naturerecordists
[Top] [All Lists]

Re: low rec levels with Telinga?

Subject: Re: low rec levels with Telinga?
From: Walter Knapp <>
Date: Sun, 20 Jul 2003 16:06:48 -0400
oryoki2000 wrote:
> A colleage in South America wrote recently
> describing a problem using a Telinga mic with
> a digital recorder.  
> 
> The problem is that recordings made using
> the monaural Telinga "Science" mic and parabola
> and the HHB Portadisc capture bird songs at 
> much fainter levels than when the Telinga
> is used with a Sony cassette tape machine.  
> The recordings are audible, but are 
> not as loud when played through headphones, 
> and they display lower levels when viewed via 
> a computer sound editing program.    
> 
> When I first heard of the problem I thought
> maybe the mic cable was plugged into the line-in 
> port, or maybe some sort of attenuation was 
> turned on.  But the same result occurs when 
> the Telinga is used with a different cable 
> and a Sony consumer minidisc recorder.
> 
> Any other Telinga owners experience something
> similar when they moved from analog to
> digital recording media?

With the HHb Portadisc I often have to set the mic input on -15dB 
attenuation if the subjects are reasonably close. Even then I'll only 
have the gain half way up or so. The telinga is a "hot" mic.

He should check his input settings to make sure it's on mic with 0 
attenuation set, and that his gain setting is at least half way up. Also 
verify that the Telinga is charged, about the only symptom of running 
out of charge is decreasing output.

Also, he should set the Portadisc on Stereo in the system settings and 
see if that fixes it. If it's set on mono, then the design assumes the 
mono signal is fed in both channels and adds them, so they attenuate it 
6dB to keep it from overloading. (a 0dB signal added to another 0dB 
signal will result in doubling the signal, 6dB of overload) 
Alternatively he may be able to set up a splitter to feed both channels 
the signal he wants, as long as that splitter does not cause any signal 
loss, or at least a lot less than 6dB loss.

In a previous discussion in the group a suggestion was made to HHb that 
it would be nice to be able to choose one or two channel mono input, to 
be able to turn off the attenuation when not needed in other words.

If he's setting the Portadisc on mono, but feeding both channels of the 
dual science, be aware that's two different mics facing opposite ways. 
It is not a single mono mic feeding two channels. Adding the two may 
give strange results. He definitely should set it on stereo then, and 
decide which channel to use after he gets it recorded. Bring it in to 
the computer, listen to each channel separately.

This really has nothing to do with digital vs analog. It has to do with 
learning a mic and machine. A analog setup designed similarly would have 
the same effect.

Walt





________________________________________________________________________
________________________________________________________________________

<Prev in Thread] Current Thread [Next in Thread>
Admin

The University of NSW School of Computer and Engineering takes no responsibility for the contents of this archive. It is purely a compilation of material sent by many people to the naturerecordists mailing list. It has not been checked for accuracy nor its content verified in any way. If you wish to get material removed from the archive or have other queries about the archive e-mail Andrew Taylor at this address: andrewt@cse.unsw.EDU.AU