Audio Popping/ Cracking???

OK! I recorded a live band tonight. I used various external mics: Large and small condensers, and shure sm57's & 58's. I set them at different locations, and settings throughout the evening. I documented everything.

I didn't use a "shotgun" or the internal mics. I deemed my shotgun about as useful as the onboard of which was bad at any settings previously. Although, thinking now I should have used it as my control mic, being that the band turned out softer than expected.

I will analyze the results I have over the next few days and report to you guys.

The only problem (as I mentioned) was that tonight the band wasn't very loud! At least not as loud as I've been recording lately. I kept pushing their PA up louder! Hopefully it was enough to get the "un-desired" results. Especially with all of the work I put into this!

I'd like to know who had problems with 150 line inputs? And what you used specifically for equipment?

I haven't used the "lines" yet and would like a leg up so I can test them too!

Testing and networking is our best bet to get this issue resolved. Maybe Panny will give us a hard listen if we have some hard, compiled data for them to chew on.

Lets not bicker about this. I know its a frustrating problem but.....We can do this together my DV brothers!
 
Thanks ronedee... looking forward to results.... too bad it was quieter!

1) I had the problem with the line inputs when I first got the camera, soon after it came out (last November, was it?). The camera was fed by a Panasonic RAMSA digital console, connected to various sets of 8-12 mics for different performances. Lowering the output level of the console just a bit, and raising camera gains to compensate, solved the problem, and it hasn't occurred in about 70 recordings with the same setup since then (some of them VERY LOUD, like a 70-person band in a small place, large orchestras, huge percussion groups, loud amplified Jazz ensembles, etc.)

2) Last week I did extensive testing with both line-level test devices that generate all kinds of signals, line level output from a ProTools rig, and output from a Mackie mixer. That's where I determined the +10dBu clipping level of the HMC, regardless of position of the gain pots and the meter indications. Anything over about +10dBu caused the clipping distortion BEFORE the gain pots were applied. Keep in mind that most pro line-level audio devices place their peak indicators at about +14 - +18dBu; a lot of pro digital gear puts 0dBFS at about the same level.

3) Outside of the initial problem in November, and the deliberate testing, I've used the line-ins on two different HMCs, fed by ProTools rigs, the RAMSA, a 744t, an SD302, a PreSonus BlueTube, and Yamaha and Mackie mixers, on close to 150 projectswithout the distortion popping up. Knowledge of the limits of the system has proven easy to apply successfully.
 
Yesterday I shot with 4 cameras of different sorts.
2 hmc 150's
1 dvx100
1 sony HDV

On the HMC150 I had, I used the onboard mics, the dvx100 used the board, and the sony used onboard mics.

So far, with the camera I had I do not hear any pops.

(The only time I ever heard pops, was with a line feed from a board in one channel, and the on camera mic in the other. I no longer have that footage so I can't remember if I had the pop from both the line and the onboard mics.)

Last nights events seems was only about 115 db's for most of the event, then it went to 120 db, with distortion at times from the board that could be heard through the speakers on about 3-4 songs.

My HMC150 camera was set to -60 and I never let the levels get to the red even though the guy working the board kept turning the system up and down to the point of tripping the house breaker several times.

So far I am not hearing any popping out of the camera I was using.

The other HMC150 was on a crane. It was certainly in the red at times as the levels could not be changed easily, or the operator was not watching them closely. When I checked them, the time the board op, turned up the sound, I noticed it in the red, and corrected it.

I am expecting to get popping out of that camera.

......
In a nutshell, it seems as if you may be able to use the onboard mics under 120db
IF you turn the mic setting to -60 , turn on Auto Gain control and stay way below red.

Not a way to get the best audio, but may be a workaround.

For a board feed, it seems as if you have to keep the board way down.
I'm thinking the time it happened to me, it was from an over driven board feed,
where even a pad would not save me, because the clipping was already there.
A pad would only lessen the amplitude of the already rolled off wave form.


I'll follow up when I hear all the footage.
 
Last edited:
ullanta said:
Thanks ronedee... looking forward to results.... too bad it was quieter!

1) I had the problem with the line inputs when I first got the camera, soon after it came out (last November, was it?). The camera was fed by a Panasonic RAMSA digital console, connected to various sets of 8-12 mics for different performances. Lowering the output level of the console just a bit, and raising camera gains to compensate, solved the problem, and it hasn't occurred in about 70 recordings with the same setup since then (some of them VERY LOUD, like a 70-person band in a small place, large orchestras, huge percussion groups, loud amplified Jazz ensembles, etc.)

2) Last week I did extensive testing with both line-level test devices that generate all kinds of signals, line level output from a ProTools rig, and output from a Mackie mixer. That's where I determined the +10dBu clipping level of the HMC, regardless of position of the gain pots and the meter indications. Anything over about +10dBu caused the clipping distortion BEFORE the gain pots were applied. Keep in mind that most pro line-level audio devices place their peak indicators at about +14 - +18dBu; a lot of pro digital gear puts 0dBFS at about the same level.

3) Outside of the initial problem in November, and the deliberate testing, I've used the line-ins on two different HMCs, fed by ProTools rigs, the RAMSA, a 744t, an SD302, a PreSonus BlueTube, and Yamaha and Mackie mixers, on close to 150 projectswithout the distortion popping up. Knowledge of the limits of the system has proven easy to apply successfully.
Click to expand...
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Thanks for that info Barry! That was extensive! It seems as though the "line ins" are acting pretty normal!

Hornets results seem to point to sub-par level controls and db pads in the 150.

I wonder about the a/d converters too? I wish we could look at a detailed schematic of our audio section. That in itself might provide some clues.

I have a recording gig this afternoon, and hope to delve into my stuff tonight!

Thanks again guys! Ron
 
ronedee said:
Thanks for that info Barry! That was extensive! It seems as though the "line ins" are acting pretty normal!
Click to expand...

Well... I wouldn't say "normal," exactly... they require a somewhat lower level than most pro audio equipment. Given that, they act normally.


Hornet - the -60 setting applies more gain to the signal than -50; it's designed for LOWER signal levels. So you may get better results with the -50 setting.
 
I finished watching and listening to my footage. Unfortunately the band(s) just weren't loud enough to get the "nasty".

There were 3 bands playing: 2 slow rock & folk without drums, and the Jazz band with drums just didn't get there. I'd say none of them hit over 100db's.

I had one small segment where I think the small head condenser mics were distorting, but I just can't be sure. It wasn't a long enough clip.

Anyway, the (Sterling USA made) small head condenser mics (similar to the camera's but better) sounded the worst. they were thin and edgy sounding. I believe if pushed, these mics would have distorted with no problem. Pushing the levels up sounded real bad!! No clipping though, just crappy!

The SM57/58's were flat sounding, but all there and workable. I pushed them way up with no real adverse effects. I also buried them in the PA speaker! I don't believe these would distort barring a bomb blast! Just very flat sounding. Post sound tweaks would definitely be required here!

Not surprisingly, the (Shure KSM27's) large head condenser mics were very sweet sounding! They were peaky, but the full audio spectrum was reproduced evenly and wonderfully! IMO these would be the best choice as long as the levels were monitored closely.

As a side note, the bands all sucked!! It was torture listening to that crap for "another" 3 hours!! Can't wait for the death/speed metal band to film again!! J K..LOL

A waste in the sense that I couldn't repeat the dreaded clipping. Hope some of this helps.....Sorry guys. :(
 
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