Basic EL34 and 6sn7 tube recommendation.


I have a Mystere IA-11 tube integrated amp from sister company PrimaLuna. I bought it preowned and like-new 1.3 yrs ago and enjoy it immensely. It is outfitted with Electro Harmonix EL34 and 6sn7 tubes. (Upscale Audio is the US distributor of Mystere and PrimaLuna and also an EH supplier.)

Everything is fine currently, so I enquiring if I should replace with the same EH tubes when it's time, or should I use another moderately priced brand. I have no inclination to compare and roll tubes looking for the best match. Just looking for a good solid recommendation to plug and play.

On another related issue, my amp has Primaluna's auto-bias circuitry that automatically adjusts the tube bias, so how will I know when tubes are at the point of needing replacement, unless they are burned out completely. Thanks.
128x128mjcmt

Showing 1 response by edcyn

I've been enjoying the 6550's that Upscale recently sent my way. Midrange isn't quite as beautiful as my EL34 tubes delivered but the 6550 midrange is still beautiful as hell and the 6550's give me more top, bottom and punch. (I can't remember the brand name and I ain't gonna pull one of the tubes out its socket to see if it has a maker's mark.)