" from the power adapter.

If your objective testing indicated better performance than JA measured, you should have noted that in your reply on the "Manufacturers' Comment" section of the print Stereophile. If he made a mistake in his testing, I'm sure JA would be more than willing to entertain an explanation(s).

John Atkinson's picture
dreite wrote:
According to JA, the unit switches capacitor banks every three minutes with a 1WPC load and there IS an audible click.

Audible in the quiet of my test lab with me sitting next to the amplifier. But with music playing on speakers, the click will be masked.

And forgive my impatience with the original poster, but he should have read the entire review before commenting.

dreite wrote:
I also don't understand 60Hz (and components) making their way into the measured performance if the circuitry is "ALWAYS 100% disconnected" from the power adapter.

Spuriae at the wall AC frequency and its odd harmonics are primarily due to magnetic interference, so as the LIO does not have a hefty power transformer and has that hefty ultracap supply, I was puzzled by this. I did check the possibility that my test equipment had some ferrous content, like the switches in the load resistor bank, but this did not appear to affect the LIO's measurements.

The noise and distortion performance of some amplifiers is approaching the point where factors like this can be seen. But the LIO's power amplifier module doesn't get close to equaling those amplifiers.

John Atkinson
Editor, Stereophile

CG's picture

AC remnants are really hard to get rid of in most test set-ups. The transformers in most - but not all - power supplies are close to saturation at some part of the incoming AC waveform, especially if there's junk on the ac power. This comes with the territory, especially with capacitor input power supplies. When the transformers reach that non-linear point of their magnetic properties, they tend to radiate a lot. This can very easily couple into the equipment under test as well as the test set-up itself.

There's thousands of references on this topic to be found in a Google search.

Vinnie Rossi's picture

Hi Venere2,

I am not related to Walter Rossi (or Carlo Rossi, or Martini and Rossi) - lol!

Hi dreite,

Since the review unit was made, we started applying damping material on the internal relays for the ultracap bank switching. If no music is playing and you are right next to the LIO, you probably will still here a slight 'click' when the banks switch. With music playing, I doubt you will hear anything from LIO (and certainly not in the speakers, headphone output, or preamp outputs).

Hi JA,

I was also puzzled why you measured some 60Hz components, especially since the LIO's power adapter is external (so only 24Vdc is fed into the LIO to charge the capacitor banks). Even using very sensitive IEMs (headphone jack), we could not hear the slightest bit of 60Hz noise or harmonics. I'm wondering if they were getting into the LIO via the external connections during the test process (maybe via the signal grounds)?

Best regards,

Vinnie Rossi

jmsent's picture

regarding the linear regulators in the power supply? Does that include regulating the supply rails for the output transistors? And, regarding the switching time between banks, I am assuming that the 10 minute figure you gave was with the amplifier in idle with no signal at the speaker terminals? JA got a much shorter switching time of 3 minutes with just 1 watt output, and I assume that would be shorter still at full output?

Vinnie Rossi's picture

Hi jmsent,

Yes, the circuity for every active module (e.g. dac, phonostage, power amp, etc) features linear voltage regulation. In some cases, multiple linear voltage regulators. For example, the dac has separate regulators for the clocks, the XMOS chip, the d/a chips, the analog output stage, etc. And no switching regulators are used for any module (no DC-DC converters).

Regarding switching between banks, the timing does vary based on how you have your LIO configured. Configured just as a dac, phonostage, or linestage w/o tubes runs longer than with the speaker output module, as there is typically less avg. current draw. If you have your LIO configured with the speaker output module, there is some quiescent current always being drawn when the speaker output module is ON, and there is also current draw that depends on the impedance of your speakers and how loud you play.

Running a constant 1W per channel via a test tone into an 8-ohm resistor will likely draw more average current than listening to music (except maybe when playing at loud levels and/or into lower impedance speakers). It is unlikely that the banks will be switching in less than 3 minute intervals, but it is still possible and it makes no difference if they switch every 3, 5, 7 or >10 minutes. The listener does not need to be concerned about this as the process is automatic and seamless. To the listener, the LIO is either turned ON or OFF like any other component.

Please let me know if you have any additional questions, and also feel free to contact me via email and/or phone call.

Best regards,

Vinnie Rossi

otaku's picture

Does John or Vinni or anyone else here have any knowledge or ideas about the similarities and differences between the LIO's Ultra DC supply and Bel Canto's Virtual Battery Supply (VBS), particularly in the C7r?

Vinnie Rossi's picture

Hi otaku,

They are quite different. From reading the VBS white paper, they are using a switch mode power supply (SMPS) that is always connected to the audio circuitry (not disconnected from it like a battery, or ultracapacitor banks as in the LIO).

Somebody please correct me if I misinterpreted this.

Best regards,

Vinnie Rossi

corrective_unconscious's picture

I don't understand the market for products like this: Apparently sophisticated and certainly expensive...but with so few watts. Bluetooth "capable" speakers strike me the same way, whatever their price level - they just don't seem to make sense as values. (Although I can understand people don't like cables.)

aslee's picture

Wonder if it can be powered by good quality SLA or LiFePO4 batteries?
If so, any further improvements in sound?