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View Full Version : SJS Arcadia Model 3 Valve MM Phono Amplifier



sjs
21-07-2015, 09:46
Approximately 15 years since the Arcadia Model 1 and Model 2 line stage preamplifiers ceased production, SJS Electroacoustics are pleased to present the all new bespoke Arcadia Model 3 all valve moving magnet RIAA phono amplifier.

https://dl.dropboxusercontent.com/u/30444544/SJS/Cherry-Alu-Front.jpg

It represents a modern extension of the design philosophy behind the original SJS Arcadia amplifiers and has been specifically engineered for sonic performance rather than technical specification, and fulfils all SJS Electroacoustics primary design criteria:


Single Ended circuit topology
Pure Class A operation
Zero negative feedback
Valve rectification and choke-input HT power supply
HT power supply without electrolytic capacitors
Custom made HT T-network power supply capacitors with silver leads
Separate mains transformers for HT and filament supplies
Point-to-point circuit wiring without PCBs
Hand built
PTFE board for component mounting
NOS Hovland MusiCap coupling capacitors
Low resistance RIAA network using MusiCap film/foil capacitors
Real solid wooden frame
4mm aluminium panels, black or natural anodized
Soundcare SuperSpiked feet


The Arcadia Model 3 Moving Magnet phono stage uses a triode-wired D3a common cathode valve for the input stage, to provide high gain, excellent linearity, high overload margin and exceptional transient response. This drives the low impedance resistor-capacitor (RC) passive RIAA filter, with a high gain EC8010 valve as the output stage.

The detrimental effects of electrolytic capacitors in the audio circuit are avoided by utilising custom designed and made film capacitors in the power supply, with each gain stage having its own choke-capacitor filtered branch of the supply. This approach extends to the audio circuit where the use of electrolytic capacitors for cathode bypass has been avoided by running the first stage biased with a SiC diode, and the second stage using fixed battery bias on the grid. These design solutions deliver a dynamic fast and clean presentation, whist preserving the tone, clarity and effortless grace of a good valve amplifier.

The avoidance of a cathode follower output stage provides a significant benefit to the musical delivery of the unit, however it does mean that it is not a universally applicable phono amplifier and for optimum performance has been designed to be used in a system where the following preamplifier stage has an input impedance of 100 kOhm. It may be used in systems where the following preamplifier stage has an input impedance as low as 20 kOhm however there is likely to be a reduction in bass performance in this case. If there is a desire to use the unit with a load below 100 kOhm on a long term basis, it may advisable to discuss having the unit customised to suite with SJS Electroacoustics directly.

https://dl.dropboxusercontent.com/u/30444544/SJS/Maple-Black-Rear.jpg

Design Options
The Model 3 valve MM phono amplifier is hand built to order in England, and therefore we are able to offer customisation to meet your aesthetic and sonic preferences. the solid wooden chassis is available in a range of four standard choices; cherry, maple, light oak and walnut with others such as zebra wood available to special order. The chassis panels are available in either natural or black anodised aluminium as standard, with other colours, such as blue, red or gold, available to special order.

https://dl.dropboxusercontent.com/u/30444544/SJS/Oak-Alu-Front.jpg

Bespoke customisation of the internal components is also possible to meet our clients' specific requirements, whether it be for use of a certain interconnect cable between the phono sockets and the circuit, or replacement of the NOS Hovland MusiCaps with Dueland RS or CAST or possibly even using Tantalum film resistors, for example, these can be discussed at the point of ordering.

https://dl.dropboxusercontent.com/u/30444544/SJS/Walnut-Black-Rear.jpg

https://dl.dropboxusercontent.com/u/30444544/SJS/Phono-inside1.jpg

Each amplifier comes with 2 years parts a labour warranty, except for the valves which have a 6 month warranty.

Further details can be found on the SJS Blog (http://sjselectroacoustics.blogspot.co.uk/)

vegman1973
22-07-2015, 14:59
Beautiful! [emoji7]

sjs
28-07-2015, 09:14
Beautiful! [emoji7]

Many thanks.

Demo units are available for a listen here in Manchester, or by arrangement in your own home.

vegman1973
28-07-2015, 19:34
I don't think my Rega P6 would do it justice? But would love to hear it

Mike Adams
04-11-2016, 21:58
Simon kindly has sorted my BP P20…which is now sounding fantastic.
I’ve then borrowed one of these.
It’s very revealing, with great tone and works flawlessly. I’ve tried most of the latest and greatest and this is a cut above…

sjs
20-01-2017, 12:53
Three Premier versions of the SJS Model 3 MM phono amplifiers almost ready to go.

Upgrades over the Standard version include:

C-core chokes
Dueland CAST coupling capacitors
Dueland Alexander RIAA capacitors
Tantalum resistors
Silver cable throughout



https://dl.dropboxusercontent.com/u/30444544/SJS/Model3_Premier.jpg

Chassis used are Cherry, Oak and Maple

sjs
20-04-2017, 14:05
To celebrate 20 years since the first sjs arcadia Model 1 preamplifiers were delivered, we are pleased to announce a special 20th anniversary 20% discount on confirmed orders for any new sjs arcadia valve amplifier

https://dl.dropboxusercontent.com/u/30444544/SJS/Arcadia%20-%2020th%20anniversary%2020%25%20offer.jpg

This offer includes all current designs: Model 3 riaa, Model 5 se 300B, Model 6 riaa, Model 7 line, Model 8 se 300B amp, Aoide headphone amp

sjs
15-09-2017, 17:16
Approximately 15 years since the Arcadia Model 1 and Model 2 line stage preamplifiers ceased production, SJS Electroacoustics are pleased to present the all new bespoke Arcadia Model 3 all valve moving magnet RIAA phono amplifier.

https://dl.dropboxusercontent.com/s/f0u0ext8u77ojf6/Cherry-Alu-Front.jpg


It represents a modern extension of the design philosophy behind the original SJS Arcadia amplifiers and has been specifically engineered for sonic performance rather than technical specification, and fulfils all SJS Electroacoustics primary design criteria:


Single Ended circuit topology
Pure Class A operation
Zero negative feedback
Valve rectification and choke-input HT power supply
HT power supply without electrolytic capacitors
Custom made HT T-network power supply capacitors with silver leads
Separate mains transformers for HT and filament supplies
Point-to-point circuit wiring without PCBs
Hand built
PTFE board for component mounting
NOS Hovland MusiCap coupling capacitors
Low resistance RIAA network using MusiCap film/foil capacitors
Real solid wooden frame
4mm aluminium panels, black or natural anodized
Soundcare SuperSpiked feet


The Arcadia Model 3 Moving Magnet phono stage uses a triode-wired D3a common cathode valve for the input stage, to provide high gain, excellent linearity, high overload margin and exceptional transient response. This drives the low impedance resistor-capacitor (RC) passive RIAA filter, with a high gain EC8010 valve as the output stage.

The detrimental effects of electrolytic capacitors in the audio circuit are avoided by utilising custom designed and made film capacitors in the power supply, with each gain stage having its own choke-capacitor filtered branch of the supply. This approach extends to the audio circuit where the use of electrolytic capacitors for cathode bypass has been avoided by running the first stage biased with a SiC diode, and the second stage using fixed battery bias on the grid. These design solutions deliver a dynamic fast and clean presentation, whist preserving the tone, clarity and effortless grace of a good valve amplifier.

The avoidance of a cathode follower output stage provides a significant benefit to the musical delivery of the unit, however it does mean that it is not a universally applicable phono amplifier and for optimum performance has been designed to be used in a system where the following preamplifier stage has an input impedance of 100 kOhm. It may be used in systems where the following preamplifier stage has an input impedance as low as 20 kOhm however there is likely to be a reduction in bass performance in this case. If there is a desire to use the unit with a load below 100 kOhm on a long term basis, it may advisable to discuss having the unit customised to suite with SJS Electroacoustics directly.

https://dl.dropboxusercontent.com/s/rfz6d7rzxjqdq1f/Maple-Black-Rear.jpg

Design Options
The Model 3 valve MM phono amplifier is hand built to order in England, and therefore we are able to offer customisation to meet your aesthetic and sonic preferences. the solid wooden chassis is available in a range of four standard choices; cherry, maple, light oak and walnut with others such as zebra wood available to special order. The chassis panels are available in either natural or black anodised aluminium as standard, with other colours, such as blue, red or gold, available to special order.

https://dl.dropboxusercontent.com/s/xbeomptu6h8r780/Oak-Alu-Front.jpg

Bespoke customisation of the internal components is also possible to meet our clients' specific requirements, whether it be for use of a certain interconnect cable between the phono sockets and the circuit, or replacement of the NOS Hovland MusiCaps with Dueland RS or CAST or possibly even using Tantalum film resistors, for example, these can be discussed at the point of ordering.

https://dl.dropboxusercontent.com/s/puuf7gerie35fk0/Walnut-Black-Rear.jpg

https://dl.dropboxusercontent.com/s/puuf7gerie35fk0/Walnut-Black-Rear.jpg

Each amplifier comes with 2 years parts a labour warranty, except for the valves which have a 6 month warranty.

Further details can be found on the SJS Blog (http://sjselectroacoustics.blogspot.co.uk/)

SJS Arcadia amplifiers are available from Definitive Audio (http://www.definitiveaudio.co.uk/news.html) in Nottingham

sjs
28-01-2018, 19:56
a couple of demo units are available, get in touch if you want a home demo