Pre-Amps - Reference Series

Model no: Reference-2
C$4,880 Untitled Document [US$ 3904]

6SL7/6SN7x 2 + 6550 x 2 + 274B fully balanced pure tube pre-amplifier

with tube direct and quad-core balanced transformer output + oil enhanced coupling capacitors + selectible choke filtering + headphone output + MDE


This model use the very common but dynamics and rich 6SL7 / 6SN7 as front end stage, gives you the most warm and liquid 3D holographic sound stage with superb micro-details . Output stage use the powerful 6550 (can also use VT52 / CV1052 / 6G6 / 6V6 / 6K6 / 6Y6 / 6F6 / 6L6 / 6550 / KT66 / KT77 / KT88 / KT99 / KT100 / KT120 / KT150 / EL34 / 5881 / 6CA7...etc direct plug-n-play ), which give superb dynamics sound with extremely good bass control . Rectifier tube use 274B (can also use 5U4G / 5AR4 / 5R4 / 53KU / GZ37 / STR-104 / STR-1001 / STR-1002 ...etc directly plug-n-play) matched with our special designed QUAD-core balanced output transformers and oil coupling capacitors , the mid and high is so silky smooth and syrup fluid, and the bass is very punchy with elastic tenderness control . All tube section built with point-to-point and component-to-component hand wiring technique to ensure max. transparency and natural tonal quality. Also equipped with filter choke for further musicality and smoothness enhancement, selectible with a selector for different music preferences. Constant current amplification ensure most stable sound stage with super high resolution. Our newest MDE (micro-dynamics extraction) circuit already included in this unit.

This is the second model of our Reference series of pre-amplifiers, which have no compromise in build quaility. All solid aluminum chassis. High headroom power transformer which is good enough to power up a push-pull amplifier, give exceptional reliability and stability as well as easiness of the sound with hanging in the air density. Our pre-amp designs are well know as giant killer. We strongly believe this pre-amp can easily surpass the sonic performance of competitors US$30,000-$60,000 offerings. The reason we are offering this pre-amp with such an unbelievible low price tag is simply because we can, and our goal is to clash the Titans.

For customer who need more artistic chassis design, we can offer all solid-oak chassis, or wood+AL chassis for your choices , additional cost may apply.

This pre-amp can use more than 9 x 20 x 10 = 1800+ different tube combinations to fine-tune the tonal quality as well as dynamics and richness, .

Non-feedback pure tube ORGANIC design with very open , smooth and sweet tonal quality. Those big output power tubes give exceptional richness and texture as well as super high density sound to regenerate the real live performance soundstage, which is never be reachable for products built with those smaller tubes like 6DJ8 / 12AX7 ...etc, no matter how much price they asked for.

You might wonder why it seems to be no others can make pre-amps with those big size tubes with ORGANIC design in order to achieve our superb level of sonic performance ? The answer is very simple , it is extremely difficult to design and build such a unit without putting any solid-state regulators and still come out with such professional grade performance. Most of the manufacturers are just aim at making a nice finished chassis , copy or modify from an old school circuit design, then throw in few small tubes and a few piece of well advertised capacitors on circuit boards , pay for some nice write-up review and advertisement, and expect a quick and big return from their investment , they are not dare or not capable to do such an extremely difficult design with those hired engineers / technicians, who even might not know what music is all about, but just follow the books.

Optional chassis :

Solid-oak side panels add $150

Solid-oak in regular lacqor finish add $250

Solid-oak in high gloss piano finish add $500

Black piano high gloss finish add $500


No. of inputs 1 set of XLR input + 2 sets of AUX inputs
No. of outputs

1 set of RCA output, 1 set of direct coupled XLR output , 1 set of quad-core balanced transformer coupled XLR output , 1 set of headphone output

Max. input level 3Vrms
Freq response Tube direct output 2Hz - 30KHZ (-3db) / Tx output 20Hz - 50Khz (-3db)
S/N > 90 db
Gain x3- x8 depend on tube types
manufacturing hand-wired point to point for tube section
Phase in-phase, non-inverted.
Input impedance 100Kohm

Default tubes :

Input stage (2 tubes) 6SL7 (alt: 6SN7, 6SU7, ECC32, ECC33, ECC35, 5691, 5692....etc)

Output stage (2 tubes) Tung-Sol 6550 (alt: VT52 / CV1052 / 6G6 / 6V6 / 6K6 / 6Y6 / 6F6 / 6L6 / 6550 / KT66 / KT77 / KT88 / KT99 / KT100 / KT120 / KT150 / KT170 / EL34 / 5881 / 6CA7...etc)

Rectifier 274B (alt:5U4G / 5AR4 / 5R4 / 53KU / GZ37 / STR-104 / STR-1001 / STR-1002...etc) with proper adapter can also use 80 / 83 / 8020 / 705A....etc


1 year free parts and labor warranty under normal operation condition, extend warranty possible with additional cost



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