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Old December 1st, 2012, 05:55 AM   #1
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Lav gain problem

I plug my Giant Squid lav into a Zoom H2 and then use the headphone out to an XLR adapter to my Panasonic HMC150. I have the Zoom set to high gain and have my camera gain maxed. Even so, I often have to add gain in post, so I have very little control. I wish I could skip the Zoom altogether, Thoughts?
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Old December 1st, 2012, 06:20 AM   #2
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Re: Lav gain problem

You seem to be presenting two different issues. First is the curious case of the low signal levels, and second is your desire to skip the Zoom H2.

As for the second (eliminating the intermediate equipment, i.e. the Zoom H2), you could use a simple device to adapt the 3.5mm plug-in power connector from your Giant Squid mic to the conventional XLR inputs on your camcorder. Naint makes a variety of adapters like this: Naiant - Inline Devices (bottom of the page).

However, the first issue (the low signal levels) seems like a bigger problem that will unlikely be remedied by skipping the H2, In fact, it will probably be worse. How are you using the microphone? What are you recording the sound of? How do you know the Giant Squid microphone isn't just malfunctioning? Do you have any other microphones that you can use to substitute for troubleshooting purposes?
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Old December 1st, 2012, 06:31 AM   #3
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Re: Lav gain problem

Quote:
Originally Posted by Dana Salsbury View Post
I plug my Giant Squid lav into a Zoom H2 and then use the headphone/line out to an XLR adapter to my Panasonic HMC150. I have the Zoom set to high gain and have my camera gain maxed. Even so, I often have to add gain in post, so I have very little control. I wish I could skip the Zoom altogether, Thoughts?
Most likely it's a mis-wired cable from the Zoom to the camera. The headphone/line out is an unbalanced stereo TRS with left on tip, right on ring, common ground on sleeve. An XLR input is balanced mono with signal hot on pin 2, signal cold on pin 3, ground on pin 1. The typical TRS to XLR adapter wires tip to pin 2, ring to pin 3, sleeve to pin 1. When you use it in the manner you stated, you put the left channel on pin 2, right channel on pin 3. In a balanced input circuit pin 3 is phase inverted and mixed with pin 2, meaning you're inverting your right channel and mixing in with the left to produce a partial cancellation of much, if not most, of the signal.

You also have a levels mismatch. The Zoom's line out is a consumer line level, nominally -10dBv. The camera's XLR line input expects closer to a pro line level, wanting a nominal 0dBu. Combining a lower than nominal signal with the cancellation....l.

What function does the Zoom perform in your workflow? Are you using it to actually record your sound double system or are you using it as a kind of kludgy mic adapter/mixer while the camera records actual production sound?

Is your Giant Squid lav one of the battery powered models or does it need plug-in power? What connector is on its cable?
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Old December 1st, 2012, 07:14 AM   #4
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Re: Lav gain problem

Yes, I think Mr. House called it correctly. I agree that the connection between your Zoom headphone and the camcorder mic input is almost certainly wired improperly for what you are trying to do.

However you didn't mention what the levels are indicating on the Zoom? If you are not clipping on the Zoom even at full gain, then there still might be something wrong with the microphone or the way you are using it.
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Old December 1st, 2012, 04:02 PM   #5
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Re: Lav gain problem

I watched a Curtis Judd review of the Giant Squid omni lav just yesterday, where he compared it to the Audio Technica ATR3350, and he spoke about the former having appreciably more output than the ATR3350, so Im guessing youd expect to see a decent signal into the Zoom H2

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Old December 2nd, 2012, 02:13 PM   #6
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Re: Lav gain problem

Wow, guys, thanks!!

From the YouTube video it sounds like my Giant Squids are okay. He was using a different Zoom, but with great results. (I have four of them, so that's nice to hear! I've also tried all of them)

>What function does the Zoom perform in your workflow?
Until I learned what you know, it was a go-between to power the squid lav for wireless in-studio talking head.

>Are you using it to actually record your sound double system or are you using it as a kind of kludgy mic adapter/mixer while the camera records actual production sound?
Kludgy. Although I get a better signal if I record to an SD on the Zoom and sync in post.

>Is your Giant Squid lav one of the battery powered models or does it need plug-in power?
No Battery.

>What connector is on its cable?
It's all 3.5 until it hits the 3.5/XLR adapter.


So I could forget the camera connection and just record to the Zoom or I could get a Naiant adapter as a go between. I'm not opposed to a higher dollar system ( <$500 ), though I'm not interested in wireless.

You guys are so kind.
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Old December 3rd, 2012, 06:27 AM   #7
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Re: Lav gain problem

Quote:
Originally Posted by Dana Salsbury View Post
...
>What connector is on its cable?
It's all 3.5 until it hits the 3.5/XLR adapter.


So I could forget the camera connection and just record to the Zoom or I could get a Naiant adapter as a go between. I'm not opposed to a higher dollar system ( <$500 ), though I'm not interested in wireless.

You guys are so kind.
Actually was asking it the mic cable was terminated in a 3.5 mono TS, 3.5 stereo TRS wired so the mic signal would go the both left and right channels in the recorder, 3.5 TRS wired mono with the mic signal appearing on the left channel only, or TRS wired for Sennheiser wireless.

That Naiant PFA adapter mic ought to work out okay but you still need to know whether to get the mono TS jack or the stereo TRS jack.
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Old December 3rd, 2012, 07:34 PM   #8
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Re: Lav gain problem

It's stereo. I'm not sure why it's stereo. Here's a pic:

http://www.giant-squid-audio-lab.com...k_NTP3RC-B.jpg
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Old December 4th, 2012, 05:15 AM   #9
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Re: Lav gain problem

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Originally Posted by Dana Salsbury View Post
It's stereo. I'm not sure why it's stereo. Here's a pic:

http://www.giant-squid-audio-lab.com...k_NTP3RC-B.jpg
And if you record in your Zoom, does the mic signal appear on both the left and right channels or just on the left channel?
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Old December 6th, 2012, 10:44 AM   #10
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Re: Lav gain problem

I use the mono setting in the Zoom menu.
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Old December 6th, 2012, 11:30 AM   #11
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Re: Lav gain problem

Quote:
Originally Posted by Dana Salsbury View Post
I use the mono setting in the Zoom menu.
If you used the stereo setting what would you get? I\m trying to figure out if the ring on that plug is connected to the tip so the mic signal goes to both the left and right channels when plugged into a stereo input (like with the stereo plug on the mono Rode Videomic) or if the ring is unconnected (or grounded as it would be if set up for a Senn G2 wireless) and the mic's signal goes only to the tip and thus to the left channel only.
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Old December 6th, 2012, 02:20 PM   #12
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Re: Lav gain problem

As I recall, the Zoom sums both stereo inputs to both channels, regardless whether anything is plugged-in or not, so noise would be added if only one channel was plugged in.. It does not have a 'single track' mono-file mode like the Tascam and Marantz.
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Old December 7th, 2012, 03:46 PM   #13
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Re: Lav gain problem

Yes, I tested it and stereo does the same as mono, which makes me wonder why I bother changing it! :oP
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Old December 8th, 2012, 06:25 PM   #14
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Re: Lav gain problem

Dana,

Here's a very specific question which I think nobody has asked.

If you connect only the mic to the H2, set the H2 to record in stereo, set the gain to high (as you indicate you've been doing), and then make a recording on the H2... how are the levels?

Specifically, where do they peak on the H2 meters, while recording?

And if you then play back that file directly, where do the levels peak while playing back?
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Old December 8th, 2012, 11:11 PM   #15
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Re: Lav gain problem

Interesting question. So the levels might peak on my zoom and not quite peak in Final Cut (or vice versa)?

I usually have good success at weddings laving both the groom and officiant on high. If the officiant peaks (which is rare) the groom's mic will get him at a good level, and if that fails I have a third Zoom (sans lav) on the PA at low gain.
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