We offer finished Mullard 3-3 type amplifiers which were designed in August 1955 by Mullard engineers, to show what could be done with single ended pentodes, an EF86 and EL84 with an EZ80 rectifier. The amplifier was never made commercially but could be built by the home constructor from the plans which Mullard provided.

Due to the resurgance in valve amplifier popularity, and their sonic ability, we are proud to offer a pair of finished and tested single ended mono - block power amplifiers based on this design. Our output transformer has three times the stack of M6 Grain oriented steel than the original models shown and gives a wider bandwidth than the original circuit and offers a sonic improvement in back to back tests. Review.

The amplifiers have a high sensitivity of 100mv for 3 watts output at 1% distortion (0.6% at 1 watt ).

You may be thinking will 3 watts drive my speakers ?

1) If a loudspeaker is rated at 85 dB/watt, a stereo pair each receiving 1 watt gives us 88dB. Two watts per speaker then gives 91dB.

2) Normal human speech is only 60dB. The notional figure of 100+dB is only required in a hall or auditorium so that a single voice can be heard by anyone when the hall is full.

3) The flat frequency response of 30 Hz to 30 kHz is wider than most loudspeakers can produce.

4) Output transformers remove DC offset which is inherent on a transistor amplifiers output, this DC current reduces the speaker efficiency by saturating the driver magnet and can be seen as the speaker cone moves at switch on !

Retail Price £ 750.00 per pair.

Payment terms Paypal or cheque

Dimensions: 205 (w) x 150 (d) x 165 (h) mm Wt: 3.35 kgs

F&S Transformers.

St. Margarets' Park - Main Entrance.

Pengam Road, Aberbargoed.

Mid Glamorgan. CF81 9FW.

Tel: 01443 - 833083.

E-mail: fstransformers@aol.co.uk

Please contact us for further information.

History of F&S Bio.

Other amplifiers in our range are the Audio Alliance 300B DC Axiom.

Push-pull EL84s'EL84.

and our Single ended 300B.