FS: Minute Passive Preamp - SAC Thailand Transformer Volume Control (TVC)

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Item: SAC Thailand Transformer Volume Control (TVC)
Location: Sydney
Price: $800 (current replacement cost is $1100 plus shipping and 4% paypal fee)
Item Condition: As New
Reason for selling: Surplus to needs
Payment Method: Pickup - Cash, Paypal, COD Only
Extra Info:

 

I am selling this transformer volume control (TVC) from SAC Thailand on behalf of a good friend who is downsizing his audio system. This is a passive "preamp" with three inputs on RCA connectors and a single stereo output on RCA connectors. On the front panel one can select 0 dB or +6 dB of transformer gain. The input select and stepped attenuator are high quality Seiden switches from Japan. This unit uses the same transformers (OEM from SAC Thailand) as the highly regarded and extremely expensive Thrax Audio Dionysos.

 

A fantastic option between a DAC or CD player and a vacuum tube amplifier. Much more life and vitality than a resistor-type passive volume control and more transparent/lower noise floor than most active linestage preamps (tube or solid state).

 

Shipping costs to be borne by the purchaser. Collection from north-western Sydney is an available option.

 

 

Some information from the manufacturer:

 

Minute Passive Pre-Amplifier circumvents the above issues by utilizing transformer attenuation method that offers much higher impedance at +1 Megaohm range at 1KHz so at 2Vrms signal, the transformer will draw much less than 2uA of current (<0.002mA). +100 times less current drawn than resistor attenuator type. Another benefit of using transformer attenuation is its low DC resistance device at both input and output coils (in range of much less than 1 Kilo ohm). This low DCR characteristic forms easy path for noise or ghost voltage to bypass to signal ground. The figure is +10 times more effective than typical resistive element type passive attenuator. (dilemma to resistor attenuator is that it can't be chosen too low value since it will load the source and create unacceptable distortion & poor bandwidth, can't be chosen too high value since it will be inefficient to suppress induced noise)

 

Last but not least SILK STA-522A can amplify signal by doubling its output (+6dB function) to drive low sensitivity Power Amplifier which the resistor passive type could not do. Should there be a need to make phase correction in the out-of-phase audio systems, special arragement could be had for the phase inversion of signal modification since transformer can invert signal phase by just switching the coil arrangement (resistor could not do this).

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