{"product_id":"astro-ast-eq50gzmg-tube-phono-equalizer","title":"ASTOR AST-EQ50GZMg Vacuum Tube Phono Equalizer Amplifier","description":"\u003cdiv class=\"post-shipping-info\"\u003e\n\u003cmeta charset=\"utf-8\"\u003e \u003cspan\u003eThis is a special sale item available while supplies last. It is only available in 100V specification. Due to the difficulty in continuing the brand, there is no manufacturer warranty or manufacturer repair.\u003c\/span\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"products-eyecatch\"\u003e\n\u003ch2\u003eChoose vacuum tubes for the core of record playback.\u003c\/h2\u003e\n\u003ch3\u003eEquipped with two PHONO inputs, this vacuum tube phono equalizer carefully renders everything from the outlines of the sound to delicate reverberations.\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"products-desc-title\"\u003eDescription\u003c\/div\u003e\n\u003cdiv style=\"text-align: start;\"\u003e\n\u003ch3\u003e\u003cstrong\u003eHigh-Quality Phono Equalizer Using Vacuum Tubes\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eThe AST-EQ50GZMg is a vacuum tube phono equalizer amplifier developed byASTORIt is designed with a circuit configuration using two 12AX7 tubes and one 12AU7 tube, carefully preserving the richness, texture, and delicate musical expression of analog records.\u003c\/p\u003e\n\u003cp\u003eThe amplification circuit uses the company's new typeHigh-Fidelity· Adopts a high-efficiency circuit. By configuring the third stage as a cathode follower, consideration is given to both signal extraction and transmission to subsequent devices. This is a full-fledged phono equalizer that carefully examines the configuration of the amplification stage and output stage using vacuum tubes.\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003eThree-stage configuration using 12AX7 and 12AU7\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eCombines the 12AX7, which has a high amplification factor, with the 12AU7, which has electrical characteristics suitable for the output stage. This configuration is designed to amplify with the 12AX7 and reduce output impedance through the third-stage cathode follower.\u003c\/p\u003e\n\u003cp\u003eThe cathode follower is a circuit method that does not aim for voltage amplification but considers the connection conditions with subsequent devices. This design concept demonstrates a balance between the amplification performance required for a phono equalizer and the stability of signal transmission.\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003eEquipped with two PHONO inputs\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eThe rear panel is equipped with two input terminals, PHONO 1 and PHONO 2. The input selector switch is also located on the rear, allowing connection of two analog players or tonearms and the selection of the input to use.\u003c\/p\u003e\n\u003cp\u003eThere is one output, OUTPUT 1. Without adding complex functions, it integrates the functions necessary for analog playback. It also accommodates systems that use multiple analog sources.\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003eAdopts AST-55PK transformer\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eThe AST-55PK transformer is used. A dedicated transformer is also placed in the power supply section that supports the vacuum tube circuit, emphasizing stable operation.\u003c\/p\u003e\n\u003cp\u003eIn a vacuum tube phono equalizer, it is important not only to handle amplification circuits for tiny signals but also to ensure the stability of the power supply and measures against unwanted noise. This unit, including the circuit configuration and the power supply,ASTORIt is designed with a seemingly solid and reliable construction.\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003e52S aluminum alloy chassis and 5mm thick front panel\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eThe chassis uses 52S aluminum alloy with a thickness of 1.2 mm, and the front panel is made of 5 mm thick aluminum material. Additionally, by using 52S aluminum alloy with a thickness of 1.2 mm for the mid-plate for mounting components, the structure is designed to hold internal components securely.\u003c\/p\u003e\n\u003cp\u003eThe thick front panel and the simple aluminum chassis also give it a calm appearance. Only the power switch is placed on the front, with input switching consolidated on the back. While equipped with the necessary functions, the design is finished in a neat manner with unnecessary decorations minimized.\u003c\/p\u003e\n\u003cp\u003eThe external dimensions are W220 × D350 × H140mm, and the weight is approximately 3.4kg. It is designed in a size that is easy to handle as a standalone phono equalizer, housing three vacuum tubes and a dedicated transformer.\u003c\/p\u003e\n\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0612\/9139\/7377\/files\/side_1d202505-6bee-4da8-b0db-2b0a70adeaef.jpg?v=1793079621\" alt=\"\"\u003e\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003eWideband design from 10Hz to 50kHz\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eThe manufacturer’s published frequency response is 10Hz to 50kHz. It is designed with ample range from low to high frequencies, aiming to naturally reproduce the musical information engraved on analog records.\u003c\/p\u003e\n\u003cp\u003eThis phono equalizer pursues playback that utilizes the rich musical expression of vacuum tubes while preserving the clarity of sound contours and spatial perspective.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"products-desc-title\"\u003eSpec\u003c\/div\u003e\n\u003ctable class=\"table-spec\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003e\u003cspan style=\"font-weight: 400;\"\u003eProduct Model Number\u003c\/span\u003e\u003c\/th\u003e\n\u003ctd\u003eAST-EQ50GZMg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003e\u003cspan style=\"font-weight: 400;\"\u003eType\u003c\/span\u003e\u003c\/th\u003e\n\u003ctd\u003eVacuum Tube Phono Equalizer Amplifier\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003e\u003cspan style=\"font-weight: 400;\"\u003eVacuum Tubes Used\u003c\/span\u003e\u003c\/th\u003e\n\u003ctd\u003e12AX7 ×2, 12AU7 ×1\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003e\u003cspan style=\"font-weight: 400;\"\u003eTransformers Used\u003c\/span\u003e\u003c\/th\u003e\n\u003ctd\u003eAST-55PK\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003e\u003cspan style=\"font-weight: 400;\"\u003ePreamplifier Circuit\u003c\/span\u003e\u003c\/th\u003e\n\u003ctd\u003eNew TypeHigh-Fidelity・High-Efficiency Circuit \/ 3-Stage Cathode Follower Type\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003e\u003cspan style=\"font-weight: 400;\"\u003eFrequency Response\u003c\/span\u003e\u003c\/th\u003e\n\u003ctd\u003e10Hz–50kHz (Manufacturer Published Value)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003e\u003cspan style=\"font-weight: 400;\"\u003eInput Terminals\u003c\/span\u003e\u003c\/th\u003e\n\u003ctd\u003ePHONO1, PHONO2 (RCA \/ 2 Systems)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003e\u003cspan style=\"font-weight: 400;\"\u003eInput Selector\u003c\/span\u003e\u003c\/th\u003e\n\u003ctd\u003eRear Switch\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003e\u003cspan style=\"font-weight: 400;\"\u003eOutput Terminals\u003c\/span\u003e\u003c\/th\u003e\n\u003ctd\u003eOUTPUT1 (RCA \/ 1 System)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003e\u003cspan style=\"font-weight: 400;\"\u003eFront Panel\u003c\/span\u003e\u003c\/th\u003e\n\u003ctd\u003eAluminum Alloy, 5mm Thick\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003e\u003cspan style=\"font-weight: 400;\"\u003eChassis Material\u003c\/span\u003e\u003c\/th\u003e\n\u003ctd\u003e52S Aluminum Alloy, 1.2mm Thick\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003e\u003cspan style=\"font-weight: 400;\"\u003eComponent Mounting Plate\u003c\/span\u003e\u003c\/th\u003e\n\u003ctd\u003e52S Aluminum Alloy, 1.2mm Thick\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003e\u003cspan style=\"font-weight: 400;\"\u003eExternal Dimensions\u003c\/span\u003e\u003c\/th\u003e\n\u003ctd\u003eW220 × D350 × H140mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003e\u003cspan style=\"font-weight: 400;\"\u003eWeight\u003c\/span\u003e\u003c\/th\u003e\n\u003ctd\u003eApprox. 3.4kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003e\u003cspan style=\"font-weight: 400;\"\u003ePower Supply\u003c\/span\u003e\u003c\/th\u003e\n\u003ctd\u003eAC100V\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003e\u003cspan style=\"font-weight: 400;\"\u003eWarranty\u003c\/span\u003e\u003c\/th\u003e\n\u003ctd\u003eNo manufacturer warranty \u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cdiv class=\"products-desc-title\"\u003eReview\u003c\/div\u003e\n\u003cdiv style=\"text-align: start;\"\u003e\n\u003ch3\u003e\u003cstrong\u003eSound quality tendencies from the design perspective\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eThe AST-EQ50GZMg is a tube phono equalizer featuring an amplification circuit using 12AX7 and a cathode follower configuration using 12AU7. While you can expect the thick and smooth sound characteristic of tubes, the third-stage cathode follower makes it a configuration that also considers the load conditions on the output side.\u003c\/p\u003e\n\u003cp\u003eThe 12AX7 has a high amplification factor and is a vacuum tube suitable for amplifying the small signals required in a phono equalizer. When combined with the 12AU7, it can be expected to deliver playback that emphasizes midrange density, the realism of the sound image, and natural reverberation.\u003c\/p\u003e\n\u003cp\u003eIn addition, the front panel uses 5mm-thick aluminum alloy, and the interior is equipped with an independent component mounting mid-plate, showing attention to the structure of the chassis. Despite its simple appearance, the layout carefully organizes the amplifier circuit, power supply, and chassis elements.\u003c\/p\u003e\n\u003cp\u003eEquipped with two PHONO inputs, it is also suitable for analog systems that switch between multiple players and tonearms. This is aimed at those who prioritize the combination of circuit design and vacuum tubes.ASTORThis is a phono equalizer.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"ASTOR\/アストロ電子企画","offers":[{"title":"Default Title","offer_id":50964646789377,"sku":"EQ50GZMg","price":118800.0,"currency_code":"JPY","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0612\/9139\/7377\/files\/front_2e68fb08-7760-42a2-b0a3-05ee7f27fb2f.jpg?v=1793079621","url":"https:\/\/exclusive-audio.jp\/en\/products\/astro-electronic-planning-ast-2000mvipsp-mono-preamp-5","provider":"ExAUDIO","version":"1.0","type":"link"}