1x VintageNOS SealedBox Matsu/Mullard 6X4 Rectifier Tube /1960s Panasonic /Unopened Classic /Museum Grade /EZ90 CV493 U78 CV4005

our entire catalog is now available w/ digital test results! including gain noise waveform checks and more

sealed box factory fresh 1960s panasonic are hard to find, museum grade unopened classics, + will only go up in value

crown jewel panasonic! highly revered musical sound reproduction, + top customer-ranked mullard / telefunken alternative

described as a rich full tonality w/ plenty of detail, sweet warm balance, dimensional presence, all w/ translucent airy highs

this elegant musicality is expressive, clean, low noise, all w/ excellent stage dynamics (+ rich overdrive in guitar amps)

this quite versatile cult classic, reproduces a smooth extended sound profile, reveals lush mids, + has a defined low-end

back then, mullards vacuum tube empire was vast, setting up advanced manufacturing facilities worldwide, along w/ philips

this famous transfer of technology provided legendary old school metallurgy, engineering, quality, longetivity, + low noise

this same british cathode-process, chemistry, anode plates/supports/electrode geometry +glass, resulted in coveted playback

transform your playback! tune up your fidelity w/ detailing, articulation, warmth, and more sound system definition

old school vintage rectifier tubes are a great way to affect headroom and power, based on the voltage supplied

the 6x4 has a history going back to the 1940s, and replaces the EZ90 6z31 cv493 u78 v2m70 u707

w/ premium versions = 6063 6x4w and cv4005, and different max-rating versions: 6202 6BX4 and 6X4WA

these will be similar (w/ different connections so re-wire or adapter) to 6z4 chinese and 6Ц4П russian variety

+ similar to the different-base classics (rewire / adapter): 6x5 6x5gt ez40a or the cv572 ez35 / 5993 we351a 5852

6X4/w EZ90 U78 V2M70 U707 6AV4 WTT100 CV493 6063 6X4W CV4005 QA2407 6Z31 6202 6BX4 6X4WA 

6C4P-EP      6X4

pin 1   a1           a1

pin 2   nc           nc

pin 3   f            f

pin 4   f            f

pin 5   k            nc

pin 6   nc           a2

pin 7   a2           k

if ever opened, give several sessions (150+ hours) w/ your amps specific voltage to fully break-in, before testing

ships well packed worldwide! economy/express/priority postage available