Single Ended Class-A Balance Preamplifier (Model: PA502A)

These preamplifier price is about 1/4 of the high-end for the brandname preamp, compare to the quality, circuit and parts, please discovering for this project by yourself.
I'd say this preamplifier is use the excellent circuite that designed by world class electronics simulating software(Circuit Maker) which can be adap or change every parts for the most benefit which can save the labor cost and time. The material also use the same grade as the high-end brand name use(just look at our Step attenuator then you'll see), also all are handmade with very good details skill by our staffs in Thailand ( assemble by our electrical engineer, not just a skill labor worker)

Well...by theory if I talk here will be more complicated to explain and long story but we'd like to tell you what interesting for this preamplifier will be easier to describe with understandable words as listed below:

-This preamplifer aim and build to reach the high-end by circuit design and material use

-MosFET Transistors (JFET) use for more sensitive with wide bandwidth

-This is a true class A type preamplifer (not a AB type or B type)

-Simple circuit yet have the excellent performance, why I dare to say this please continue to read the results below

-Plate true hole 2 sides circuit board, special made board type (not just a simple 2 sides circuite board)

-MosFET match pair technique




-Conenctor RCA and XLR for Input and Output type as a high-end standard

-Toriod Transfer for reduce noise

-Chooseable between balance or unbalance sources by mode switch (same with most hi-end preamp)
that becomes to these status:
1. Unbalnce input with balance output
2. Unbalnce input with balance output
3. Balance input with unbalance output
4. Balance input with unbalance output

-Volume control design to place at the end of circuit for:
1.more stable and balacing of signal
2.more accurate of fase-in and fase-out of the signal

-Step attenuator type as in the really high-end usage brand such as: Convergent, Sonic Frontier, Hovland...etc which these sell about $2000 and up.



-Hand-made of Step attenuator which use the resistor "Dale Resistor" brand, not a non brandname low loss resistor

-Cuicuite computerize design and simulate by "Circuite Maker" software

-This preamplifier we can sell as a kit with every parts, but it require skill to assemble.

-All technical questions or any comments about this preamplifier you can discuss with our team, we welcome for all questions and we can answer you all about this circuit, just write or email us.