Arcadia 18W PSE 300B Amplifier Repairs

An original Arcadia 18W PSE 300B amplifier has been in for servicing and repairs.

Originally supplied in 1997 it was enhanced with a large external dual-mono power supply in 2004.

Following a number of amendments, and a period of time in storage, it has been thoroughly repaired and serviced. A couple of damaged chokes have been replace, some of the psu capacitors replaced, a new pair of 6072A input and 5687WB driver valves, and a new set of EH Gold Grid 300Bs are now being used instead of the TJ mesh plate 300B/n valves shown.

The PSU contains a large mains transformer for each channel, plus valve rectifiers, choke input and first psu cap for the input/driver psu. The psu is remotely switched on/off from the main chassis.

Inside the main chassis there are two mains transformers for the 300B filament supplies, and six more chokes for the various power supplies.

In total there are three valve rectified, choke input filtered power supplies per channel, making six in total. One for the 300Bs, the second for the input/driver stage, and the third for the negative bias supply.

The components inside are typical of the period, including Elna Cerafine HT caps for the 300B ht, a lot of Black Gates, Hovland coupling caps, Mills and Rhopoint wirewound and even a couple of tantalum film resistors.

The servicing should see it good for many years to come.

Arcadia Model 7 Linestage Preamplifiers

It is two years since the first of the new SJS Arcadia Model 7 linestage preamplifiers were developed. 

During this time we have continued with research and development to further refine the musicality of the amplifiers, as well as offering both a Standard and Enhanced version of the design.

The Standard version has carbon film resistors and an RC couple gain stage:

The Enhanced version has tantalum film resistors, a choke loaded LC couple gain stage and enhanced psu choke:

Both versions feature 6111wa NOS military twin triode valves in the gain stage, Duelund Coherent Audio copper foil coupling capacitors, and the common SJS design elements:

• Single Ended circuit topology

• Pure Class A operation

• Zero negative feedback

• Valve rectification and choke-input HT power supply

• Custom made HT T-network power supply capacitors with silver leads

• Point-to-point circuit wiring without PCBs

• Hand built

• PTFE board for component mounting

• High quality components throughout

• Custom made aluminium chassis

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

SJS Arcadia amplifiers are available from Definitive Audio in Nottingham.

Munich High End 2018

This year marked the debut of SJS Electroacoustics Arcadia amplifiers at the Munich High End show, probably the largest high end audio trade fair in Europe.



Two SJS Arcadia Model 3 Enhanced MM phono stage amplifiers were present, one in the Living Voice room and the other in the Engström room.

The Living Voice room featured the Vox Olympian and Vox Elysium loudspeakers, partnered with vintage Kondo M77 and Gakuoh amplifiers. the vinyl front end was the Grand Prix Audio Monaco 2.0 turntable, with a Kuzma 4-point tonearm, and a Fuuga MC cartridge connected via a Living Voice step-up transformer to the Model 3 in oak with natural aluminium panels.



The Engström room featured the Vox Palladian & Palladiam Basso loudspeakers, partnered with Engström Monica and Lars pre and power amp combination, or the new Arne 300B integrated amplifier. The vinyl front end was a Kuzma Stabi M turntable, with Stogi S 12 VTA tonearm and Van den Hul MC catridge with a Kondo SFz step-up-transformers to the Model 3 in walnut with black aluminium panels.



Both Model 3 phono stages used in Munich were a customised version of the Enhanced Model 3. They were voiced in collaboration with Kevin Scott of Living Voice ahead of the show and feature NOS Shinkoh tantalum film resistors and Duelund Audio CAST copper coupling capacitors.

SJS Arcadia Model 3 phono amplifiers are available for demonstration at Definitive Audio in Nottingham, or here in Manchester.

Model 9 SUTs

Newly completed and ready for delivery, three SJS Model 9 SUTs, including:

• Hashimoto HM-7 transformers
• Pure silver wire with ptfe insulation
• Dual primaries can be switched for high/low impedance carts
• Ground connection on the primary can be isolated for floating the MC coils
• MuMetal lined aluminium casework
• WBT NexGen sockets and WBT silver loaded solder

The Hashimoto HM-7 transformers, which have dual primaries and may be switched in series or parallel, for matching medium (7 - 40 ohm) or low (2 - 7 ohm) impedance MC cartridges, providing gain of 15 times (23 dB) or 30 times (29 dB).

North West Audio Show 2017

WE ARE PLEASED TO ANNOUNCE WE WILL AGAIN BE EXHIBITING
AT THE NORTH WEST AUDIO SHOW ON 24 - 25TH JUNE 2017 

We are delighted to announce that we will again be exhibiting at the 4th edition of the NWAS which will take place in Cranage Hall and will run over 2 days.

THE SHOW

NWAS is set to become one of the highlights in the audiophile calendar. With great exhibitors, top brands and a superb venue, we believe that the North West Audio Show gives attendees the opportunity to hear the very best audio in surroundings that are second to none.

IT'S FREE

Free entry, free parking, a day surrounded by the best in audio and all in the beautiful setting of Cranage Hall, Cheshire. Book your free entry ticket(s) and enjoy a great audio festival at Cranage Hall in 2017 with best HiFi, live music, Audio Talks and more. Register and secure your free tickets today.

SJS Arcadia Model 7 Line Pre-amplifier

Following on from the successful launch of the Model 3 riaa, and the Model 5 power amp, SJS Electroacoustics are pleased to present the new Model 7 line stage pre-amplifier. The Model 7 has been designed as the 20th Anniversary re-imagination of the original Arcadia Model 1 line stage pre-amplifier, which was first delivered to customers in early 1997.

The Arcadia Model 7 line stage is based upon the same 6111wa NOS military valve 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
• Custom made HT T-network power supply capacitors with silver leads
• Point-to-point circuit wiring without PCBs
• Hand built
• PTFE board for component mounting
• High quality components throughout
• Custom made aluminium chassis

Design Options
The Model 7 line pre-amplifier is hand built to order in England, and therefore we are bale to offer customisation to meet your sonic preferences. Bespoke customisation of the internal components is possible to meet our clients' specific requirements, whether it is replacement of the Audyn capacitors with Duelund RS or CAST or possibly even using Tantalum film resistors, for example, these can be discussed at the point of ordering.

Technical Specifications

Input Impedance	100 kOhm
Gain	12 dB
Frequency Response	+/-3dB 3Hz-100KHz
Valve Compliment	2 x 6111WA 1 x EZ80
Max. Power Consumption	100 Watts
Unit Weight	10 kg
Shipping Weight	15 kg (Original Packaging)
Unit Dimensions	100mm (h) x 450mm (w) x 400mm (d)
Shipping Dimensions	180mm (h) x 545mm (w) x 500mm (d)
	(Original Packaging)

  

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

SJS Arcadia amplifiers are available from Definitive Audio in Nottingham.

Model 9 SUT

I have just finished this little project making up some nice MC step-up-transformers (SUTs) using the fantastic Hashimoto HM-7 transformers from Japan.

Hashimoto Electric have been making audio transformers since 1958 and was a transformer supplier to Sansui Electric until 1979 when they took over the entire Sansui transformer business, including patents, blue prints, designs and personnel.

Little known outside Japan until the past few years, their transformers are winning a lot of admirers, and the HM-7 MC stepup transformers have gained something of a reputation for outstanding performance.

The HM-7 has dual primaries which may be wired in series or parallel, for matching to medium (7 - 40 ohm) or low (2 - 7 ohm) impedance MC cartridges, providing a gain of 15 times (23 db) of 30 times (29 dB).

The lower cost HM-X has very similar specifications, and trades some low frequency performance for high frequency extension. The HM-3 model is almost half the cost of the HM-7, it offers 20 times (26 dB) or 40 times (32 dB) gain but has less high frequency extension than either the HM-X or HM-7.

The transformers are supplied in cans with solder connections, so they need to be built into a case for ease of use.

The switches on the left select series or parallel connection of the primaries, and the switch on the right connects or disconnects the primary winding ground to the secondary winding ground, to enable the primaries to "float".

Between the input and output phono sockets are a pair of "load" sockets, which can be used to plug in secondary loading resistors if desired.

The inside of the case is lined with mu-metal sheet to help minimise noise and hum pickup.

The finished SUT can be supplied with any of the three Hashimoto stepup transformers, HM-3, HM-X or HM-7 to best match with cartridge and budget.