Reference Vacuum Tube Line Stage


Magnetostat is a new reference point line stage made by NAT standards – transformer coupled pure triode class A with absolute zero feedback circuit configuration.

Military grade type 6N30P-DR output tube is used - represent high technology in vacuum tube manufacturing.

Both tubes are also by N.O.S. (new old stock) grade and have high reliability.

Construction of output tube 6N30P-DR is very robust also in mechanical domain – means there is no high level of microphonic effect for negative influence to the sound reproduction.

Hand crafted wide-bandwidth output transformer (custom designed for NAT ) is used in this unit.

Output transformer contain no less then 61 separate different material layers. Bandwidth is from 2.5Hz – 160.000Hz. That is extremely good result for high direct current single ended transformer coupled operation mode. Total weight of transformer for one channel is approx. 8kg. Output has separate tap for single ended and balanced operation!

By specific technical approach mention output transformer in combination with single output tube may drive easy any type of interconnect even long length cable.

Absolute zero feedback concept is well known also as the best solution for purity of sound reproduction without negative influence from feedback circuit. There is no any capacitor on direct or indirect signal path. 

Attenuation is based on high reliability relay (pure silver with gold plated contacts) network that is computer controlled – there is 96 position of attenuation and always is only one (single) laboratory grade resistor on signal path.  

Magnetostat is equipped with basic function remote control unit made from solid block of aluminum. 

Power supply section also speaks for itself. High capacity battery supply is used as the best solution for power section.

There are separate voltage regulators also for all additional (non signal path) stages.

On such a way sound quality is totally independent from line voltage instability and influence of wide variety noise that could be coupled across.

Also second toroidal type transformer supply digital circuit that control non analog signal preamplifiers function. 

There is a built-in measurement for total hours of tube life accumulated that is presented by led diodes universal Meter. 

Quality of electronic material that is used inside Magnetostat is impressive - tubes by military and N.O.S. grade standard, 0.1% Vishay resistors, high quality transformer core, electrolytic capacitors for 105C of working temperature, gold plated Teflon isolated connectors, pure silver input wiring…

Line stage works properly at all world wide AC line voltage from 100 – 250 VAC, 50-60Hz (different transformers are used).

 

   
 
Technical Specification

Type

Absolute Zero Feedback Triode

Operation

Single-ended (RCA) or balanced (XLR)

Frequency Response

2.5 to 160 kHz, -3 dB; 20Hz to 20kHz, +/-0,1dB 

Noise

90 dB IHF reference to 1V

Gain

12 dB (X 4) RCA output 

THD & N <0.1 %

Input Impedance

>20 kohms

Output Impedance <50 ohms–RCA or XLR output :600 ohms balanced compatible
Stereo Separation >95 dB @ 10 kHz

Tube Complement

 2 x 6N30P-DR per unit, special selection (1:20 filtrated)

Output Impedance

<50 ohms–RCA or XLR output :600 ohms balanced compatible

Power Requirements

110 VAC or 220 VAC @ 50 to 60 Hz, max. 50 VA

Dimensions

19" (483 mm) wide , 21.6" (550 mm) deep , 7.1" (180 mm) high (max.dimensions)

NET Weight

approx. 110 lb. (50 kg) unpacked

TOTAL Weight

approx. 140 lb. (63 kg) packed in wooden box

Design Features

- transformer coupled circuit (without any capacitor on direct or indirect signal path)
- absolute zero feedback design
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automatic recharge function
-
custom designed wide-bandwidth encapsulated output transformers
-
full balanced stabilisations for tube heaters and other purposes
- two 6N30P-DR special selected tubes (NOS) in amplification section – one per channel
-
two additional separate transformers for digital control and recharge function
-
attenuation network form silent reed relay – encoder rotation knob type
- remote control made from solid block of aluminium
- all aluminium modulated chassis that includes 5mm thick also aluminium top cover
-
built-in measurement for total hours of tube life accumulated
- teflon insulated gold plated connectors  
-
gold plated teflon insulated RCA jacks with gold plated XLR balanced connectors
-
hand assembled all aluminum modulated chassis
-
laser engraved front panel made from triple separate aluminum block of 20mm thick
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laser engraved remote control made from solid block of aluminum
- extensively used computer numeric control machines (CNC)



Specifications are subject of change without notice