Audio to Alexa Mini

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Stout Film
Posts: 55
Joined: Sat Dec 12, 2015 9:08 pm

The Alexa Mini is a great tool because you can use it in many different ways. It's obviously intended for gimbals and drones but it's small size makes it an (unexpected?) great doc camera for a lot of situations. The problem is getting audio (even scratch audio) into the camera. I like to use a sound-guy/girl and jam whenever possible but it's not always possible so I'm looking to share solutions back and forth with y'all.

INPUTS: I really wish the lemo input was mic-level; I think that would make the Remote Audio cable or the Wooden Camera A-box a solution (minus phantom power and a good way to adjust levels, of course). Right now I'm thinking the best solution would be to get a Sound Devices MixPre-D and mount it to the rods by your battery plate out the back, which could give you phantom power and give you line-level. It's too big for my tastes on the mini, but I can't think of a good smaller solution like this. I'd be very interested in some tiny little scratch audio mic that we could attach that is self powered and has line-level output. I don't think it exists; somebody please invent it!

MONITORING: There is no great way to monitor audio on the Mini. Again, I know this is not a priority for the concept but we are all going to find the best workarounds. I'm using a SmallHD 502, which has audio meters and also a headphone jack. There's a very slight delay. Obviously not super professional to be monitoring this way, but it is what it is.

Best thing would be if Arri had some way of making a great audio solution I/O box that could plug into that lemo port or wherever. People would pay handsomely for it.

Cheers everyone!
Christoph Gschloessl
Posts: 6
Joined: Tue Nov 24, 2015 11:13 am
Location: Munich, Germany

Hello and thank you for your feedback. We appreciate such feedback to improve our products.
I'll forward your comments to our ALEXA MINI product manager.

Best regards
Christoph Gschloessl
Digital Camera Service
Michael Jonas
Posts: 20
Joined: Thu Mar 26, 2015 3:28 pm

Hi,
thanks for your feedback!

The priority for the ALEXA Mini was the form factor and weight and the pcbs have been designed to be as compact as possible.

Initially we thought that we would not be able to support audio - until we found a spot on one of the boards that was able to fit just the audio codec. We decided it was worth giving it a try as a scratch track would be very valuable in some cases. It turned out to be good, so the quality is much better than a scratch track, but in order to access it we had to place the audio lemo in front.

Unfortunately we do not have any space on the pcbs to provide an amplifier, power regulation for phantom power or an audio output - and without that we won't be able to build an audio box with the functionality you requested.
eatChocolate
Posts: 2
Joined: Sun Mar 13, 2016 10:24 pm

Hey Stout Film,

We were getting really frustrated as well with this audio on the camera. The only solution we managed to find was to use the Beachtek DXA SLR ULTRA. Not the smallest solution, but it works great! We've contacted lots of manufacturers and nothing out there that will do the trick unfortunately.

BUT

Wait until NAB as I know a great solution will be announced then (and shipping straight away) which will solve all our problems with this silly non-phantom powered audio input ;)
Stout Film
Posts: 55
Joined: Sat Dec 12, 2015 9:08 pm

Thanks Everyone,
Yes totally makes sense to cut audio for form factor, now just hoping for good solutions to mount on camera. I wish there was a mic that just incorporated phantom and a pre-amp into it and went direct to the lemo on the front of camera so we could go straight in (but unlikely to get a solution like that. I picked up a used Sound Devices Mix Pre-D which works well but is big for most people's needs (very similar to the Beachtek DXA SLR ULTRA in previous post). Excited something will be released at NAB. If you back mount batteries, could be a good addition to the other side (operating blindly) to offset MVF-1 weight.
Here's another solution that I haven't tried yet, but the good guys at Gotham Sound recommended (will get the levels up, but won't be a real monitoring/mixing solution):
It's the Kortwich VCP-20 Pro, 3 items down on this page: http://www.filmtontechnik.de/en/product ... er-supply/
Looks nice and small. If anyone has tried it let us know.
Thanks!
ACSE GmbH
Posts: 5
Joined: Wed Apr 20, 2016 10:11 am

This is where we come into game:

We are a professional manufacturer from munich, currently dipping into high end camera equipment.
To this point we made quite some useful breakoutboxes
Image

As we are currently designing the newest member with high end preamps and levelling we would be eager to get involved with you all. Since we are building this for all of you guys and gals out there in the field working with it:

Which features should an audio addition have?
*this post was edited 63 times
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Robert from the ACSE Team
http://www.acse-gmbh.de
Stout Film
Posts: 55
Joined: Sat Dec 12, 2015 9:08 pm

ACSE GmbH wrote:This is where we come into game:
Which features should an audio addition have?
That's exciting, thanks!

High quality preamp with Line level out and cable that goes right into Mini (not XLR outs that we have to then adapt to lemo 5pin).
Dial for adjusting levels
As small as possible and mounts easily/quickly to the side brackets.
Mini (1/8") headphone jack.
Runs off external/d-tap (so it doesn't add bulk by having internal battery compartment)

Not sure if most people would rather have a super small/simple 1-input option or a bigger 2-input option. For me what would set it apart from what is already out there (I use the Sound Devices Mix Pre-D) is if it could be very small.

cheers
ACSE GmbH
Posts: 5
Joined: Wed Apr 20, 2016 10:11 am

That is exactly what we were thinking, great to see we are heading in the right direction!
*this post was edited 63 times
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Robert from the ACSE Team
http://www.acse-gmbh.de
ACSE GmbH
Posts: 5
Joined: Wed Apr 20, 2016 10:11 am

Stout Film wrote: As small as possible and mounts easily/quickly to the side brackets.
So, it would be "enough" to have a 1/4" Screw mounting option, or am i am wrong?
We also would have the arri rosette as an option, but that doesnt seem to be the right versatile thing to mount on for this.
*this post was edited 63 times
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Robert from the ACSE Team
http://www.acse-gmbh.de
Stout Film
Posts: 55
Joined: Sat Dec 12, 2015 9:08 pm

yes, i believe 1/4-20 would be strong enough.
i wouldn't use the rosette, because that's often occupied by a handle.
amirpohan
Posts: 6
Joined: Thu Apr 21, 2016 2:56 pm

ACSE GmbH wrote:This is where we come into game:

We are a professional manufacturer from munich, currently dipping into high end camera equipment.
To this point we made quite some useful breakoutboxes
Image

As we are currently designing the newest member with high end preamps and levelling we would be eager to get involved with you all. Since we are building this for all of you guys and gals out there in the field working with it:

Which features should an audio addition have?

i'd buy this! when do you guys think you will be able to start selling it?
ACSE GmbH
Posts: 5
Joined: Wed Apr 20, 2016 10:11 am

Great to hear!

It is quite hard to give you a exact date, but we will need 3-5 months for the whole design.
*this post was edited 63 times
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Robert from the ACSE Team
http://www.acse-gmbh.de
Patrick Tresch
Posts: 1
Joined: Tue Sep 20, 2016 3:58 pm

Is there a way to access the AES audio of the camera. This would skip the A/D/A/D process. I know a manufacturer that have a small audio preamp with AES output. This would be the best solution for pristine sound.

Thanks

Patrick
TPCoughlan
Posts: 2
Joined: Tue Sep 20, 2016 5:12 pm

I made a pre-amp for the Alexa Mini earlier this year using an RDL STM-2: http://www.rdlnet.com/product.php?page=64 inside of an Altoids tin.

The basics:

-requires 24vdc to power (arri rs 3-pin Fischer) which will also necessitate the use of an aftermarket battery plate like the Wooden Camera D-Box as there is no 24v accessory out of the camera
-mono mic output terminates to a TA3 male connector
-output level can be adjusted by 25-turn pot which i’ve parked in the middle; from there the camera can increase or decrease the level as needed
-outputs to both channels 1 & 2
-audio monitoring must be done via sdi monitoring preferably with a headphone output; again, thanks arri

I'll admit it's a little crude but most of our clients are using the Minis in MOS applications and it's worked for those needing mic input in more doc. situations
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Elliott Balsley
Posts: 22
Joined: Mon Jan 18, 2016 8:39 pm

I built headphone amps in Altoids tins when I was a kid. It's funny to see it being used with a professional camera like this! :D
eatChocolate
Posts: 2
Joined: Sun Mar 13, 2016 10:24 pm

If anyone is reading this looking for an audio solution, Beachtek released this solution for Alexa Mini:

http://cvp.com/index.php?t=product/beac ... alexa_mini
Stout Film
Posts: 55
Joined: Sat Dec 12, 2015 9:08 pm

eatChocolate wrote:If anyone is reading this looking for an audio solution, Beachtek released this solution for Alexa Mini:

http://cvp.com/index.php?t=product/beac ... alexa_mini

Does anyone see the major advantage of this over a Mix Pre-D? I've been hoping something smaller would come out. thx
Beachtek
Posts: 3
Joined: Wed Feb 17, 2016 8:35 am

I am happy to announce that we now have an audio solution for the Arri Alexa Mini. Our DXA-ALEXA preamplifier provides two transformer balanced XLR inputs with phantom power and a 40 or 60 dB gain stage along with headphone monitoring. It is designed to be as compact as possible to accommodate the Neutrik XLR inputs and outputs along with the switches and controls. A lot of thought went into this design to make it fit into a typical Arri rig including carbon fiber construction for light weight and water resistant toggle switches to be used under any conditions.

I will be happy to answer any specific questions you may have about the DXA-ALEXA.

http://beachtek.com/dxa-alexa/

Harry Kaufmann
Product Support
Beachtek
Stout Film
Posts: 55
Joined: Sat Dec 12, 2015 9:08 pm

Beachtek wrote:I am happy to announce that we now have an audio solution for the Arri Alexa Mini. Our DXA-ALEXA preamplifier provides two transformer balanced XLR inputs with phantom power and a 40 or 60 dB gain stage along with headphone monitoring. It is designed to be as compact as possible to accommodate the Neutrik XLR inputs and outputs along with the switches and controls. A lot of thought went into this design to make it fit into a typical Arri rig including carbon fiber construction for light weight and water resistant toggle switches to be used under any conditions.

I will be happy to answer any specific questions you may have about the DXA-ALEXA.

http://beachtek.com/dxa-alexa/

Harry Kaufmann
Product Support
Beachtek

-----------
Thanks Harry! 2 questions for you. How do we get a RTN to your mixer from the camera for monitoring? I see an input for this but don't see a way on the Mini besides going from certain external monitors with a headphone jack. And have you considered making one that is half the size with just one simple input. Many of us just want a simple small-as-possible option with one input. And it would be great if it came with a cable to attach to the camera.. Thanks!
Beachtek
Posts: 3
Joined: Wed Feb 17, 2016 8:35 am

Yes, you are correct, there is no audio out from the camera except via some external monitors with a headphone jack. The RTN feature was included on the DXA-ALEXA for use in this scenario or when used with other cameras like the RED.

We do have a much smaller device that has only one XLR input plus three mini-jack inputs for 3.5mm mics such as the popular Rode VideoMic, or wireless systems. Please see our DXA-MICRO PRO page for more information.

It only provides 30dB of gain as compared to the 60dB of gain on the DXA-ALEXA but you can simply increase the camera gain to compensate. AbleCine in New York tested this setup and it works very well.

The 5 pin Lemo connector that attaches to the ALEXA Mini is very expensive and it not required when using the DXA-ALEXA on other cameras like the RED which is why we did not include it - the cost would have simply been added to the price of the preamp.
Stout Film
Posts: 55
Joined: Sat Dec 12, 2015 9:08 pm

Hi everyone,
What are your normal gain settings when inputting audio from a mixer? I know this depends on a lot of factors, but say typical interview mic'ing from a MixPre or similar.... I'm generally having to push my in-camera levels up in the teens, like +12 to +18. On a similar setup but going straight into the Amira without a separate mixer, I'm at like +5 and get much cleaner audio.
Curious if anyone using something like a MixPre-D could share their settings start to finish.
I'm also curious about trying this Beachtek out at some point.

Also Arri, are you aware that in the current SUP you cannot use wifi to input a number higher than 9 (no two digit numbers). You have to use the MVF-1 to do this. I mentioned this months ago but it's the same in more recent SUP's.

Cheers!
Jan Heugel
Posts: 516
Joined: Wed Aug 13, 2014 3:15 pm
Location: Munich, Germany
Contact:

Hey Stout,
to enter a double digit number place the cursor in front of the first digit (even if this is zero), then enter e.g. 12 and confirm.

Best,
Jan
Jan Heugel
Application Engineer
Stout Film
Posts: 55
Joined: Sat Dec 12, 2015 9:08 pm

Jan Heugel wrote:Hey Stout,
to enter a double digit number place the cursor in front of the first digit (even if this is zero), then enter e.g. 12 and confirm.

Best,
Jan

Thanks Jan but I've tried this many times and it doesn't work for me, at least on my iphone which is all I've tried for wifi. I go all the way to the left with the cursor and it if, for example "12" is the goal, it will only accept "1". It works perfectly on the MVF-1 by this same method so that's what I use.
justin lovell
Posts: 15
Joined: Tue Dec 22, 2015 5:19 am

We're using a mini audio lemo cable to male 3.5mm jack. Plugged into a Zoom h1 recorder. This can be used for scratch audio using it's mic.

Otherwise we can use the wooden camera abox and take a feed from sound guy.
OR
Use the mini audio lemo cable to male 3.5mm jack - convert this to XLR or female 3.5mm and take a feed from a wireless mic hop.

Hope that helps!

Justin Lovell
Associate CSC
www.justinlovell.com

Frame Discreet
8/16/35 film scans
www.framediscreet.com
Justin Lovell
Associate CSC Cinematographer

Frame Discreet // 8/16/35 film scans
http://www.framediscreet.com
Stout Film
Posts: 55
Joined: Sat Dec 12, 2015 9:08 pm

justin lovell wrote:We're using a mini audio lemo cable to male 3.5mm jack. Plugged into a Zoom h1 recorder. This can be used for scratch audio using it's mic.
Thanks Justin! This is an interesting option, I never knew the Zoom H1 had a line level output. This could be the simples and lightest solution for scratch audio. Curious if adding a Sennheiser MKE 400 to it could get better or more directional audio in a pinch. 2 questions for you:

1) Where are you getting your AlexaMini Lemo to 3.5mm cable? Looks like Remote Audio makes something for $199 and theres a cheaper version for $49: https://www.amazon.com/Right-Angle-3-5m ... mini+cable

2) What do you find your are setting your in camera audio gain to? Though I know it's just for scratch, I'm curious if I can get something useable for a doc situation in a pinch.
Laurie Webb
Posts: 1
Joined: Sat Feb 04, 2017 10:09 pm

Hi. My name is Laurie with Mozegear. We have a new tiny microphone pre-amp designed for the Alexa Mini. It is called the “Mini Papi” and it has some of the features which we think will address your “wish list”.

*Tiny size - It is only 4.2 cubic inches (2.5” x 2.1” x 0.8”) and just 4 oz

*Clean high-end audio quality that can be used for primary sound or a scratch track

*Additional features that support audio quality include 2 limiters to reduce clipping. Adjustable High Pass Filter to control wind noise. Switchable output levels and a bracket channel to help avoid clipping in the camera.

*There is a level (gain) control that has plenty of headroom (72dB of gain with 65 dB range.) It is adjustable in 5 db steps.

*Externally powered (via 2 pin Lemo) with an isolated power supply to reduce hum loops. Alternative powering via a micro usb.

*48-volt phantom power

For those who haven’t heard about our company "Mozegear", we manufacture equipment for production sound. We are located in Irvine, California and our products are made and serviced in the USA. We also have a second service center in London.

We are currently shipping. Please note that there are two versions of the Mini Papi, 1.) Alexa Mini/Camera version 2.) Audio Engineer version. Make sure you ask for the Alexa Mini or camera version.

For more information: http://www.mozegear.com
Or you can shoot me an email at: lauriew@mozegear.com
Stout Film
Posts: 55
Joined: Sat Dec 12, 2015 9:08 pm

Thanks Laurie,
I'm glad a company has stepped up. I think a lot of people will want one. I'll be ordering one today. Thanks!
FergusH
Posts: 3
Joined: Wed Feb 14, 2018 8:10 am

This thread is several years old now but still very useful. I’ve got a MixPre-3 that I’m using on a Alexa Mini but I’m thinking about getting a Mini Papi.

Does anyone have other suggestions of products I should look at? This is for production audio, not just scratch audio. Basically it’s for using the Alexa Mini in situations where the Amira would probably be a better choice! ;-)

Thanks.
rizarefaldi
Posts: 2
Joined: Sat May 01, 2021 8:09 pm

Is there a way to access the AES audio of the camera. This would skip the A/D/A/D process.
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