Hafler TRANSANA TRM10S - Manual (Page 11)

MEHSA
(Maximum Efficiency HeatSink Application) MEHSA is a proprietary process that yields up to 5 times better heat transfer
than traditional FET mounting techniques using the exact same components. A multi-layer insulated metal substrate
operating with minimal thermal resistance spreads heat both downward and outward to quickly dissipate heat from
each device across the heatsink. This process combined with our DSM technology and MOSFET devices allows us to
squeeze more watts per cubic inch from every output device as well as provide consistent thermal stability.
THE RESULT: Better reliability through faster heat dissipation.
Trans• ana
Trans• ana (TRANSconductance Active Nodal Amplifier) is a circuit that allows the audio signal to pass through the
amplifier at low voltage. The signal is directly level-shifted to the fixed high voltage rails via a pair of driver transistors.
Signal linearity is assured by an active node formed by the driver transistors at ultrasonic frequencies. This allows
amplifier performance similar to Trans•
nova which is highly stable and linear while utilizing the advantages of a non-
floating power supply.
THE RESULT: An extended frequency band width accurately supplied to the output stages of the amplifier.
MOSFET Devices
HAFLER is one of the few manufacturers in the sound community to utilize MOSFET devices in both the power supply
and output stages. MOSFET (Metal Oxide Semiconductor Field Effect Transistor) devices offer several important
inherent advantages over the 30 year old technology of bi-polar design. These advantages include: thermal stability,
fast switching speed, ultra low output impedance and wide bandwidth linearity. In addition, MOSFETs operate very
similarly to vacuum tubes in that they are more linear than bipolar transistors. However, MOSFETs can deliver the
midrange clarity without the limitations of transient response and high frequency phase shifting normally associated
with tube operation.
THE RESULT: Thermal stability, fast switching speed, ultra low output impedance and wide bandwidth
linearity.
– 2 –
®
Amplifier
®
®
Clamp Bar
Heat generating component
(typically a power MOSFET or
bipolar semiconductor)
Thermal grease
Mica
Thermal grease
Heat sink
Screw
Heat path
PC Board
Heat Monster:
High output MOSFET device
Solder
Copper heat spreader
Dielectric layer
Base Layer - aluminum
Thermal grease
Heat sink
Screw, no pressure on component!
Multiple heat paths PC Board
The Old Way The Way