Mobile Recording in General

Thanks again, @Fahri . The diagrams are especially helpful.

Unfortunately I cannot play the backing track from the phone as you describe - the Pixel 5 does not have a 3.5 mm headphone jack. I guess they figure that everybody is using bluetooth headsets these days. A wired headset can be used with a dongle to the USB-C port, but of course that is already in use with the DAI.

No problem - I have all my music related files on Dropbox so I can access them from a phone, tablet or pc, so I’m using another phone to play the backing track.

Prior to reading your post I realized that my Zoom B1Four could be useful here - great minds think alike. :smiley:

Right now the B1Four is connected to the UMC204HD through an “insert” which is an fX loop (yet another use for the versatile TRS connector). I plugged the 2nd phone into the aux input on the B1Four and I have my backing track.

Everything is now working exactly as desired except that all the audio (both bass and backing track) is on the left channel only, just as we discussed.

Since I’m not using the #2 channel for anything my plan is to move the B1Four to ahead of the DAI and feed the output into both channels of the DAI using a splitter like this:

Mono TS Female to 2 TS Male Splitter Cable

I would, however, like some reassurance that essentially bridging the two channels isn’t going to damage the DAI. :worried:

I’ve also approached the issue from other angles. If I view the video on my Linux PC using the VLC Media Player I can set the audio output to mono and problem solved. This is fine as long as I’m only making videos for my own critiquing.

How about converting the file? This could probably be done in a video editor, but I’ve looked at several videos and concluded that they all have very steep learning curves, at least for someone like me who has no experience with video editing. If anyone knows of a basic, intuitive easy to use video editor, I’d love to hear about it.

Fortunately, I found a simpler solution.

[WARNING: Serious old school computer geek stuff ahead!]

ffmpeg is a program installed by default on most Linux distributions that is a back end for many video related programs. It can be run from the command line.

I discovered that if I open a terminal window, navigate to the video file and run the following:

ffmpeg -i myvideo.mp4 -codec:v copy -ac 1  myvideomono.mp4    

where “myvideo.mp4” is the video file with the left channel audio and "myvideomono.mp4 will be whatever I want to call the new file to be produced which will leave the video unchanged and convert the audio to mono.

This only takes a few minutes to run and seems to work just fine.


@spidey9 I am really liking that you are bringing out of the box ideas here! Thanks a lot for keeping it as a dialogue!

This sucks I agree. You can of course use a little USB HUB that is separately powered which would have other benefits like not draining your phone’s battery but every little thing you add removes mobility… So I support the “second device for backing track” idea which I also use!

Actually the output of Zoom B1 Four can work both as stereo or mono. That is how you can use it with a headphone! That is what I was trying to show with the green line in my diagram (maybe not so clearly, NOTED!) and especially for this possibility I wanted to mention Zoom B1 Four.

For your setup what you need is a TRS to TS/TS splitter this way CH1 on your DAI will be left and CH2 will be right as intended!

Electrically what you need is this:

The most right one goes into Zoom B1 Four Output and the others to DAI CH1 and CH2…

But this is a super specific cable which kinda has only one use. To create this connection I have used some stuff lying around at home.

This 3.5mm to RCA splitter is very useful for a lot of connections and very common thing to have at home…

Two of these can convert the RCAs to 6.35mm jacks

Which is very common line in connection to mixers etc

And finally you need 3.5mm to 6.35mm adapter to connect the TRS to Zoom Output again very common thing

And when you connect all of this you have !

With this setup your issue with everything on one channel is resolved but I am totally digging the Linux command line stuff to convert video files like that. As I have mentioned some messages before I have been extracting the audio from video with a phone app which was converting it to mono on the fly and then rejoining the video and audio.

I wonder if I could create a simple android app for this :smiley: :smiley: :smiley:

Anyhooo, when I record at home. I always use my little mixer… It opens sooo many possibilities like more instruments, volume control on everything etc…


It’s easy to think outside the box when you don’t have the slightest idea what you’re doing. :laughing: :laughing:

It has at least one other use - this is exactly the cable I use to connect the B1Four into the insert (fXloop) on the UMC204HD. The TRS plug goes into the insert jack on the UMC204HD, the tip (black) TS plug goes to the B1Four input and the ring (red) TS plug goes into the output of the B1Four.

In other words, I have one of these cables right in front of me. I won’t be running the B1Four through the insert, so I can use it as you describe.

Thanks again - this is great information!


Hello everyone,

I have been searching for different ways to record mainly audio but also videos at our band practices. Recently I have been playing with two bands with similar configurations. It is usually an acoustic drum set, vocalist connected to a mixer, one electric guitar and one bas guitar with their own amps.

On one of the groups there is a second guitar (classical with integrated preamp) that also connects directly to the mixer.

So vocals (and second classical guitar) is coming through big monitors while the bass, electric guitar and drum set are their own sound sources.

This is the studio that we are using with the 5 people band:

My initial approach was the simplest which was pressing record on my smartphone which was near me (so near to the bass amp as well) :

Here is how it came out.

It was quite indicative on many occasions but but the input gain was not easy to set and over all sound quality drops significantly. Furthermore I had the intention to use my phone for recording video as well and the right position to record video is not always the best for audio…

So I have switched to another method where I tried to connect everyone through a mixer to my two channel audio interface ( Motu M2 ). The challenge here was to mic the drums properly but all I had were two dynamic microphones one over head one kissing the kick drums. Bass and electric guitar were going direct in. Motu M2 was connected to my phone through USB so I could record videos already…

This is a snippet of that night… Personally it was horrible. It took ages to cable everything and I did not have the time and patience of my band mates to set the mix properly. In the end the drums and bass simply were too low while the vocal and the guitar was quite clear. In any case this gave us a great indication on what quality we could achive.

Finally after a long research and some input from one of the drummers I decided to go for a field recorder.

Among many other videos on topic this was the most inspiring:

I was also going for an H1n myself (there was one for 50€ if I waited a month and 85€ brand new) but just before I was about to purchase a new one a notification for a second hand site informed me a much superior recorder announcement dropped in. Which I literally jumped on…

This thing must be the epitome of mobile recording! It has the amazing two condenser mics which were already fine to take care of what I needed initially but there are all these integrated features which makes it crazy good:

  • Line out to connect to a camera or phone for video recording
  • Two XLR combo inputs if I want to connect the guitars
  • Two mic capsule can be replaced with other types of mics and/or an extension device which brings two more XLR combo jacks.
  • This mic capsule also has an input for a stereo input either for line in or mic which I can connect the guitar and bass direct outs or the mixer output if necessary.
  • You set all the levels on the device itself to match the maximum input to -12dB and even then you can record a secondary backup file which is 12dB lower incase something clips.
  • There is a USB port to connect to PC which can also work as an audio interface!
  • When you connect line out to your phone to record videos you can also record on the device at the same time.
  • It works on two AA batteries and can record for 5-6 hours like that (specs)

All and all the possibilities become infinite with this thing!

This is the recording with the 5 people band in the big studio that I also shared in the mic thread

Here I intuitively setup the gain depending on the drum set and told everyone else to set their volumes accordingly so that I can get -12dB but after a couple of songs everything went about all over the place. While playing I was not able to hear my bass anymore but on the recording it is loud and clear (probably the wavelength thing where you hear the bass better when you are 6m away )

The recorder was on a small stand on the bar table on the left just from the entrance (you can see it on the video). It was directed towards the drums.

I have ordered a mic stand adapter (it has a camera type of screw under it ) so That I can fix it somewhere else…


Today I have received some adapters to connect my new toys to my older toys

Here the line out of Zoom H5 is connected to Gopro as external mic. I need to make some testing to set the levels right.


Sounds much better. Great job.
Levels aside, it no longer sounds saturated.
The bass is just a little loud, and nothing wrong with that, as we want to hear the bass skills when posting here for the most part.
so it is a huge improvement, obviously, your investments have paid off greatly.


Yeah those Zoom recorders are great.


Yeah that’s another great thing about these field recorders that they have the easy to read level meter on their screen. Motu m2 also has some bars but no reference to what db they represent…

1 Like

You have insane amount of high end on that recording to the point of ripping my head off. Is there some sort of internal EQ on that thing or it’s by default so high end intensive?

I also thought that, I am using this backing track here

Which might be created by removing the bass from the original not so surgically…

Also it might be the preamp of the old Gopro which I don’t have any control on…

Later I will make a side by side comparison…

Thanks for the input!

1 Like

I think it’s mostly the backing track.

1 Like

I tend to agree. Here is a quick comparison (not so quick to edit!) Between locally saved file and the audio integrated to the Gopro video.

Gopro puts on an amplification that I cannot control. I can only control the output signal of the Zoom H5 which I put -25dB of reduction on line out. Still the video recorded by Gopro was quite loud.

Gotta make some tests to find the correct levels. Write them somewhere and always use like that…

@Noisembryo sorry for the head trauma mate…


I don’t think it’s a backing track, sure it has a bit harsh sounding cymbals but nothing to worry about. Problem is something in your chain is amplifying that signal or even distorting it so that harshness becomes excessive.

Zoom without Gopro sounds OK in this video although backing track is still sounding brighter than when you listen to it alone.