Favorite 300B: Sophia vs KR

Simmon solid state sounds better to you then something is wrong. I never had that magic with solid state.

Thanks to all of you for your participation in this valuable thread. I am enjoying all of the comments and posted some earlier and will only say the Takasuki's are still my favorite with my amp. thus this comment is a bit off course and adds nothing to the fact of any further sound re-inforcement of these tubes.

Since we are all talking so much about the high cost of these tubes (along with the great sound) I will share with
you that my amp. designer (Gary Dews from England) gave me a hint that in his experience (and some of his long-time customers) he has noted an "increased" life to any 300b tube if you have an adequate way to cool them......obviously this makes total sense.

He suggested I pick up a low voltage/low noise fan that is capable of moving some air from the back of the amplifier and blow onto the tubes. I thus have purchased a small computer tower type fan (4 X 4 X 1 inch) that is rated at very low noise and plan on configuring it (in an easily removeable way) on the back base of my amplifier to blow air across the tubes when in use to move air. My little fan is rated at 33DB noise and 56CFM so we will see. I also picked up a 72 inch power cord that has an variable speed control for the fan.

Everything I have read states you have to be 3-4 feet anyway to even hear it running so we will see. The key hear is to get one that moves some air yet is rated very low noise and they are out there and mine will be adjustable.

No offense but I paid $20 bucks for this experiment and what could it possibly hurt? The little fan is supposed to be here soon and if nothing else it will ease my guilt of trying to extend the life of the 300B tube which is a topic in itself.

Some of you might think I am lost in the wilderness but maybe some of you have already experimented and it would be nice to know if so.

Gwalt,
Your plan makes sense to me. The builder of my amp designed the circuit to be as he says "very easy" on the 300b tubes to greatly extend their lifespan. He alo used large over-speced transformers. Even when the amps are on 12-16 hours the transformers are warm but never hot to touch at all.
I hope the fans work out for you.

Jwm was you post aimed at mine? I never mentioned solid state? My equipment is all tube based.

Charles1dad:

Thanks for the reply. I forgot to mention I have no real detection of running the tubes hard in the circuit as I think both of our amps. qualify as over built.

My transformers do not even get warm to the touch after 12 hours but the base of the tubes are warm and I think the theory is if you keep the tubes cooler you tend to re-tard the damages that internal heat can do.

I run the tubes @ .68ma which is considered approximately 65%-70% of full output.