Mal Valve
D. Mallach
Towersgarten 11
45239 Essen

Tel +49-(0)201-408084




Power Transformer Mk 6

loudspeaker power transformer


Design *Construction

· strip-wound core transformer
· lower inner resistance for best impulse processing
· big magnetic core of 2.500 VA
· transformer coils encapsulated for better coupling
· separate coils per impedance for best transmission characteristics
· completely passive operation
· best rectangle behaviour and wide frequency response
· placeable near to the loudspeakers and therefore shorter loudspeaker cable ways
· for all power amplifiers and passive loudspeakers


· gold plated pole terminal
· gold plated 4 mm sockets


· inputs
· outputs
· efficiency
· loading capacity

8 to 1 Ohm
8-7-6-5-4-3.5-3-2.5-2-1.5-1 Ohm      
> 98 %
> 500 W


Trasnformer housing

· 10 mm aluminum chassis brushed and black or natural anodized
· transformer moulded in synthetic resin

· dimensions:  2 x Ø 250 x 240 mm
· weight: 30 kg


Possibilities of usage

· Optimization of the adjustment of amplifiers and loudspeakers
· power adjustment of lower and higher Ohm amplifiers, i.e.. OTL-tube amplifier and transistor amplifier
· power adjustment of lower and higher Ohm loudspeakers, i.e. electro states and magneto states
· electrostatic seperated loudspeaker chassis for bass, mid- and high range levels sepereately adjustable
· better adjustment to the room acoustic
· moving of the amplifiers operation range in the A-mode
· impedance transformation, level transformation and A-mode combinable
· connectors can be occupied multiple times

Configuration * Adjustments

impedance transformation

The impedance transformation allows to adjust the loudspeaker to the amplifier at its optimum.
The impedances of amplifiers and loudspeakers attune only in exceptional cases, especially as the impedance of most loudspeakers is changing frequency-dependent. Even if the amplifier has equal connections for different output impedances (i.e. 8 + 4 Ohm), the steps are nomally too rough for reaching a best possible impedance adjustment.

Impedance downward transformation

· optimal adjustment in full range mode of the loudspeaker impedance
· use the 8-Ohm input as input, also at amplifier input impedances above 8 Ohm (i.e. OTL- tube amplifiers)
· use the higher equivalent output for amplifiers with output transformers


Impedance upward transformation

· optimal adjustment in full range mode of the loudspeaker impedance
· Input is the connection, that conforms the impedance optimum of the amplifier or amplifier with output transformer.
· Use the higher quality output at amplifiers with output transformers.



Level transformation at electrically seperated loudspeaker chassis

· for optimizing the loudspeaker frequency response
· for better adaption of the loudspeaker to the room acoustic
· for better adjustment of the audio system configuration
· the higher the connection value to the loudspeakers, the higher the volume




A – operation/mode

. for switching the operation range of the Malvale power amplifiers into the A-mode by over-adjusting the loudspeaker impedance
· for reaching the best sound result at a comfortable output power