Thanks Vicki, that answers that.
Ben
--- In vickipowys <> wrote:
>
> > I'd be interested to see if the boost switch increases the noise
> > along with the HF.
>
> Yes it does.
>
> Vicki
>
>
>
> On 20/01/2012, at 4:06 PM, doctorobotnik wrote:
>
> > Dan
> >
> > I don't remember the source of my opinion on this, but I've always
> > had it in mind that the MKHs have their noise spectrum 'shifted'
> > upwards so that there is less audible noise in the very noticeable
> > 3-5kHz range.
> >
> > For this reason, and despite their excellent HF response, I've
> > always discounted them as good mics to record extreme HF for
> > pitching down in post because all that noise will be transposed
> > into the audible bands along with the signal.
> >
> > I'd be interested to see if the boost switch increases the noise
> > along with the HF.
> >
> >
> > Ben
> >
> > --- In Dan Dugan <dan@> wrote:
> >>
> >> A few weeks ago someone, I think it was David Brinicombe,
> >> mentioned observing HF noise in Sennheiser MKH 20 microphones.
> >> I've noticed it too, when looking at a spectrogram of a quiet
> >> environment.
> >>
> >> This morning we did a comparison of a 3032 next to an MKH 20 on
> >> the carpet of an interior room, covered with some blankets. The
> >> diffuse-field HF boost switch was in the flat position. I used the =
> >> preamps in a Sound Devices 744T. I posted an expanded-scale
> >> picture of the resulting spectrum at:
> >>
> >> http://www.dandugan.com/downloads/Nature_Sounds_Photos/
> >> AT3032_v._MKH_20_noise_via_744T_preamps.png
> >>
> >> Red is Sennheiser, green is Audio-Technica. The down-sloping curve =
> >> on the left is obviously ambient noise. I tried to match the
> >> levels at around 500 Hz. I believe that above 1K we are probably
> >> seeing mic self-noise plus preamp noise. The "hiss" from the MKH
> >> 20 is obvious. I put hiss in quotes because I can't hear this
> >> noise at all. It isn't trivial however. I see that up-sloping top
> >> end in recordings from quiet locations.
> >>
> >> The tonal artifacts in the 3032's spectrum, especially in the
> >> range 400-1KHz are curious. They could be from the mic or the
> >> preamp, not investigated yet.
> >>
> >> My first guess is that the MKH 20 might be equalized in its
> >> electronics to compensate for a naturally rolling-off HF response
> >> of the capsule.
> >>
> >> -Dan
> >>
> >
>
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