United Studio Technologies UT FET 47

Photo: Neil Rogers

UST’s debut large diaphragm condenser mic is a homage to one of the best‑known solid‑state designs around. We put it up against the real thing.

The Neumann U47 FET microphone has become ubiquitous in professional studios for recording kick drums and bass cabinets. A proper studio workhorse, it can also excel on brass, guitar cabinets and louder singers. It’s a slightly curious beast in this regard, as you might reasonably expect a microphone that takes a bit of a hammering to be somewhat affordable. A glance at one of the second‑hand selling sites, however, reveals just how much people are prepared to pay for the original models. The sums involved no doubt encouraged Neumann to release an exact replica of the original model back in 2015. It’s still available, and retails for around £3000$4000. Hugh Robjohns reviewed the reissue and gave an excellent, detailed explanation of the history behind the original design. You can read that at www.soundonsound.com/reviews/neumann-u47-fet.

There’s been a number of recreations of that iconic microphone over the years, but many of those still command quite a hefty price tag. A new American company, United Studio Technologies, are the latest to produce an offering on the theme and their website explains how they spent several years honing their design with one goal in mind: to make a convincing‑sounding, but affordable, U47 FET‑style microphone.

The UT FET 47 is a cardioid‑only condenser mic that features a 10dB pad and a switchable high‑pass filter at 75Hz. Looks‑wise, it’s very, very similar to its German inspiration and in a busy studio session, you’d have to look closely to know it wasn’t the real thing. It’s a solid, professional‑looking mic with a sturdy onboard yoke‑style mount, just like the original. UST explain that they worked closely with capsule designer Eric Heiserman to create a fresh take on the classic K47 design. The result is a dual‑diaphragm capsule sporting 6‑micron‑thick, gold‑spluttered mylar diaphragms, an assembly the team spent several years refining. United also experimented with a number of transformer options before settling, like many audio designers do nowadays, on a large, custom‑wound option made by Californian manufacturers Cinemag.

In Use

I have a Neumann U47 FET reissue at my studio, and I was extremely interested to hear how the UT FET 47 sounded compared to the real thing. My first test was on the application that it is now, arguably, most commonly associated with in professional studios: capturing the resonant head of a kick drum. There are a few reasons why these mics work so well at this job, with the main one being the way the mic’s proximity effect produces a smooth, extended low‑end. This is why you often see these mics positioned so close to a source. The other reason is that they can cope with very high SPLs. The UT FET 47 has a rated SPL of 136dB, or 145dB with the pad engaged.

Spot the difference: the UT FET 47 is placed up against a kick drum, alongside a Neumann U47 FET reissue.Photo: Neil Rogers

Trying to set up as fair a comparison as I could, I positioned the two microphones outside the front of my Rogers 22‑inch kick drum with the capsules as close together as I could physically get them. I then recorded some samples with the mics about an inch away from the resonant head, and another set with the two mics around two feet back. The results were quite striking, and allowing for the fact that the mics weren’t pointed at exactly the same spot they sounded like the same microphone. If I listened very closely, I thought I could hear a tiny bit more presence around the 2‑4 kHz range on the UST mic, but this was no bad thing. Possibly the Neumann sounded a little fuller, but more importantly the low end was, on both mics, present, clean and ready to be incorporated into a drum sound.

The results were quite striking, and allowing for the fact that the mics weren’t pointed at exactly the same spot they sounded like the same microphone.

The other job that keeps our Neumann U47 FET busy is being positioned in front of a bass cabinet. I had a bit of reamping to do so I set up our studio’s Ampeg SVT rig and positioned our Neumann next to the UST mic, just as I did with the kick drum. The results were equally impressive, while that bit of extra presence in the midrange from the UST sounded more pronounced and slightly preferable to the Neumann on the track I was working on. Again, positioned very close to a loud cabinet, the bottom end was full and clear.

My last test was in front of a guitar cabinet for a distorted rhythm part, and as the difference in position can be quite pronounced on a guitar speaker I used some tape to mark a position on the grill covering the speaker. Rather than record both mics at the same time I did two passes of the reamp with each mic in the same position. This test again revealed slight differences in the midrange, with the Neumann sounding a touch brighter on this occasion. There was very little to choose between them though, and they both did a great job of capturing a clear picture of how a loud guitar amp sounded.

I didn’t get a chance to compare the mics on a vocal recording session, unfortunately, but I heard nothing from my tests that would suggest to me that the UST wouldn’t do an almost identical job as the real deal. If you’re interested in hearing for yourself how close the mics sounded in my tests, the files are available at https://sosm.ag/ust-47-media.

Summing Up

The classics are classic for a reason, and if you’ve been on the lookout for a cheaper option to do the job of a U47 FET in your studio then you should consider your search over. The UT FET 47 sounds as close as anyone is ever going to need on the key applications, and is a great‑sounding microphone in its own right. It also looks the part, is very solidly built and seems ready for a few decades’ worth of punishment. If you walked into a studio and saw it on a stand you would just assume it was the real deal. It certainly sounds like it.