Pre-Amps - Classic 100 Series

Model no:   QA-115-Mk2 / QA-115-Crystal
C$2,080 Untitled Document [US$ 1664] (regular ver.) / C$2,680 [US$ 2144] (crystal ver.)

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line stage full balanced pre-amplifier

Using the 6SL7/6SN7 tubes as the amplification, and 6L6G tubes as the output buffer section, this unit is also built with a 5U4G tube rectifier and enhanced power supply, (which gives you the best price-performance in a fully balanced pre-amplifier). All hand-wired to the highest possible standard. With the flexible capability of over 600 different tube combinations, you can easily fine-tune the tonal quality of this pre-amp to adapt it to the rest of your system.

This pre-amplifier has a special Normal/fast feature switch, it can give you a very high adaptability to different types of music. The Fast position is good for Rock, Pop and Jazz, while the Normal position is good for Blues, Vocal and Classical music. Even though this switch can change the pace of the music reproduction, the alternation can't be detected by any existing measuring instrument. The specifications will not be altered, the changes are only detectable by the human ear.

Top photos are the new CRYSTAL version (silver solid aluminum + clear plexiglass design with oil capacitors upgrade, $2,680 only !! )

The 3nd lowest set of photos shows a standard version with an additional silver aluminum face plate.

Lowest photo set shows solid-oak chassis with color aluminum top panel

Now available are super rectifier tubes up-grade STR-104 , STR-1001 and STR-1002, which can greatly enhance the dynamics, high and low frequency extension, and bass punch. A stand-by switch for pre-heating of the rectifier tubes ensures the longest operation for the lifetime of the tube. Rectifier tubes are replacable with high quality ceramic sockets installed.

STR-104 super rectifier $880

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 and 1 set of XLR balanced inputs
No. of outputs 1 set of RCA and 1 XLR balanced pre-amp outputs , 1 set of record outputs
Freq response 1Hz - 150Khz (-3db)
S/N > 85 db
Input impedance 68Kohm (option: from 10Kohm to 1Mohm)
Gain x3- x8 depend on tubes
Phase 180deg inverted (option: non-inverted)
manufacturing hand-wired point to point

2 x 6SL7(Alt: 6SN7/6SU7/ECC32/ECC33/ECC35/6188 or equiv)

+ 2x 6L6G (Alt: 6V6/6K6/6G6/6F6/EL34/5881/6550/KT66/KT88/KT99/KT100 or equiv )

+ 5U4G (option:5AR4/5V4G/5R4/274B/53KU/STR-101/STR-104/STR1001/STR-1002)

(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.

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.


add 0/180 deg phase control switch with additional of C$150

Sold-oak chassis add C$250

Top aluminum panel add C$50

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

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

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