Behringer T1 Review

Back of the T1
Behringer do not have the best reputation, but I have found some of their kit much better than one might think. Will the T1 tube/valve microphone be a dud or join the growing ranks of surprisingly good budget microphones?

I did a detailed review of the mike here on youtube:
http://youtu.be/Wl8lVYX15_c

In the review I compare the T1 with the AKG Perception 220 which is a similarly priced FET condenser microphone. So - what is all this tube/valve/FET stuff about and what is a condenser microphone?

Here is my take on the subject: Condenser is an old word for what people call a capacitor these days. The condenser word comes form the idea that it stores electricity or 'condenses' it into one place. The construction of a condenser is two conductive plates with a vacuum, air or some insulator between the plates. There are also a special type called electrolytic which has an electrolyte between the plates; these are not relevant here.

Now, an electrical charge can be stored in a condenser because the electrical potential difference between the plates holds them there. In other words, placing a voltage between the plates (referred to as across the condenser) will cause electrons and their strange partners in crime 'holes' to move to opposing plates.

OK - so far so good - but how does all this help make a microphone?
Well - the amount of electricity a condenser sorts varies based on the distance between the plates. So, if one plate is a thin film and the other fixed, sound waves will change the capacity as they bend the thin film and cause electricity to flow in and out of the condenser. This makes a microphone!

BUT - the signal thus produced is exceedingly small. Unlike dynamic microphones, the signal from a condenser capsule is far too low to drive down a cable. So, an amplifier needs to be used right up near the capsule. This can be done using either a field effect transistor (FET) or a thermionic valve. The FET is a lot easier because it uses very low power and low voltage and is reliable and small and cheep. So, why do we still want valve/tube based microphones?

The big question - why do we like tubes?
No amplifier is completely linear. The job of the amplifier in a microphone is a hard one because the range of signal it has to deal with is very large. Consider that the mike has to work if we whisper into it and if it is infront of a guitar cabinet. It might just be tradition, or there might be something physical in it, but people seem to like the non linearity injected by a valve more than than produced by a FET.

I wonder if the difference is actually more that people expect a valve microphone to have a warm, non linear sound. This means the designers have more of a free hand to make the mike sound nice where as a FET based mike is expected to be clinical, so that is what people design them to be. Maybe we shall never know! What ever the situation, the valve based Behringer T1 is much better than I would have expected for the price.

What does is sound like?
Well, you can watch the video. However, here is some more information. One thing that is a bit of a surprise is its different performance at quite and loud sound levels compared to the AKG. At normal speech levels the P220 is brighter with more presence and a load more air. But at very high sound pressure levels the T1 does much better at both very low and higher frequencies. We can see this in the following spectrograms which are from the final roaring sounds from Eat Bass.

Spectrogram for T-1

Spectrogram for Perception 220.
It is visually apparent just how much more low end and high end the T1 is picking up. Yes, the P220 has a bit more at 7KHz, but that looks like an artefact, it might be distortion in the capsule or amp. The result is that the P220 gives a more punchy mid range sound where as the T1 has a more truthful but brittle sound. I believe the T1 is the clear winner for this test, which was a big shock to me. If I was miking up a guitar cab' then, a T1 would be my better choice. For vocals ,where warmth is wanted over clarity, again the T1 wins. If I was miking up something like a flute or high register female vocal then I would pick the P220.

Now for for some more microphone porn' shots followed by the video embedded:

Behringer Power Supply For Tube Mike

Power Supply Rear View

Front of the mike showing the window behind which is the valve
which is glowing.


Here is the video embedded: