Vicky,
What I meant is that the REC LEVEL dial is an attenuator. So, as long as yo=
u set it to the maximum position of "10" it does not attenuate the signal.=
I believe that the HIGH SENSE setting internally inserts an additional prea=
mplifier stage (or it increases the gain of the preamplifier).
The recording level controls of more expensive recorders work completely di=
fferent. The level controls of the Sound Devices 7xx recorders for instance=
s directly modify the gain of the preamplifier, which is generally a better=
concept.
Regards,
Raimund
> Raimund,
>
> Interesting what you say (below).
>
> But how do I know that the LS-10 is not attenuating the signal when I =
> am using LOW SENSE? (or conversely that it is amplifying it when
> using HIGH SENSE?)
>
> cheers,
>
> Vicki
>
>
> On 14/08/2009, at 5:13 PM, Raimund Specht wrote:
>
> > Hi Vicky,
> >
> > So, it seems that the higher self noise level at SENSE LOW and 16
> > bit is still sufficiently low for these microphones.
> >
> > I think that the problem with the lower LEVEL control settings on
> > the LS-10 (and other similar recorders) is that it is a simple
> > potentiometer (a voltage divider) that attenuates the output signal =
> > of the first preamplifier stage before the signal is further
> > amplified and fed into the A/D converter. In other words, it is not =
> > appropriate to first attenuate the input signal and then amplify it =
> > again (by using the HIGH SENSE setting).
> >
> > For the same reason, it is not a good idea to activate the
> > attenuation pad on the microphone or the recorder while turning up
> > the gain on the recorder at the same time.
> >
> > Cheers,
> > Raimund
> >
> >
> > Vicki Powys wrote:
> >>
> >> Raimund, Klas and all,
> >>
> >> I just compared 16 and 24 bit noise-wise in a quiet room, and I could
> >> hear no difference in noise between them. However there is a big
> >> difference (as mentioned previously) between high sense 2 and low
> >> sense 10, the latter being MUCH quieter. I hear this difference for
> >> both the Telinga stereo mic and the ME66.
> >>
> >> Conclusion: I will stick with low sense 10 as my default setting for
> >> LS-10 with external mics, and stick with 16 bit. Unless I am working
> >> with a difficult bird with soft calls (e.g. Regent Honeyeater) where
> >> my default settings would be high sense 5, 16 bit.
> >>
> >> cheers,
> >>
> >> Vicki
> >>
> >> PS Klas, I am listening to all my tests through headphones.
> >>
> >>
> >>
> >>
> >> On 13/08/2009, at 5:22 PM, Raimund Specht wrote:
> >>
> >>> Hi Vicky,
> >>>
> >>> I can confirm your observations regarding the noise levels on the
> >>> different SENSE HIGH / LOW settings on the LS-10. The input noise
> >>> levels I measured are as follows (see also http://www.avisoft.com/
> >>> recordertests.htm):
> >>>
> >>> SENSE HIGH, LEVEL 10 (16 or 24 bit):
> >>> -122dBu(A) -119dBu(unweighted)
> >>>
> >>> SENSE HIGH, LEVEL 2 (16 or 24 bit):
> >>> -103dBu(A) -100dBu(unweighted)
> >>>
> >>> SENSE LOW, LEVEL 10 (24 bit):
> >>> -121dBu(A) -118dBu(unweighted)
> >>>
> >>> SENSE LOW, LEVEL 10 (16 bit):
> >>> -113dBu(A) -110dBu(unweighted)
> >>>
> >>> Note that both the SENSE HIGH, LEVEL 2 and SENSE LOW, LEVEL 10
> >>> settings provide the same input clipping level of -30 dBu.
> >>>
> >>> So, the bottom line is that one should better not use the SENSE
> >>> HIGH setting for recording louder sounds that require to turn down
> >>> the LEVEL setting. Instead one should use SENSE LOW, LEVEL 10 at 24
> >>> bit resolution.
> >>>
> >>> Regards,
> >>> Raimund
> >>>
> >>>
> >>>
> >>>
> >>>
> >>> --- In vickipowys
> >>> <vickipowys@> wrote:
> >>>
> >>>> Re self noise, I don't think I AM hearing Telinga self noise.
> >>>> Someone contacted me off-group to query my setting of low
> >>>> sensitivity
> >>>> 10 (rather than say, high sensitivity 3). There has been a
> >>>> previous
> >>>> discussion on naturerecordists re this. Using add on mics,
> >>>> including
> >>>> the Telinga and a Sennheiser ME66, I find that there is more fizz
> >>>> when using high sensitivity. Note that this applies to add on mics
> >>>> and not just the LS-10 inbuilt mics.
> >>>>
> >>>> I did a test this morning, using a metronome on front verandah rail
> >>>> (quiet, rural background), standing back 5 metres, with settings on
> >>>> LS 10 at high sens. 2.5 versus low sens. 10. At these settings the
> >>>> ticking levels of the metronome matched exactly. With both the
> >>>> Telinga mic (used open) and the ME66, there was more fizz with the
> >>>> high sensitivity setting, and when I later boosted the low sens
> >>>> recordings by 6 dB, the fizz level still did not equal the high
> >>>> sens.
> >>>> fizz.
> >>>
> >>>
> >>>
> >>> ------------------------------------
> >>>
> >>> "While a picture is worth a thousand words, a
> >>> sound is worth a thousand pictures." R. Murray Schafer via Bernie
> >>> Krause
> >>> Yahoo! Groups Links
> >>>
> >>>
> >>>
> >>
> >
> >
> >
> >
> > ------------------------------------
> >
> > "While a picture is worth a thousand words, a
> > sound is worth a thousand pictures." R. Murray Schafer via Bernie
> > Krause
> > Yahoo! Groups Links
> >
> >
> >
>
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