Zesto Audio 

Although a relative new comer to the high-end audio industry, veteran recording engineer, producer and musician George Counnas has been around music production for decades.  He now takes on the role as chief designer at Zesto Audio.  Unhappy and uninspired with the performance and sound of many components he'd experienced, Mr. Counnas set his sights on designing and manufacturing high-end tube components that were in alignment with his knowledge of what music sounds like.  Their first component, the critically acclaimed Andros PS1 Phonostage is already a classic -- despite being on the market less than 3 years. The Leto PreAmplifier, their next component has also received wide acclaim from music lovers and reviewers alike. Their third offering, the BIA 120 Class A stereo tube amp completes George's trilogy of components, manifesting a true system approach.  Not to be outclassed by its siblings the Andros and Leto, the BIA 120 is already garnering raves and was recently declared to be the "best amplifier ever experienced in 50 years".  

 

Andros PS 1 Phonostage

The Andros Phonostage received a 2013 “Class A” Recommended Component from Stereophile & has been named a runner-up for Stereophile Analog Component of the Year.

The Zesto had an addictive, warm overall sound, with plenty of impact, detail and grace. 

I highly recommend the Zesto Andros PS1. It’s among the more enjoyable and satisfying phono preamps I’ve auditioned at any price.

– Michael Fremer, Stereophile’s Analog Corner – March 2013 

 

Fussy can be good. Zesto Audio's President, George Counnas, has loved music all his life — as a musician, record producer and audio engineer. He says, “It’s made me fussy about sound. That’s a good thing.” We agree.

 

Here’s George’s story about how he came to design and build the Andros PS1 Phonostage, in his own words:

“Digital technology has its place, but true audiophiles know that for the truest, purest sound, nothing beats analog. As I returned “home” to the warm, wonderful world of vinyl, I looked for the gear that would deliver the highest fidelity. I wasn’t satisfied. So I built my own.

“Vacuum tubes faithfully convert the delicate signal from my turntable and bring warmth and harmonic tonality like nothing else can.

“As a young man in England, I designed vacuum tube circuits. I worked for DECCA Navigator — at the time Britain’s largest electronics company — as part of a research and development team designing airborne navigational systems for the Royal Air Force.

“So I have many years of experience designing, creating and bringing to market high-end electronic equipment. The difference here is that no one’s life is at stake.

“I started doing research on past phonostage designs going back to the original RCA circuits of the 1930’s. These guys got a lot of things right, even though their tools were slide rules and trial and error.

“Their ‘classic’ designs were my starting point.

“But I had the advantage of CAD software to simulate electronic circuits. Ah yes, the old and the new. But even with the engineering skill, history, technologies, in the end it’s designed by how it sounds, by ear.

“Voila! Here’s my baby!

“One year later, after 71 circuit revisions with hundreds of component upgrades, I have a phonostage that I am proud to put my name on. It gives me joy to listen to music.

“The Andros PS1 Phonostage is my baby. I compromised on nothing.

“The resisters are very quiet, the capacitors are transparent, and the transformers have minimal distortion. To make sure its visual aesthetics lived up to its sound, I had an industrial designer (Musky Mistry) and an artist (Carolyn Counnas) collaborate to create an elegant enclosure that’s built like a tank. 

“In the end, however, the Andros PS1 is about what you hear. Hearing is believing.”

— George Counnas, President of Zesto Audio 

George Counnas clearly put a lot of heart, soul and mind into his Andros PS1 Phonostage. Once you hear what this thing can do, you’ll understand why. Wes Bender Studio NYC is thrilled to recommend the Zesto Audio Andros PS1 Phonostage. Zesto makes uncompromised audio components that are also an outstanding value. Hear it now at WBSNYC.

And we're not the only ones who think so.

The Andros PS1 won The Absolute Sound's Editor's Choice Award 2012 and was a featured top pick in their 2012 Buyer's Guide to Vinyl Playback. In the April 2012 issue, Paul Seydor said:

"Its sound is unbelievably smooth and velvety; harmonically rich, full, and vividly textured; marvelously rounded, tactile, and dimensional, with great body and solidity; and completely natural in its musicality and freedom from any of the usual sonic hype, audiophile style."

In fact, the Andros PS1 has garnered a lot of great press, here are just a few more: In Dagogo, March 2012, Ray Seda said:

"The sweetness and delicate nature of the Zesto Andros PS1’s delivery in the midrange and highs are almost counter-intuitive to its ability to also very competently amplify and deliver the sheer, explosive low frequency energy and dynamics that the record playback system sends to it."

In his "Highlights from T.H.E. Show Las Vegas / CES", Robert Harley says:

The system, put together by Zesto, Lindemann, and retailer Audio Revelation, was absolutely jaw-dropping in its presence and realism.

In fact, the Andros PS 1 made his "Best of Show"/"Best Sound (cost no object)".

In StereoMojo, January 2012, Michael Peshkin said:

"At its price, its performance competes with much more expensive units. In appearance and sexiness, there’s nothing that comes close."

In that same issue, Dr. John Richardson said:

" It’s physically beautiful, adaptable to many different cartridges by merely accessing the switches on the back panel, and most importantly, it will do real sonic justice to your valuable vinyl collection."

And John Fritz said:

"Owning a phonostage with state-of-the-art sonics? Wonderful! Owning one with balanced circuits and infinite adjustability? Outstanding! Having those adjustments not be tiny, cheap dip switches but high quality knobs and switches on the BACK so you don't have to open the case to make adjustments in real time? Amazing! Having it look like it belongs in a Museum of Modern Art? Unbelievable!"

Finally, here is an unsolicited email received from a happy customer:

wow!!!   The PS1 is sensational!  At 50 hours it was terrific.  But after 175 hours of around the clock burn-in, I’m climbing the walls with excitement! The Jensen transformers alone blow away my last reference...  As for the overall design, I’m truly hearing more stuff in my recordings than I’ve ever heard before!  I could go on and on with all kinds of adjectives to describe the performance of the PS1.  But since you’ve heard them all from others, I’ll just get back to some enjoyable listening.

Congratulations to Zesto Audio for a great design achievement!

 

 You can see a theme here. You can hear what they’re talking about here at WBSNYC!

 

More About the Zesto Audio Andros PS1 Phonostage

For true audiophiles, nothing equals the warmth, dynamic range and fidelity of vinyl records. A critical component of every music lovers vinyl playback system is the phonostage or phono preamp.

When a vinyl record is made the volume of the bass is reduced and the treble is increased. Otherwise, the bass would cut a groove too big for a stylus to read or for the music to fit the record. The phonostage reverses the process by taking the delicate signal from your cartridge and adjusting it so that the bass and treble are restored to their original volume. This common standard is known as the RIAA curve.

Inspired by RCA’s vacuum tube circuit designs from the 1930s, the Andros PS1 has been engineered to bring you the clarity and depth of the original recording. Your highs will be crisp but not overly emphasized, your midranges clear and present without being shrill and your lows full and firm without being boomy.

As we went through testing our panel of audiophiles marveled at hearing subtle nuances, discovering new things in recordings they’d played many, many times. They appreciated its clear stereo image with maximum channel separation and minimal phase distortion.

Words are inadequate to the task of explaining the Andros PS1. You simply must hear it to believe it.

Key Features

  • The Circuit is specifically designed to provide sufficient amplification to match your cartridge with the rest of your system. Each unit is hand built "Made in the USA".

  • 50 hour factory burn in on all circuits and vacuum tubes.

  • A low Noise level of -75dBu allows the quietest passages of you music to be heard.

  • The output circuit is designed to drive your cables and isolates the output from the influence of the next stage.

  • RCA connectors are high quality, Gold plated, recessed with an isolated ground.

  • Isolated ground RCA connectors plus the Ground On/Off switch will allow you to choose the best ground configuration.

  • Recessed RCA connectors are durable and will hold up to the typical Audiophile who loves to change their configuration.

  • All switches and knobs are easily accessible, nothing hidden inside to adjust.

  • 8 position adjustable MC load switch from 20 to 1000 Ohms

  • Accommodates both high and low MC output cartridges

  • Elegantly designed 16 gauge steel enclosure to help isolate the electronic “chatter” from nearby equipment.

  • Award winning Isonode anti-vibration feet

  • On/Off power switch conveniently mounted on front side panel

  • Easy to read large type on back panel

Specs:

  • Inputs per channel
    • Separate MM and MC inputs
    • MM/MC switch
    • MM impedance 47K Ohms
    • MM capacitance 100pf
    • MC Unbalanced ground isolated RCA or Balanced XLR3F
    • MC ground on/off switch
    • MC load impedance adjustable 1000, 400, 200, 100, 50, 40, 30, 20 Ohms
    • MC Internal step up transformers
    • MC High/Low switch with -10 dB gain for high output MC cartridges
  • Outputs per channel
    • Impedance 10K ohms
    • -10 dB Vu output level
  • Active Components
    • Four (4) Gold pin JJ ECC83S/12AX7 vacuum tubes with high quality ceramic sockets
  • Power
    • Ground binding post
    • Power consumption 27W , 0 drain when off
    • Voltage 110/120V AC 60Hz/li>
    • Optional factory installed 240V AC 50/60Hz
    • Standard 3 pin IEC power connector
    • ON/OFF power switch conveniently located on the front side
    • Two internal high quality linear regulated power supplies, 250V and 12V
  • Detailed Specifications
    • Gain MM input 45dB
    • Gain MC input 65dB
    • Noise - 75dBu
    • Frequency response complies with the original
    • RIAA curve within +or- 0.5 dB RIAA curve is achieved using a passive filter
    • 1% metal film resisters throughout
    • Polypropylene capacitors throughout the audio path
  • Other Features
    • "Made in the USA" using US and imported parts
    • Each unit is built by hand 50 hour factory burn in on all circuits and vacuum tubes
    • Dimensions 17" W X 12" D X 5" H Weight 20 lbs.
    • 16 gauge steel enclosure
    • Award-winning Isonode anti-vibration feet
    • Two-year limited warranty
    • Six months warranty on Vacuum Tubes

 

Leto PreAmplifier

Designer and co-owner George Counnas provides an insight into the provenance of his award-winning Leto preamp:

In 2011 we introduced our debut product, the Andros PS1 Phonostage. We have been gratified by the glowing reviews, industry awards and enthusiastic acceptance by audiophiles. Now we’re pleased to announce the Leto preamp, born of the same sonic bloodline: warm, musical and very quiet.

My design philosophy is to focus only on the important components and add nothing that could compromise the signal path. The only active components are the vacuum tubes that create a warm musical sound.

Balanced Means Lower Noise.

As a longtime audio engineer and producer, I’ve worked with a lot of professional equipment. I always preferred “true floating balanced” inputs and outputs because of their foolproof ability to isolate one piece of gear from the next. And that means lower noise for a strong, clean and quiet signal.

Easy to Use

The Leto preamp will compliment any system: tube, solid state or digital. It will work with single-ended and balanced input source or power amplifier combinations.

Focus on the Music

With the Leto in your system it will allow the sonic detail to come through, so you focus is on the music and the hardware will seem to disappear.

 

Key Features

  • The input selection uses only electromechanical switching to provide the most musical detail.
  • The wide frequency response allows you to hear the finest passages in your music.
  • True floating transformer balanced Inputs and Outputs have lower noise and isolate one piece of gear to the next.
  • Left and Right ground switches allows you to control the grounding of the single ended outputs.
  • The output transformers provide a strong and clean signal to your power amplifier.
  • Recessed RCA and XLR connectors are high quality, Gold plated, with an isolated ground.
  • All connectors are durable and will hold up to the typical Audiophile who loves to change their configuration.
  • No pops when the unit is turned on or off.
  • Automatically goes to mute when turned on or off.
  • Remote control Volume, Mute and Mono
  • The remote Mono helps you to trouble shoot your system.
  • Remote bypass switch overrides the mute in case the remote is misplaced.
  • 50 hour factory burn in on all circuits and vacuum tubes.
  • Elegantly designed 16 gauge zinc plated steel enclosure to help isolate the electronic “chatter” from nearby equipment.
  • Award winning Isonode anti-vibration feet
  • On/Off power switch conveniently mounted on front side panel
  • Each unit is hand built "Made in the USA".

Zesto-Audio-Leto-Preamp-back.jpg

We're very impressed with the Leto & so are several reviewer's who have experienced the Leto in their systems

Robert H. Levi writing for Positive Feedback (September 2012) gives the Leto his highest recommendation:  

New from Zesto Audio comes the tubed Leto Preamp, pushing the envelope in value and performance in its price range and beyond. With styling similar to the Andros Phono stage, the Leto is a powerful sounding, highly detailed, fantastically quiet, and superbly musical masterpiece that will complement the finest systems. Designed by a brilliant and pragmatic designer who knows great sound and ergonomics, the Leto performed like a thoroughbred in every way musical, and was a joy to control and adjust. The fun factor while working with the Leto made me rethink what has been missing in minimalist preamps that cost even more money these days. What a jewel! The Zesto Audio Leto is a killer design to my way of listening and loving recordings, and may just be the preamp you will buy and keep for the very, very long haul. The Leto receives my highest recommendation.  

Read the entire review.

 

Henry Wilkenson reviewed the Leto at Audiophilia (September 14, 2012)

I have spent many hours listening to the Leto and Andros combination at Wes Bender’s NYC/Studio. I have also listened to the Leto with the EAR 324 phono stage. The sound of the Leto is on the warm side of the spectrum but not so much as to be in any way objectionable. To be clear, this is not an ‘old school’ tube sounding amplifier. From top to bottom, the sound is very well balanced. It has enough resolving power to allow vocal and instrumental textures to be clearly heard. The Fairfield Four’s Isaac Freeman’s bass vocals are presented with their full richness, bloom and textures intact. I have heard this group’s vocals on other line stages that glossed over these details resulting in a bland presentation. Not so with the Leto...

Paul Seydor, writing for the Absolute Sound (March 2013) also weighed in with his thoughts after living with the Leto in his system -- referring to the Leto as Sonic Magic:

The Leto preamplifier, a linestage that is the second product of George and Carolyn Counnas’ Zesto Audio, is cut so completely from the same sonic cloth as Zesto’s Andros PS1 phonostage I reviewed last year that describing its sound would be to repeat more or less what I said then (Issue 222)

To get the whole story, read the entire review or give us a call to schedule a listening session!

 

Specs:

  • Inputs
    • 5 Inputs
    • 3 sets of Single Ended inputs with an impedance of 100K Ohms
    • 2 sets of true Balanced transformer inputs (pin 2 hot) with an impedance of 10K Ohms
    • Maximum input level of 4 Volts RMS
  • Outputs
    • 4 Outputs
    • 2 sets of true Balanced transformer outputs (pin 2 hot) with an impedance 150 Ohms
    • 2 sets of Single Ended outputs with an impedance 150 Ohms
    • Maximum output level of 10Volts RMS +20dB
    • Independent ground lift switches on the left and right Single Ended outputs
    • 1 set of Single Ended Cinema bypass outputs from input #1
  • Detailed Specifications
    • Frequency response 10Hz to 100Khz - 1dB with 10K Ohm load
    • Distortion ~ 0.02% at 1V RMS input
    • Gain 12dB
    • Signal to noise ~ 100dB below operating level
    • Non inverting output polarity
    • Cross talk >90dB
    • Front panel adjustable balance control
    • Remote control volume, mute and mono
    • Remote bypass switch on rear panel (just in case the remote is misplaced)
    • 1% metal film resisters throughout
    • Polypropylene capacitors throughout the audio path
  • Power
    • Power consumption 27W, 0 drain when off
    • Voltage 110/120V AC 60Hz
    • Optional factory installed 240V AC 50/60Hz
    • Standard 3 pin IEC power connector
    • ON/OFF power switch conveniently located on the side panel
    • Two internal high quality linear regulated power supplies, 250V and 12V
  • Active Components
    • Two (2) Gold pin JJ ECC83S/12AX7 vacuum tubes
    • Two (2) Gold pin JJ ECC82/12AU7 vacuum tubes
    • High quality ceramic sockets
  • Other Features
    • Each unit is hand made in the USA
    • 50 hour factory burn in on all circuits and vacuum tubes
    • Dimensions 17” W X 12” D X 5” H
    • Weight 23 lbs.
    • 16 gauge zinc plated steel enclosure
    • Award winning Isonode anti-vibration feet
    • Two year limited warranty
    • Six months warranty on Vacuum Tubes
    • Recessed RCA and XLR connectors are Gold plated with an isolated ground.
    • All switches and knobs are easily accessible, nothing hidden inside to adjust.

 

Bia 120 Class A Stereo Power Amp 

POWER WITHOUT COMPROMISE


 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

George Counnas's first amplifier design is finally here and it's receiving universal acclaim.  Bob Levi auditioned it in his system and found it to be revelatory, inspiring him to declare it to be the best he's yet heard - whether solid-state or tube:

I am flabbergasted. The more I listen to the BIA 120, the more I am certain this magnificent amplifier is the real McCoy! The BIA 120 is a state-of-the-art tube amplifier. The BIA 120 has superb clarity, depth, neutrality, realism, nuance, elegance, and ultimate definition that a great tube amplifier should have. It has the kind of snap, low distortion, freedom from noise and haze, tight fast bass, speed, and slam you would expect from great solid-state amps. It has none of the troublesome problems or sonic artifacts of either tube or solid state designs. It is neutral like no other tube amp has ever been in my experience. It is a wonder!

Zesto has created an amplifier that, when placed with the best ancillaries, will give you the experience of the musical performance with ground-breaking intense realism. The only things missing will be the sticky floors and the expensive tickets. I have never heard a better amplifier in my reference system, tube or solid-state. It is the best new tube amplifier to reach the market in the last five years priced under $50,000. That it costs $12,500 is a boon to audiophiles everywhere, and a minor miracle. What a value!  

- Bob Levi / Positive Feedback Online

About the Bia 120 Stereo Power Amp

Design Philosophy
With my pro background in the recording studio and live concert mixing, I wanted to build an amp that allowed me to hear music the way I know it should sound.

I wanted it to be easy to use, reliable and with plenty of power to drive the speakers. In short, I wanted power without compromising the music.

Class A Design
The tubes are always on, so you have power when you need it. Class A is fast and responsive. There is no lag, providing your music more punch, transient response, better dynamic range and transparency. 

Circuit Topology
I choose a Class A Ultra-linear, Push-Pull circuit design to deliver the most precise, enjoyable and faithful reproduction possible.

Unsung Hero
The unsung hero of a power amp is its power supply. That’s why my design incorporates a custom Toroid power transformer and a choke-based, dual-mono power supply–to deliver all the “slam” you can handle.

Easy to use
With Auto Bias, you need no adjustments. It’s safe, consistent and the settings are always perfect so you can enjoy your music. 

What is Bia?
In Greek mythology, Bia is the Titan Goddess of force and power.

Key Features

  • Plenty of power to drive your speakers
  • Pure Class A power is fast and musical
  • 4, 8 & 16 Ohm taps gives you options for your speaker preference
  • Dual Mono gives you less cross talk and better stereo imaging
  • No adjustments with Auto Bias. Its safe, consistent and settings are always perfect
  • Provides enough gain for most standard preamps and accommodate most speakers
  • Choice of either Single Ended RCA or Balanced XLR to suit your needs or cable preferences
  • Transformer balanced XLR input offers true noise rejection and isolation from the preamp
  • Left and Right ground switches work with the XLR balanced inputs to help eliminate ground hums
  • No Negative Feedback provides for virtually no compression to your music
  • Custom Toroid provides lower noise with plenty of available power
  • Global mains power supply can work all over the world
  • KT120 compatible
  • Push-Pull circuit design gives you more power
  • Ultra-Linear circuit design provides lower distortion
  • Low noise levels allow really dark black quiet musical passages
  • Non inverting polarity retains the same phase as the input (so your trumpets blow and don’t suck)
  • Gold pin sockets are more reliable because gold doesn't’t oxidize when it heat cycles
  • Matched quad output tubes retain the stereo balance
  • It’s ready to enjoy with 50 hours of factory burn in on all circuits and vacuum tubes.
  • Elegantly designed, heavy duty 14 &16 gauge zinc plated steel enclosure
  • Each unit is hand built "Made in the USA"
  • The wide frequency response allows you to hear the finest passages in your music.
  • High quality gold plated RCA, XLR connectors and 5 way binding posts
  • All fuses are easily accessible

Specifications

Output

  • Pure Class A
  • 60 Watts per channel
  • 4, 8 and 16 Ohm output taps
  • 8, 5 and 4 Amp Slow blow fuses for outputs
  • Eight 5 way binding post
  • Non inverting output polarity    
  • Push-Pull and Ultra-Linear design

Inputs

  • Transformer floating balanced XLR inputs
    Left and Right SE inputs with an impedance of 100K Ohms
  • Left and Right BAL inputs (pin 2 hot) with impedance of 12K Ohms
  • Independent ground lift switches on left and right BAL inputs
  • 2 Volts RMS input to reach rated output

Detailed Specs

  • Dual Mono
  • Auto bias
  • No negative feedback
  • Frequency response 20Hz to 50Khz  ~ 1dB
  • Total Harmonic Distortion ~ 0.22% at 1W output into 8 Ohms
  • Gain of 23dB
  • Noise level > 0.2 mV RMS into 8 Ohms with input shorted
  • 1% metal film resisters throughout
  • Polypropylene capacitors throughout the audio path

Power

  • Custom Toroidal power transformer with global mains
  • Choke based power supply design
  • 120 Volts AC mains
  • Optional factory installed 220V, 230V, 240V 50/60Hz
  • Power consumption at rated output 300 Watts
  • On/Off switch conveniently located on front panel
  • 3 pin IEC power connector with fuse

Active Components

  • Matched quad set of four (4) KT88’s vacuum tubes
  • Four (4) Gold pin ECC82s (12AU7) vacuum tubes
  • High quality gold plated ceramic sockets

Other Features

  • Each unit is made by hand
  • 50 hour factory burn in on all circuits and vacuum tubes
  • Dimensions 17" W X 20" D X 10 " H
  • Weight 66 lbs. (30Kg)
  • 16 and 14 gauge Zinc plated steel enclosure
  • Chrome steel spike feet