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JJ ELECTRONICS

6550 JJ Matched Quad - AMPLITREX Tested Tubes - NEW - 4 Valves IN ORIGINAL BOX

6550 JJ Matched Quad - AMPLITREX Tested Tubes - NEW - 4 Valves IN ORIGINAL BOX

€229,00 EUR
€0,00 EUR €229,00 EUR
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6550 JJ Matched Quad AMPLITREX Tested Tubes (4 Valves) NEW - IN ORIGINAL BOX

MADE IN SLOVAK REPUBLIC

The 6550 JJ represents one of the most appreciated modern power tubes for balance, reliability and dynamic handling.
Designed to deliver consistent performance and full, musical sound, they are individually tested in our lab with Amplitrex AT-1000 at real operating voltages, to ensure accurate static matching on anode current (Ia) and transconductance (Gm).
Each quartet is selected and electrically verified to offer stability, symmetry and long operating life.

Selection Process – Technical Check and Sound Consistency

  • Testing the Amplitrex AT-1000 at real-world operating voltages
  • Static matching on main parameters (Ia / Gm)
  • Measurements taken after 10 minutes of preheating
  • Microphony, emission and isolation control
  • Packaged in original box, sealed to ensure authenticity

Sound characteristics

  • Bass: solid and tight, with excellent control and articulation. Precise rhythmic foundation, never intrusive.
  • Mids: natural and transparent, with balanced timbre and realism in the voices.
  • Highs: extended and clean, with harmoniously integrated brilliance and no harshness.
  • Dynamics: prompt and stable, with fluid response and control even at high volumes.
  • Soundstage: wide and coherent, with good depth and centered soundstage.

🎧 Ideal for medium and high-end Hi-Fi systems, where balance and musicality are sought.

🎸 Excellent for musical amplifiers requiring power, headroom and progressive dynamic response.

Test Specifications

  • Valves tested on Amplitrex AT-1000 Tube Tester
  • Measurements taken after 10 minutes of preheating

Additional Tests Performed:

  • Microphonics: Standard – compliant for use in hi-fi and music amplifiers.
  • Output quality: excellent – ​​strong, stable and smooth output.
  • Short circuits and GAS: absent.

Our 6550 JJ valves are tested and matched to real static parameters, ensuring consistency and reliability over time.

Conditions
Supplied in our original box.
Functionality: impeccable.
Factory new valves, tested and in perfect working order.
24-month legal guarantee (consumers, Legislative Decree 206/2005). B2B: Articles 1490 et seq. of the Italian Civil Code apply.
Returns for sound preferences/tube rolling are not accepted. 14-day returns only with intact seal and unused tube.
The warranty covers only original defects in conformity; wear and tear, improper use, and tampering are excluded.

Additional Information
JJ tubes may exhibit slight variations in glass bulb height, with no impact on performance.

FAQ - Frequently Asked Questions:

  • Request: After installation, do they sound loud right away? Or do they need to be broken in?
  • Answer: They sound good right out of the box, but they get better with time. After just 50 hours, the bass becomes tight, and around 100 hours, the tonal balance stabilizes. Breaking in is part of the process that makes the sound more natural and engaging.

🔍 Find out what we really think: read our complete guide to the 6550 JJ.

Terms of Sale & Safety

Sales Terms & Product Safety

Each vacuum tube is carefully selected, tested, and verified in our laboratory before shipment. Where stated in the listing, test results, matching data, and declared characteristics refer to measurements performed using the specified test equipment and operating conditions.

Sound descriptions are provided for guidance only and reflect the characteristics generally associated with that particular tube type. Personal sound preferences, tube rolling, or perceived differences between audio systems do not constitute a product defect.

Before installation, please verify the tube’s electrical and mechanical compatibility with your equipment and follow the manufacturer’s instructions.

New production and NOS tubes are shipped with a tamper-evident security seal and internal technical documentation to ensure traceability of the product’s condition at the time of shipment.

Product Safety (GPSR)

Vacuum tubes are electronic components intended exclusively for use in compatible equipment and must be installed in accordance with the equipment manufacturer’s instructions.

Due to their historical or vintage nature, certain technical specifications may be based on original datasheets or equivalent technical documentation when documentation from the specific manufacturer is unavailable.

Use only with suitable equipment. Keep out of reach of children.

Shipping & Returns

Shipping & Returns

We ship worldwide using carefully selected express carriers and protective packaging specifically designed for vacuum tubes.

If you change your mind, you may exercise your right of withdrawal within 14 days of delivery, where applicable under the relevant consumer protection laws. The product must be returned complete with its original packaging and accessories, in the same commercial condition in which it was received. Return shipping costs are the responsibility of the customer.

Every returned item undergoes a technical inspection. Installation, use, tube rolling, or any other handling may reduce the product’s commercial value and may affect the refund amount, in accordance with applicable law.

If you believe the product has a lack of conformity, our laboratory will carry out the necessary inspections and apply the remedies provided by the applicable consumer protection legislation.

For further details, Customers are invited to consult the “Terms and Conditions” and “Refund Policy” sections of our website, or to contact us before placing an order.

Vacuum Tubes Treasures
www.vtt.store | www.vacuumtubestreasures.com
📧 info@vacuumtubestreasures.com

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  • ATTENTION PLEASE

    Please understand that the writing on the glass of vintage valves has become very delicate over the years and comes off easily. You must handle them with extreme care to avoid this. Wear and damage to the writing on the valves reduces their market value and causes damage. Please exercise extreme caution.

  • ATTENTION PLEASE

    We wish to inform you that any attempts to manipulate shipping destination information in order to obtain lower shipping rates may be considered fraudulent acts. Please provide accurate information and contact us if you have any concerns. We reserve the right to review and, if necessary, cancel orders that we deem to be in violation of our conditions. Thank you for your understanding and cooperation.