From the Team Avantone thread:
I would like to add, seeing others talking preamps for these mics, I recommend avoiding running UA-5's with the ck-1's, as there is something either with differing impedences, or the UA-5's just don't have quite enough juice to properly run them. I can't say for sure whether it is just the Oade modded UA-5's or all of them, but for some reason they just don't match up well.
Just wanted to give others a heads up if they were considering running that particular combo, as they work beautifully with my V3 and many other preamps as you can tell from the samples throughout this thread.
could you be a little more specific as to why you think the UA-5 is no good for these mics? I don't own a ua-5 or plan on getting one, but i'm just curious as to what issues you have. Have you tried multiple ua-5s? or just one. These are a great entry level (price wise at least) mic and the ua-5 is a good entry level (again, price wise) pre so several newcomers may benefit from more elaboration.
This may even be suited for a thread in the pre/ad section as well, but specifically the problem I've had with my Oade W+ mod ua-5 and the ck1's is this: I cannot get even close to decent levels with the ck1's, with the gain knobs fully cranked the levels only reach about -25 to -20db max.
I cannot speak of other ua-5's(stock/digimod/busman mod/ other Oade's...etc) just mine, as I don't have access to another. I can say my W+ ua-5 gives perfect levels(even clips) at ~ half gain with my akg 414's which has lead me(and avant's support team,from what they said) to the conclusion that the ck1's don't match well with it, be it the phantom current draw or just mismatched impedences. I was not able to wrangle any specific specs as far as the actual phantom requirement in terms of milliamps from avant, so to me that question is open. And like I stated in my above qoute my ck1's work beautifully w/ my V3.
I was able to end up with a good recording using this combo(w+ua-5>ck1) but it took a 23db boost, a good bit of noise reduction(which I would rather not use), and then another db boost(all of this in post) to make it happen. To me that's just too much f'ing around with what should be a clean pull.
I do believe this matter deserves some further investigation, but did want people to know the issue I've had with this setup. I'm not opposed to using a seperate phantom supply if that would solve the issue, I just don't have access to one currently, so don't know if that would help or not. I am sure there are others on this board with more experience than me with the ua-5's(modded or not), and would be very interested to see what others think. I will likely pose this question in the pre section, but think some more specific ck1 specs would be quite helpfull in getting usefull responses.
edited to add current draw info:
Thanks to the Avantone support team for finding the draw info. Their response: The phantom requirment for the ck1 is 48v / 5 mA.
According to the ua5's manual it can power mics up to 48v / 10 mA. So not sure where the problem lies, and I don't know enough about differing impedences to claim that as the issue.
edited again to add:
My understanding is that the Busman ua-5s do not have the issue disscused above, and should work just fine with the ck1's.