Tung-sol RI 6550 how much can it take?

[Steve Conner]

Hi guys

I recently started collecting parts for a high powered tube bass amp. I have the output and interstage transformers from a Fender 300PS, and the power transformer from a large tube ham radio transmitter, which gives a choice of 320V, 550V or 820V B+, and 6.3V at 12A.

I was thinking of hooking this lot up to a sextet or even an 8 pack of the new "Tung-Sol" reissue coke bottle 6550s. I tried a pair in a lower powered amp and loved the look and sound of them. But the other day I heard rumours that these tubes are not to be trusted over 550V. Can anyone comment on this?

Also, any alternative suggestions that would give good bang for the buck? I was thinking of a 12-pack of those Sovtek "5881"s. I remember someone testing these to destruction a while back, and I bet they could take 800V B+.

[Satamax]

Hi Steve, the tungsol reisues, huh, i don't know realy, but they are suposed to cope with high B+ tho, i don't if they've been specked properly! Svets would hold i'd think, or KT88.

For the 5881 from sovtek, that's the wafer base ones sold either under sovtek 5881 or Radio 6P3S-E

http://cgi.ebay.fr/4-x-6P3S-E-Roehre...QQcmdZViewItem Actualy GT tubes are the ones with normal base i think and many others! Biassed some of thoses at 32W at iddle with no prob whatsoever for more a year!

What you're talking about ampwise is the baga from Ken Gilbert