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Re: MORE MOORE HHB

Subject: Re: MORE MOORE HHB
From:
Date: Sat, 1 Jun 2002 14:30:55 EDT
Dear Walt,

Thank you so much for your message 5/31/02 2:27:37 PM. 

1. Your "picture window-kitchen window" analogy was extremely helpful.

2. "The portadisc can be set to give you a running max level readout in 
numeric form". 

I tried this and it does seem helpful. This measures the "head room" 
available, not the dB level..right?

3. I wrote "I HAVE BEEN TRANSFERRING DATA FROM MY HHB TO MY HARD DRIVE VIA MY 
PANASONIC
> 3200 DIGITAL AUDIO TAPE DECK. I HAVE USED ANALOG OUT OF THE HHB TO ANALOG IN
> TO THE DAT. THE DAT IS CONNECTED DIRECTLY TO MY SOUNDBLASTER LIVE SOUND CARD
> VIA COAXIAL CABLE."

You replied "Some of the noise you are experiencing is probably caused by the 
route
you are using."

However, I used this same transfer process with the TCM so the relative 
"noise level" between these two recorders should be portrayed correctly on 
the spectrogram?

4. For those that have been following my questions and your kind schooling, I 
will paste below our last correspondence which was not through the List 
Server:

I wrote:
"> As a follow-up to the "noise" generated by the HHB, I analyzed some 
recordings that I made on my last trip to Ecuador in which I recorded in 
Stereo using a MONO mic but plugged into
> both outlets with a Y connection. I had the volumes about 12-15 dB 
different for each trac. The "hot" trace was not overrecorded being at about 
-3 dB while the second trac was at about
> -16 or so. I put both tracs on a spectrogram and boosted the amplitude on 
the low volume trac to equal the gain on the high volume trac. The two cuts 
were identical and the background
> "noise" was the same once the volume was equalized, so I don't think that 
the noise factor was caused by "overrecording". I guess the HHB and digital 
recordings in general are just
> slightly noisier? "

 You replied. "I did not expect it was clipping, the usual name for what you 
are
calling overrecording. And finding the same noise on both is indeed proof.

Note if the digital section was at fault then the noise levels would
have differed, been at some fixed level before normalizing most likely.
The fact that they are the same means it's in the input ahead of the mic
pre of the HHb. That's your mic setup, or it really was out there.

BTW, if you were as close as -3dB, it's possible there is still a
clipped wave here and there. Remember the transfer process is not
perfect, and that -3dB could be a lot closer to 0 dB. Try a obviously
clipped section few through your computer input to find out what true 0
dB come through as. It's a little piece of info that's sometimes important."

Thanks again for your valuable help.

John
John V. Moore Nature Recordings








John V. Moore Nature recordings



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