[Stereo58]

Hi,

I have the Ultra EC preamplifier with the phono section that I purchased back in July 2006. Believe it or not it still has the original preamp tubes in it and still sounds pretty damn good!

However, I’m thinking of retubing it and will probably sound even better even in the phono section! I have actually never taken the cover off and I would like to know what brand tubes were installed at that time?

I know there’s two line/control stage tubes that need high gain that are the 12AT7A in the phono section has the 12AX7A

Also, my on/off switch light flickers a little bit and it’s very intermittent when it does that and then the red indicator light next to the  on/off switch doesn’t even light up! I suppose it’s a bulb that needs replacing behind those?

[FullRangeMan]

Welcome to AC 

[Phil A]

Welcome!

[ArthurDent]

Greetings & Welcome to AC     Likely you'll find the pre tubes are Sovtek 6N1Ps, which were Frank's standard OEM at the time. The recommended upgrade from those is the 6922 line of tubes. Recently replaced those my self in both my Ultra EC preamp and Ultra DAC. Frank's current stock 6922 is the E-H at $32 each. Lots of options both new & NOS available.

Yes, the flickering light switch is not that unusual over time. To my knowledge doesn't have any effect on the sound. Had the same issue with my T-8 pre, Frank replaced the switch when I upgraded that chassis to the CF line. As to the indicator light next to the switch, you might ask Frank about that. I don't think mine has ever lit up. It may have been a holdover from before he used lighted switches, and would have had a bulb behind it. Happy listening.