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JJ ELECTRONICS

KT77 EL34 JJ Electronics Matched Pair – AMPLITREX Tested – New Production – Original Box

KT77 EL34 JJ Electronics Matched Pair – AMPLITREX Tested – New Production – Original Box

$123.00 CAD
$123.00 CAD
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KT77 EL34 JJ Electronics Matched Pair – AMPLITREX Tested – New Production – Original Box

MADE IN SLOVAKIA

General Description

The KT77 is an octal-based beam power pentode , suitable for use in the vast majority of amplifiers designed for the EL34 . Compared to the EL34 and E34L, it offers more available power, more authoritative bass and greater headroom , while maintaining a high level of detail and balanced tonal reproduction.

The KT77 JJ represents one of the most successful modern interpretations of this historic valve: a production designed to guarantee reliability, electrical coherence and high-level sonic performance .

The tubes are NEW , supplied in the original JJ box , and carefully selected and matched in our laboratory using AMPLITREX , to ensure stable, uniform and repeatable operation within the amplifier.

A highly popular choice as an advanced alternative to the EL34 , the KT77 JJ retains its underlying musicality while adding control, extension and authority .

Sound Characteristics

The KT77 JJ's tone is modern, balanced and solid, with a coherent response across the entire audio spectrum.

Bass: Deep, controlled, and well-articulated. The low end is tight and fast, with a more substantial feel than a traditional EL34, making it ideal even for amplifiers with large transformers.

Mids: Rich, present, and well-structured. Vocals sound natural and well-defined, with excellent intelligibility and no excessive coloration.

Highs: Open, tidy, and well-extended. The highs are clean and detailed, never aggressive, and are suitable even for high-resolution systems.

Dynamics: Responsive and controlled. The KT77 JJ responds promptly to transients and conveys a sense of controlled power, making it versatile and musical across a wide variety of genres.

Soundstage: Wide and stable soundstage, with good depth and proper instrument separation. The imaging is focused and believable.

🎧 Use in Hi-Fi Amplifiers

Ideal for compatible EL34 / KT77 amplifiers, both in push-pull and single-ended configurations where applicable. An excellent choice for those seeking greater control and definition , without sacrificing musicality.

🎸 Use in Music Applications

They are also highly appreciated in the guitar amp field, where they offer a firmer and more defined sound than the EL34, with superior headroom and a more compact and controlled low frequency response.

🎯 Note for audiophiles and technicians

  • brand new ,
  • tested and matched on AMPLITREX ,
  • supplied in original packaging ,
  • designed for those who want modern reliability and a solid, balanced and authoritative sound output .

An ideal pair for upgrading or maintaining EL34-compatible amplifiers at their peak performance, with the security of a professional selection from Vacuum Tubes Treasures .

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 musical instruments
• Output: Excellent – ​​strong and stable output
• Short circuits and GAS: absent

The pair is matched exclusively on real static parameters, to ensure consistency, reliability and symmetry between the two channels.

Conditions

• Supplied in original box
• Functionality: impeccable
• Factory new valves, tested and in perfect working order

Warranty:
• Consumers: 24 months (Legislative Decree 206/2005)
• B2B: articles 1490 et seq. of the Civil Code apply

Additional Information

JJ tubes may exhibit slight differences in glass bulb height, with no impact on technical or sonic performance.

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

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.