"The NTK employs a large 1” capsule gold-plated membrane, with hand-selected twin triode valves. One of the quietest tube mics in the world (< 12dBA self noise). 158 dB SPL handles loud sound sources with ease. Wide 20Hz – 20kHz dynamic range. Class A valve circuitry. Hand-selected and graded twin-triode valve. Dedicated power supply for optimum studio performance . . ." and so on.
I came upon the NTK as part of a large microphone shootout that I was putting together for a Recording Magazine article. Myself and two other listeners gathered almost $30,000 worth of microphones from our local Guitar Center's recording microphone collection, along with another $10,000 from my collection and the studio's gear. Almost as an afterthought, Guitar Center tossed in a new Rode NTK for our comparison testing. At the time, the NTK was going for about $800., discounted, so it seemed fair that we simply include it with the Neumann's, AKG's, Blue's, old Telefunken's, and the rest of the hoard. For a short while, the NTK could be had for less than $500, which might have caused me to do the test differently. I'm glad I didn't.
First, we carefully positioned all of the microphones in a restricted space, calibrated precisely to present the same axis and distance from our signal source for each test. An example of the test setup can be seen in the picture on the right. Unfortunately, this limited us to doing two comparisons at a time, instead of being able to mic one source for every test. I haven't been able to come up with a test that would allow for that kind of precision, so this was the best test I could design.
In the end, we found that one microphone stood out as having added a special quality to the vocal and acoustic guitar recording tests; the Rode NTK. Or maybe, this particular Rode NTK. The voice was more full, richer, more silky through the NTK. The acoustic guitar was fat, present, and clear and even when the test was limited by my guitar talents, it was obvious that this microphone added something incredibly special to the recording process.
My Guitar Center contact assured me that he'd never heard anything but rave reviews about the NTK and I was almost convinced that, if I didn't really "need" a large-element tube condenser, I could always buy one later. However, my distrust of all things electro-mechanical wouldn't let me give back the NTK and I ended up with another microphone in my collection.
I haven't regretted the decision, but I heard, not long after my purchase, that the NTK had become a little less predictable; that Rode's manufacturing process was turning out more "variety" in the NTK and some of those variations were less than ideal. I think the NTK is out of the Rode lineup now and has been replaced by a completely different product. Maybe this early entry mic was a "loss leader" that allowed Rode to position its products as upscale mics in a very competitive market. When they tried to reproduce the NTK to make a profit the quality suffered. I don't know this is what happened, but I've seen it before and I expect to see the tactic again.
Since buying my 1st NTK, I found a 2nd on eBay being offered by an Australian seller with the complete "broadcast package," including a shock mount, a pop filter, misc hardware, and a case. I took a chance and found that this 2nd NTK exactly matched my original mic. So there is hope that you might, also, find one of these rare jewels amongst the lesser versions of the same model. Listen closely, unless you get a great deal, because all Rode NTKs are not equal.