Vintage 6386 Dual Triode Vacuum Tube | Characterized & Selected for Vari-Mu Applications

For sale is a genuine vintage 6386 SYLVANIA Black Plate dual-triode vacuum tube selected from a larger characterized inventory.

This tube has been individually inspected, tested, characterized, and ranked as part of an inventory of 37 tested 6386 tubes. Rather than relying on brand, plate construction, stated condition, or a single tester reading alone, each tube was evaluated according to measured performance.

Individual selection is based on three primary characteristics:

• Transconductance strength
• Triode balance
• Vari-mu tracking behaviour across multiple operating points

This particular tube Ranked #5 out of the 37 tested tubes.

Each tube is assigned a Selection Grade based on these measured characteristics. Please refer to the included Tube Characterization Report for the specific measurements, curves, ratings, inventory ranking, and Selection Grade of the tube offered in this listing.

The goal of this process is not simply to identify tubes that "test good," but to provide meaningful characterization data that allows a buyer to evaluate the individual tube according to the requirements of their particular application.

Documentation Included

Please review all photographs and supporting documentation carefully, as they form an important part of this listing.

The listing includes:

• Photos of the actual tube being sold
• Photos of the original box, when applicable
• Individual Tube Characterization Report
• Full measured transconductance curves
• Strength, triode balance, and tracking data
• Selection Grade and inventory ranking
• Photos from the original inventory acquisition
• Photos of the test equipment used
• Supporting test methodology and inventory provenance information

Inventory Provenance

This tube originates from a larger inventory acquired from a well-known broadcast company and was part of a professionally maintained stock of vintage vacuum tubes. The inventory included numerous tubes still stored in their original individual boxes and original manufacturer sleeves.

Photos of the acquired inventory and surviving original packaging are included with the listing to provide additional context and provenance.

Detailed Characterization

Unlike a traditional vintage-tube listing that may provide only a single tester reading or a simple "tests good" statement, this tube is supplied with detailed multi-point characterization data.

The included documentation allows the buyer to review the measured performance directly rather than relying solely on descriptive claims.

Please refer carefully to the photographs and attached Tube Characterization Report for the complete test results, transconductance curves, strength information, triode balance, tracking performance, Selection Grade, and inventory ranking for this specific tube.

Sold as vintage electronic equipment. Test results were obtained using calibrated equipment under documented conditions and are provided as a reference. As with all vintage tubes, no guarantee is made regarding performance in any specific circuit or application.

Characterized and documented by Black Mountain Amplifiers Inc.
Offered for sale exclusively through Pizzolato Amplifiers
Kelowna, British Columbia, Canada