Weird noise. Sounds like a pocket full of change.

[jmaf]

MESA EL34 STR 442

They were in it when i got it, supposedly new:

EL34 STR-442 Russia - Svetlana
An incredibly warm and rich sounding EL-34 that is reminiscent of the US 6CA7 - Thick rich low end that is still defined and light, with a Euro-voiced mid range edge and sparkling highs that are incredibly smooth and musical - Its tonal character falls between and EL-34 and a 6L6, striking a perfect balance of the best attributes from both - Excellent build quality provides exceptional consistency and reliability - Capable of handling higher voltage requirements

I've had issues with "new Svetlana's" from Reflektor in the past. One pair of 6L6SV's (SV are their GC IIRC) started arc'ing with 2 or 3 hours of use....