Pocket 4K - weak preamps?

The place for questions about shooting with Blackmagic Cameras.
  • Author
  • Message
Offline
User avatar

Rakesh Malik

  • Posts: 3236
  • Joined: Fri Dec 07, 2012 1:01 am
  • Location: Vancouver, BC

Re: Pocket 4K - weak preamps?

PostTue Nov 27, 2018 7:53 pm

Australian Image wrote:Then why does my Olympus E-M1 MkII provide me with the option of turning on power to the 3.5mm mic input? If it's off, the mic doesn't work, if on, it does.


It's plug-in power, not phantom power -- different spec, and appropriate that it's available on a consumer camera, but not on a professional one.
Rakesh Malik
Cinematographer, photographer, adventurer, martial artist
http://WinterLight.studio
System:
Asus Flow X13, Octacore Zen3/32GB + XG Mobile nVidia RTX 3080/16GB
Apple M1 Mini/16GB
Offline

John Paines

  • Posts: 5787
  • Joined: Tue Jul 28, 2015 4:04 pm

Re: Pocket 4K - weak preamps?

PostTue Nov 27, 2018 8:03 pm

rick.lang wrote:No wonder BMD has commented on better control of noise... they just forgot to mention they crushed the levels to do it. (I may be guilty of overstating it.)


Unless the camera mics are extraordinarily hot, it's hard to draw that conclusion. The onboard sound is good (for a camera, anyway), and the levels are in the range of normal.

I think the 3.5mm issue is a manufacturing defect, but I guess we'll find out. BTW, it's only fair to note that Robert N. came up with pretty much the same measurement for mic level a few weeks ago.
Offline

John Morris

  • Posts: 199
  • Joined: Mon Jul 31, 2017 12:44 am
  • Location: Melbourne

Re: Pocket 4K - weak preamps?

PostTue Nov 27, 2018 10:52 pm

John Paines wrote: Just to clarify, was it your finding that 3.5mm line level stereo is also 12db less sensitive than line level on the BMPCC?

Yes, thats right, at least on my copy. I also thought initially the difference was greater, but that turned out to be inaccurate meters on the old BMPCC.
NVIDIA GTX1070 8GB
NVIDIA driver version 430.50
DeckLink Mini Monitor 4K
32G system memory
Resolve Studio 16.1.1.005 1 GPU
Linux Mint 19.2
Offline

Wayne Steven

  • Posts: 3362
  • Joined: Thu Aug 01, 2013 3:58 am
  • Location: Earth

Re: Pocket 4K - weak preamps?

PostWed Nov 28, 2018 4:52 am

Its probably hard to tell from just a 1khz tone. The response curve and quality can vary on frequency and power. So it's probably worth testing at many frequency points varying power points and a general sweep to pick up any distortion missed, if you think something is a bit off. Is rightmark audio analyzer suitable for this, or has things moved on from those days?

The higher sensitivity in mono is probably because the sample is going to one ADC, but you wouldn't think it as its only taking one microphone (I hope). Maybe there is some non linear response there?

But, isn't it normal professionally to record lower db to handle highs for a wider dynamic range, as more sensitive equipment will pickup the lower end of the range?
aIf you are not truthfully progressive, maybe you shouldn't say anything
bTruthful side topics in-line with or related to, the discussion accepted
cOften people deceive themselves so much they do not understand, even when the truth is explained to them
Offline
User avatar

rick.lang

  • Posts: 17175
  • Joined: Wed Aug 22, 2012 5:41 pm
  • Location: Victoria BC Canada

Re: Pocket 4K - weak preamps?

PostWed Nov 28, 2018 7:01 am

Thanks John Paines for the reminder re Robert’s post.


Sent from my iPhone using Tapatalk
Rick Lang
Offline

Richard Knight

  • Posts: 163
  • Joined: Mon Dec 17, 2012 1:39 pm

Re: Pocket 4K - weak preamps?

PostWed Nov 28, 2018 1:41 pm

Most tv broadcast dialogue in the UK is recorded at about -20 to -12, perhaps the mic amps are optimised for this level?
Offline

Leon Benzakein

  • Posts: 1375
  • Joined: Thu Aug 15, 2013 3:40 pm

Re: Pocket 4K - weak preamps?

PostWed Nov 28, 2018 2:57 pm

Ray, may I put forward the idea that you are experiencing a problem on your particular camera re the Rode VideoMicro and plug-in power.

I have the original BMPCC and my Rode VideoMicro works as it should, although at low level.
I do not see why BMD would not include this function on the new BMPCC4K.
Others have stated that plug-in power works on their BMPCC4k.

It could just be your camera.

I have a Beachtek mini mixer specificly made for the BMPCC that does not provide plug-in power, so I understand your frustration.
Television: Lighting/Cameraman, O.B. Camera Operator, Experience in EFP, EPG and ENG , Grip, Lamp Operator
Film: Grip, Lamp Operator
Theater: Lighting Designer, Light board Operator, Stage Electrician, Stage Management
Offline

Leon Benzakein

  • Posts: 1375
  • Joined: Thu Aug 15, 2013 3:40 pm

Re: Pocket 4K - weak preamps?

PostWed Nov 28, 2018 3:29 pm

Denny Smith wrote:John Paines, I will not bother you anymore with my thoughts or ideas. It is comments like yours that have forced the most of the original contributors off this forum. Good bye.


Denny, I for one appreciate your thoughts and ideas. Please keep them coming.
No one is perfect and you have proved that you are the first one to admit this.
What I appreciate most about your posts are the spelling mistakes.
This flaw gives me a feeling of superiority because I am aware of how smart you really are but how really dumb your iPad is and yet you won't fire the thing.
At least my keyboard is smarter than yours.

I do not understand why people have to be unpleasant.

Plug-in power to the people!
Television: Lighting/Cameraman, O.B. Camera Operator, Experience in EFP, EPG and ENG , Grip, Lamp Operator
Film: Grip, Lamp Operator
Theater: Lighting Designer, Light board Operator, Stage Electrician, Stage Management
Offline
User avatar

joe12south

  • Posts: 782
  • Joined: Tue Jan 16, 2018 4:14 pm
  • Location: Nashville, TN
  • Real Name: Joseph Moore

Re: Pocket 4K - weak preamps?

PostWed Nov 28, 2018 3:56 pm

There are two camps on xlr performance (some reports of fine and dandy, others complaining of the same issue as with 3.5mm), so it will be interesting to see what your findings are, at least for your own unit.

I'm interested, as well, but there is no doubt that the P4K's XLR inputs are weak. Compared to every other device I own, the signal is demonstrably lower - unusable with anything but a "hot" mic.

Just as an example, with the P4K's gain maxed, it records a lower signal level than the GH5 at minimum.

While it's possible this is just my camera, how likely is that, really?
Dedicated curmudgeon. Part-time artiste.
Offline

Johan Cramer

  • Posts: 245
  • Joined: Mon Aug 26, 2013 3:33 pm

Re: Pocket 4K - weak preamps?

PostWed Nov 28, 2018 5:04 pm

To be clear, the Pocket 4K does have plug-in power on its 3.5mm jack, otherwise mics such as the Ohrwurm binaural mic or the Rode VideoMicro wouldn't work at all.

With Ohrwurm's creator, Wolfgang Winne of digitalfx, I tested whether the plug-in power of the camera might be too weak. Wolfgang provided me with an independent, 9V block battery-powered plugin-power source that could be put in between the camera and the mic. Unfortunately, it didn't change audio levels on the camera at all.

His conclusion (translated from German): "the camera's audio-in must have very low impedance..... that's likely the problem, the camera input strains the microphone too much (almost to the point of short circuiting)."

Unlike Wolfgang, I'm not an engineer, so maybe others can think up solutions.
Offline

Denny Smith

  • Posts: 13131
  • Joined: Thu Aug 01, 2013 4:19 pm
  • Location: USA, Northern Calif.

Re: Pocket 4K - weak preamps?

PostWed Nov 28, 2018 7:16 pm

Ray, I think you should contact your local,BM Support Office and RMA that Camera! Obviously something is wrong there, you need to have the camera tested.
Cheers
Denny Smith
SHA Productions
Offline

Denny Smith

  • Posts: 13131
  • Joined: Thu Aug 01, 2013 4:19 pm
  • Location: USA, Northern Calif.

Re: Pocket 4K - weak preamps?

PostWed Nov 28, 2018 7:18 pm

Leon, thanks. I did fire my old Mini IPad, sent it to my daughter. I do have a Apple Bluetooth keyboard for my IPadPro, which I have not been using, so I guess it is time to break it out... :roll:
Cheers
Denny Smith
SHA Productions
Offline

b_flow

  • Posts: 4
  • Joined: Tue Nov 20, 2018 3:30 am
  • Real Name: Brian Flowers

Re: Pocket 4K - weak preamps?

PostWed Nov 28, 2018 7:39 pm

has anyone actually RMA'd this camera for the audio issues? Has anyone gotten it fixed?
Offline

Leon Benzakein

  • Posts: 1375
  • Joined: Thu Aug 15, 2013 3:40 pm

Re: Pocket 4K - weak preamps?

PostWed Nov 28, 2018 9:00 pm

Johan Cramer wrote:Wolfgang provided me with an independent, 9V block battery-powered plugin-power source that could be put in between the camera and the mic.


Can you provide info on this 9V block battery-powered plugin-power source that can be put in between the camera and the mic.

I have been using a Zoom H1 as power source for the Rode VideoMicro when using the Beachtek device that does not supply plug-in power even though it has a 9 volt battery. What were they thinking?
Television: Lighting/Cameraman, O.B. Camera Operator, Experience in EFP, EPG and ENG , Grip, Lamp Operator
Film: Grip, Lamp Operator
Theater: Lighting Designer, Light board Operator, Stage Electrician, Stage Management
Offline

John Paines

  • Posts: 5787
  • Joined: Tue Jul 28, 2015 4:04 pm

Re: Pocket 4K - weak preamps?

PostWed Nov 28, 2018 9:14 pm

[information pending, ignore.]
Last edited by John Paines on Wed Nov 28, 2018 9:38 pm, edited 1 time in total.
Offline

Johan Cramer

  • Posts: 245
  • Joined: Mon Aug 26, 2013 3:33 pm

Re: Pocket 4K - weak preamps?

PostWed Nov 28, 2018 9:26 pm

Leon Benzakein wrote:Can you provide info on this 9V block battery-powered plugin-power source that can be put in between the camera and the mic.

Wolfgang soldered/glued it as a quick-and-dirty, one-off test protoype and mailed it to me. It's the contraption on the left half of the image:

Image
Offline

Leon Benzakein

  • Posts: 1375
  • Joined: Thu Aug 15, 2013 3:40 pm

Re: Pocket 4K - weak preamps?

PostWed Nov 28, 2018 10:45 pm

Johan Cramer wrote:
Leon Benzakein wrote:Can you provide info on this 9V block battery-powered plugin-power source that can be put in between the camera and the mic.

Wolfgang soldered/glued it as a quick-and-dirty, one-off test protoype and mailed it to me. It's the contraption on the left half of the image:

Image


Thanks for the response but I was not able to access the image.
Cheers
Television: Lighting/Cameraman, O.B. Camera Operator, Experience in EFP, EPG and ENG , Grip, Lamp Operator
Film: Grip, Lamp Operator
Theater: Lighting Designer, Light board Operator, Stage Electrician, Stage Management
Offline

Leon Benzakein

  • Posts: 1375
  • Joined: Thu Aug 15, 2013 3:40 pm

Re: Pocket 4K - weak preamps?

PostWed Nov 28, 2018 11:03 pm

I wonder if this would work.

3.5mm MONO JACK PLUG IN POWER SUPPLY BATTERY MODULE FOR ELECTRET LAPEL LAVALIERE

https://www.ebay.com/itm/3-5mm-MONO-JAC ... .l4275.c10

US $17.55

power supply for lavalier mic.jpg
power supply for lavalier mic.jpg (118.57 KiB) Viewed 16610 times
Television: Lighting/Cameraman, O.B. Camera Operator, Experience in EFP, EPG and ENG , Grip, Lamp Operator
Film: Grip, Lamp Operator
Theater: Lighting Designer, Light board Operator, Stage Electrician, Stage Management
Offline

Leon Benzakein

  • Posts: 1375
  • Joined: Thu Aug 15, 2013 3:40 pm

Re: Pocket 4K - weak preamps?

PostWed Nov 28, 2018 11:18 pm

I found this by Aputure and wondered if the inline PSU would power the VideoMicro.

US$30.00-$35.00

https://www.aputure.com/products/a-lav-1

Aputure lavaliere mic.jpg
Aputure lavaliere mic.jpg (49.21 KiB) Viewed 16605 times


Only downside is rechargeable battery.
Television: Lighting/Cameraman, O.B. Camera Operator, Experience in EFP, EPG and ENG , Grip, Lamp Operator
Film: Grip, Lamp Operator
Theater: Lighting Designer, Light board Operator, Stage Electrician, Stage Management
Offline

RobStowell

  • Posts: 86
  • Joined: Mon Nov 21, 2016 10:27 pm

Re: Pocket 4K - weak preamps?

PostThu Nov 29, 2018 9:14 am

Again - there is definitely power through the 3.5mm jack unless the camera has a fault. But the level you can get is so low there might as well not be :( At least it will run radio mics.
Just got the mini xlr adapters. Hope that isn't also very low. I'd like to use the cam for interviews without an extra preamp to worry about.
Offline

Wayne Steven

  • Posts: 3362
  • Joined: Thu Aug 01, 2013 3:58 am
  • Location: Earth

Re: Pocket 4K - weak preamps?

PostThu Nov 29, 2018 2:28 pm

Richard Knight wrote:Most tv broadcast dialogue in the UK is recorded at about -20 to -12, perhaps the mic amps are optimised for this level?


My point.
aIf you are not truthfully progressive, maybe you shouldn't say anything
bTruthful side topics in-line with or related to, the discussion accepted
cOften people deceive themselves so much they do not understand, even when the truth is explained to them
Offline

Wayne Steven

  • Posts: 3362
  • Joined: Thu Aug 01, 2013 3:58 am
  • Location: Earth

Re: Pocket 4K - weak preamps?

PostThu Nov 29, 2018 2:31 pm

Johan Cramer wrote:To be clear, the Pocket 4K does have plug-in power on its 3.5mm jack, otherwise mics such as the Ohrwurm binaural mic or the Rode VideoMicro wouldn't work at all.

With Ohrwurm's creator, Wolfgang Winne of digitalfx, I tested whether the plug-in power of the camera might be too weak. Wolfgang provided me with an independent, 9V block battery-powered plugin-power source that could be put in between the camera and the mic. Unfortunately, it didn't change audio levels on the camera at all.

His conclusion (translated from German): "the camera's audio-in must have very low impedance..... that's likely the problem, the camera input strains the microphone too much (almost to the point of short circuiting)."

Unlike Wolfgang, I'm not an engineer, so maybe others can think up solutions.



I remember Wolfgang, how's he doing? He's a thorough fellow. What was his website again?
aIf you are not truthfully progressive, maybe you shouldn't say anything
bTruthful side topics in-line with or related to, the discussion accepted
cOften people deceive themselves so much they do not understand, even when the truth is explained to them
Offline

Johan Cramer

  • Posts: 245
  • Joined: Mon Aug 26, 2013 3:33 pm

Re: Pocket 4K - weak preamps?

PostThu Nov 29, 2018 2:52 pm

Wayne Steven wrote:I remember Wolfgang, how's he doing? He's a thorough fellow. What was his website again?

http://www.ohrwurmaudio.eu
Offline

Leon Benzakein

  • Posts: 1375
  • Joined: Thu Aug 15, 2013 3:40 pm

Re: Pocket 4K - weak preamps?

PostThu Nov 29, 2018 4:09 pm

Australian Image wrote:
I'm fairly certain that would work and I considerer it, but was put off by the very long cable.

But what you need to consider is that they don't amplify the sound.


This may be what you are looking for:

Saramonic SmartRig+ 2-Channel XLR Microphone Audio Mixer

https://www.bhphotovideo.com/c/product/ ... tml?sts=pi

https://www.amazon.com/s/ref=nb_sb_noss ... c+SmartRig

Television: Lighting/Cameraman, O.B. Camera Operator, Experience in EFP, EPG and ENG , Grip, Lamp Operator
Film: Grip, Lamp Operator
Theater: Lighting Designer, Light board Operator, Stage Electrician, Stage Management
Offline

John Paines

  • Posts: 5787
  • Joined: Tue Jul 28, 2015 4:04 pm

Re: Pocket 4K - weak preamps?

PostThu Nov 29, 2018 4:24 pm

b_flow wrote:has anyone actually RMA'd this camera for the audio issues? Has anyone gotten it fixed?


BMD support is aware of the issue and it may be worth filing a report, so the scope of the condition becomes clearer to them, but I wouldn't send in a camera at present, as it's unlikely that whatever comes back will be better, pending further developments....

I think it's fair to say the camera was not designed this way to serve the British TV market.
Offline
User avatar

rick.lang

  • Posts: 17175
  • Joined: Wed Aug 22, 2012 5:41 pm
  • Location: Victoria BC Canada

Re: Pocket 4K - weak preamps?

PostThu Nov 29, 2018 6:57 pm

Leon, that Saramonic SmartRig+ is impressive for the price. May not include any limiter though.


Sent from my iPhone using Tapatalk
Rick Lang
Offline

Leon Benzakein

  • Posts: 1375
  • Joined: Thu Aug 15, 2013 3:40 pm

Re: Pocket 4K - weak preamps?

PostThu Nov 29, 2018 11:36 pm

rick.lang wrote:Leon, that Saramonic SmartRig+ is impressive for the price. May not include any limiter though.


Sent from my iPhone using Tapatalk


"Word!"
Television: Lighting/Cameraman, O.B. Camera Operator, Experience in EFP, EPG and ENG , Grip, Lamp Operator
Film: Grip, Lamp Operator
Theater: Lighting Designer, Light board Operator, Stage Electrician, Stage Management
Offline

Leon Benzakein

  • Posts: 1375
  • Joined: Thu Aug 15, 2013 3:40 pm

Re: Pocket 4K - weak preamps?

PostFri Nov 30, 2018 12:37 am

Australian Image wrote:My audio is now excellent, through just a Rode VideoMicro. Some morning tests today picked up even faint bird songs in the distance.


What did you do different?
Television: Lighting/Cameraman, O.B. Camera Operator, Experience in EFP, EPG and ENG , Grip, Lamp Operator
Film: Grip, Lamp Operator
Theater: Lighting Designer, Light board Operator, Stage Electrician, Stage Management
Offline

Wayne Steven

  • Posts: 3362
  • Joined: Thu Aug 01, 2013 3:58 am
  • Location: Earth

Re: Pocket 4K - weak preamps?

PostFri Nov 30, 2018 12:46 am

John Paines wrote: I think it's fair to say the camera was not designed this way to serve the British TV market.


I'm curious about the design reason behind the low recordings in the UK. I know it is used professionally, not just there, and a bane on end consumer releases where you just can't get the volume on smaller systems.

Is it just to squash the lower end to make more room for the higher end? I notice (just from memory nor observation) British TV productions seem to be more squashed and clean in the lower end. Of course that's not want you want out in the field live in documentaries, where you strain to dictate levels.

Here's a Bluetooth suggestion, a wheel control that let's you ride the audio live. You could pin it to a cage, or stick it on the side of the camera.
aIf you are not truthfully progressive, maybe you shouldn't say anything
bTruthful side topics in-line with or related to, the discussion accepted
cOften people deceive themselves so much they do not understand, even when the truth is explained to them
Offline

Wayne Steven

  • Posts: 3362
  • Joined: Thu Aug 01, 2013 3:58 am
  • Location: Earth

Re: Pocket 4K - weak preamps?

PostFri Nov 30, 2018 12:48 am

He put this powered section inbetween the mic and an amp:

Australian Image wrote:I've ordered one of these: https://audio-technica.com.au/products/at9903/ so I can to put the power module between my Rode VideoMicro and Cayin amplifier to provide power to the Rode. This, I hope, will enable me to get rid of the LS-14 audio recorder.
Last edited by Wayne Steven on Fri Nov 30, 2018 12:51 am, edited 1 time in total.
aIf you are not truthfully progressive, maybe you shouldn't say anything
bTruthful side topics in-line with or related to, the discussion accepted
cOften people deceive themselves so much they do not understand, even when the truth is explained to them
Offline
User avatar

rick.lang

  • Posts: 17175
  • Joined: Wed Aug 22, 2012 5:41 pm
  • Location: Victoria BC Canada

Re: Pocket 4K - weak preamps?

PostFri Nov 30, 2018 3:00 am

I think we’re just holding our breath to hear from BMD on this. If there’s nothing planned from BMD, you’ll certainly generate interest. Good news you have a solution today.


Sent from my iPhone using Tapatalk
Rick Lang
Offline

Leon Benzakein

  • Posts: 1375
  • Joined: Thu Aug 15, 2013 3:40 pm

Re: Pocket 4K - weak preamps?

PostSat Dec 01, 2018 10:33 pm

Australian Image wrote:
Leon Benzakein wrote:
Australian Image wrote:My audio is now excellent, through just a Rode VideoMicro. Some morning tests today picked up even faint bird songs in the distance.


What did you do different?


I detailed this in a previous post, but received no interest.


Huh :?: :?: :?: :?: :?:

I thought that asking questions was showing interest.
Television: Lighting/Cameraman, O.B. Camera Operator, Experience in EFP, EPG and ENG , Grip, Lamp Operator
Film: Grip, Lamp Operator
Theater: Lighting Designer, Light board Operator, Stage Electrician, Stage Management
Offline

Wayne Steven

  • Posts: 3362
  • Joined: Thu Aug 01, 2013 3:58 am
  • Location: Earth

Re: Pocket 4K - weak preamps?

PostSun Dec 02, 2018 9:44 am

I quoted it before for you Leon.
aIf you are not truthfully progressive, maybe you shouldn't say anything
bTruthful side topics in-line with or related to, the discussion accepted
cOften people deceive themselves so much they do not understand, even when the truth is explained to them
Offline

Leon Benzakein

  • Posts: 1375
  • Joined: Thu Aug 15, 2013 3:40 pm

Re: Pocket 4K - weak preamps?

PostSun Dec 02, 2018 4:03 pm

Wayne Steven wrote:I quoted it before for you Leon.


Thanks Wayne. I appreciate that.

I must have been on Mars with my buddy Matt Damon when Ray informed us that he had received the part he was waiting for.

My bad.

Are all Australians bad tempered or just the ones that purchase BMD products?
Television: Lighting/Cameraman, O.B. Camera Operator, Experience in EFP, EPG and ENG , Grip, Lamp Operator
Film: Grip, Lamp Operator
Theater: Lighting Designer, Light board Operator, Stage Electrician, Stage Management
Offline

Denny Smith

  • Posts: 13131
  • Joined: Thu Aug 01, 2013 4:19 pm
  • Location: USA, Northern Calif.

Re: Pocket 4K - weak preamps?

PostSun Dec 02, 2018 6:47 pm

[quote="Leon Benzakein”

Are all Australians bad tempered or just the ones that purchase BMD products?[/quote]

That is a good one Leon :lol:
Cheers
Denny Smith
SHA Productions
Offline

Wayne Steven

  • Posts: 3362
  • Joined: Thu Aug 01, 2013 3:58 am
  • Location: Earth

Re: Pocket 4K - weak preamps?

PostMon Dec 03, 2018 9:20 am

Leon Benzakein wrote:
Wayne Steven wrote:I quoted it before for you Leon.


Thanks Wayne. I appreciate that.

I must have been on Mars with my buddy Matt Damon when Ray informed us that he had received the part he was waiting for.

My bad.

Are all Australians bad tempered or just the ones that purchase BMD products?


Don't know, but find a lot of bad tempered non Australians on cinema forums.

I tend to find low end people a bit moodier around here and higher end people more wonderful on forums, but then again, non left wing Australians tend to not suffer foolishness gladly (except themselves). So, repeatedly asking about something posted and pointed out might fall in that category with them It doesn't really affect me that much, just a misunderstanding unless it refuses to resolve. Certain Europeans are the worst as far as attitude, worse then certain Americans. Australians tend to let things fly more than I do (because I SEE), but rough necks are rough necks, which gets me into Australian builders.

But still, I did require a logical leap to ascertain the reason why the video mic started working by itself, was because he inserted the part he had received previously to do it, between the camera and it. Still, good news. But BM should publish a microphone sticky with which mokrs work with it.


Hmm, just a thought I want to do my own processor array, and BM does enough products to run an volume asic wafer program with a mixture of parts on the wafer, allowing them to custom asic all their cameras reducing cost, size and heat. I could hitch a ride. They can do this where it is maybe more expensive for Red (though they may have arrangements with their sensor provider) because BM produces a range of products making their volumes much higher). Maybe I should talk with them in the future my designs would outdo most anything they are using. Got to dig up that asic chip making software out they used for industry leading low energy solutions.
aIf you are not truthfully progressive, maybe you shouldn't say anything
bTruthful side topics in-line with or related to, the discussion accepted
cOften people deceive themselves so much they do not understand, even when the truth is explained to them
Offline

Benjamin de Menil

  • Posts: 330
  • Joined: Wed Feb 04, 2015 9:04 pm

Re: Pocket 4K - weak preamps?

PostTue Dec 04, 2018 6:52 pm

I just tried out the stereo videomic X with the pocket 4K's 3.5mm jack. With the mic seto to +20db mode, levels barely showed when I clapped right in front of the mic.

Also, the pocket 4k's mic gain is grayed out when I have inputs set to 3.5mm. Is this normal?
Offline

Benjamin de Menil

  • Posts: 330
  • Joined: Wed Feb 04, 2015 9:04 pm

Re: Pocket 4K - weak preamps?

PostTue Dec 04, 2018 7:30 pm

Benjamin de Menil wrote:I just tried out the stereo videomic X with the pocket 4K's 3.5mm jack. With the mic seto to +20db mode, levels barely showed when I clapped right in front of the mic.

Also, the pocket 4k's mic gain is grayed out when I have inputs set to 3.5mm. Is this normal?


I just got of the phone with BM support and discovered something that may be helpful to people using 3.5mm inputs:
The 3.5mm inputs can be set to line level or mic level. But the mic level option is not available in the menu if one of the channels is set to 3.5mm line. So before setting the first side to 3.5mm mic, make sure the other side isn't set to one of the 3.5mm line options. The reverse is true for discovering line level options if you have a side set to mic level.

With 3.5mm inputs set to mic level I got plenty of gain with rode videomic X. I'm not experiencing the level issues others on this forum have reported. Maybe my unit is from a later batch. But I haven't had a chance to check the quality of the audio - I'm just going by what I see on the levels, which is plenty of gain to spare.
Offline

John Paines

  • Posts: 5787
  • Joined: Tue Jul 28, 2015 4:04 pm

Re: Pocket 4K - weak preamps?

PostTue Dec 04, 2018 9:51 pm

Benjamin de Menil wrote:
Benjamin de Menil wrote:I just tried out the stereo videomic X with the pocket 4K's 3.5mm jack. With the mic seto to +20db mode ... I'm not experiencing the level issues others on this forum have reported.


From your description, you're experiencing exactly the same levels reported here. The difference is, the mic's amplifier is adding 20db to the signal. Set it to zero added gain, and see what happens.
Offline

Benjamin de Menil

  • Posts: 330
  • Joined: Wed Feb 04, 2015 9:04 pm

Re: Pocket 4K - weak preamps?

PostTue Dec 04, 2018 11:32 pm

John Paines wrote:
Benjamin de Menil wrote:
Benjamin de Menil wrote:I just tried out the stereo videomic X with the pocket 4K's 3.5mm jack. With the mic seto to +20db mode ... I'm not experiencing the level issues others on this forum have reported.


From your description, you're experiencing exactly the same levels reported here. The difference is, the mic's amplifier is adding 20db to the signal. Set it to zero added gain, and see what happens.


I just had to lower it to zero because I had too much gain, even with the pocket's gain at 50%. It looked like with gain set to 50% I was clipping the Pocket 4K's pres or AD at about -6dB. That would mean that at 50% gain it's not possible to get to 0dB. Could also be the Rode mic was saturating. Anyway, was fine once I set the mic to flat gain. I was recording a concert, drums and amplified instruments. I'll see how it fairs tomorrow with conversational level volumes.

Generally speaking, I'd always get as much gain out of the mic as possible, because I figure the mic's gain is better than the camera's. With Rode video mics, it doesn't seem to me that my version of the Pocket has a problem.
Offline

Joe Giambrone

  • Posts: 19
  • Joined: Sun May 20, 2018 9:27 pm
  • Real Name: Joe Giambrone

Re: Pocket 4K - weak preamps?

PostWed Dec 05, 2018 12:05 am

This is new, and potentially important:

Does it mean the issue is solved, and it was just a matter of the correct setting?


I just got of the phone with BM support and discovered something that may be helpful to people using 3.5mm inputs:

The 3.5mm inputs can be set to line level or mic level. But the mic level option is not available in the menu if one of the channels is set to 3.5mm line. So before setting the first side to 3.5mm mic, make sure the other side isn't set to one of the 3.5mm line options. The reverse is true for discovering line level options if you have a side set to mic level.

With 3.5mm inputs set to mic level I got plenty of gain with rode videomic X. I'm not experiencing the level issues others on this forum have reported. Maybe my unit is from a later batch. But I haven't had a chance to check the quality of the audio - I'm just going by what I see on the levels, which is plenty of gain to spare.
Offline

John Paines

  • Posts: 5787
  • Joined: Tue Jul 28, 2015 4:04 pm

Re: Pocket 4K - weak preamps?

PostWed Dec 05, 2018 12:23 am

Joe Giambrone wrote:This is new, and potentially important:

Does it mean the issue is solved, and it was just a matter of the correct setting?


No. He had some user error to contend with. It sounds like his mic is "hot" to begin with (and may have additional amplification even at zero), and he was recording loud electric instruments and drums. Too many unknowns here to conclude much of anything.
Offline

Gene Kochanowsky

  • Posts: 1073
  • Joined: Sun Sep 20, 2015 12:11 am
  • Location: Tallahassee, FL

Re: Pocket 4K - weak preamps?

PostWed Dec 05, 2018 2:39 am

Benjamin de Menil wrote:The 3.5mm inputs can be set to line level or mic level. But the mic level option is not available in the menu if one of the channels is set to 3.5mm line. So before setting the first side to 3.5mm mic, make sure the other side isn't set to one of the 3.5mm line options. The reverse is true for discovering line level options if you have a side set to mic level.


That's weird and unexpected. I hope BM considers this a bug. I would expect 3.5mm Line and Mic should be selectable no matter what the other channel is set to.
Offline

John Paines

  • Posts: 5787
  • Joined: Tue Jul 28, 2015 4:04 pm

Re: Pocket 4K - weak preamps?

PostWed Dec 05, 2018 2:42 am

Gene Kochanowsky wrote:That's weird and unexpected. I hope BM considers this a bug. I would expect 3.5mm Line and Mic should be selectable no matter what the other channel is set to.


There's only one 3.5mm jack (with right/left channels), so how could you have line and mic levels at the same time? It's one or the other, for both channels.
Offline

Gene Kochanowsky

  • Posts: 1073
  • Joined: Sun Sep 20, 2015 12:11 am
  • Location: Tallahassee, FL

Re: Pocket 4K - weak preamps?

PostWed Dec 05, 2018 2:52 am

John Paines wrote:
Gene Kochanowsky wrote:That's weird and unexpected. I hope BM considers this a bug. I would expect 3.5mm Line and Mic should be selectable no matter what the other channel is set to.


There's only one 3.5mm jack (with right/left channels), so how could you have line and mic levels at the same time? It's one or the other, for both channels.


I agree, however on my camera I do not see selections for both 3.5mm line and mic unless the other channel is set to an input other than 3.5mm. Looks like a bug. Otherwise if both channels are set to 3.5mm line then mic is not selectable on either channel and visa versa.
Last edited by Gene Kochanowsky on Wed Dec 05, 2018 2:55 am, edited 1 time in total.
Offline

Denny Smith

  • Posts: 13131
  • Joined: Thu Aug 01, 2013 4:19 pm
  • Location: USA, Northern Calif.

Re: Pocket 4K - weak preamps?

PostWed Dec 05, 2018 2:53 am

The Ursa Mini Pro OS, which the Pocket 4K is using, has two audio channels that are independent of each other and each channel can be individually selected (think stereo left/right) between the two audio input sources, XLR and XLR AES. Where the Original Pocket and Micro only has one audio source connection the 3.5 stereo inlut, so both channels were selected together from mic to line.

My guess, looking at the manual, the new Pocket 4K has a XLR inlut and two channel 3.5mm input. So the OS is Since the two are locked to gather on the 3.5 connection, both sides/channels need to be switched from mic to line, so you need to switch channel 1 and channel 2.

In theory, you could select one channel from the 3.5 and the other channel from the XLR. This would make sense, if using a lav wireless set to mono for one channel on the 3.5 Mic inlut and the other channel set to XLR Mic. for a shotgun or hand held mic. like in an interview situation.
Cheers
Denny Smith
SHA Productions
Offline

Gene Kochanowsky

  • Posts: 1073
  • Joined: Sun Sep 20, 2015 12:11 am
  • Location: Tallahassee, FL

Re: Pocket 4K - weak preamps?

PostWed Dec 05, 2018 3:52 am

When this issue is described in text there seems to be some problems in understanding the issue, so for that instance I've made this little video.
Offline

Denny Smith

  • Posts: 13131
  • Joined: Thu Aug 01, 2013 4:19 pm
  • Location: USA, Northern Calif.

Re: Pocket 4K - weak preamps?

PostWed Dec 05, 2018 6:45 am

A Pix is word, and Yes, I see now what yiu are talking about, thanks for the video. This is not how the UM Pro/Broadcast audio menu works. Each audio channel is independent of the other, and one side can be mic, while the other side is line or AES.
So this indeed does seem to be either a design error or a bug in the OS.
Cheers
Denny Smith
SHA Productions
Offline

Kristian Lam

Blackmagic Design

  • Posts: 958
  • Joined: Tue Aug 21, 2012 1:11 pm

Re: Pocket 4K - weak preamps?

PostWed Dec 05, 2018 8:19 am

Unlike URSA Mini Pro, the stereo 3.5mm inputs can either only be line or mic, hence when mic level is selected for one side, the other has to be the same which is why line is not available.

I can see why this could be confusing and the interface wi be tweaked to better communicate that the other option is not available.
Offline

Wayne Steven

  • Posts: 3362
  • Joined: Thu Aug 01, 2013 3:58 am
  • Location: Earth

Re: Pocket 4K - weak preamps?

PostWed Dec 05, 2018 9:10 am

Thanks Kristan. I think people probably would like a 3 to 5 line 3.5mm jack in the future, where each line could he independently set to anything, if BM is listening? Can hook up some surround that way. BTW, when's the next camera announcement? (Have to try, CES, new micro?). :)
aIf you are not truthfully progressive, maybe you shouldn't say anything
bTruthful side topics in-line with or related to, the discussion accepted
cOften people deceive themselves so much they do not understand, even when the truth is explained to them
PreviousNext

Return to Cinematography

Who is online

Users browsing this forum: No registered users and 97 guests