Audio Levels on FX1 too low? at DVinfo.net

Matt Vanecek · January 23rd, 2006, 10:36 PM

I was doing a side-by-side shoot with my GL2 and my new FX1, and one of the tests involved using the on-board microphones in auto mode. I noticed that the GL2 sound was much louder and richer than the FX1 sound, using the internal microphone.

When I bring the clips into my NLE, the unaltered GL2 sound is averaging about -12dB, with peaks up to -9dB. The FX1 unaltered sound is averaging about -24dB, and peaked at about -20dB (never reached -18dB). That's a HUGE difference!!

Is this expected behavior on the FX1 internal microphone, or do I maybe have a defective unit?

Thanks,
Matt

Mark Utley · January 24th, 2006, 01:08 AM

My Z1's auto audio is a bit low. I shot some footage of a person speaking today with my Sennheiser ME66 with the audio set to manual and it turned out great.

Tom Hardwick · January 24th, 2006, 03:37 AM

It's interesting to note that the Z1's and FX1's audio recording is not on a par with the GL2's. That's because the GL records PCM sound, whereas the HDV cams record a very compressed MPEG audio signal.

Mark Grant · January 24th, 2006, 07:19 AM

Quote:

That's because the GL records PCM sound, whereas the HDV cams record a very compressed MPEG audio signal.

I haven't recorded sound on a GL2, but the Z1 audio is vastly superior to that recorded by my old TRV900. In fact, I've been editing low-budget shorts and features for a friend for years shot on DV, DVCAM, Digibeta and HDV, and the best dialog audio we've ever had came from the Z1.

There are far more important things to worry about when recording sound than MPEG vs PCM: like noisy preamps, noisy locations and deaf sound recordists.

Matt Vanecek · January 24th, 2006, 07:47 AM

I haven't tried shooting DV yet, but the sound is still quite low according to the on-board level meter. My main concern is, is the internal sound on the FX1 naturally really low, or is it a defect. Seems like some are saying it's naturally really low, which I can work around. If it were an unusual thing with most people's FX1's, then I would give the vendor a call (still within 30 days).

I'm not sure that the FX1 vs. Z1 audio would be a valid comparison, as the Z1 seems to have much better audio controls. But maybe they both use the same internal mic circuits...

Anyhow, I think I'll try a comparison of my external on FX1 vs. GL2 internal, using auto gain and then manual gain. Wish I had a constant dB tone generator....

Thanks,
Matt

Mark Grant · January 24th, 2006, 07:51 AM

Not sure, I almost exclusively use manual audio levels.

Matt Vanecek · January 24th, 2006, 08:01 AM

Quote:

Originally Posted by Mark Grant

Not sure, I almost exclusively use manual audio levels.

I'll try that after work (which I'm late for....). Set both cameras to 5, record some audio, and see how it works out. The stick an external stereo mic on the FX1, same level 5, and see how it works out.

Are there any mic mounting brackets for the FX1?

Thanks,
Matt

Ben Bixby · January 24th, 2006, 11:58 AM

The stock mic is horrible (at least i think so)...Definitely pick up an aftermarket shotgun mic or wireless mic....they work much better!

Matt Vanecek · January 24th, 2006, 08:43 PM

I guess there's nothing for it. I did some quasi-scientific testing. I have a metronome/tone generator, and I set that on C. I tested both GL2 and FX1 with the on-board, auto and manual, and with a Nady CM-2S, auto and manual. This is the results of the camera's as compared to each other, and not to the actual dB level of the tone being generated. Here's what I'm seeing from the dB levels in Audition:

Camera___FX1____ GL2
Int Man. -19.25dB_ -11dB
Int Auto -22.5dB__ -6.5dB
Ext Man. -12dB___ -17dB
Ext Auto -15.5dB__ -13.5dB

I had the FX1 manual set to level 5, and the GL2 manual set to as close to midpoint on the dials as I could get it.

This tells me that the FX1's internal mic blows chunks as far as levels go, while the GL2's internal mic is pretty decent, as far as on-boards go. On the external mic, with manual control the FX1 seems a little more sensitive, but the dials on the GL2 are not marked, so I'm just assuming that the midpoint is analagous to 5. For the External Auto, it seems that the GL2 is more sensitive, but 2dB difference probably isn't that big a deal. It seems FX1 was consistently less sensitive overall, except for that one External Manual, which could just be a result of not setting the GL2 gain up enough (middle is middle, I figure...)

For all tests, I captured directly to Premier Pro from the camera. For the external microphone test, I set the tone generator and microphone up and did not move either one. For the internal test, I set the generator about a pencil length (didn't have a ruler...) from the camera's mic. I elevate the GL2 a tad to put it's mic at the same height as the FX1. The FX1 was in HDV mode. The numbers above are an approximation--between the valleys and the peaks of the audio signal. And, of course, this was done in my home office, and not a sound booth.

Not sure that this is the best way to test anything, but it's what I got. I must say I'm pretty disappointed in the audio handling on the FX1--but then, I've had the freedom of using the GL2's onboard when I had to and still getting decent results. Hope someone else will find this, well, mildly interesting, anyhow....

So, to the second question I thought I asked, what are people using as a microphone mount on the FX1, when it's necessary to have the mic mounted on-camera?

Thanks,
Matt

Mark Utley · January 25th, 2006, 11:17 AM

I was recording some footage of a band in a recording studio last night, using my Z1 and Sennheiser ME66. I had the mic coming through both channel 1 and 2, but with 1 on automatic and 2 on manual. The levels on 1 were really low but this actually helped me out quite a bit. Everyone was goofing around and there was the occassional yelling, so the audio clipped a few times on 2. However, since I still have the audio from 1, I can bring it up and fade down 2 when things get too loud.

I'll probably always shoot things that way from now on when I've just got one mic.

January 23rd, 2006, 10:36 PM	#1
Matt Vanecek Major Player Join Date: Jul 2005 Location: Denton, TX Posts: 334	Audio Levels on FX1 too low? I was doing a side-by-side shoot with my GL2 and my new FX1, and one of the tests involved using the on-board microphones in auto mode. I noticed that the GL2 sound was much louder and richer than the FX1 sound, using the internal microphone. When I bring the clips into my NLE, the unaltered GL2 sound is averaging about -12dB, with peaks up to -9dB. The FX1 unaltered sound is averaging about -24dB, and peaked at about -20dB (never reached -18dB). That's a HUGE difference!! Is this expected behavior on the FX1 internal microphone, or do I maybe have a defective unit? Thanks, Matt

January 24th, 2006, 01:08 AM	#2
Mark Utley Major Player Join Date: Mar 2004 Location: Toronto, ON, Canada Posts: 479	My Z1's auto audio is a bit low. I shot some footage of a person speaking today with my Sennheiser ME66 with the audio set to manual and it turned out great. __________________ Mark Utley

January 24th, 2006, 11:58 AM	#8
Ben Bixby Regular Crew Join Date: May 2005 Posts: 75	FX1 stock mic The stock mic is horrible (at least i think so)...Definitely pick up an aftermarket shotgun mic or wireless mic....they work much better! __________________ Ben Bixby benbixby@mac.com

January 24th, 2006, 08:43 PM	#9
Matt Vanecek Major Player Join Date: Jul 2005 Location: Denton, TX Posts: 334	sigh.... I guess there's nothing for it. I did some quasi-scientific testing. I have a metronome/tone generator, and I set that on C. I tested both GL2 and FX1 with the on-board, auto and manual, and with a Nady CM-2S, auto and manual. This is the results of the camera's as compared to each other, and not to the actual dB level of the tone being generated. Here's what I'm seeing from the dB levels in Audition: Camera___FX1____ GL2 Int Man. -19.25dB_ -11dB Int Auto -22.5dB__ -6.5dB Ext Man. -12dB___ -17dB Ext Auto -15.5dB__ -13.5dB I had the FX1 manual set to level 5, and the GL2 manual set to as close to midpoint on the dials as I could get it. This tells me that the FX1's internal mic blows chunks as far as levels go, while the GL2's internal mic is pretty decent, as far as on-boards go. On the external mic, with manual control the FX1 seems a little more sensitive, but the dials on the GL2 are not marked, so I'm just assuming that the midpoint is analagous to 5. For the External Auto, it seems that the GL2 is more sensitive, but 2dB difference probably isn't that big a deal. It seems FX1 was consistently less sensitive overall, except for that one External Manual, which could just be a result of not setting the GL2 gain up enough (middle is middle, I figure...) For all tests, I captured directly to Premier Pro from the camera. For the external microphone test, I set the tone generator and microphone up and did not move either one. For the internal test, I set the generator about a pencil length (didn't have a ruler...) from the camera's mic. I elevate the GL2 a tad to put it's mic at the same height as the FX1. The FX1 was in HDV mode. The numbers above are an approximation--between the valleys and the peaks of the audio signal. And, of course, this was done in my home office, and not a sound booth. Not sure that this is the best way to test anything, but it's what I got. I must say I'm pretty disappointed in the audio handling on the FX1--but then, I've had the freedom of using the GL2's onboard when I had to and still getting decent results. Hope someone else will find this, well, mildly interesting, anyhow.... So, to the second question I thought I asked, what are people using as a microphone mount on the FX1, when it's necessary to have the mic mounted on-camera? Thanks, Matt

January 25th, 2006, 11:17 AM	#10
Mark Utley Major Player Join Date: Mar 2004 Location: Toronto, ON, Canada Posts: 479	I was recording some footage of a band in a recording studio last night, using my Z1 and Sennheiser ME66. I had the mic coming through both channel 1 and 2, but with 1 on automatic and 2 on manual. The levels on 1 were really low but this actually helped me out quite a bit. Everyone was goofing around and there was the occassional yelling, so the audio clipped a few times on 2. However, since I still have the audio from 1, I can bring it up and fade down 2 when things get too loud. I'll probably always shoot things that way from now on when I've just got one mic. __________________ Mark Utley

January 24th, 2006, 03:37 AM	#3
Tom Hardwick Inner Circle Join Date: Mar 2003 Location: Billericay, England UK Posts: 4,711	It's interesting to note that the Z1's and FX1's audio recording is not on a par with the GL2's. That's because the GL records PCM sound, whereas the HDV cams record a very compressed MPEG audio signal.

January 24th, 2006, 07:47 AM	#5
Matt Vanecek Major Player Join Date: Jul 2005 Location: Denton, TX Posts: 334	I haven't tried shooting DV yet, but the sound is still quite low according to the on-board level meter. My main concern is, is the internal sound on the FX1 naturally really low, or is it a defect. Seems like some are saying it's naturally really low, which I can work around. If it were an unusual thing with most people's FX1's, then I would give the vendor a call (still within 30 days). I'm not sure that the FX1 vs. Z1 audio would be a valid comparison, as the Z1 seems to have much better audio controls. But maybe they both use the same internal mic circuits... Anyhow, I think I'll try a comparison of my external on FX1 vs. GL2 internal, using auto gain and then manual gain. Wish I had a constant dB tone generator.... Thanks, Matt

January 24th, 2006, 07:51 AM	#6
Mark Grant Regular Crew Join Date: Oct 2004 Location: Saskatoon, Canada (was London, UK) Posts: 138	Not sure, I almost exclusively use manual audio levels.