Special Quality 10,000+ hour 12AU7. Arguably the best 12AU7 ever made; very low noise and superb inner resolution; incredible high-end extension and very smooth, this is the Holy Grail of 12AU7's (the best sounding 12AU7 are ECC802S Telefunken, 7316 Amperex Holland, 12AU7 Telefunken, 12AU7 Mullard Long Plates, 12AU7 Holland Long Plates 1950's, Mullard CV4003, 12AU7 RCA clear top) - Wavac prt1 preamp (pr-t1) - Audio Note M1 preamp - Octave (Germany) - VTL TL 7.5 MKII preamp - VTL 6.5 - Audio Note M8 - Mastersound PH-1 - Airtight TC3 TO BUY ECC802S TELEFUNKEN

SONIC COMMENTS: ---------------------- "I put the Telefunken CCA tubes in the inner line-stage of the Njoe Tjoeb replacing Philips JAN 6922. In the Prima Luna Two I replaced the 12AU7 with ECC802S Telefunken and the JAN 12AX7 Electro-Harmonix with 12AX7 Telefunken smooth plates. The difference is immediate (HP : Quad 57 and REL Q-100) : perfect timbral differenciation, neutrality and equilibre in the all frequence range (with very close souding instrument in a chorus, by exemple) spatialization very precise and aerial. Bass are also short, dry and sculpted, not just physical impact. You can listen perfectly , also in studio recording like Miles Davis quintet for Atlantic, the position of each membres of the formation. Or the Mingus' fingers on the chord. In fact, you forgot the material : it's just music. It's maybe a lot of money, but it's also a lot of pleasure!" Hi Brendan, The pairs of NOS Telefunkens ECC802S and EF806S arrived safely. Swapping out the stock tubes in my Eastern Electric M520 produced the most astounding musical change I have heard in any of my stereo systems that I have ever heard - bar none. And I have tried all the upgrades available - cables, interconnects, power cords, conditioners, etc. in various system setups. I still can't believe it but swapping the stock tubes back in reveals it to be a real and consistent improvement that everyone I've invited over can hear. While expensive, these tubes are the best upgrade investment I've made. I find myself listening to this second system more over the last few days than my much more expensive main system. Thanks for great advice and great products!