Blackmagic Forum

Hi ...

I want to buy Video assist 4K (not fir 4k but only for XLR input )

I ha ve question :

It's possible to merge sound form XLR With video form HDMI ... ?

No, not it is not, you can either use the embedded audio in the HDMI/SDI stream or use the audio input from the XLR, no mixing capabilities between the two. A Video Devices Pix recorder will not merge (mix) audio sources, but it can record up to 4-6 audio inputs on different audio tracks (channels) but not the Video Assist, it can only record two tracks (channels) of audio. However, not sure if you can assign individual tracks on the VA between differen sources, like the Pix does?
Cheers

With video assist is not possible to record ...

Stream 1 vidéo from HDMI input
Stream 2 audio forme XLR

it's impossible ?

You cannot merge sounds, but you can assign one channel to XLR mic (with or without phantom power) and the other to imbedded sound from the video (which can be HDMI or SDI).

If I have camera + micro XLR

I cannot use Assist for record

video from camera HDMI or SDI

and Sound from micro XLR ?

The VA has two audio channels, and Hans states you can take one channel from the HDMI input from the camera, and one channel from the XLR line/mic input, so in this sense, yes you can, but I have not tested this (I had the original VA, not external audio inputs). If this is the case, You will have one audio track/channel from the camera and one track from the Mic/line XLR input. In post you can mix the two tracks into one track if you want.
Cheers

I draw a pic

The Website says it all https://www.blackmagicdesign.com/products/blackmagicvideoassist

Blackmagic Video Assist 4K is also an extremely high quality audio recorder! You get two mini XLR inputs with 48V of phantom power so you can attach external microphones to record audio with Video Assist, instead of your camera. This totally eliminates the problems with auto gain controls on DLSR cameras! With an amazing equivalent input noise floor of -128dBV, you get high quality, crystal clear audio that sounds dramatically better than camera audio! Sound is recorded into the same file as the video so you don’t have to worry about AV sync between separate audio and video files!

thanks

OK, I understand what you are trying to do. As long as you have a video signal, even a blackburst, on the HDMI input, you can record up to two tracks/channels of audio via the XLR inputs, that will be recorded with the video feed. You are able to "turn off" thevaudio in the SDI/HDMI inputs and replace it with the audio being input on the audio XLR inputs. Your original question was confusing the way it was worded.
Cheers

Ok so it's possible if there are only 1 xor channel .. to to a double mono for the vidéo recorded ...

I have 1 xlr
I use only on input BM video assist XLR
Si it's possible have only one side ( maybe Left ou Right )
It's possible to create a double mono ?

Is it possible to record only audio with the Video Assist 4K?

No, you need some type of video signal to record the audio onto. You can use a simple black burst as the video signal, to get timecode and audio recording.
Cheers

Denny Smith wrote:No, you need some type of video signal to record the audio onto. You can use a simple black burst as the video signal, to get timecode and audio recording.
Cheers

I was hoping this could be a sweet 2 channel audio recorder as well. If it could record straight to mp3 it could do different roles on different gigs for me. Pro quality stand alone audio recorders aren't much less than this is [and many are much much more]. Feeding black burst means a separate unit, right? And then I still have final files that have to be processed to yield audio files. And then there is a storage capacity issue as well to hold all that useless video data. Not worth the hassle.

Ultimately, this is a software limitation... MP3 is now free game with no licensing! How about it BM? Add an audio only mode?

You might be able to reference it to itself. Anyone bored enough to try it out? I don't own one anymore.

No, do not think that would work, as I do not think the VA can generate a video out signal, without a video input.
Cheers

I would very much like to see a product update from Blackmagic design to the 4K that allows the merge of HDMI audio with L/R XLR input. At present, you can either select L/R HDMI or L/R XLR or one from each, i.e. L HDMI and right XLR.

This is inconvenient when you are working with HDMI sources that have separate L/R, you lose sound accordingly from the side that you don't select... Not only that, if you do go down the route of using HDMI with XLR, for a decent result you need to do post processing to merge the L/R channel for a clean stereo video with HDMI and XLR sound through both channels..

I think, that this should, be something that is achievable from a software viewpoint, it's just a matter of providing options to merge xlr and mic with gain controls for respective channels.

At present, to work around this I am having to create a somewhat cumbersome solution which is a shame considering how awesome the 4K is. HDMI sound needs to be extracted (I'm looking at using an ARC HDMI switcher for this) with the sound then passed into a Mackie 402, the Mic also passed in to the 402 and combined, then 1/4" out to Blackmagic 4K XLR via a convertor cable (the 802 and 1202 has XLR out but is a lot more expensive).

Although this product appears to be targeted at the professional camera/videography market, there is also a big use case out there for those like myself who wish to use this as a one button no post processing solution for screen/desktop capture (think vlogging), making the merge of sound sources a powerful option.

I'm very happy with the product but feel that the lack of this functionality is somewhat limiting.

Better just buying the product that does what you need straight out of the box rather than hope for an update.

For the OP it's a non issue because DVI doesn't carry audio so there's nothing to merge.

Howard Roll wrote:Better just buying the product that does what you need straight out of the box rather than hope for an update.

Any recommendations?

Also, it wouldn't be an issue for the op with HDMI either, if Op selects HDMI video with XLR L/R. Op wouldn't have had an option for the HDMI audio being passed through (appears to be the goal here).. same outcome as using DVI.

Passing the HDMI signal through could be done, if the HDMI out was just split off the input before processing the signal, but this is not the case. The VA outputs are post process outs from the video/audio processors, and reflect any processing done by the VA.

Also, the VA can not record from both sources at the same time due to hardware limitations, or this would have been possible by now. Features like this, add to the units cost, and BM has gone with a VA product that costs less, and had only the features used in a majority of shooting solutions, forgoing features like multi-track audio mixing.

If you want to merge audio from HDMI/SDI and direct XLR inputs into your video stream, than you need a monitor recorder like the Vide Devices PixE which has audio multi-track capabilities from several sources (Imbeded audio in the video signal, and mix/add two XLR audio input sources, time code support and more. For multi-track audio, you will need to add the optional LR mixer to the PixE 5, which connects to the bottom, and provides a full 2-channel mixer with XLR mic/line inputs. But this unit cost more too!
Cheers

Thanks Denny, I'll take a look at the products you mentioned. I've committed in purchase already to some
of the components that I make reference too in my earlier post (splitting hdmi prior to input and merging in mixer before output) so I'll see how it goes, if it works, maybe it will be a cheaper option for people who end up here seeking something like this (at present, I would say I've spent an additional £150 on the kit)

Unless I'm missing something DVI doesn't carry embedded audio.

If you want to mix audio in the recorder both Atomos and Video Devices will do the job. Even the lowly Ninja Blade allows mixing of HDMI and analog audio, the Ninja Flame is more capable in every way and now that the summer sale is over it's cheaper than the VA4k as well.

Good Luck

Hi Howard,

Thanks for the reply, the Atomos devices look good, especially the sumo . Have you used these for audio merging hdmi and mic sources? I've looked through the spec and don't see much in the way of context on this, would you elaborate on some use cases, pros/cons please.

Thanks


James

It does not MIX!! It does record on different audio channels..

In SDI and so in the container of ProRes and DNxHD you have 16 channels of audio..
The atomos makes use of these channels to record multiple audio channels under the video feed.

You can mix them in post which gives you far more control over your audio then before set audio.. So if a loud pop is happening in the analog audio.. You just pull the analog audio in post for that point of time.. And you still have your embedded audio

That's very cool. Thanks for the clarification.

I'd be more than happy with this. It would be good if this functionality was added into the BMD VA 4K in the future.

No, not likely, as the current VA hardware can not support more than 2-channels of audio embedded in the video stream. It would take a new version of the VA to add more audio channels.
Cheers

Denny,

Do you know something I don't on the internal hardware specifications in the device that you can share?

This appears to be software related more than hardware. At present, in the software the device can dynamically switch between hdmi and aux for respective L/R, this then constructs the stream that is associated within the video. If both streams are accessible within the device, it may be viable from a software layer to abstract that into a separate audio layer, as per the atomos range.

What makes you think the device couldn't handle this? Cpu, memory, write throughout, hardware switching of audio components? Are the atomos range that much more powerful internally..?

At the time when I bought the VA, it seemed like a better choice than atomos, however the current range seem to be very sophisticated.

BM previously stated using both embedded audio and aux XLR audio mixed together or on separate tracks was not possible due to hardware limitations on the current model. My assumption is, the audio processor can only handle two channels, like the Hyperdeck Shuttle, and does not have internal mixing capabilities to mix both sources, due to audio processed limitations.

My only insight is 20+ years of experience in audio recording and audio solutions for video recording. An audio recordrecording need hardware support for multiple track recording, you can not get 4-tracks out of a recorder designed to support two tracks. To merge four channels of audio into two recorded tracks, requires some type of audio mixer processor to do this, an a means to control the level of each input, something the VA lacks.

The PixE has 6 to 8 tracks available, while the Atomos Shogun has 12 tracks available of embedded audio.

The VA was designedvas a simple, low vista monitor recorder, aimed primarily at the DSLR video market, and requests for external audio inputs on the original VA HD, resulted in the additional audio inputs on the newer VA4K.

Cheers

Thanks Denny, very much appreciate the context, it makes sense

For reference, here is a support log I had with Atomos regarding this, the answers derive at the same conclusions in this thread, adding for context value as it may provide some useful data to those who review this thread in the future :

James

Jul 19, 03:06 AEST

Is it possible to combine, audio coming in via HDMI and audio coming in via XLR on this device, so the stereo from the HDMI and stereo from the XLR becomes one audio?





Shahid Iqbal (ATOMOS)

Jul 19, 20:01 AEST

Hi James,

no unfortunately not.

Best wishes

Atomos GmbH





James

Jul 19, 20:02 AEST

Let me rephrase my question, is it possible, to capture both the HDMI
audio and the XLR audio, as seperate audio streams, retaining the L/R
audio for each channel?





Shahid Iqbal (ATOMOS)

Jul 19, 20:18 AEST
Hi James,

you can record HDMI embedded and and analogue Audio together.
But it will be Channel 172 and 3/4. The Analogue Audio will be moved to 1 and 2 channel and the HDMI embedded to 3 and 4

Best wishes

Atomos GmbH