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Gear / Technical Help => Ask The Tapers => Topic started by: crazifyngers on November 18, 2009, 10:04:48 AM

Title: What happened to this recording?
Post by: crazifyngers on November 18, 2009, 10:04:48 AM
I recorded this last night.  good spot.  respectful crowd.  when i got home to listen to it it had what sounded like clipping.  I thought maybe i overloaded the pre or recorder.  When i loaded it up in soundforge it looked like the image below.  The top looks cut off.  Now I know that I saw a thread about this a while ago but after searching cannot find it.  It mentioned using fresh batteries, which i did.  my rig was:

Nak 300 cp1 "actives"> ca-9100> dr-07

I just got the Naks back and since I needed a minixlr input this was the first time using that particular ca-9100.  the -10 attenuator was not turned on.  does anyone know what could have happened?

here is a sample of the raw wav http://www.sendspace.com/file/owsbtl (http://www.sendspace.com/file/owsbtl)
Title: Re: What happened to this recording?
Post by: rhinowing on November 18, 2009, 11:32:15 AM
that looks exactly like the waveforms i get when my battery is low , hmmm
Title: Re: What happened to this recording?
Post by: SmokinJoe on November 18, 2009, 12:11:27 PM
Do you know what Version of CA9100 you have?  The older ones put out something like 3.3v power to the mics which doesn't give the Naks much headroom for loud events.  The newer ones are 8.0V or so, and that's what you really need.

Been down that road with a friend...
Title: Re: What happened to this recording?
Post by: crazifyngers on November 18, 2009, 12:34:35 PM
this is the one run run  run sold.  He told me that it was the 3.0 version that put out true 9v

EDIT
I recorded some lower volume things with the battery I used last night as well as a new battery.  the waveforms look normal that they are even.  Two questions; first is the first picture what it looks like when the signal is overloading? second how can i tell either the version number or voltage output of the ca-9100?  THANKS
Title: Re: What happened to this recording?
Post by: Kyle on November 18, 2009, 05:31:52 PM
Generally when you have 'overloaded' the mic-pre your waveforms are flat across the top and bottom - many people use the term 'stick of butter' becuase that is essentially what they look like. I am not sure what the wav would look like if there was not enough powe(although rhinowing said that underpowered looks exactly like what you have so....)

You could probably determine the output voltage of the 9100 with a multimeter. Version number - I have no idea; pm Chris Church, I suppose. 
Title: Re: What happened to this recording?
Post by: SmokinJoe on November 18, 2009, 08:12:44 PM
If you bought that from Seth that is new one with the full voltage.  I'm very familiar with that.  I didn't realize he sold it.
Title: Re: What happened to this recording?
Post by: tibbsa on November 19, 2009, 11:44:11 AM
That waveform looks very much like what I got at the Boston VH show back in October.  This was with a Visivox preamp/BB, but the conclusion was much the same: insufficient voltage to the mics.  I've since taken a multimeter to it, and indeed, the Visivox was only putting out around 4.25V, whereas an old Sound Professionals battery box (alone) was closer to 7.5V.  (I just measured this off the other end of a 1/8" cable: positive to tip, negative to the ring.  Whether it's entirely accurate, I don't know, but it confirmed what had been hypothesized, so...)