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-   -   PDX10P Sound Levels (https://www.dvinfo.net/forum/sony-trv950-pdx10-companion/30186-pdx10p-sound-levels.html)

Spyros Sideratos August 6th, 2004 03:11 PM

PDX10P Sound Levels
 
Hi All
I just bought a new PDX10P and shot some test footage. I am happy with the results except for the audio levels. When using the XLR supplied mic on auto the sound level is unacceptably low. When set to manual I need to pump the level to maximum to get acceptable results, thus defeating the versatility of the manual level settings. The internal mics perforrm a bit better, sound level wise, both in auto & manual.
Is my camera defective, is the external mic supplied of bad quality or are all PDX10s performing that way? If they all perform that way what is the remedy? To adjust sound levels in post will take to much time and be too fiddly. If I use an external Senheiser, or similar, mic will the sound levels improve?
Regards from Oz.

Boyd Ostroff August 6th, 2004 05:26 PM

I've seen a similar complaint here earlier but don't remember if it was resolved. I don't know what kind of stuff you're recording, but I have never tried shooting dialog with my PDX-10. I have used the mono mike on one channel while feeding the other from the sound board when shooting our operas.

After getting burned a few times with loud spikes causing distortion I tend to leave the channel from the house board on auto level. This seems to work reasonably well - when the sound guy feeds me a 0dB 1khz tone it registers around -15dB on the PDX-10 meter. I put the on-camera mike on manual and set it around the middle of the volume range which seems to give a comparable level.

But in post I do boost the levels, typically between 6 to 9 dB. The audio still sounds very clean with no objectionable background noise. If you don't want to do this, and if the levels seem too low then you might need a different sort of mike i suppose. Maybe someone else can recommend one?

Spyros Sideratos August 6th, 2004 06:54 PM

Thanks for your comments Boyd.
Any sound recorded, dialog or general background sounds are very low. Never had that experience with any other camera and my conclusion is that there is something wrong with my PDX10.

Ignacio Rodriguez August 6th, 2004 10:46 PM

> Any sound recorded, dialog or general background sounds are
> very low. Never had that experience with any other camera and
> my conclusion is that there is something wrong with my PDX10.

Make sure the hotshoe cable that connects the XLR module to the body of the camera is well seated. It's supposed to make an alarmingly loud click when it fits. I didn't get it right the first time and didn't work.

Spyros Sideratos August 7th, 2004 05:55 PM

I have checked the hotshoe setting. Yes it does make a loud click and then watched the sound bars to see that the XLR is operational. If I play the tape from the camera straight to the TV or the Mac through FCE you can hardly hear the sound. I increased the level by 9db as Boyd suggested and burnt a dvd with seven minutes of my tests. The sound is good and clean. Is that how these cameras are supposed to operate?
Regards Spyros

Boyd Ostroff August 7th, 2004 08:54 PM

Unless I am mistaken, a level of -12dB on digital video should equal a level of 0dB on analog equipment. Digital levels are intentionally held low as anything beyond 0dB causes clipping whereas analog equipment is more forgiving.

Audio is not really my thing.... Perhaps the audio forum would be a good place to ask this sort of question?

Felix Sorger August 8th, 2004 05:18 AM

I did a quick check on the sound today and it seems that I have exactly the same "problem". The external mic is very low (specially in automatic), wheras the internal seems to be ok.. On the PD150 (same mic) the levels are higher. If you switch to manual, I got quiet satifying results, but the risk to peak over is quiet high

BTW: Unless you are recording from any other external source like some line (like Boyd on the Opera) or 'tie-mic' when performing ITVs, connect the external mic to have a "security source" or surrounding sounds would be a good idea, but

- is there a point to use the external mic only as the quality of the internal stereo mic seems to be quiet ok??
- is there any way to get the external mic on one track and the internal mixed up on the other? (guess no and I am dreaming here)

Kevin Clarke August 8th, 2004 07:25 AM

I'm sure you may already have checked this, but...

'INPUT LEVEL' switch on the XLR module: Is it set to 'MIC ATT'? Try 'MIC' if it is...

>To adjust sound levels in post will take to much time and be too fiddly.<

Hmmm. Audio is so often neglected and can make or break whatever you are trying to achieve. Whatever mics you use - cheap or exorbitant - it is, IMHO, worth putting aside plenty of time for audio. A touch of compression; EQ where needed and balancing the levels throughout really makes a difference.

Good luck, and my regards to Oz

K

Boyd Ostroff August 8th, 2004 08:33 AM

I just did a few tests. If you can duplicate these it will tell you whether our cameras perform the same. As to whether these results are reasonable, that would probably be a better topic to discuss in the audio forum...

Using FCP I generated a 1khz tone. I adjusted my studio monitors so I had a Sound Pressure Level of ~85 db sitting at my normal distance. This was measured by my Radio Shack digital sound level meter set for C weighting.

Now I held my PDX-10 the same distance from the audio monitors, used the mono mike on input 2 which I set to automatic. Looking at the audio level display on the camera, it registered about -3 dB. Now I switched input 2 to manual mode and adjusted the gain until the camera display indicated -3 dB. That resulted in a gain setting of 5 clicks to the right of center (there are a total of 16 possible clicks right of center).

Do you have a meter and a tone source such that you can duplicate this test? Here in the US they're available at "Radio Shack" for $50, and would probably be a good investment since sound levels are a concern of yours.

Actually this test makes me feel pretty good and validates some things I'm already doing. When I record opera I use the sound board feed in one channel set for AUTO. I had the sound guy send me a 0dB analog tone and noted the auto level read about -15 dB. I put the mono mike on the other channel set for MANUAL with the gain in the center. I note that this gives a pretty comparable reading to the board feed during the show (eg -15 dB). Just now using my 85 dB 1 khz tone I tried setting the mike level at the center of the scale and saw the camera displayed an audio level of about -15 dB.

Anyway, from the very little that I know about audio, this seems reasonable and the sound quality of the camera sounds good to me. I also recall that when DV magazine reviewed the PDX-10 they singled out the audio as being especially good. I wouldn't think you'd want to draw too many comparisons to audio performance on the PD-150 since it's audio quality has been the subject of a lot of controversy. Perhaps they run the mike at a higher level to overcome a noisy preamp or something?

Hope some of this helps, and let me know if you can do a similar test.

Felix Sorger August 9th, 2004 01:58 AM

thanks for this check,
I unfortunetaly can't perform a test like this, but it sounds really interesting. I do not want to compare the sound with the PD150 (had loads of problems, HISS etc), let's stick to our PDX10...
I am checking out these days more about the sound and therefore as well the levels, but I am not really worried about the low levels I must say. If in any case the levels seems to be too low on the XLR you always can level them manually, if you are using only one mic, then you can even have on track a bit lower and one track some more aggressive...
Kevin, I agree with you, Audio is really important, either the direct sound or the sounddesign in the post - for me it's 50 image / 50 sound, sometimes changing a bit concerning the project of course ;)

Sean McHenry August 10th, 2004 12:15 PM

Something else to consider, are you running this mic to both channels or just one at a time. There is that setting that allows you to capture sound on both L and R (1 and 2) from the Ch 1 source. This may be affecting it but not likely. If it is then there is some sort of preamp issue there I would think.

The other thing to remember is, this is a shotgun mic and not an omni type hand mic. They have a tighter pattern and like a pair of binoculars or a spotting scope, they need to be pointed pretty accuratly at the subject matter. You probably know all that.

I don't know what the published sensativity is on the standard mic. Per the Full Compass web site, here are the specs from Sony on the ECM670. Per Sony this is the mic that ships with all DSR-PDX10 cameras.

http://external.fullcompass.com/ImageFromDB.aspx?imgid=1134&srctbl=doc

Check the pattern and sensativity for more clues. Seems OK though.

Sean

Juan Parra August 11th, 2004 04:22 PM

last weekend, i adjusted my pdx10's line 1 input to -12dB at 1KHz coming from a mixer. i set input to LINE levels.

now, my captured footage in FCP has very low audio levels. should i have used MIC levels?

does anybody have the right recipe?
thanks

juani

Boyd Ostroff August 11th, 2004 05:49 PM

Juan, according to everything I've read you did the right thing. The concept of "very low levels" may be deceiving. What was the reading on the VU meter on the audio mixer. As I understand, it should read 0 dB at the same time as your camera reports -12 dB. Then the assumption would further be that as the sound engineer mixes the program he does so in a fashion that the loudest peaks read between 0dB and +3dB on his analog meter. Obviously if the mix level is low then your recorded level will be low.

I see that you're running FCP. The manual has a very good section (or at least I found it helpful) that discusses this topic. I'm running FCP 3, so it may be covered in a different section if you have a newer version. In my manual this is covered in "Final Cut Pro 3 User's Manual, Vollume 2: Editorial" See the topics in chapter 6 "Working with audio" which include:

Evaluating the audio in your program
Basic audio concepts
Setting proper audio levels
Settings that affect audio in Final Cut Pro

My feeling beyond this would be to raise the generic issue of "what are reasonable audio levels for DV" in the audio forum since I think the concepts would apply to almost any camera.

Ronald Lee August 13th, 2004 03:16 AM

the audio on the PDX10 is very good, very clean.

BUT, it's low if you expect it to be used as a catch all mic.

The shotgun provided has a limited range and direction. Keep that in mind. A simple test would be to just put a larger and higher end mike, like a Sienheiser ME-66 and compare it with the supplied mike and you'll see what I mean.

So you may have to play around to find the optimal distance.

Messing around with the audio levels in manual would be good under well controlled conditions.

Spyros Sideratos August 16th, 2004 11:55 PM

Messing around with the audio levels in manual would be good under well controlled conditions.

Ronald do you suggest using auto not manual sound?
I have tested the sound with a Senheiser connected through the mic input, that particular senheiser did not have XLR, and yes the sound was completely different and much louder. It picked up sound from a wider spectrum. Thanks for your input.


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