- Posted by Simon Byrne
- On April 15, 2016
Good lectern microphones are of critical importance for those events where speech is the primary source.
I’ve been looking to upgrade from the ubiquitous Shure MX412 or Countryman Isomax 4’s so I loaned a pair of DPA SC4098 Supercardiod microphones and toured with them on a recent roadshow.
The 4098’s are part of DPA’s miniature series. The miniature capsule is combined with an interference tube which contributes to the microphone’s directionality (more on this later). They are available in various lengths right up to 1.2 metres as well as flexible options at the top and the bottom of the unit. They are thinner than most competitors so likely more fragile.
As well as the standard XLR output, they are available with microdot connectors. When combined with microdot DPA’s adaptor system, it opens up the possibility of using them with most wireless microphones systems. Fantastic for those events where the lectern needs to be set/struck super quickly.
So, how do they sound? I instantly noticed their smooth frequency right up to the top end where other microphones can become a bit harsh. The frequency response did not break up as presenters went of axis.
I also noticed that they seemed to have a lot of “reach”. That is, I had more gain before feedback with soft and inexperienced presenters.
Now the concept of “microphone reach” should be BS. A
capsule can only convert changes in air pressure that acts upon it. So what is going on? Lower noise floor and more gain before feedback.
Extra gain before feedback can only really be achieved by a genuinely flat frequency response, good off axis rejection and to a lesser extent, minimal phase shift across the audio spectrum.
Unfortunately when looking at a manufacturers frequency response plot, you are nearly always looking at a plot that has been “smoothed”. Usually by a lot. This smoothing (sometimes called a “marketing” filter) hides a tremendous amount of information. So much so that they are close to useless for making meaningful comparisons.
Using Smaart, I produced my own frequency response plots and compared a 4098’s on axis, and off axis frequency response to a Shure MX412.
With the marketing filter applied (IE an octave filter), it is apparent that the 4098 has a gentle rise from 125hz right up to 8khz where it starts to gently drop off. In comparison, the MX412 appears to be flatter from 200hz up to 8khz where there is a slight peak before dropping off.
Frequency response of Shure MX412 vs DPA SC4098, “marketing” (Octave) filter applied
But this is far from the full story…
With out any filtering, we can see what is happening.
Frequency response of Shure MX412 vs DPA SC4098, no filter applied
The difference between the peaks and troughs in the MX412 are as much as 9db whereas the differences in the SC4098 are much less, particularly in the 200-400z and 8-10khz regions. That means a genuinely smoother response which allows greater gain before feedback.
What is really interesting is that that the smooth frequency response is maintained off axis where other microphones really break down.
I have no idea how the Danes managed to get such a consistent frequency response, but they have. The benefits really show up when you are looking for that extra lit bit of gain from that presenter who doesn’t have a clue.
Plosives are under control with the standard windscreen. This is something you often struggle with in cardiod and hypercardiod microphones but with the DPA SC4098, it is does not seem to be a problem.
The DPA SC4098’s are a great step up for those who want to take their lectern sound to the next level but aren’t ready for Schoepes money.