using 3pcs Shuguang 12AU7 tubes. the cirult is very simple.but the analysis and Transient Capability are very good.sound very warm.
Input voltage: AC115V or AC230V for choose
Size:320*90*308mm (W*H*D)
Gain: about 6 times
Package include: Finished GG preamplifier X 1
Not include the AC input cable.
GROUNDED GRID vacuum tube pre-amp referred to as GG pre-amp, the original circuit from Transcendent Sound, the designer is the famous Bruce Rozenblit. Bruce has an extremely advanced skill in vacuum tube design, and excels in creating unique effects with simple circuits. He is one of the few masters in Europe and America who cross the DIY and HiEnd circles. His products are introduced by mainstream American audio media. Praise!
The grounded grid amplification stage is a very old circuit. Its gate grounding structure is actually evolved from a cascade architecture. The cascade architecture has a wide bandwidth, low distortion, high gain and very linear, which is exactly what all engineers dreamed of. It was originally used in telecommunication equipment and has even been forgotten by many designers. Its advantages are extremely high bandwidth, very low noise, and it is very linear. This sounds very appealing, and the bandwidth can be very flat from a few Hz up to 300 kHz. The voltage gain is set at 12dB, which is the majority of the previous stage settings, and distortion and noise are not all at all. The sound details and analytical power have reached or even surpassed some of the outstanding crystal pre-levels. The output internal resistance is as low as 300Ω, which is enough to push anything difficult to push. You can hardly overload it because it can output more than 20V RMS.
Shipping time:
Default send by fast express to US,CA，Mexico and most Europe, Asian countries，about 6-10 business days can arrived , Russia, Brazil,Africa.Ukraine and some other remote countries will send by china post, it will need about 30-40 working days.
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