Manley Chinook with (very) low output MC ZYX?

I own a Steelhead; I use it at 65db setting with an AT ART7, which has about the same output as a low output ZYX. You will have no problem. Moreover, I like my low output ZYX UNIverse a bit more than the ART7. 

The nice thing about the 4BSST is that you can change the input sensitivity to 1 volt.  You will need approximately 72db of gain to drive your amplifier to full gain using the 1volt input setting.  The Manley can provide 60db of gain coupled with the Bryston's line level gain of approximately 15db, therefore, you will have a total of 75db of gain available.  You will be fine.

Chakster- I do see other Airy models on Audiogon, but they're far more than the ~$1100 I can get this one for locally.  The Ultimate seems to go for ~$2200 off demo?  Is it that large a difference in sound?

Lewm- I have an SE, but not the SE MkII, so no 65dB setting.  :/

brf- Good point, I had forgotten about this.  I use balanced inputs off of my BP-25, so I am using the lower gain setting currently.  I presume this would result in slightly more noise?  Possibly less than if I had the Manley updated with the +65dB setting though?

Should be fine.  I have an ortofon that is .3 mv and the SE not MKII and have plenty of volume to spare at 60db.

tre, I am getting a bit confused here.  I gather now that your cartridge drives a Chinook which in turn drives a Bryston linestage with an additional 15db of gain after the phono gain.  You've got gain to spare, even if your Chinook itself only supplies 60db max.  I am using the Steelhead as a full function preamplifier, so that the total phono gain in my system is whatever I set on the Steelhead.  At the max of 65db, I have ample gain with the AT ART7.  You've got 10db more gain than I do at your disposal. Of course, keep in mind that the input sensitivity of your amplifiers and the efficiency of your speakers also play a vital role in determining how much gain you need.
Now for my area of confusion: Did you say that you are using the balanced inputs on your Bryston?  But the Chinook is single-ended, so how does that help, unless the Bryston has a circuit or a transformer at its line input that converts the SE to balanced?  If the system were true balanced, using the balanced mode will result in less noise, not more noise.  But as it is, I don't know if you'll have any benefit from the balanced inputs.