Pre-Amps - Classic 100 Series

Model no:

QA-112-Mk3 (regular) C$1080 Untitled Document [US$ 864]

QA-112-Mk3 Super C$1380 [US$ 1104]

QA-112-Mk4 Super C$1780 [US$ 1424]

Mk3 Super Version (with IR remote volume control , 2 inptus, solid-oak side panels and enhanced power supply)

Mk4-Super version (with IR remote volume control, solid-oak side panels, BT5.0 receiver, 3 inputs and enhanced power supply)

Regular version (with 2 inputs and standard power supply)

pure tube organic line stage pre-amplifier with tube rectification

(Mk3 and Mk4 super version comes with remote volume and oil capacitors upgrade)

Mk4 version added bluetooth 5.0 receiver with further upgraded parts and power supply

Using the most common 6SL7/6SN7 tubes in the amplification section, this pre-amp is built with a 6X5 tube rectifier which gives you the best medium size tube sound with a low price. The sound is very liquid, dynamic, rich and warm with high definition. This is an all hand-wired state-of-the-art pre-amplifier. This pre-amp also inplimented our famous component-to-component and point-to-point hand wiring technique, as well as our non-feedback organic pure tube sinigle-ended class A design, it can gives you exceptional super natural and open airy sound stage which other manufacturers no way to compete with.

We strongly believe the sonic performance of this unit easily surpass those products selling over US$ 6-8K in the audio industy

This pre-amp can use more than 10 different models of tubes (ECC35,ECC32,ECC33,6SN7,6SU7,6188,6SN7,6SL7,6SU7,5691,5692...etc) to fine-tune the tonal quality as well as dynamics and richness, with additional tube expansion adapters, even can use 6L6, 6K6, 6G6, 6V6, 6F6, 6Y6,KT66,6550, EL34, 5881, KT88, KT99, KT100...etc ( only possible with Enhanced or Super version, and one of the tube in the adapter must be 6G6G)

The 6X5 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 2 sets of RCA inputs (CD / AUX)
No. of outputs 2 setsof pre-amp outputs
Freq response 5Hz - 150Khz (-3db)
S/N better than 85 db
Input impedance 82Kohm (option: from 10Kohm to 1Mohm)
Gain x3 - x6 depending on tubes
Phase 180deg inverted (option: non-inverted)
manufacturing hand-wired point to point
Tubes 2 x 6SL7 (option: ECC35/ECC32/ECC33/6SN7/6SU7/6188/5691/5692..etc) + 6X5

(Note: The upgrade price below is a special deal for new orders only, modification of previously built unit will be around $300 higher than the following prices due to more works needed 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.

Additonal up-grade options:

0/180deg output phase selector add C$150

solid-oak chassis add C$200

solid-wood side panel add $80


1 year free parts and labor warranty under normal operation condition
standard chassis : Gold/ Black/Metallic MDF , Aluminum chassis

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

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