Cherry with natural anodized aluminium
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 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.
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 Duelund RS or CAST or possibly even using Tantalum film resistors, for example, these can be discussed at the point of ordering.
Maple with black anodized aluminium
Technical Specifications
Input Impedance
|
47 kOhm
|
Input Sensitivity
|
5mV for 1V Output
|
Gain
|
46 dBV
|
Output Impedance
|
<2 kOhm
|
Valve Compliment
|
2 x D3a
2 x EC8010
2 x 6BY5
|
Max. Power Consumption
| 70 Watts |
Unit Weight
| 19 kg |
Shipping Weight
|
30 kg
(Original Packaging: Customised flight case) |
Unit Dimensions
|
148mm (h) x 450mm (w) x 400mm (d)
|
Shipping Dimensions
|
240mm (h) x 545mm (w) x 500mm (d)
|
(Original Packaging: Customised flight case)
|
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.
Light Oak with natural anodized aluminium
Walnut with black anodized aluminium
Internal layout
