improving audio

Hi all,

Is anyone using a triton audio fethead on the bmpcc 4k to address the weak preamps/noise issue on the preamps? The fethead boosts the signal from a mic by + 18db.

Proposed set up: on camera sanken shotgun - fethead - camera.

I have been disappointed by the weak preamps on the cam and am looking for the simplest and lightest solution. Ideally I would like to go line level in but that entails yet more gear on the already overburdened camera. The fethead is light, small, unobtrusive and IF it worked could provide an elegant solution. Of course, all it might do is to boost the self noise of the microphone else.

Cheers

Rob

I'm also interested in a lightweight small solution. I wonder if anyone has also tried IK multimedia's ipre. They claim 10 hours of phantom power operation on a 9v battery although I'm pretty sure pro shotguns chew the juice a lot quicker than your standard condensor mic ...

Are you looking for a solution on camera mounted mic or on boom?
If you are running high quality mics like Sanken, you could get a pre owned MixPre3 and step up the game.
Great mics and poor preamps are not a route to like.

Otherwise Deity have two battery powered mics, the V-Mic D3 and D3 Pro which are low cost and quite decent. The Pro have level controlled output if you really need to keep the weight down.

It is on camera mic.

I really like the Sanken short shot gun. I also have its big brother which has exceptional off axis rejection. I already have a sound devices for double sound when I need it. I am often put in a position where I have to do spontaneous filming and have to rely on the onboard mic. This has worked very well on the Red cam that I have (original MX had quite preamps which are totally useable sound).

My ideal solution is: no onboard additional mic pre, no additional cables, no additional switching on/off, no additional batteries etc. The audio fethead is an interesting device - it passes phantom power through to the mic AND uses it to boost the mic signal by 18 db. The idea is that if the camera's mic pre gets a hotter signal it will not have to work as hard and you wont have to crank up the mic pre when its weakness becomes very apparent with an audible hiss. Apart from being self powered it adds virtually nothing to the weight of the rig and plugs directly into the back of the microphone. What a great solution - IF it worked!

I might have to just order it from B & H and give it a go and can always return it if it does not work.

Rob

Ok, I have ordered one and will you know how it goes.

Just one correction. I have only had the camera for a short time and continue testing with it. The audio through the min xlr input is in fact not bad at all. I attached the bigger Sanken CS 3e shotgun mike and the sound is actually very good and totally usable. I was on about 76% audio volume. It will be interesting to see if the triton enables me to reduce reliance on the camera preamps thereby getting cleaner sound.

RC

Thanks for reporting back.
Looking forward to hear about your experiences with the add on.

Ok, I am as a I said new to the camera and continue to explore its capabilities. I am focusing on audio at the moment though I have to say that I am delighted by the images being produced.

So I turned my attention today to the 3.5 mm input and fed it a signal from a lectrosonic wireless mic system. The lectro enables you to increase the volume of the signal that you feed by 1 db increments. While I generally have this set to -20db for other cameras, for the bmpcc 4k I had to set this to to -10 db and even -8db so that it was quite a hot signal going into the 3.5 mm input. I set the preamps to 55%. i think that this is consistent with what I have read concerning the weakness of the preamps.

Having said that, I must say that the sound recorded was terrific. I would not hesitate to use it. There was no audible hiss or background noise. I am quite delighted by the audio quality and relieved. So the lesson is to work within the particular parameters of the camera and to feed it a hotter signal.

Robert, that is similar to my experience with the Sennheiser EW100 G3 set. After having cranked up the output of the receiver to +12dB I am getting a nice and very usable signal recorded. For other cameras like my Canon XF305 I would use 0dB or less.

Ok, I got the Fethead and attached it to my Sanken CS 1 which requires phantom power.

It works exactly as advertised. It boosts the audio signal very cleanly of the mic to the preamps allowing you to set the volume of the preamps much lower. No degradation of audio quality from the mic. This means that you can hit the sweet spot of the preamps. I had mine on 65 which was plenty for a broadcast level signal.

It is I think a very simple, lightweight and inexpensive solution to the weak preamps problem on bmpcc 4k. $99 from B & H. Photos of the Fethead attached. It plugs directly into your mic.

The Fethead is a good solution for using a single mic per input. But, be careful, their are two models, one for phantom power mics and one for non-phantom mics.

Hello again Robert.


How are you finding the BMPCC4K compared to your original RED One? I have had a "big" URSA lay down beyond economic repair. It was secondhand so one should expect such things. Like the original RED One, it was pretty much self-contained with good audio.

Loved the thing. Skin tone and highlight roll-off was a sweet look out of the camera. Alas it is uneconomic to repair and the parts support for the turret is not there. Folk have suggested I bite the bullet and go the BMPCC4K route if I want to contain costs.

The idea of building all manner of wires and cables and framework around a small cam is a bit offputting when one is used to all being together in one piece. The smaller sensor is also a disincentive.

I have a Sound Devices MixPreD. It has output level controls which enable matching to camera audio systems which do not comply with unity gain line-input standards. It is good with the original BMPCC and SI2K.

Quite right Denny, do be careful to get the right one.

Since writing, I have now used it on several shoots and the thing is a little miracle - unobtrusive, adds little weight, adds no audible noise, and it really is a significant boost to the sound. It sounds almost like a line level signal.

Hi Bob. The Red One was a funny old camera wasnt? Bless Red for making it but honestly I hugely prefer the bmpcc 4k to that clunky old thing. The red ones images were kind of video on streroids and the colour science uninspiring. I much preferred the subsequent Epic camera which I really loved is now ready for retirement.

Cheers