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AST-5881sSTK Vacuum Tube Stereo Single Power Amplifier

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AST-5881sSTK Vacuum Tube Stereo Single Power Amplifier

Regular price $1,396.00 USD
Regular price $1,642.00 USD Sale price $1,396.00 USD
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Limited quantity. Special price! Don't miss this opportunity!

This product is made to order. Delivery time is 7~10 days. Overseas specifications may take 3~4 weeks to ship due to transformer manufacturing and other reasons.

Enjoyable for everyone from beginners to veterans of tube audio

Faithful reproduction of the original sound source


Astro Electronic Planning, a manufacturer of vacuum tube amplifiers, has created a new series for beginners in vacuum tube audio. By narrowing the width and reducing the size of the amplifiers, they are lighter and easier to handle, and AST's STK series uses the company's first original internal circuit board to simplify manufacturing and reduce production costs and time.

Astro Electronics' original circuit boards are designed with thicker wiring than normal circuit boards, which contributes to the amount of information and sound quality. Also, by using the company's original high-quality products for all transformers, we have succeeded in keeping the price low without sacrificing sound quality. By carefully crafting each tube amplifier one by one, our tube amp craftsmen have created a sound quality with expression and power that will satisfy not only beginners but also enthusiasts.

There are two inputs, and music players such as CDs can be connected directly without a preamplifier to enjoy authentic vacuum tube sound. In addition, LEDs are installed in the tube inserts to provide a new visual effect of tube amplifiers.

The output tube has a self-bias function, so you can easily replace it with a compatible bulb and enjoy. The self-bias capacitor used in the AST-5881sSTK has a higher capacitance of 470 microns, compared to the 100-200 microns used in most amplifiers in the same price range. This allows the sound to be expressed well even when the volume is turned down. Since it has independent left and right volume controls, it can be connected directly to CD players, smartphones, tablets, and other devices to enjoy high-quality tube music without a preamplifier.

Tubes used
5881×2  12AX7 x 2
Transformer used
Output 2W x 2W, self-biased
Frequency Response
Residual Noise Less than 1mmV/1W
Input impedance
A100KSpecial custom substrate circuit used
Power supply 100V / 50,60Hz
Size W270 x H150 x D300mm
Weight Approx. 5kg