Sutherland Engineering DUO > Duel Mono Chassis > Phone Stage > Awarded: Stereophile Component of the Year / Class A  Recommended. 
I purchased this outstanding phono stage to go with the Brand New Rega Planer 8/Apheta 2 Cart combo but have decided to stick with digital so I am putting my analogue front end up for sale. 


If interested in Rega let me know and I will work out a package deal. 

PRODUCTS OF THE YEAR

Stereophile's Products of 2017 Joint Analog Components of the Year

Joint Analog Components of the Year

Sutherland Engineering Duo phono preamplifier ($4000/pair; reviewed by Brian Damkroger, September 2017, Vol.40 No.9 review)

Please look below for more items for sale as well.  
 
I still may want to set it up and use it if someone doesn't jump on it quickly but I just have so little time to use it. I have a newborn and been so busy at work. Maybe I will set it up properly next week if someone doesn't jump  on it? 

Please read my feedback and proceed with full confidence. This is a Fantastic value and I take care of my Audiogon Buyers! Much proven sale history to illustrate that.  

I ordered and bought all of this gear to fill out a full analogue front end but with my time constraint and my love for my Bricasti M1SE w/built in ethernet media player I think I will put it up on the Gon and see what happens.  

My impulse purchase will be a great benefit to someone!    

Sutherland Duo Phono Preamp

‘Music that I thought I knew very well consistently had new surprises for me’ – 10Audio

Testimonials (on all Sutherland Phono Preamps)

“The Duo comes very close to matching the PhonoBlock’s performance while costing $6,000 less per pair. I can’t recommend the Sutherland Duo more highly”
 – Brian Damkroger, Stereophile, Sept, 2017

“Music that I thought I knew very well consistently had new surprises for me… There are two important goals for phono stage performance: resolution and low distortion. The Sutherland DUO Phono Preamp excels at both.” Overall Rating 9.5 LPS (out of 10).
– Jerry Seigel, 10Audio.com

Overview

Sutherland Duo Phono Preamp

The Sutherland DUO two chassis Phono Preamp is derived from the cost no object Sutherland Phono Blocks and the cost-optimized Sutherland 20/20.

No expense was spared in the design and construction of the Phono Blocks. The Phono Blocks are at the pinnacle of Sutherland’s phono preamp performance. It just doesn’t get any better.

The one chassis Sutherland 20/20 was designed to get the most performance possible at its predetermined price point. To get there, extra was spent to get premium parts and circuitry into the signal path. Consequently, some expenses were squeezed out of less important areas. Those trade-offs have worked very well. The Sutherland 20/20 delivers an extremely high level of performance at a reasonable price. It is an incredible performance value.

What if all the price constraints in the 20/20 were lifted? The price goes up, the performance goes up. It starts looking a lot like the Sutherland Duo Phono Blocks.

The actual signal path of the Sutherland 20/20 is quite good. It uses a circuit very similar to the Phono Blocks. In critical positions, it also uses the same premium quality (and high cost) components. Very little was held back in that area.

The opportunity for upgrade is focused on a more refined power supply, improved circuit board properties and dual chassis construction.

Power supply discussion:

The 20/20 uses external, bench-top power supplies. They are cost effective, reliable and offer good performance. Each supplies output is extensively filtered and regulated into one +/- 15 volt source for both of the gain stages.

The Phono Blocks have built in AC power supplies. There is an IEC power inlet on each chassis to accommodate the user’s personal power cord choice. Two completely separate power sections (each providing isolated +/- 15 volts) are provided for each channel. One for each of the two gain stages. Each is independently filtered and regulated to provide the ultimate foundation for the gain stages.

Each Sutherland DUO Phono Preamp has a built in AC power supply. There is an IEC power inlet on each chassis to accommodate the user’s personal power cord choice. The shielded power supply module has one output. That output is split into two branches. One for each of the two gain stages. Each of those branches is independently filtered and regulated to provide a substantial foundation for the gain stages.

Circuit board properties:

Circuit board dielectric properties can introduce detail damaging artifacts into the signal,

The Sutherland DUO Phono Preamp mitigates circuit board dielectric properties using the same approach that has worked so well in the Phono Blocks. Circuit board thickness is doubled from the standard 1/16″ thickness to 1/8″ thickness. Not only is dielectric absorption addressed, but further advantages are realized with an extremity rigid platform for component mounting. It is the cost-no-object, preferred way to go.

The physics applied:

Anytime two conductors are at a different voltage potential, there is an electric field generated between them. The dielectric (the insulation between conductors) within that field become involved in charge storage. If not carefully considered, that extra charge storage can time smear details of a musical signal. Circuit board material is a dielectric. With normal double-sided construction, there are copper conductors on each side of the board. Unintentionally, a new capacitor is introduced into the circuit, formed by top surface copper, bottom surface copper and the circuit board dielectric sandwiched between the two. It is NOT the quality of capacitor we want to have in a high-end signal path. Some manufactures make the situation even worse by going to multi-layer boards in the analog audio sections. Instead of two layers of copper, there are four or more layers of copper. Even worse than that, the dielectric between layers is much thinner and the undesired capacitive effect is inversely proportional to thickness. At best, some manufactures make small, incremental improvements by using exotic board material.

The Duos addresses the issue of circuit board dielectric by doubling the thickness of an FR4 fiberglass circuit board. Just that one choice reduces electric field strength by one-half. Additionally, the area of copper interacting with board dielectric is also reduced in critical regions. Signal lines are kept narrow. Power lines are extremely wide. Such choices get us refined performance. Good solid advantages based up the application of good solid physics.

Dual chassis construction:

A sense of space and dimensionality is conveyed by the difference in the left and right channel information. To preserve those auditory clues, each channel must be isolated from the other and not spill over.

Both the Sutherland DUO Phono Preamp and the Sutherland Phono Blocks use a stack of two mono phono preamps for stereo. Absolutely nothing is shared between the left and right channels. Each channel is a completely free standing mono phono preamp. That is the ultimate in channel separation. The ultimate in spatial listening involvement.

PARTS QUALITY

FR-4 fiberglass circuit boards, Double-sided with plated thru holes. 1/8″ thick for extra rigidity and minimal dielectric influence.

Dale/Vishay 1% metal film resistors

Wima Polypropylene capacitors for power supply bypass and DC servo

Custom wound, 1% polystyrene film capacitors for equalization

14 gage cold rolled steel base

baked epoxy powder coat finish

1/2 ” thick anodized aluminum panel

anodized in front panel artwork

gold plated, Teflon insulated RCA connectors

gold plated configuration headers and shunts

Specifications

Gain Options

• 40 dB
• 46 dB
• 52 dB
• 58 dB
• 64 dB

Loading Options

• 47.5 k Ohm
• 1 k Ohms
• 475 Ohms
• 200 Ohms
• 100 Ohms

Size

• 17″ x 2 ½” x 12 each DUO
• 23 x 18 x 9 each DUO, packed in shipping box

Weight

• 11 lbs. each DUO
• 19 lbs each DUO, packed in shipping box

These other great items for sale as well.    
> Rega Planer 8 Turntable & Neo PSU > Rega Apheta 2 Cartridge > Full Acrylic Cover     Price $3,600.00

> Sutherland Engineering Duo Phono Stage: MSRP $4,200.00 -               Price $2,360.00

> Audioquest Fire Interconnects RCA 1.0M MSRP $3.000.00 -                Price $1,360.00  
. 
> Kubala-Sosna Emotion AC Cable 2.0M MSRP $2,450.00 -                 Price $860.00

> Audioquest Niagara 1000 AC Conditioner MSRP $1,000 -                 Price $760.00 


> Audioquest Tornado 1.0 Meter AC Power Cable MSRP $1,000 -               Price $660.00  


If you want a combo of the above items - let me know and I will cut you a nice deal. All are priced below actual value as is my custom but I will sweeten a combo deal of items.   

Two-Box Sutherland Duo MM/MC Phono Preamplifier a Marvel of Smart Engineering and Proven Physics: Super-Quiet, Ultra-Accurate Design Evades Dielectric Distress, Eliminates Crosstalk

At heart, the Stereophile Editors' Choice and Product of the Year Award-winning Sutherland Duo MM/MC phono preamplifier is a cross between the company's 20/20 and flagship PhonoBlock models. In practice, the two-chassis Duo serves as a knockout analog instrument in its price class – a U.S.A.-made component that borrows much of its design from a $10k cost-no-object product and delivers a level of musicality you will cherish for many years to come, if not forever. Detailed, natural, pure, dimensional, accurate, insightful: A few of the many positive sonic traits that will spring to mind once Duo enters your system and begins to help turn the information embedded in vinyl grooves into reach-out-and-touch-it aural experiences. Duo provides any listener fortunate to own it with superlative performance via perfectionist-minded focus and stunningly quiet operation. It all circles back to founder Ron Sutherland's emphasis on smart engineering and proven physics.

Duo's two-box layout automatically eliminates crosstalk, as each chassis gets its own circuit as well as its own built-in AC power supply and IEC power inlet. The shielded power supply module has one output split into two independently filtered and regulated branches – one for each of the gain stages. There's also more room for the internal parts, which benefits overall reliability. Each channel also features identical electrical and mechanical environments. Duo mitigates circuit-board dielectric properties in the same fashion as PhonoBlock. At twice the industry standard, each 1/8-inch-thick, double-sided FR-4 fiberglass board provides both needed absorption and extreme rigidity for component mounting. Once again, Sutherland refuses to compromise on any attribute. Just lift the cover and see.

Custom-wound 1% polystyrene film capacitors, Wima Polypropylene capacitors, Dale/Vishay 1% metal film resistors, gold-plated Teflon-insulated RCA connectors, and gold-plated configuration headers and shunts speak to the hand-picked quality within each box. Sutherland's trademark, ultra-clean housing – comprised of a 14-gauge cold-rolled steel base, baked epoxy powder-coat finish, and half-inch-thick anodized aluminum panel – complete a phono preamplifier more than prepared to be your daily (and dynamic) Duo. 

"The Duo is an incredible product. Ron Sutherland has once again raised his ratio of performance to price. Given the attention it deserves, it well become as much a classic as the original PhD. I can't recommend the Duo more highly."
– Brian Damkroger, Stereophile

How and Why Duo Skirts Dielectric Distress
Anytime two conductors are at a different voltage potential, an electric field is generated between them. The dielectric (the insulation between conductors) within that field becomes involved in charge storage. If not carefully considered, that extra charge storage can time smear details of a musical signal. Circuit board material is a dielectric. On normal double-sided construction, copper conductors are located on each side of the board. Unintentionally, a new capacitor is introduced into the circuit, formed by top surface copper, bottom surface copper, and the circuit board dielectric sandwiched between the two. It is not the quality of capacitor we want to have in a high-end signal path. Some manufacturers make the situation worse by going to multi-layer boards in the analog audio sections. Instead of two layers of copper, there are four or more. Even worse, the dielectric between layers is much thinner. The undesired capacitive effect is inversely proportional to thickness. At best, some manufacturers make small improvements by using exotic board material. Duo addresses the issue of circuit board dielectric by doubling the thickness of an FR4 fiberglass circuit board. That choice alone reduces electric field strength by one-half. Additionally, the area of copper interacting with board dielectric gets reduced in critical regions. Signal lines are kept narrow. Power lines are extremely wide. The result: refined performance. Good solid advantages based up the application of good solid physics

"It's measured performance reveals the Sutherland Duo to be a superbly quiet, superbly linear, and superbly accurate phono preamplifier."
– John Atkinson, Stereophile, 2017 Product of the Year

From Ron Sutherland:
"In the two-chassis designed Duo, there is the obvious elimination of crosstalk, as it's so much easier to design a mono circuit than one for stereo. Everything is simpler. There is more room to optimize the layout, which ends up improving reliability. Both channels here see identical electrical and mechanical environments, so there are less compromises in performance. Sometimes it actually costs more to optimize the performance of a single-chassis unit than it does to build another chassis and go with a mono circuit design."

These great products are located on the North Shore of Boston, MA. 

Please take some time to read my Feedback. It shows how I genuinely care about the other Audiogon members and the small group of other fellow audiophiles. I don't do this for a living but for me it's fun, it's my hobby. I buy some new gear and I am happy that there is a great place to either buy more or when it's time to sell and try some other gear. 

I take the greatest care of my items and I am offering a world class product for a great, well below market price. I am professional business person by trade and an audiophile by hobby and you can count on having a first class buying experience to go with some great top of the food chain Hi-Fi products .

I appreciate your taking the time to read my posting. Thank you for the time and consideration. Feel free to reach out if I can answer any questions. Shipping to be paid by the buyer and flat rate price is for continental USA 48 states only so please ask if you need to ship elsewhere. Only 3% for PayPal please. PayPal friends and family is Free… 

Thank You 

Fsmithjack