? Tube Replacement Question ?

Mapman,

Thanks for the suggestion. I spoke with Calvin at ARC a few minutes ago. He claims that the useful tube life in the SP16 preamp is 3K - 4K hours. I realize that this is just a rule-of-thumb, but that puts my OEM tubes over the top. Although rearranging the tubes might very well decrease the audible hiss, I am equally concerned about the deterioration of sound quality that I might have become accustomed to over the years. So, I think replacement is in order. Rather than "rolling the dice" with NOS, I will likely order directly from ARC.

BTW, one other question: Is it money well-spent to replace all of the tubes with low-noise types or just replace the input tube with a low-noise (& regular tubes for the others)? I realize that the answer can be quite subjective. But, is any audible benefit worth the extra cost? Thanks you, all.

Some years back a friend who was not a "tinkerer" bought a used Hybrid ARC line preamp. Not being sure how old "the" tubes was he contacted ARC and purchased the correct replacement from them directly. It took me some weeks to convince him to let me take the cover off and try one of my old RAM tubes. When we finally did his jaw dropped. No question that immediately it was quieter.

You will find it WELL WORTH the cost, to replace all the tubes with certified, "Low Noise" tubes. If you use the phono stage; they are a must, in that position. The higher the gain of the stage, the lower the noise necessary. If you are not using the phono stage, you won't notice any noise with older or noisy tubes, in that stage.

Considering all of the varied opinions & recommendations regarding aftermarket & NOS tubes, I am admittedly a bit reluctant to "tinker". Maybe this is my way of admitting that my audio system is more of a source of quality listening pleasure rather than an end in itself. Nevertheless, I appreciate Samujohn's point. When it comes to motorcycles & photography, some of my expenditures are hard to justify to the non-enthusiast.

I do not doubt that other tubes might very well be more pleasing to my ear. But I am unwilling to find out which ones they are by trial-and-error. It seems like there are too many variables that affect sonic quality to keep the risk of getting the "wrong" tubes low. Please correct me if thinking is unsound (pun intended).

"Only an expert reseller can tell who actually made a tube, or its condition.”

That’s also my opinion. Bargain hunting for tubes by the inexperienced is likely to turn out less satisfying and more costly in the long run. In addition to the variety and quality of tubes that they have in their inventory, the advise and integrity of the best resellers make it well worth the premium you pay. In fact, I would suggest that if one has a well set-up, high quality tube system, a call to one of these experts is almost requisite.