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-   -   Oktava upgrade? (https://www.dvinfo.net/forum/all-things-audio/40356-oktava-upgrade.html)

Ben Chiu March 1st, 2005 03:02 PM

Oktava upgrade?
 
Greetings!

I've been using an AT 873r hyper for indoor dialogue. I'm shooting a short right now with a scene that includes some whispering and a lot of silence and noticed a lot of low-level hiss (camera input is set to manual and 75-85%). I have a couple of questions:

1. Is this low level hiss I'm encountering the "self noise" some of you mention now and then?

2. Would going to a Oktava 012 hyper be worth "upgrading" to for this situation?

I'd like to really upgrade to a Shoeps some day, but at this point, it isn't in the cards. Perhaps there's another suggestion for a hyper I might consider?

Thanks for any and all insights.

Ben

Jay Massengill March 1st, 2005 03:17 PM

What camera are you using and how are you connecting to the camera?
Also, do you mean the AT897 or the AT873r hypercardioid?
The 897 has much lower self noise than the AT873r, but even the 873r has lower noise than many camera recording circuits.
The Oktava is fairly quiet, but of similar sensitivity to both the AT mics that I mentioned. If it's your camera making the hiss, then adding an Oktava won't really help.
Adding some clean gain by using a mixer or preamp would help in that case.

Ben Chiu March 1st, 2005 03:27 PM

Should be 873r
 
Hi Jay:

Yes, it's an 873r. (You're too fast for me! I corrected my typo a couple of minutes after I pressed the post key, but you beat me to it!). :)

Ah, so something like a DXA-8 or Mixpre might help quite a bit even with the 873r? That's interesting. How could I determine whether it's the camera circuitry creating the hiss or not? I'm shooting with a GL2.

Thanks again!

Ben

[edit: Beachtek model number]

Jay Massengill March 2nd, 2005 09:31 AM

How are you supplying phantom power to the mic? It requires full 48 volts. Less than that can degrade its performance.
The GL2 has pretty good sound, better than some but worse than others. The main difficulty is interfacing with it. How are you connecting the mic to the camera?
How far away are you having to boom?
Adding gain will only help if it is the camera circuits that are contributing most of the noise. This may be a case where it's so quiet that it is the mic's self-noise that you're hearing.
Before spending any money, I'd borrow a small mixer like a Mackie or a SoundCraft. Find a way to interface that to the camera. (I can't remember if the GL2 has a line-level input that works during camera-mode.)
If the gain allows you to turn down the camera input and that clears up the noise, then it's the camera. If the gain simply makes the hiss louder at the same rate as the sound you want to capture gets louder, then it's the mic or the ambient noise.
Your choice then is to use a quieter mic. The AT3031 is both quieter and higher output. It does have a more open pattern and is more sensitive to wind and handling noise. The Rode NT3 is slightly less sensitive but quieter (also much heavier). The Oktava is a fair amount less sensitive and not as quiet as the 3031 or the NT3 but quieter than the 873r. The AT897 is also very quiet, although less sensitive... However it can work better in whispering situations because it doesn't have to deal with off-axis coloration since there's no reverb. This is true of all shotguns in interior situations. Alot will depend on how close you can boom the shot.

Ben Chiu March 2nd, 2005 01:01 PM

Phantom power and detective work
 
Greetings Jay:

> How are you supplying phantom power to the mic?

I'm using a Rolls IIb phantom power unit.


> How are you connecting the mic to the camera?

I've got the 873r-->Rolls-->AT100U-->BNC to mini jack cable-->GL2. You just reminded me, perhaps I should try a direct cable rather than going wireless. I'm so used to using wireless connections all of the time, it didn't occur to me that wireless unit might be the cause.


> How far away are you having to boom?

The mic is about 2.5-3 feet away.


> Adding gain will only help if it is the camera circuits that are
> contributing most of the noise. This may be a case where it's so
> quiet that it is the mic's self-noise that you're hearing. Before
> spending any money, I'd borrow a small mixer like a Mackie or a
> SoundCraft. Find a way to interface that to the camera. (I can't
> remember if the GL2 has a line-level input that works during
> camera-mode.)

I don't know if it's line level either. I don't think it does. All it has is a minijack and mic att option.


> The AT897 is also very quiet, although less sensitive... However
> it can work better in whispering situations because it doesn't
> have to deal with off-axis coloration since there's no reverb.
> This is true of all shotguns in interior situations.

Ah! I didn't think of that either (low sound, little reverb). I have a 4073a and will try that too.

Thanks for the excellent advice and suggestions, Jay. I really appreciate all of your help.

Ben

Jay Massengill March 2nd, 2005 02:15 PM

Yes, drop the wireless and go for the 4073a. I'm sure that will cure this situation.


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