Considering the price of new top quality tube preamps $1250 does not seem that high. Most commonly used tubes are available readily, did CJ use an exotic one in this design? They usually use mainline ones. The SUT question is hard to answer, many like to use them even if they have enough gain without them. Why not contact CJ and see what they say.
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Stepup devices (transformers or head amps) are not usually used with 4mv cartridges, and if you were to use one you would have to choose it carefully to avoid the possibility of overloading it. Also, the Premier 3's 40db phono stage gain spec is very reasonable for a 4mv cartridge.
Given that gain is a reasonable match to cartridge output, what determines the amount of hiss that you hear is not the amount of gain but the signal-to-noise (s/n) performance of the phono stage, whether it is internal to the preamp (as in this case), or external. The s/n spec of 72db ref. 10mv input that is given in the Stereophile review is meaningless, because "weighting" is not specified. But judging by the review comments re 2mv I suspect that the hiss levels you will hear might approach being objectionable, particularly if you are listening to wide dynamic range material such as a lot of classical music (in which case you would be setting the volume control much higher than for dynamically compressed material).
That could probably be helped if you were able to obtain and substitute particularly low noise tubes in the preamp's phono stage. Alternatively, although it would involve significant expense, you could purchase an external phono stage that provides better signal-to-noise performance, and connect it into a line-level input.
Re your last question, availability of the 12AX7, 5751, and 5965 is not a problem. The major online tube sellers should have all of them, at reasonable prices except perhaps for some of the most sought-after NOS versions.
Important follow-up to my previous post:
After looking more closely at the Stereophile review, I see that their statement about marginal noise performance with a 2mv cartridge was with a 28db head amp in place, ahead of the preamp. Given that, the review undoubtedly omitted a decimal point, and intended to refer to 0.2mv cartridges, not 2.0mv cartridges. And the noise performance was most likely reflective mainly of the head amp, not of the preamp.
The Koetsu Black, which they referred to as providing marginal noise performance when fed straight into the Premier 3, is (and I believe was) a 0.6mv cartridge, according to the cartridge database at vinylengine.com. The low output Dynavector's and Accuphases's which Stereophile referred to as working unacceptably when fed straight into the Premier 3 had outputs in the rough ballpark of 0.2 or 0.3mv.
So I suspect that you will be fine with a 4.0mv cartridge, if that is indeed what it is.
Thanks for your feedback,especially Al for your research. I double checked the box my cartridge came in and it is A MC Gold and the output voltage is 0.4mv as Goldeneraguy suspected. I think Al was A little suspicious also. Unfortunately my error probability changes everything, sorry about that. I don't want to spend more money and put another component in the signal path. Based on my new information and what Ive read so far Im guessing Ill need A step up device. Ill also contact CJ and see what they say. This problem is new to me, do I have A user unfriendly cartridge that will be a problem with most preamps? Vinyl is my only source so I guess I have lot to learn. Thanks, Billy
I wouldn't say that it's a user unfriendly cartridge; it's just that some preamps include a gain stage suitable for use with low output moving coil cartridges (especially many of the more expensive preamps), and some don't (especially many of the less expensive ones).
Unfortunately, though, I would say that with a 0.4mv cartridge and the preamp's 40db phono stage, which is obviously intended for higher output cartridges, you most likely will need either a step-up transformer or head amp. And that would seem to be confirmed by the statements in the review that a 0.6mv cartridge was marginal.
Although if your listening is just to music that never gets very soft, such as most rock recordings, it seems conceivable to me that the results (in terms of hiss level) might be tolerable.
But do also reconsider the possibility of adding an external phono stage, and running it into a line level input of the preamp. You can find a number of them that I understand to be well regarded at Audio Advisor, in many cases for less than the price of a quality transformer or head amp. Several of the models that are listed as mm/mc compatible cost well under $200.
I looked at Bobs devices site. It is very informative but I will reconsider A external phono stage after all for several reasons. Ill have A larger selection of preamps to choose from (many do not have a phono stage at all). And I wont have to worry if my cartridge is compatible or not.Make sense? Billy