New KT150 tubes?

04-20-14: Wolf_garcia
BASE NOTES...man..."Base fishing anyone?"

LMAO, Base fishing? No, not quite. I do however find 'Angling' for the Lesser Pedantic Grammar Pilchard considerably more edifying, Altho, a somewhat 'predictable' feeding habit does tend to leave them incapable of resisting the bait/bate as proffered.

;0}

I'm a bass player who doesn't fish.

Wolf ... I checked eBay. Right you are. Number of vendors offering to sell KT-150s for prices you mentioned above. Even still, I have three concerns.

First is that ARC hasn't approved the tube for use in its amps yet. I suspect that the additional current draw is not signficant, but I don't want to experiment with my amp.

Second, my amp requires matched tube sets. I've had some difficulty in sourcing pairs that match well. So far, only ARC has been able to provide reliable matched sets.

Third, I do not know anything about the reliability of the eBay vendors. At least with vendors ARC and Upscale Audio, I am comfortable that the tubes are properly run in and tested before being sold.

In short, it might cost me $700+ to buy 2 quads just to satisfy my curiosity .. although I am curious about the tubes.

I'm confused...Only ARC has matched sets? Have other matched sets proved unreliable? I don't understand what that means since you say they haven't approved them for use, but then I'm easily confused. Many Ebay sellers know what they're doing and are rated by the customers so there's that, and my experience with non frozen or overpriced KT120s worked out fine.

@Wolf .... of course not Wolf. Many reputable vendors match tubes. It just happens to be IME that ARC matched power tubes bias much easier in my amp. Btw, for the sake of clarity, I am referring to KT-120s.

As an fyi, my amp has a bias "set" tube and a "slave" companion for each pair of tubes, which are configured in push-pull topology. The way the tubes are biased is that I can adjust bias (65 mV)for the set tube, but not the slave.

If the tubes are well matched, the slave will show a bias voltage ranging between 57 mV and 73 mV. If the slave tube bias is out that range, the amp will not operate within spec.

As I said, even though I have bought "matched" tubes from private venders, sometimes the slave doesn't fall within the spec range. IME, this hasn't occurred with ARC spec'd tubes.

Now, as to the KT-150s, that's right, ARC has not blessed using that tube ... yet. Will it work?? Dunno. Some have tried it in their ARC amps and report great results. Will it hurt the amp? Dunno. Will just have to wait for ARC to approve the tube.

Wolf ... like most A'goners, my gear represents a significant monetary investment. In particular, my amp is a pricey piece of kit. Maybe I'm just being over-cautious, ... but until ARC says the KT-120 will not damage my amp, I'm not experimenting. I will defer gratification.

Cheers.