memento

audio&visual, headphone&earphone, bicycle, music, animation, book, wine...趣味領域の外部記憶装置です。 <since 10 aug 2006>

Mullard ECC83

eBayで購入したMullard ECC83が到着。木曜日に不在配達通知が入っていたので、実質10日ほどで英国から到着したことになります。


思っていたよりもちゃんと梱包されていました。


中の緩衝材は過剰なくらい。


1本はほぼ新品同様で、もう1本は8割のライフタイム。双極特性および2本のマッチングはばっちりです。


2 MATCHED MULLARD ECC83 12AX7 MADE MARCH 1962 TESTED

Codes: Valve 1: I61B2C2; Valve 2: I61B2C3;

Both made at Mullard's Blackburn factory, England, UK. in 2nd and 3rd weeks of March, 1962. Just pre-dating Mullard's yellow-print period.


Copper posts.
Large halo getters.
Seamed envelope construction.
13mm plates.
Old shield logo.
Good print.


The I61 was the first design of ecc83 to follow Mullard's long plates.
These early short-plate-design ecc83's feature juicy-sounding copper posts, which were phased out by the mid-1960's.


Tested good for shorts; continuity; microphony; and emissions.
No hiss, no hum, no noise, no microphonics. Guaranteed.


Emissions test circa 100% compared to nos valves at specified test voltage of 12.6v.

Life test: 100% and 80% respectively. Valves are lightly used.


Test results: Valve 1: triode 1: 69; triode 2: 69;
Test results: Valve 2: triode 1: 67; triode 2: 68;

NOS (unused) vintage Mullard ECC83's typically score around 68 per triode on the tester used. (Below 41 is 'bad').
NB: Valves tested at specified voltage of 12.6v. Tester does not test transconductance.


12AT7もMullard ECC81に交換。All Vintage Mullard にして現在バーンイン中。
今日の夜に軽く音出ししてみます♪