1966–67 M.B.L.E. Brussels EF86 / 6267 Exact Matched Pair – Mullard + Tungsram – Triplett Tested

Two respected European labels. One M.B.L.E. Brussels production family. One exact measured match.

Offered here is a carefully selected pair of vintage EF86 / 6267 audio pentodes manufactured by M.B.L.E. in Brussels, Belgium.

Although the commercial labels differ, the etched Philips-family factory codes and closely matching internal construction identify both tubes as Brussels production. Their measured performance is identical.

Tube 1 — Mullard-branded

• Type/construction code: 8Y5
• Factory/date code: L7F1
• M.B.L.E., Brussels
• June 1967, first production week
• Triplett 3444: 2,200 µmhos
• Plate current: 2.8 mA

Tube 2 — Tungsram-branded

• Type/construction code: 8Y5
• Factory/date code: L6F5
• M.B.L.E., Brussels
• June 1966, fifth production week
• Triplett 3444: 2,200 µmhos
• Plate current: 2.8 mA

Exact measured match

Both tubes produced the same transconductance and plate-current readings on the Triplett 3444.

• No shorts detected
• No abnormal leakage detected
• No noise detected during testing
• No microphonics detected during testing

The pair shares the fine diamond-mesh screens, dark upper cuffs, top halo getters, broad silver flashing, and closely corresponding internal structure associated with this Brussels production family.

The Mullard printing remains attractive and clearly visible. The Tungsram commercial stencil shows natural vintage wear, while its important etched factory and production codes remain clear. Both tubes present well and have healthy, intact internal assemblies.

Philips-family Brussels EF86 tubes are often appreciated by enthusiasts for a clear, detailed, responsive presentation with a natural sense of warmth and balance. Individual results will depend on the circuit and associated equipment.

Suitable for equipment specifically designed for EF86, 6267, or Z729 tubes. Please confirm the required tube type in your equipment manual.

Both tubes are supplied in new white replacement boxes marked Tube 1 and Tube 2.

The exact tubes pictured are the tubes the buyer will receive.

Test results reflect measured performance at the time of testing.

Professionally packed by VTubeAudio.

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