Pre-Amps - Classic 100 Series

Model no: QA-111-BAL-SP-Mk2
C$1,980 Direct Order Price

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line stage balanced input and output pre-amplifier with super low output impedance

This model uses the most common 6DJ8 / 6922 in the pre-amp section. This architecture gives you the best fully balanced small tube sound with a low price.

The output impedance is so low it can drive any 600ohm input impedance power amplifier without any problem.

For a traditional balanced design, you must have both the input and output balanced in order to get the added boost in performance of balanced amplification. With our new state-of-the-art design this limitation no longer exists. This means you can use either the balanced input or output, and still have the sonic improvement of balanced amplification. (About a 70% improvement which only input + output balanced amplification can achieve).

The lowest photo set shows a special version equipped with a bigger transformer and big tube rectifier.

The 5U4G tube rectifier can further upgrade by our super rectifier STR-104 or higher models , direct plug and play without any mod required.

With this super rectifier adaptor, you can use 300B, 2A3 , 45 , 50 , 80, 83, 1616 , 3B28 or 866A as rectifier tubes option.

No. of inputs 1 set of RCA inputs, 1 set of balanced inputs
No. of outputs 1 set of RCA and XLR balanced outputs , 1set of record outputs
Freq response 1Hz - 150Khz (-3db)
S/N better than 85db
Input impedance 68Kohm (option: from 10Kohm to 1Mohm)
Gain x5-x10 depending on the gain of the tubes
Phase 180deg inverted (option: non-inverted)
manufacturing hand-wired point to point
Tubes 6 x 6DJ8/ 6922

(Note: The price quoted is a special deal for newly order unit only, modification of existing unit will be around $300 higher than the following prices due to more works for disassemble of the original circuits)

Level 1 upgrade : (+ C$200)

Special designed "Super-Drive" circuit, output impedance lowered to 200ohm (can drive any power amp inputs from 600ohm up to infinity) with better bass control and punch , better definition and improved in overall tonal quality. By adding this upgrade, it sounds like the output with 10 pieces of power tubes being installed . With this level of upgrade, just add another $50 and you can have a headphone output with enough power and current to drive your headphone directly.

Level 2 upgrade : (+ C$500)

Level 1 upgrade + Enhanced input circuit design with increase of max. input levels , further lowering of distortion and increase dynamics, as well as better air and openness . Enhanced components quality for better sonic reproductions with higher resoltuions.

Level 3 upgrade : (+ C$800)

Level 1&2 upgrade + Upgrade power supply with bigger transformer and stronger filtering circuit as well as enhancement in components for further sonic enhancement with more 3D holographics soundstage.

Level 4 upgrade : (+ C$1000)

Level 1&2&3 upgrade + Enhanced transformer with 5U4G tube rectifier for better air , smoother and sweeter sound quality


1 year parts and labor warranty under normal operation conditions

Additonal up-grade options:

0/180deg output phase selector add C$150

solid-oak chassis add C$150

standard chassis : Gold/ Black/Metallic MDF , Aluminum chassis

(optional chassis : Mirror steel, solid-oak, black piano )

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