I agree that the single pattern plot is a little suspicious, but the noise spec IS VERY good. Just compare some data sheets:
MXL V67G: 20 dB !!!
The venerable
AKG C414 BULS: 14 dB
Rode NTK: 12 dB ±2 dB
Rode NT1000: 6 dB ±1 dB (reputed to ge the lowest self-noise production large condenser) So 7 dB is EXTREMELY low.
Many of the Chinese and Russian large capsules are 18 to 22 dB
(All when stated as EIN, A Weighted)
Also, the freq response doesn't appear to be "seriously spiking", but instead "remarkably flat". Again, compare to any other popular large condenser.
PS: The self noise and sensitivity always tend to interact and balance or compensate. The S/N RATIO for
the AT3035 is EXCELLENT, at 82 dB. What else matches that in the 200, 400, 600, 800 $ categories ?. (
The MXL V67G is only 80 dB)
PPS: The more detailed PDF data sheet shows more frequencies on the polar pattern (pretty typical variation) and confirms that the design IS a "permanently" charge condenser. What are the disadvantages of that design ?
Detailed data Sheet
Peace,
Rick