Joemeek TB47

Paul White tests Joemeek's multi‑pattern contender for the valve mic heavyweight title.

Most of the capacitor mics that rival the established names rely on capsules built in China. As the introduction to the TB47 user manual points out, China was one of the countries that benefited from the technology‑sharing policy in the communist world, and when Neumann was split apart by the Berlin wall, the eastern arm of the company (later to become Microtech Geffel) continued to develop microphones based on the original Neumann capsule. It is this capsule design that was adopted by the Chinese engineers and which appears in so many of today's more affordable microphones.

While some manufacturers are content to place their own badge on a Chinese‑designed microphone, others, including Joemeek's Ted Fletcher, handle the majority of the electronic and mechanical design work themselves, then get the mics built in China to keep the costs down. The TB47 is built and inspected in Shanghai, then re‑inspected in the UK before shipping.

Shanghai Surprise

The TB47 offers a choice of nine polar patterns, including omni, cardioid and figure of eight.

Supplied in a rather nice foam‑lined aluminium case, the TB47 comes complete with cables, power supply, foam wind shield and elastic shockmount. It is a traditional multi‑pattern mic where the various patterns are derived by combining the outputs from the dual‑diaphragm capsule in different proportions and phases. Nine patterns are available from a rotary selector on the power‑supply box, ranging from figure of eight to omni via all the shades of cardioid, though there are no low‑cut or pad switches. A multicore cable links from the mic to a seven‑pin socket on the PSU and a balanced male XLR socket provides the audio feed to the outside world.

The mic itself is based around a large‑diameter capsule, with dual gold‑sputtered mylar diaphragms, mounted upon a resilient shock‑absorbing pillar. A single‑layer, tough steel grille protects the capsule and provides RF screening. The rest of the electronics are located inside a separate compartment within the body of the microphone, with an output transformer providing the polarity splitting necessary for balanced operation. I like the fact that no attempt has been made to emulate the cosmetics of any other popular high‑end studio mic — a bright green logo on the black background proudly proclaims that this is a Joemeek product. However, this 'integrity' is somewhat countered by the use of the number 47 in the unit's name...

The apparently dual‑triode valve is the sole source of amplification within the body of the mic — it is a true all‑tube mic rather than a hybrid design such as is favoured by some other manufacturers. I say 'apparently', because the part number of the valve has been removed and I could find no reference to it anywhere in the product literature. Joemeek have developed an 'ultra‑linear' valve amplifier stage, which incorporates the capsule itself in the feedback path with the aim of producing lower distortion. A high‑quality ceramic base is used to house the valve, which fits securely without the need for a restraining clip. Sensibly high‑quality components are used throughout, including generously rated metal‑oxide film resistors.

Overall, the standard of engineering is good, with a tendency towards 'belt‑and‑braces' toughness rather than anything too fancy. There's a lot of heavy, machined brass involved and this is one of the few mics I've tried that would probably double up quite nicely as a weapon! Perhaps there's inspiration here for a studio version of Cluedo — Mr White in the control room with the heavy‑duty valve mic!

As is often the case with large diaphragm mics, the spec sheet tends to be a little vague, with the frequency response quoted as "substantially flat from 15Hz to 20kHz". That doesn't mean much without limits or a graph to back it up, but, then again, a large diaphragm mic sells on its particular sound rather than its flatness of response. The signal‑to‑noise ratio is expressed as 76dB, but again without reference to any signal level or percentage of distortion, while the dynamic range is specified as 128dB. All that these specifications tell you is that you're only going to find out how this mic behaves if you plug it in and listen to it!

In Use

As with all tube mics, the TB47 takes a few minutes to warm up properly, after which it is ready for use. It also pays to be aware that, like all conventional DC capacitor mics, the TB47 will be susceptible to loss of sensitivity and becoming noisy if condensation is allowed to form upon its diaphragm, so using it in a warm environment with a pop shield is advisable.

The first thing I noticed about the TB47 was that its background noise was so low that I'd have had to have been recording very quiet or distant sources to notice it at all. On the other hand, the mic could also handle very loud sound sources, and the lack of a pad switch wasn't really an issue for normal applications. With a quoted sensitivity of ‑36dBV, the TB47 proved to be subjectively similar to the other large diaphragm mics in my locker, so no concerns there either.

Tonally, this is an extremely nice microphone that avoids the boxy nasality of some fixed cardioid models, and retains a pretty consistent sound regardless of the pattern chosen. The mid‑range is exceptionally clean and detailed and is complemented by a smooth, glossy high end. The mic definitely flatters the sound in some way, though there's no obvious coloration. When using anything but the omni pattern, low‑end warmth increases as you work closer to the mic due to the proximity effect, but it never overwhelms the sound.

As you'd expect, the TB47 is particularly good on voice, but I also found it much easier to get a good acoustic guitar sound with it than using my usual choice of mics. Given that this is a rather more expensive mic than the ones I usually use, maybe that isn't surprising, but it does show that even once you're into the 'decent capacitor mic' league, the audible difference between models can still be quite significant.

Summary

The TB47 isn't exactly a budget mic, and if you don't need a multi‑pattern mode, there are cheaper valve mics available in the UK that can achieve similar quality. If you need a multi‑pattern valve mic, then it holds up very well against the obvious competition within its price range. I particularly like the fact that this is an easy mic to work with — you don't have to put in a lot of effort to get a good sound. Straightaway, vocals sound open and natural, but with some hidden magic that flatters in a very subtle and believable way. The same is true of acoustic instruments, and though a small‑diaphragm model might be the purist's choice in this application, the TB47 never seemed to be struggling.

Overall, I liked the TB47 a lot. The cosmetics might not be to everybody's taste, but you can't quibble with the robust construction or the quality of sound, and it's nice to see a mic supplied as a complete kit. Competition is pretty hot in the mic market at the moment, but the TB47 is definitely worthy of a serious audition. It's not just another Chinese mic!