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MAGNAVOX

6550 MAGNAVOX by TUNG-SOL Type 2 – 4th Generation - AMPLITREX Matched Quad - Made in USA

6550 MAGNAVOX by TUNG-SOL Type 2 – 4th Generation - AMPLITREX Matched Quad - Made in USA

4.505,00 PLN
0,00 PLN 4.505,00 PLN
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6550 MAGNAVOX by TUNG-SOL Type 2 - 4th Generation Gray Plates Triple Halo Getter Three Holes Matched Quad Tubes MADE IN USA

Description:

This matched quartet of 6550 MAGNAVOX by Tung-Sol , Made in USA, belongs to the Type 2 – 4th generation , one of the most mature and musically balanced versions of the historic American 6550.
The construction with gray plates , triple halo getter and three ventilation holes reflects a production phase oriented towards maximum electrical stability, controlled thermal dissipation and long operational reliability, maintaining intact the authoritative sound character typical of the best vintage 6550s.

The set was selected as Matched Quad and tested with professional equipment, it features the same manufacturing code on the entire quartet with homogeneous behavior and consistent response on all tubes.
This is a quartet designed for medium-high and high-end amplifiers, where balance, control and tonal solidity are fundamental requirements.

Sound Character

Bass
Deep, compact, and perfectly controlled. The low end is authoritative but never intrusive, with excellent articulation and the ability to sustain complex loads without losing definition.

Medium
Balanced, full, and natural. The vocals are solid and well-focused, with a rich yet composed harmonic texture. They perform excellently on jazz, classic rock, and orchestral repertoire.

High
Clean, extended, and uncluttered. The highs are present but never aggressive, with a balance that favors prolonged listening and delivers air and detail without fatiguing.

Dynamics
Convincing and stable. Transient response is prompt yet controlled, with a sense of always-available power reserves.

Soundstage
Wide and well-structured, with a solid and credible soundstage. Excellent separation of levels and stable imaging even at high volumes.

🎧 Use in Hi-Fi Amplifiers

Ideal for:

  • 6550 push-pull amplifiers
  • final and integrated courses in American schools
  • systems that require balance, control and reliability over time

An excellent choice for those who want the classic 6550 sound in a more modern and balanced version than the very first generations.

🎸 Use in Music Applications

Appreciated for:

  • high-powered bass and guitar amplifiers
  • professional applications where stability, headroom and predictable response are required

They offer a solid, defined and resistant sound even under demanding conditions of use.

🎯 Note for audiophiles and technicians

This Matched Quad of 6550 MAGNAVOX by Tung-Sol Type 2 – 4th Generation represents:

  • one of the most reliable and musically balanced versions of the 6550 USA
  • Robust construction with triple halo getters and gray plates
  • accurate matched selection
  • same manufacturing code
  • excellent compromise between sound performance, durability and collectible value

An ideal quartet for those looking for real performance, tonal coherence and the authentic character of the great American 6550s , without unnecessary compromises.

Test Results:

Tested on AMPLITREX AT-1000 Tube tester:
Test Conditions: Va = 450V ; Vg2 = 300V ; Vg = -30V
Measurements are taken after 10 minutes of preheating the tubes.
Average 100%: Gm = 6.50 ; Ia = 50 mA
TEST RESULT: All valves fall at least in the STRONG range, with two elements in the VERY STRONG area

Valve 1: Gm = 5.95 ; Ia = 48 mA
Valve 2: Gm = 5.91 ; Ia = 50 mA
Valve 3: Gm = 5.15 ; Ia = 44 mA
Valve 4: Gm = 5.32 ; Ia = 40 mA

Additional Tests Performed:

  • Microphonics: Standard. Tested and approved for use in hi-fi and guitar amplifiers.
  • Output Quality: Excellent – Very strong and stable output, no fluctuations.
  • Short circuits and GAS: Absent.

Conditions:

  • Condition: Vintage tubes - Tested and in perfect working order. Shipped in our custom box for optimal protection.
  • Functionality: Fully functional.
  • Cosmetic condition: Good – Lettering partially eroded, but still legible. Valve body in good condition. See photos for details.
  • Manufacturing Code: 3227350 → 322 indicates the manufacturer, i.e. Tung-Sol Electric Inc., Newark 4, NJ - 73 → 1973 - 50 → 50th week of the year

Find out why our valves are different →

Condizioni di vendita e sicurezza

Anti-Tamper Security Seal Policy:
Each product is sealed to guarantee quality and integrity.
The right of withdrawal is subject to the seal remaining intact, as provided for by the Consumer Code.

Eco-Friendly Packaging:
The tube will be shipped with protective packaging to ensure safety during transport.
We use recycled and recyclable paper for packaging, along with brown ECO-KRAFT adhesive tape, eco-friendly and solvent-free.

Important Notes:
This tube, manufactured according to the standards of its era, is designed to operate in equipment compatible with vintage tubes.
It is recommended to follow standard safety guidelines to avoid malfunctions or damage.

Safety Assurance:
Although not tested according to modern GPSR regulations, this tube was designed to operate safely under the conditions for which it was manufactured.
We recommend using it only with equipment that supports vintage tubes, in order to avoid risks of malfunction or damage.
Technical data note:
In some cases, the technical data provided may be based on datasheets from other manufacturers or on equivalent historical specifications, when a specific official datasheet for the production batch of the listed item is not available.
Electrical characteristics may vary slightly depending on the production batch and manufacturing period, as is typical for thermionic components.

Safety Information:
Warning: Keep out of reach of children.
To be used under adult supervision.
Use the product only with equipment designed for vintage tubes.

Shipping & Returns

Shipping & Returns

Shipping Costs

Shipping costs vary depending on the total amount of the items in the cart and are calculated automatically during the checkout process.
All shipments are fully insured. The courier is automatically selected based on destination, weight, and shipment characteristics.

Shipping Times and Delivery

The indicated delivery times are purely indicative.
Any delays, storage issues, or operational changes made by the carrier (for example during peak periods such as holidays) are not attributable to Vacuum Tubes Treasures.

In such cases, we will nevertheless provide the Customer with all necessary support to open claims or assistance requests with the appointed courier.

International Shipping (Non-EU Countries)

For orders shipped to countries outside the European Union, any customs duties, import taxes, or additional charges are the sole responsibility of the recipient.
Vacuum Tubes Treasures has no control over these costs, which may vary from country to country. Customers are therefore advised to contact their local customs authorities prior to placing an order.

Warranty

All products sold by Vacuum Tubes Treasures are covered by the legal warranty of conformity, in accordance with Italian Legislative Decree No. 206/2005 (Consumer Code) and the Italian Civil Code (Articles 1490 et seq.), under the conditions set out below.

Warranty for Vacuum Tubes

Vacuum tubes, being components subject to wear and of vintage or specialized nature, are covered by a specific warranty of 6 (six) months from the date of delivery.
The warranty covers exclusively proven manufacturing or conformity defects that arise during proper use in accordance with technical specifications.

The warranty does not cover:

  • normal wear and tear,
  • subjective sound preferences,
  • use in incompatible equipment,
  • tampering or improper use.

Right of Withdrawal

Purchases made on the Vacuum Tubes Treasures website are governed by Italian regulations on distance contracts (Legislative Decree No. 206/2005).

Consumers have the right to withdraw from the contract within 14 (fourteen) days from the date of receipt of the goods, without providing any reason.

Conditions for Exercising the Right of Withdrawal

The right of withdrawal may be exercised only if:

  • the product has not been used,
  • the product is returned in its original condition,
  • the tamper-evident security seal is intact and not broken.

📌 Returns are not accepted for reasons related to sound preference, tube rolling, or subjective audio evaluation.
As with a music recording, a vacuum tube cannot be returned simply because its sound does not match personal taste.

Effects of Withdrawal

In the event of a valid withdrawal:

  • all payments received, including standard shipping costs, will be refunded,
  • refunds will be issued within 14 days from receipt of the returned goods,
  • the refund may be withheld until the goods have been received and inspected.

Refunds will be made using the same payment method used for the original transaction, unless otherwise agreed.

Return Shipping Costs

Return shipping costs are borne by the Customer, except in cases of:

  • verified defective products,
  • errors attributable to Vacuum Tubes Treasures.

In such cases, return shipping costs will be fully covered by us.

Damaged or Incorrect Items

If the Customer receives a damaged or incorrect item, it must be reported within 5 (five) working days from delivery, by email or telephone, clearly stating the issue.

Uncollected Parcels, Storage, and International Shipments

It is the Customer’s responsibility to monitor the shipment and promptly arrange for collection or customs clearance.
Any costs, delays, or losses resulting from:

  • failure to collect the parcel,
  • prolonged storage,
  • abandonment of the parcel at customs,

do not entitle the Customer to any refund.

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.