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Apps to the rescue to record from USB on android?

Posted by admin |

I tried to record sound to a Motorola G5 through a USB sound card connected via an OTG adapter. Didn't work although playback worked. On a Nexus phone playback didn't work either.

It turns out USB sound card support is skimpy even in newer versions of Android.

One solution that is recommended on a forum is USB Audio Recorder - Apps on Google Play. The app has its own USB driver and their site shows support for a lot of phones and a lot of audio interfaces, including some really fancy ones.

But its free version available from their web site behaves lik a zip file on the phone, instead of as an apk, despite having the right suffix and being in the same folder as other working apks that can demonstrably be installed, downloaded with the same program.

I found also n-Track Studio Music DAW - Apps on Google Play but it wants to read my contacts. I'll see if I can turn that off and see how it behaves.

Feb 18, 2019 11:55

Best mics under €150 judging from the male soul sample at Thomann

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These five microphones I selected from going through most of the sub €150 large diaphragm mics on their site listening on the male soul dry sample through my my laptop speakers, and then ranked the below five between themselves by using a Sony MDR-XB950 (a so-so) headset listening to the same sample. A couple of mics on their site did not have the soul sample and were ignored. No mics between €119 and €150 made the list, as can be seen below:

Rank Name Price Interface Comment
1 Samson G-Track Black €105 USB 16-bit Gorgeous sound, even truer than the C03U, but with a bit of personality (this has a different soul sample than the others)
2 Samson C03U €89 USB 16-bit Great sound, but with a weird distortion, which might be from my headphones still sounds very honest. Shines on the processed version, is best there.
3 Audio-Technica AT2020 €89 XLR/48V Slightly tinny but still great
4 Superlux E205 €38 XLR/12-48V sounds fantastic over laptop speakers but loses its luster in the MDR-XB950 headphones but shines again in the Sony MDRCD480 phones. As somebody said in the reviews, this mic sounds a lot better that ithas the right to.
5 the t.bone SC 1100 €119 XLR/48V weird wandering sound in headphones

Audio-Technica AT2020 USBi and AT2020 USB+ sounded worse than the XLR Audio-Technica AT2020 listed above.

Superlux E205USB sounded worse than the XLR Superlux E205 listed above.

The Rode NT-1 is good but felt too dull, but might come to life with post-processing.

The 24-bit Samson G-Track Pro did not have the sound samples.

Disclaimer: Don't rely too much on random blog posts :)

Update 2019-02-19

I have now listened through a better set of headphones (Sony MDRCD480), and I still believe the above mics are the best in their selection, but I am less sure about the order between them. I also listened to the female soul voice and the AT-2020 does the best job there.

Some between €150 and €200 that sound fine

Audio-Technica AT 2035 €154

the t.bone SCT 800 – Thomann UK €175 sounds nice

Feb 17, 2019 11:25

Idea: An Android audio recorder that streams VU data over UDP

Posted by admin |

Let's say you want to use mobile phones to record sound locally, but you want to be sure that they are all recording. One way could be to have an app that streams volume data to a server on the Internet. In that way you could have a web page that gives you an overview of all devices recording.

Feb 16, 2019 01:29

TIL on audio: Small diapraghm mics, Ardour, 24 bit sound & podcastage

Posted by admin |

Small/large diaphragm condenser mics

I've wondered a bit why podcasters are using the old style large membrane mics of yonder. You could see these mics in '80s music videos when they wanted to be retro, such as Robert Palmer's "Johhny and Mary" and Ultravox "The Voice".

The Neumann mic company has a page on this: What Is the Difference Between Large and Small Diaphragm Microphones?

It turns out that strictly speaking small diaphragm mics are better, objectively seen (or, uhmm, objectively heard…). But many people like the sound characteristics of large diaphragm mics. I actually like my very cheap T.bone headset mic ,which is from the cheapest T.bone wireless system. Maybe I'm a small diaphragm mic man.


Bandrew Scott's Podcastage is a fantastic Youtube channel that tests a lot of podcast gear thoroughly and in good spirits. A gem.

Best USB Microphone Under $100 (Oct 2016) - YouTube
What's the Best USB Sound Card / Audio Adapter? - YouTube
What's the Best Mic & How To Select the Right Mic (For Beginners) - YouTube

Which mic should you choose?

Podcastage come through with a great guide on his web site: — Bandrew Scott

Plosives and sibilance

Turns out they are different things. Plosives is a powerful puff of air that is mainly a problem for large diaphragm mics with a lot of physical leeway.  Plosives can push those membranes to bottom out and they can take some moments to recover. Plosives are caused by "b" and "p" phonemes.

Plosives should be dealt with at recording time, apparently hard to correct in post production. Plosives are why you can see a screen in front of the big mics.

Sibilants are cause by "s" phonemes and similar. They can be dealt with in post by de-essing, which can be done with a two-pass compressor working in the high frequency band.

9 Techniques for Controlling Sibilance — Pro Audio Files

24-bit sound good

Podcastage explained this very well 16 bit vs. 24 bit Audio, What Should You Record At? (FAQ Series) - YouTube.

…and it's a no-brainer whan you think about it. You get a lower noise floor, and overall better quality. One thing that I will appreciate is that clipping ought to be a thing of the past. Since I started recording on cassettes on analgue, 0db is fine but in digital it most certainly is not! I have to get that into my brain better. With 24 bit (or -24 dB if you want) you can dial down and be far away from 0dB.


Ardour seems to run on my Pulseaudio Linux machine. I thought it wouldn't. I've slaved away in audacity for no reason! :D

Feb 16, 2019 07:20

Cheap large diaphragm mics I liked, listening to YouTube vids through a tinny laptop speaker

Posted by admin |

Audio-technica 4047 Oops, this isn't cheap! I started listening to samples at YouTube and thought "Wow this is great for a €70 mic". Turns out it's more like €700.

AKG P120 This is a €70 mic. I like what I hear on Youtube. Not as much as the 4047 above, but…

Samson C01U Pro USB



Feb 15, 2019 06:55

New insights into audio recording for video, from recent sessions

Posted by admin |

So for the situations I tend to end up in, one-on-one interviews, conversations in front of a white board with 2 or more people and sometimes a group chiming in with opinions. here are some ideas with regards to wired, wireless, digital, number of inputs, where to record and so forth.

Insight number 1 — tracks

A video camera usually only has two sound tracks. If you want more mics than two, you will have to record those on a different recorder, being it a camera, a dedicated recorder or a sound card connected to a computer. This means that you need to do synchronization. Unless you are fancy with SMPTE or something, that will be done by matching audio automatically. If you already need to do that, it does not take much more time to match many tracks algorithmically.

Insight number 2 — synchronization

If you already accept synchronizing multiple sources, you might as well have the recording device on the subject. The exception being that two mics should be wireless and their receivers should be mounted on the main camera to get sound and images in lockstep.

Insight number 3 — lapels don't scale

It's a lot of work to mic people up. Well, not a lot of work but it does not scale to when you have 12 or 50 people. A handheld wireless mic which can be passed around can be a good option in those cases. Also, everyone understands how a normal handheld mic works, so don't go for one where you talk at the side of it or something. You could also use a portable recorder for this with built-in mics. Actually that may be the best option.

Insight number 4 — no digital

No need to go digital. It makes more and more sense in our day and age to go digital from the mic to the recorder, but since most cameras don't have digital sound inputs afaik, you'll have to wait for that for a while. And for your other devices, if one believes this blog post's insights to be true, you'll use portable recorders on the person, which come to think of it is kind of all digital, just a very short chain.

A possible setup from these insights

  • Two wireless lavalier/lapel mics with the receivers mounted on-camera. You could go with just one and use the other channel for picking up ambient sound for synchronization
  • Any other cameras used, can take up sound from any fixed mics, including boom mics, indeed they should use this to get some synchronization signal.
  • Two people can be be mic'ed up with the wireless mics,
  • any others can be mic'ed up with lavalier mics that go to a recorder directly on the person's body.


Being a bit more concrete

A. One wireless lavalier mic for the main camera,

for example Røde rødelink newscaster/filmmaker (untested by me).

B. More lavalier mics

All other lavalier mics used, would have their own recording device on the person's body. Here you would need to find good but affordable such recorders, or use mobile phones.

  • Sony has an apparently great little mobile recorder under €100, the Sony ICD-UX560, but ideally you'd want to go a bit cheaper than that. Also, it does not come with a clip, but it does have a mic input with bias (3-5V for electret condenser mics).
  • A mobile phone with e.g. the aputure a.lav mic. I have that one and I don't like it, though.

    I suspect some mobile phones apply compression, maybe there is a way to avoid that. Record that note App works well on Android as a recorder in my experience.

There are some novelties in the field, such as the

  • Sennheiser Memory Mic, but I wish it came in black and not white. It's also at ~€200 a bit on the expensive side.
  • Same price range for the Tascam DR-10L Digital Audio Recorder with Lavalier Mic .
  • There is also the Zoom F1-LP, with lavalier mic, roughly the same price.


C. One handheld microphone

One handheld microphone that you can use for non-mic'ed up people to speak through. Here is a recorder that is of interest for this:

  • Tascam DR-10X Plug-On Micro Linear PCM Recorder (XLR). Aroung €100.
  • Here is one that even supplies 48V phantom power: Saramonic SR-VRM1 Plug-On Linear PCM Recorder for XLR Microphones, around €125.
  • You could also use a handheld voice recorder such as the Sony ICD-UX560 (again) as a handheld microphone.
  • Or even use a mobile phone, possibly with a mic sticking out to make it obvious where to talk. Make sure to have a good screen lock, but not so good that you can't unlock it because the finger print holder went to lunch.

Risks with this approach

  • Uneven sound quality with so many different recording devices.
  • Synchronization not working due to sound images being too different between different mics.
  • It's hard to know with confidence if a local device is indeed recording. With a central mixing desk you could check. Maybe if you use phones you could have them report over the Internet their recording status.
  • People wandering away with the devices.
    If a person wanders away with a wireless mic, you lose the mic. If he wanders away with a recorder however, you also lose the recording from that person! And you will have to edit them out of the video. A fitting punishment maybe :).

Go full insight— No wireless mics?

Actually for when only two subjects need to be recorded, two wireless camera mounted systems might be the best choice. Maybe one should never go go full insight, but you could probably get away with only portable recorders on the subjects, and sync up via the cameras' built-in mics. Actually for when only two subjects need to be recorded, two wireless camera mounted systems might be the best. But, you could probably get away with only portable recorders on the subjects, and sync up via the cameras' built-in mics.


Feb 15, 2019 04:40

Align videos with audio analysis & stack them in a multi sound file

Posted by admin |

With align-videos-by-sound, which is a python script/application you can align videos by their sound tracks.

After install, you can for example do this:

./bin/simple_stack_videos_by_sound_track --mode=direct --audio_mode=multi_streams tests/testfiles/3-secs-in.mp4 tests/testfiles/7-secs-in.mp4 tests/testfiles/full.mp4

It will present the 3 videos stacked in a "merged.mkv" file (one of the videos will be duplicated for symmetry), and the sound tracks from all 3 videos will be synced, for editing and mixing in e.g. Audacity (tested by me).

aligned tracks
Click to view full-size image…
Size: 80.3 kB

This is what it looks like in Audacity when you open the "merged.mkv" file. You can then export to multiple files and they will get the appropriate length of silence in the beginning.

Align-videos-by-sound is alpha software! And I am the maintainer of it, although all the heavy coding was done by Allison Deal (where i lifted the code from) and later Hiroaki Itoh.


Feb 14, 2019 01:25

An interesting guide on how to get an ecosystem going in your garden

Posted by admin |

A proof to me that anything can be interesting once somebody explains it in a way that makes your brain grok the particular field.

Feb 13, 2019 01:37

How to get a stereo wav file from a Canon C300 camera with MXF format using ffmpeg

Posted by admin |

This presumes you have been recording into the Canon C300 Mark I with two sound sources, split into separate channels. And you want the channels to be panned hard left and right, suitable for editing and comparison in e.g. Audacity (Although you can of course also export to different files and import).

This does the trick:

ffmpeg -i from_canon.MXF -filter_complex "[0:1] [0:2] amerge" -c:a pcm_s16le stereo.wav

Credit goes to FFMPEG: Need to mix dow multiple audio stream to single stereo - Stack Overflow

Software such as ffmpeg, Videolan Client (VLC) and audacity see Canon's MXF format as two separate sound channels inside a container, not as a left and right channel. In VLC you will only get one audio track for example, and you can switch to the other one if you want. So using ffmpeg, this won't work:

ffmpeg -i from_canon.MXF pcm_s16le stereo.wav

It will say that it will only include one audio stream in the wav file, althought there are two:

Stream mapping:
  Stream #0:1 -> #0:0 (pcm_s16le (native) -> pcm_s16le (native))

Mapping the channels into wav also won't work:

ffmpeg -i AA340601.MXF -map 0:1 -map 0:2 -c:a pcm_s16le all.wav

This will give the error:

WAVE files have exactly one stream
Could not write header for output file #0 (incorrect codec parameters ?): Invalid argument
Error initializing output stream 0:1 --
Feb 12, 2019 03:45