diff --git a/crazyflie-audio b/crazyflie-audio
index 9dd60d33..f7f3aa77 160000
--- a/crazyflie-audio
+++ b/crazyflie-audio
@@ -1 +1 @@
-Subproject commit 9dd60d33b743783334bd4230829f455b47d5ab76
+Subproject commit f7f3aa7760a42ed62dea02ee270952595b46cdaa
diff --git a/experiments/2020_09_17_white-noise-static/README.md b/experiments/2020_09_17_white-noise-static/README.md
new file mode 100644
index 00000000..6321d496
--- /dev/null
+++ b/experiments/2020_09_17_white-noise-static/README.md
@@ -0,0 +1,80 @@
+<!-- create this document in each new experiments folder, calling it README.md -->
+# EXPERIMENT NAME
+
+__Time__: Thursday 17.09.2020, ca. 15.00-18.00
+
+__Recorded by__: Frederike Dümbgen (ROS), Adrien Hoffet (Soundcard)
+
+__Place__: Audio room INR018, EPFL
+
+## Description
+
+###  Hardware
+<!--
+Checklist: 
+- Speaker type
+- Microphone type
+- Reference angle for DOA
+- Distance speaker-mic etc. 
+-->
+
+- Small speaker, center of bottom output mounted at 1.47 meters. 
+- Drone with audio deck, height of microphones at 1.47 meters. 
+- One measurement microphone at 1.73 meters, above the center of the drone, for control purposes.
+- Source at 0 degrees corresponds to 180 degrees in the drone's frame. 
+- Drone turned counter-clockwise by 20 and 45 degrees for different experiments.
+- Distance speaker to center of drone: 1.9 meters. 
+
+
+### Software
+<!--
+Checklist: 
+- Sampling rate
+- Motor thrust value 
+- Audio files used
+- Scripts used
+- Other parameters used
+-->
+
+- Software versions used: version0.2 for crazyflie-audio, crazyflie-firmware, audioROS
+- Sampling rate: 32000 kHz
+- Motor thrust value: 43000, set using parameter motorPowerSet.m1-m4
+- Used [crazyflie-audio/reaper/crazyflie_audio_measurements.RPP](https://github.com/LCAV/crazyflie-audio/blob/f7f3aa7760a42ed62dea02ee270952595b46cdaa/reaper/crazyflie_audio_measurements.RPP) file for speaker and measurement mic (commit: f7f3aa7760).
+
+### Protocol
+<!--
+Checklist: 
+- Sound level calibration
+- Order of scripts run
+- Start/end times of recordings, synchronization
+-->
+
+- Sound level calibration: measured at the measurement microphone location, during the experiments at 45 degrees.
+  - Maximum source: 80 dB
+  - Propeller noise: 73.5 dB
+- Measurement microphone recorded during 45 degrees experiments. 
+- Order of scripts:
+  - `ros2 run crazyflie_crtp gateway`: start getting audio data
+  - `ros2 param set ...`: set `filter_snr_enable` etc., set motor speeds
+  - `*_bkp`: had to run this experiment again because forgot to record on soundcard side.
+  - `*_crash`: had to run this experiment again because drone stopped sending data half-way.
+  - run at the same time: `ros2 bag record -o ...`  and play (+record) the sound through the soundcard 
+  - stop bag file recording as soon as the sound reaches its end.
+
+### Data
+<!-- Explain folder naming etc.  -->
+
+- `export/`: Measurement microphone recordings.
+- `<motors flag>_<snr filter flag>_<propeller filter flag>_<source flag>`: Audio deck recordings, e.g. `motors_nosnr_noprops_nosource`: propellers on, `filter_snr_enable` set to 0, `filter_props_enable` set to 0, no source playing.
+- `photos`: Photos of the experiment setup.
+
+### Observations
+<!--
+Anything unusual that happened during the experiments, such as
+- Background noise
+- Connection problems, low data rates, etc. 
+- Hardware (battery failures, broken parts, etc)
+-->
+
+- Needed to change batteries 3 times. 
+- Needed to restart the drone a few times because it stopped sending any valid audio data. 
diff --git a/experiments/2020_09_17_white-noise-static/export/crazyflie_audio_measurements_motors_nosnr_noprops_nosource_45.wav b/experiments/2020_09_17_white-noise-static/export/crazyflie_audio_measurements_motors_nosnr_noprops_nosource_45.wav
new file mode 100755
index 00000000..7c5403e3
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diff --git a/experiments/2020_09_17_white-noise-static/export/crazyflie_audio_measurements_motors_nosnr_noprops_source_45.wav b/experiments/2020_09_17_white-noise-static/export/crazyflie_audio_measurements_motors_nosnr_noprops_source_45.wav
new file mode 100755
index 00000000..26012ecb
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diff --git a/experiments/2020_09_17_white-noise-static/export/crazyflie_audio_measurements_nomotors_nosnr_noprops_source_45.wav b/experiments/2020_09_17_white-noise-static/export/crazyflie_audio_measurements_nomotors_nosnr_noprops_source_45.wav
new file mode 100755
index 00000000..0e171de0
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diff --git a/experiments/2020_09_17_white-noise-static/motors_nonosnr_props_source_20/metadata.yaml b/experiments/2020_09_17_white-noise-static/motors_nonosnr_props_source_20/metadata.yaml
new file mode 100644
index 00000000..fec639da
--- /dev/null
+++ b/experiments/2020_09_17_white-noise-static/motors_nonosnr_props_source_20/metadata.yaml
@@ -0,0 +1,16 @@
+rosbag2_bagfile_information:
+  version: 2
+  storage_identifier: sqlite3
+  relative_file_paths:
+    - motors_nonosnr_props_source_20/motors_nonosnr_props_source_20_0.db3
+  duration:
+    nanoseconds: 36477265672
+  starting_time:
+    nanoseconds_since_epoch: 1600355061766242700
+  message_count: 258
+  topics_with_message_count:
+    - topic_metadata:
+        name: /audio/signals_f
+        type: audio_interfaces/msg/SignalsFreq
+        serialization_format: cdr
+      message_count: 258
\ No newline at end of file
diff --git a/experiments/2020_09_17_white-noise-static/motors_nonosnr_props_source_20/motors_nonosnr_props_source_20_0.db3 b/experiments/2020_09_17_white-noise-static/motors_nonosnr_props_source_20/motors_nonosnr_props_source_20_0.db3
new file mode 100644
index 00000000..26df5387
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diff --git a/experiments/2020_09_17_white-noise-static/motors_nosnr_noprops_nosource/metadata.yaml b/experiments/2020_09_17_white-noise-static/motors_nosnr_noprops_nosource/metadata.yaml
new file mode 100644
index 00000000..b036a566
--- /dev/null
+++ b/experiments/2020_09_17_white-noise-static/motors_nosnr_noprops_nosource/metadata.yaml
@@ -0,0 +1,16 @@
+rosbag2_bagfile_information:
+  version: 2
+  storage_identifier: sqlite3
+  relative_file_paths:
+    - motors_nosnr_noprops_nosource/motors_nosnr_noprops_nosource_0.db3
+  duration:
+    nanoseconds: 37002525685
+  starting_time:
+    nanoseconds_since_epoch: 1600353917851188065
+  message_count: 180
+  topics_with_message_count:
+    - topic_metadata:
+        name: /audio/signals_f
+        type: audio_interfaces/msg/SignalsFreq
+        serialization_format: cdr
+      message_count: 180
\ No newline at end of file
diff --git a/experiments/2020_09_17_white-noise-static/motors_nosnr_noprops_nosource/motors_nosnr_noprops_nosource_0.db3 b/experiments/2020_09_17_white-noise-static/motors_nosnr_noprops_nosource/motors_nosnr_noprops_nosource_0.db3
new file mode 100644
index 00000000..59b26cad
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diff --git a/experiments/2020_09_17_white-noise-static/motors_nosnr_noprops_source/metadata.yaml b/experiments/2020_09_17_white-noise-static/motors_nosnr_noprops_source/metadata.yaml
new file mode 100644
index 00000000..62b087ca
--- /dev/null
+++ b/experiments/2020_09_17_white-noise-static/motors_nosnr_noprops_source/metadata.yaml
@@ -0,0 +1,16 @@
+rosbag2_bagfile_information:
+  version: 2
+  storage_identifier: sqlite3
+  relative_file_paths:
+    - motors_snr_noprops_source/motors_snr_noprops_source_0.db3
+  duration:
+    nanoseconds: 35159385140
+  starting_time:
+    nanoseconds_since_epoch: 1600353226810441373
+  message_count: 223
+  topics_with_message_count:
+    - topic_metadata:
+        name: /audio/signals_f
+        type: audio_interfaces/msg/SignalsFreq
+        serialization_format: cdr
+      message_count: 223
\ No newline at end of file
diff --git a/experiments/2020_09_17_white-noise-static/motors_nosnr_noprops_source/motors_snr_noprops_source_0.db3 b/experiments/2020_09_17_white-noise-static/motors_nosnr_noprops_source/motors_snr_noprops_source_0.db3
new file mode 100644
index 00000000..0940ac8a
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diff --git a/experiments/2020_09_17_white-noise-static/motors_nosnr_noprops_source_20/metadata.yaml b/experiments/2020_09_17_white-noise-static/motors_nosnr_noprops_source_20/metadata.yaml
new file mode 100644
index 00000000..78ed3bc5
--- /dev/null
+++ b/experiments/2020_09_17_white-noise-static/motors_nosnr_noprops_source_20/metadata.yaml
@@ -0,0 +1,16 @@
+rosbag2_bagfile_information:
+  version: 2
+  storage_identifier: sqlite3
+  relative_file_paths:
+    - motors_nosnr_noprops_source_20/motors_nosnr_noprops_source_20_0.db3
+  duration:
+    nanoseconds: 35723698190
+  starting_time:
+    nanoseconds_since_epoch: 1600354781657743567
+  message_count: 216
+  topics_with_message_count:
+    - topic_metadata:
+        name: /audio/signals_f
+        type: audio_interfaces/msg/SignalsFreq
+        serialization_format: cdr
+      message_count: 216
\ No newline at end of file
diff --git a/experiments/2020_09_17_white-noise-static/motors_nosnr_noprops_source_20/motors_nosnr_noprops_source_20_0.db3 b/experiments/2020_09_17_white-noise-static/motors_nosnr_noprops_source_20/motors_nosnr_noprops_source_20_0.db3
new file mode 100644
index 00000000..4d61a247
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diff --git a/experiments/2020_09_17_white-noise-static/motors_nosnr_noprops_source_45/metadata.yaml b/experiments/2020_09_17_white-noise-static/motors_nosnr_noprops_source_45/metadata.yaml
new file mode 100644
index 00000000..525f3398
--- /dev/null
+++ b/experiments/2020_09_17_white-noise-static/motors_nosnr_noprops_source_45/metadata.yaml
@@ -0,0 +1,16 @@
+rosbag2_bagfile_information:
+  version: 2
+  storage_identifier: sqlite3
+  relative_file_paths:
+    - motors_nosnr_noprops_source_45/motors_nosnr_noprops_source_45_0.db3
+  duration:
+    nanoseconds: 35381351396
+  starting_time:
+    nanoseconds_since_epoch: 1600356449113685952
+  message_count: 172
+  topics_with_message_count:
+    - topic_metadata:
+        name: /audio/signals_f
+        type: audio_interfaces/msg/SignalsFreq
+        serialization_format: cdr
+      message_count: 172
\ No newline at end of file
diff --git a/experiments/2020_09_17_white-noise-static/motors_nosnr_noprops_source_45/motors_nosnr_noprops_source_45_0.db3 b/experiments/2020_09_17_white-noise-static/motors_nosnr_noprops_source_45/motors_nosnr_noprops_source_45_0.db3
new file mode 100644
index 00000000..3f3b2cad
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diff --git a/experiments/2020_09_17_white-noise-static/motors_nosnr_props_source_45/metadata.yaml b/experiments/2020_09_17_white-noise-static/motors_nosnr_props_source_45/metadata.yaml
new file mode 100644
index 00000000..f6b10660
--- /dev/null
+++ b/experiments/2020_09_17_white-noise-static/motors_nosnr_props_source_45/metadata.yaml
@@ -0,0 +1,16 @@
+rosbag2_bagfile_information:
+  version: 2
+  storage_identifier: sqlite3
+  relative_file_paths:
+    - motors_nosnr_props_source_45/motors_nosnr_props_source_45_0.db3
+  duration:
+    nanoseconds: 35852075879
+  starting_time:
+    nanoseconds_since_epoch: 1600356605916537822
+  message_count: 238
+  topics_with_message_count:
+    - topic_metadata:
+        name: /audio/signals_f
+        type: audio_interfaces/msg/SignalsFreq
+        serialization_format: cdr
+      message_count: 238
\ No newline at end of file
diff --git a/experiments/2020_09_17_white-noise-static/motors_nosnr_props_source_45/motors_nosnr_props_source_45_0.db3 b/experiments/2020_09_17_white-noise-static/motors_nosnr_props_source_45/motors_nosnr_props_source_45_0.db3
new file mode 100644
index 00000000..386d64c9
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diff --git a/experiments/2020_09_17_white-noise-static/motors_snr_noprops_source/metadata.yaml b/experiments/2020_09_17_white-noise-static/motors_snr_noprops_source/metadata.yaml
new file mode 100644
index 00000000..da8f524e
--- /dev/null
+++ b/experiments/2020_09_17_white-noise-static/motors_snr_noprops_source/metadata.yaml
@@ -0,0 +1,16 @@
+rosbag2_bagfile_information:
+  version: 2
+  storage_identifier: sqlite3
+  relative_file_paths:
+    - motors_snr_noprops_source/motors_snr_noprops_source_0.db3
+  duration:
+    nanoseconds: 36782337817
+  starting_time:
+    nanoseconds_since_epoch: 1600353564400653178
+  message_count: 232
+  topics_with_message_count:
+    - topic_metadata:
+        name: /audio/signals_f
+        type: audio_interfaces/msg/SignalsFreq
+        serialization_format: cdr
+      message_count: 232
\ No newline at end of file
diff --git a/experiments/2020_09_17_white-noise-static/motors_snr_noprops_source/motors_snr_noprops_source_0.db3 b/experiments/2020_09_17_white-noise-static/motors_snr_noprops_source/motors_snr_noprops_source_0.db3
new file mode 100644
index 00000000..73c7b7a1
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diff --git a/experiments/2020_09_17_white-noise-static/motors_snr_noprops_source_20/metadata.yaml b/experiments/2020_09_17_white-noise-static/motors_snr_noprops_source_20/metadata.yaml
new file mode 100644
index 00000000..f51702eb
--- /dev/null
+++ b/experiments/2020_09_17_white-noise-static/motors_snr_noprops_source_20/metadata.yaml
@@ -0,0 +1,16 @@
+rosbag2_bagfile_information:
+  version: 2
+  storage_identifier: sqlite3
+  relative_file_paths:
+    - motors_snr_noprops_source_20/motors_snr_noprops_source_20_0.db3
+  duration:
+    nanoseconds: 35231138672
+  starting_time:
+    nanoseconds_since_epoch: 1600355443738216240
+  message_count: 198
+  topics_with_message_count:
+    - topic_metadata:
+        name: /audio/signals_f
+        type: audio_interfaces/msg/SignalsFreq
+        serialization_format: cdr
+      message_count: 198
\ No newline at end of file
diff --git a/experiments/2020_09_17_white-noise-static/motors_snr_noprops_source_20/motors_snr_noprops_source_20_0.db3 b/experiments/2020_09_17_white-noise-static/motors_snr_noprops_source_20/motors_snr_noprops_source_20_0.db3
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index 00000000..e434dd2f
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diff --git a/experiments/2020_09_17_white-noise-static/motors_snr_noprops_source_20_crash/metadata.yaml b/experiments/2020_09_17_white-noise-static/motors_snr_noprops_source_20_crash/metadata.yaml
new file mode 100644
index 00000000..81f58666
--- /dev/null
+++ b/experiments/2020_09_17_white-noise-static/motors_snr_noprops_source_20_crash/metadata.yaml
@@ -0,0 +1,16 @@
+rosbag2_bagfile_information:
+  version: 2
+  storage_identifier: sqlite3
+  relative_file_paths:
+    - motors_snr_noprops_source_20/motors_snr_noprops_source_20_0.db3
+  duration:
+    nanoseconds: 28516887555
+  starting_time:
+    nanoseconds_since_epoch: 1600355214731626029
+  message_count: 179
+  topics_with_message_count:
+    - topic_metadata:
+        name: /audio/signals_f
+        type: audio_interfaces/msg/SignalsFreq
+        serialization_format: cdr
+      message_count: 179
\ No newline at end of file
diff --git a/experiments/2020_09_17_white-noise-static/motors_snr_noprops_source_20_crash/motors_snr_noprops_source_20_0.db3 b/experiments/2020_09_17_white-noise-static/motors_snr_noprops_source_20_crash/motors_snr_noprops_source_20_0.db3
new file mode 100644
index 00000000..0b27296e
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diff --git a/experiments/2020_09_17_white-noise-static/motors_snr_noprops_source_45/metadata.yaml b/experiments/2020_09_17_white-noise-static/motors_snr_noprops_source_45/metadata.yaml
new file mode 100644
index 00000000..11115678
--- /dev/null
+++ b/experiments/2020_09_17_white-noise-static/motors_snr_noprops_source_45/metadata.yaml
@@ -0,0 +1,16 @@
+rosbag2_bagfile_information:
+  version: 2
+  storage_identifier: sqlite3
+  relative_file_paths:
+    - motors_snr_noprops_source_45/motors_snr_noprops_source_45_0.db3
+  duration:
+    nanoseconds: 36007972496
+  starting_time:
+    nanoseconds_since_epoch: 1600356694455455056
+  message_count: 210
+  topics_with_message_count:
+    - topic_metadata:
+        name: /audio/signals_f
+        type: audio_interfaces/msg/SignalsFreq
+        serialization_format: cdr
+      message_count: 210
\ No newline at end of file
diff --git a/experiments/2020_09_17_white-noise-static/motors_snr_noprops_source_45/motors_snr_noprops_source_45_0.db3 b/experiments/2020_09_17_white-noise-static/motors_snr_noprops_source_45/motors_snr_noprops_source_45_0.db3
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index 00000000..9c4581bc
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diff --git a/experiments/2020_09_17_white-noise-static/motors_snr_props_source/metadata.yaml b/experiments/2020_09_17_white-noise-static/motors_snr_props_source/metadata.yaml
new file mode 100644
index 00000000..0330b8ec
--- /dev/null
+++ b/experiments/2020_09_17_white-noise-static/motors_snr_props_source/metadata.yaml
@@ -0,0 +1,16 @@
+rosbag2_bagfile_information:
+  version: 2
+  storage_identifier: sqlite3
+  relative_file_paths:
+    - motors_snr_props_source/motors_snr_props_source_0.db3
+  duration:
+    nanoseconds: 36231520769
+  starting_time:
+    nanoseconds_since_epoch: 1600353693851824270
+  message_count: 225
+  topics_with_message_count:
+    - topic_metadata:
+        name: /audio/signals_f
+        type: audio_interfaces/msg/SignalsFreq
+        serialization_format: cdr
+      message_count: 225
\ No newline at end of file
diff --git a/experiments/2020_09_17_white-noise-static/motors_snr_props_source/motors_snr_props_source_0.db3 b/experiments/2020_09_17_white-noise-static/motors_snr_props_source/motors_snr_props_source_0.db3
new file mode 100644
index 00000000..35b9d846
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diff --git a/experiments/2020_09_17_white-noise-static/motors_snr_props_source_20/metadata.yaml b/experiments/2020_09_17_white-noise-static/motors_snr_props_source_20/metadata.yaml
new file mode 100644
index 00000000..0b337b17
--- /dev/null
+++ b/experiments/2020_09_17_white-noise-static/motors_snr_props_source_20/metadata.yaml
@@ -0,0 +1,16 @@
+rosbag2_bagfile_information:
+  version: 2
+  storage_identifier: sqlite3
+  relative_file_paths:
+    - motors_snr_props_source_20/motors_snr_props_source_20_0.db3
+  duration:
+    nanoseconds: 35774104810
+  starting_time:
+    nanoseconds_since_epoch: 1600355573350771152
+  message_count: 209
+  topics_with_message_count:
+    - topic_metadata:
+        name: /audio/signals_f
+        type: audio_interfaces/msg/SignalsFreq
+        serialization_format: cdr
+      message_count: 209
\ No newline at end of file
diff --git a/experiments/2020_09_17_white-noise-static/motors_snr_props_source_20/motors_snr_props_source_20_0.db3 b/experiments/2020_09_17_white-noise-static/motors_snr_props_source_20/motors_snr_props_source_20_0.db3
new file mode 100644
index 00000000..cd3aeb3c
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diff --git a/experiments/2020_09_17_white-noise-static/motors_snr_props_source_45/metadata.yaml b/experiments/2020_09_17_white-noise-static/motors_snr_props_source_45/metadata.yaml
new file mode 100644
index 00000000..49a68942
--- /dev/null
+++ b/experiments/2020_09_17_white-noise-static/motors_snr_props_source_45/metadata.yaml
@@ -0,0 +1,16 @@
+rosbag2_bagfile_information:
+  version: 2
+  storage_identifier: sqlite3
+  relative_file_paths:
+    - motors_snr_props_source_45/motors_snr_props_source_45_0.db3
+  duration:
+    nanoseconds: 35988325421
+  starting_time:
+    nanoseconds_since_epoch: 1600356799864266037
+  message_count: 219
+  topics_with_message_count:
+    - topic_metadata:
+        name: /audio/signals_f
+        type: audio_interfaces/msg/SignalsFreq
+        serialization_format: cdr
+      message_count: 219
\ No newline at end of file
diff --git a/experiments/2020_09_17_white-noise-static/motors_snr_props_source_45/motors_snr_props_source_45_0.db3 b/experiments/2020_09_17_white-noise-static/motors_snr_props_source_45/motors_snr_props_source_45_0.db3
new file mode 100644
index 00000000..98b04aa7
Binary files /dev/null and b/experiments/2020_09_17_white-noise-static/motors_snr_props_source_45/motors_snr_props_source_45_0.db3 differ
diff --git a/experiments/2020_09_17_white-noise-static/nomotors_nosnr_noprops_source/metadata.yaml b/experiments/2020_09_17_white-noise-static/nomotors_nosnr_noprops_source/metadata.yaml
new file mode 100644
index 00000000..32595872
--- /dev/null
+++ b/experiments/2020_09_17_white-noise-static/nomotors_nosnr_noprops_source/metadata.yaml
@@ -0,0 +1,16 @@
+rosbag2_bagfile_information:
+  version: 2
+  storage_identifier: sqlite3
+  relative_file_paths:
+    - nomotors_nosnr_noprops_source/nomotors_nosnr_noprops_source_0.db3
+  duration:
+    nanoseconds: 36598784313
+  starting_time:
+    nanoseconds_since_epoch: 1600353008929676515
+  message_count: 250
+  topics_with_message_count:
+    - topic_metadata:
+        name: /audio/signals_f
+        type: audio_interfaces/msg/SignalsFreq
+        serialization_format: cdr
+      message_count: 250
\ No newline at end of file
diff --git a/experiments/2020_09_17_white-noise-static/nomotors_nosnr_noprops_source/nomotors_nosnr_noprops_source_0.db3 b/experiments/2020_09_17_white-noise-static/nomotors_nosnr_noprops_source/nomotors_nosnr_noprops_source_0.db3
new file mode 100644
index 00000000..91efeec0
Binary files /dev/null and b/experiments/2020_09_17_white-noise-static/nomotors_nosnr_noprops_source/nomotors_nosnr_noprops_source_0.db3 differ
diff --git a/experiments/2020_09_17_white-noise-static/nomotors_nosnr_noprops_source_20/metadata.yaml b/experiments/2020_09_17_white-noise-static/nomotors_nosnr_noprops_source_20/metadata.yaml
new file mode 100644
index 00000000..e345e860
--- /dev/null
+++ b/experiments/2020_09_17_white-noise-static/nomotors_nosnr_noprops_source_20/metadata.yaml
@@ -0,0 +1,16 @@
+rosbag2_bagfile_information:
+  version: 2
+  storage_identifier: sqlite3
+  relative_file_paths:
+    - nomotors_nosnr_noprops_source_20/nomotors_nosnr_noprops_source_20_0.db3
+  duration:
+    nanoseconds: 35458771661
+  starting_time:
+    nanoseconds_since_epoch: 1600354371108241605
+  message_count: 191
+  topics_with_message_count:
+    - topic_metadata:
+        name: /audio/signals_f
+        type: audio_interfaces/msg/SignalsFreq
+        serialization_format: cdr
+      message_count: 191
\ No newline at end of file
diff --git a/experiments/2020_09_17_white-noise-static/nomotors_nosnr_noprops_source_20/nomotors_nosnr_noprops_source_20_0.db3 b/experiments/2020_09_17_white-noise-static/nomotors_nosnr_noprops_source_20/nomotors_nosnr_noprops_source_20_0.db3
new file mode 100644
index 00000000..e8534f3f
Binary files /dev/null and b/experiments/2020_09_17_white-noise-static/nomotors_nosnr_noprops_source_20/nomotors_nosnr_noprops_source_20_0.db3 differ
diff --git a/experiments/2020_09_17_white-noise-static/nomotors_nosnr_noprops_source_45/metadata.yaml b/experiments/2020_09_17_white-noise-static/nomotors_nosnr_noprops_source_45/metadata.yaml
new file mode 100644
index 00000000..2a777984
--- /dev/null
+++ b/experiments/2020_09_17_white-noise-static/nomotors_nosnr_noprops_source_45/metadata.yaml
@@ -0,0 +1,16 @@
+rosbag2_bagfile_information:
+  version: 2
+  storage_identifier: sqlite3
+  relative_file_paths:
+    - nomotors_nosnr_noprops_source_45/nomotors_nosnr_noprops_source_45_0.db3
+  duration:
+    nanoseconds: 33755884745
+  starting_time:
+    nanoseconds_since_epoch: 1600356259171666431
+  message_count: 193
+  topics_with_message_count:
+    - topic_metadata:
+        name: /audio/signals_f
+        type: audio_interfaces/msg/SignalsFreq
+        serialization_format: cdr
+      message_count: 193
\ No newline at end of file
diff --git a/experiments/2020_09_17_white-noise-static/nomotors_nosnr_noprops_source_45/nomotors_nosnr_noprops_source_45_0.db3 b/experiments/2020_09_17_white-noise-static/nomotors_nosnr_noprops_source_45/nomotors_nosnr_noprops_source_45_0.db3
new file mode 100644
index 00000000..403303fd
Binary files /dev/null and b/experiments/2020_09_17_white-noise-static/nomotors_nosnr_noprops_source_45/nomotors_nosnr_noprops_source_45_0.db3 differ
diff --git a/experiments/2020_09_17_white-noise-static/nomotors_nosnr_noprops_source_45_bkp/metadata.yaml b/experiments/2020_09_17_white-noise-static/nomotors_nosnr_noprops_source_45_bkp/metadata.yaml
new file mode 100644
index 00000000..7b3b1525
--- /dev/null
+++ b/experiments/2020_09_17_white-noise-static/nomotors_nosnr_noprops_source_45_bkp/metadata.yaml
@@ -0,0 +1,16 @@
+rosbag2_bagfile_information:
+  version: 2
+  storage_identifier: sqlite3
+  relative_file_paths:
+    - nomotors_nosnr_noprops_source_45/nomotors_nosnr_noprops_source_45_0.db3
+  duration:
+    nanoseconds: 35306097259
+  starting_time:
+    nanoseconds_since_epoch: 1600356064487444839
+  message_count: 239
+  topics_with_message_count:
+    - topic_metadata:
+        name: /audio/signals_f
+        type: audio_interfaces/msg/SignalsFreq
+        serialization_format: cdr
+      message_count: 239
\ No newline at end of file
diff --git a/experiments/2020_09_17_white-noise-static/nomotors_nosnr_noprops_source_45_bkp/nomotors_nosnr_noprops_source_45_0.db3 b/experiments/2020_09_17_white-noise-static/nomotors_nosnr_noprops_source_45_bkp/nomotors_nosnr_noprops_source_45_0.db3
new file mode 100644
index 00000000..60eccec1
Binary files /dev/null and b/experiments/2020_09_17_white-noise-static/nomotors_nosnr_noprops_source_45_bkp/nomotors_nosnr_noprops_source_45_0.db3 differ
diff --git a/experiments/2020_09_17_white-noise-static/nomotors_snr_noprops_source/metadata.yaml b/experiments/2020_09_17_white-noise-static/nomotors_snr_noprops_source/metadata.yaml
new file mode 100644
index 00000000..1a9af76a
--- /dev/null
+++ b/experiments/2020_09_17_white-noise-static/nomotors_snr_noprops_source/metadata.yaml
@@ -0,0 +1,16 @@
+rosbag2_bagfile_information:
+  version: 2
+  storage_identifier: sqlite3
+  relative_file_paths:
+    - nomotors_snr_noprops_source/nomotors_snr_noprops_source_0.db3
+  duration:
+    nanoseconds: 36795948293
+  starting_time:
+    nanoseconds_since_epoch: 1600353083404690124
+  message_count: 228
+  topics_with_message_count:
+    - topic_metadata:
+        name: /audio/signals_f
+        type: audio_interfaces/msg/SignalsFreq
+        serialization_format: cdr
+      message_count: 228
\ No newline at end of file
diff --git a/experiments/2020_09_17_white-noise-static/nomotors_snr_noprops_source/nomotors_snr_noprops_source_0.db3 b/experiments/2020_09_17_white-noise-static/nomotors_snr_noprops_source/nomotors_snr_noprops_source_0.db3
new file mode 100644
index 00000000..2ef429e1
Binary files /dev/null and b/experiments/2020_09_17_white-noise-static/nomotors_snr_noprops_source/nomotors_snr_noprops_source_0.db3 differ
diff --git a/experiments/2020_09_17_white-noise-static/nomotors_snr_noprops_source_20/metadata.yaml b/experiments/2020_09_17_white-noise-static/nomotors_snr_noprops_source_20/metadata.yaml
new file mode 100644
index 00000000..a08aaeb3
--- /dev/null
+++ b/experiments/2020_09_17_white-noise-static/nomotors_snr_noprops_source_20/metadata.yaml
@@ -0,0 +1,16 @@
+rosbag2_bagfile_information:
+  version: 2
+  storage_identifier: sqlite3
+  relative_file_paths:
+    - nomotors_snr_noprops_source_20/nomotors_snr_noprops_source_20_0.db3
+  duration:
+    nanoseconds: 33353073916
+  starting_time:
+    nanoseconds_since_epoch: 1600354592714115758
+  message_count: 201
+  topics_with_message_count:
+    - topic_metadata:
+        name: /audio/signals_f
+        type: audio_interfaces/msg/SignalsFreq
+        serialization_format: cdr
+      message_count: 201
\ No newline at end of file
diff --git a/experiments/2020_09_17_white-noise-static/nomotors_snr_noprops_source_20/nomotors_snr_noprops_source_20_0.db3 b/experiments/2020_09_17_white-noise-static/nomotors_snr_noprops_source_20/nomotors_snr_noprops_source_20_0.db3
new file mode 100644
index 00000000..ff249985
Binary files /dev/null and b/experiments/2020_09_17_white-noise-static/nomotors_snr_noprops_source_20/nomotors_snr_noprops_source_20_0.db3 differ
diff --git a/experiments/2020_09_17_white-noise-static/nomotors_snr_noprops_source_45/metadata.yaml b/experiments/2020_09_17_white-noise-static/nomotors_snr_noprops_source_45/metadata.yaml
new file mode 100644
index 00000000..8d36ca38
--- /dev/null
+++ b/experiments/2020_09_17_white-noise-static/nomotors_snr_noprops_source_45/metadata.yaml
@@ -0,0 +1,16 @@
+rosbag2_bagfile_information:
+  version: 2
+  storage_identifier: sqlite3
+  relative_file_paths:
+    - nomotors_snr_noprops_source_45/nomotors_snr_noprops_source_45_0.db3
+  duration:
+    nanoseconds: 35313576138
+  starting_time:
+    nanoseconds_since_epoch: 1600356360880813347
+  message_count: 227
+  topics_with_message_count:
+    - topic_metadata:
+        name: /audio/signals_f
+        type: audio_interfaces/msg/SignalsFreq
+        serialization_format: cdr
+      message_count: 227
\ No newline at end of file
diff --git a/experiments/2020_09_17_white-noise-static/nomotors_snr_noprops_source_45/nomotors_snr_noprops_source_45_0.db3 b/experiments/2020_09_17_white-noise-static/nomotors_snr_noprops_source_45/nomotors_snr_noprops_source_45_0.db3
new file mode 100644
index 00000000..dea8287f
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diff --git a/experiments/2020_09_17_white-noise-static/photos/DSC_1030.jpg b/experiments/2020_09_17_white-noise-static/photos/DSC_1030.jpg
new file mode 100644
index 00000000..6595b1cd
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diff --git a/experiments/2020_09_17_white-noise-static/photos/DSC_1031.jpg b/experiments/2020_09_17_white-noise-static/photos/DSC_1031.jpg
new file mode 100644
index 00000000..e4944cd9
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diff --git a/experiments/2020_09_17_white-noise-static/photos/DSC_1032.jpg b/experiments/2020_09_17_white-noise-static/photos/DSC_1032.jpg
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diff --git a/experiments/2020_09_17_white-noise-static/photos/DSC_1033.jpg b/experiments/2020_09_17_white-noise-static/photos/DSC_1033.jpg
new file mode 100644
index 00000000..688c5f1e
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diff --git a/experiments/2020_09_17_white-noise-static/photos/DSC_1034.jpg b/experiments/2020_09_17_white-noise-static/photos/DSC_1034.jpg
new file mode 100644
index 00000000..702dd2be
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diff --git a/experiments/2020_09_17_white-noise-static/photos/DSC_1035.jpg b/experiments/2020_09_17_white-noise-static/photos/DSC_1035.jpg
new file mode 100644
index 00000000..038c893e
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diff --git a/experiments/PROTOCOL_TEMPLATE.md b/experiments/PROTOCOL_TEMPLATE.md
new file mode 100644
index 00000000..35691620
--- /dev/null
+++ b/experiments/PROTOCOL_TEMPLATE.md
@@ -0,0 +1,53 @@
+<!-- create this document in each new experiments folder, calling it README.md -->
+# EXPERIMENT NAME
+
+__Time__: Day DD.MM.YYYY
+
+__Recorded by__: First Last, ...
+
+__Place__: Place, if necessary temperature etc. 
+
+## Description
+
+###  Hardware
+<!--
+Checklist: 
+- Speaker type
+- Microphone type
+- Reference angle for DOA
+- Distance speaker-mic etc. 
+-->
+
+### Software
+<!--
+Checklist: 
+- Sampling rate
+- Motor thrust value 
+- Audio files used
+- Scripts used
+- Other parameters used
+-->
+
+### Protocol
+<!--
+Checklist: 
+- Sound level calibration
+- Order of scripts run
+- Start/end times of recordings, synchronization
+-->
+
+### Data
+<!--
+Explain folder naming etc. 
+-->
+
+- `<folder1>`: 
+- `<folder2>`: 
+
+### Observations
+<!--
+Anything unusual that happened during the experiments, such as
+- Background noise
+- Connection problems, low data rates, etc. 
+- Hardware (battery failures, broken parts, etc)
+-->
diff --git a/src/audio_stack/audio_stack/spectrum_estimator.py b/src/audio_stack/audio_stack/spectrum_estimator.py
index 4a1eaa9c..bb8bb954 100644
--- a/src/audio_stack/audio_stack/spectrum_estimator.py
+++ b/src/audio_stack/audio_stack/spectrum_estimator.py
@@ -27,7 +27,7 @@
 
 # Beamforming method, available: 
 # - "das": delay-and-sum
-# - "mvdr": minimum-variacne distortionless response
+# - "mvdr": minimum-variance distortionless response
 BF_METHOD = "das"
 
 NORMALIZE = "zero_to_one_all"
@@ -38,12 +38,15 @@
 def normalize_rows(matrix, method="zero_to_one"):
     if method == "zero_to_one":
         normalized =  (matrix - np.min(matrix, axis=1, keepdims=True)) / (np.max(matrix, axis=1, keepdims=True) - np.min(matrix, axis=1, keepdims=True))
-        #assert np.max(normalized) == 1.0
-        #assert np.min(normalized) == 0.0
+        np.testing.assert_allclose(np.max(normalized, axis=1), 1)
+        np.testing.assert_allclose(np.min(normalized, axis=1), 0)
     elif method == "zero_to_one_all":
-        normalized =  (matrix - np.min(matrix)) / (np.max(matrix) - np.min(matrix))
-        #assert np.max(normalized) == 1.0
-        #assert np.min(normalized) == 0.0
+        denom = np.max(matrix) - np.min(matrix)
+        if denom == 0.0:
+            return matrix 
+        normalized =  (matrix - np.min(matrix)) / denom
+        assert np.max(normalized) == 1, np.max(normalized)
+        assert np.min(normalized) == 0, np.min(normalized)
     elif method == "sum_to_one":
         # first make sure values are between 0 and 1 (otherwise division can lead to errors)
         denom = np.max(matrix, axis=1, keepdims=True) - np.min(matrix, axis=1, keepdims=True)
@@ -53,6 +56,9 @@ def normalize_rows(matrix, method="zero_to_one"):
         np.testing.assert_allclose(np.sum(normalized, axis=1), 1.0, rtol=1e-5)
     else:
         raise ValueError(method)
+
+    if np.any(np.isnan(normalized)):
+        print("Warning: problem in normalization")
     return normalized
 
 
diff --git a/src/crazyflie_crtp/crazyflie_crtp/gateway.py b/src/crazyflie_crtp/crazyflie_crtp/gateway.py
index 90e90e41..7b6b555a 100644
--- a/src/crazyflie_crtp/crazyflie_crtp/gateway.py
+++ b/src/crazyflie_crtp/crazyflie_crtp/gateway.py
@@ -31,17 +31,26 @@
 N = 1024
 
 # Crazyflie audio parameters that can be set from here.
-PARAMETERS_TUPLES = [
+AUDIO_PARAMETERS_TUPLES = [
     ("debug", rclpy.Parameter.Type.INTEGER, 0),
     ("send_audio_enable", rclpy.Parameter.Type.INTEGER, 1),
-    ("min_freq", rclpy.Parameter.Type.INTEGER, 100),
-    ("max_freq", rclpy.Parameter.Type.INTEGER, 10000),
-    ("delta_freq", rclpy.Parameter.Type.INTEGER, 100),
-    ("n_average", rclpy.Parameter.Type.INTEGER, 1),
+    ("min_freq", rclpy.Parameter.Type.INTEGER, 200),
+    ("max_freq", rclpy.Parameter.Type.INTEGER, 7000),
+    ("delta_freq", rclpy.Parameter.Type.INTEGER, 40),
+    ("n_average", rclpy.Parameter.Type.INTEGER, 5),
     ("filter_snr_enable", rclpy.Parameter.Type.INTEGER, 0),
     ("filter_prop_enable", rclpy.Parameter.Type.INTEGER, 0),
 ]
 
+MOTOR_PARAMETERS_TUPLES = [
+    ("all", rclpy.Parameter.Type.INTEGER, 0),
+    ("m1", rclpy.Parameter.Type.INTEGER, 0),
+    ("m2", rclpy.Parameter.Type.INTEGER, 0),
+    ("m3", rclpy.Parameter.Type.INTEGER, 0),
+    ("m4", rclpy.Parameter.Type.INTEGER, 0),
+    ("enable", rclpy.Parameter.Type.INTEGER, 0),
+]
+
 
 class Gateway(Node):
     def __init__(self, reader_crtp, mic_positions=None):
@@ -64,11 +73,18 @@ def __init__(self, reader_crtp, mic_positions=None):
         self.reader_crtp = reader_crtp
 
         parameters = []
-        for param in PARAMETERS_TUPLES:
+
+        for param in AUDIO_PARAMETERS_TUPLES:
             self.declare_parameter(param[0])
             param_rclpy = rclpy.parameter.Parameter(*param)
             parameters.append(param_rclpy)
-        self.set_parameters_callback(self.set_audio_params)
+
+        for param in MOTOR_PARAMETERS_TUPLES:
+            self.declare_parameter(param[0])
+            param_rclpy = rclpy.parameter.Parameter(*param)
+            parameters.append(param_rclpy)
+
+        self.set_parameters_callback(self.set_params)
         self.set_parameters(parameters)
 
         # choose high publish rate so that we introduce as little
@@ -108,10 +124,14 @@ def publish_audio_dict(self):
         all_frequencies = np.fft.rfftfreq(n=N, d=1/FS)
         #frequencies = all_frequencies[:n_frequencies]
         try:
+            assert np.any(fbins>0)
+            if len(set(fbins)) < len(fbins):
+                #self.get_logger().warn(f"Duplicate values in fbins! unique values:{len(set(fbins))}")
+                return
             frequencies = all_frequencies[fbins]
             self.get_logger().info(f"Read fbins: {fbins}")
         except:
-            self.get_logger().warn(f"Ignoring fbins: {fbins}")
+            #self.get_logger().warn(f"Ignoring fbins: {fbins[:5]}")
             return
 
         signals_f = np.zeros((N_MICS, n_frequencies), dtype=np.complex128)
@@ -119,6 +139,11 @@ def publish_audio_dict(self):
             signals_f[i].real = signals_f_vect[i :: N_MICS * 2]
             signals_f[i].imag = signals_f_vect[i + N_MICS :: N_MICS * 2]
 
+        abs_signals_f = np.abs(signals_f)
+        if np.any(abs_signals_f[:3, :] > 1e5) or np.any(abs_signals_f[:3, :] < 1e-10):
+            #self.get_logger().warn(f"Ignoring audio: {abs_signals_f.flatten()[:5]}")
+            return
+
         # send data
         msg = SignalsFreq()
         msg.frequencies = [int(f) for f in frequencies]
@@ -134,7 +159,7 @@ def publish_audio_dict(self):
             msg.mic_positions = []
         self.publisher_signals.publish(msg)
 
-        self.get_logger().info(f"Published audio data.")
+        self.get_logger().info(f"{msg.timestamp}: Published audio data with fbins {fbins[[0, 1, 2, -1]]}")
 
     def publish_motion_dict(self):
         motion_dict = self.reader_crtp.motion_dict["data"]
@@ -170,30 +195,53 @@ def publish_motion_dict(self):
 
         self.prev_position_x = msg_pose.position.x
         self.prev_position_y = msg_pose.position.y
-        self.get_logger().info("Published motion data.")
-
-    def set_audio_params(self, params):
-        for param in params:
-            param_tuples = [p for p in PARAMETERS_TUPLES if p[0] == param.name]
-            assert len(param_tuples) == 1
-            if param_tuples[0][1] == rclpy.Parameter.Type.INTEGER:
-                old_value = (
-                    self.get_parameter(param.name).get_parameter_value().integer_value
-                )
-                new_value = param.get_parameter_value().integer_value
-            elif param_tuples[0][1] == rclpy.Parameter.Type.DOUBLE:
-                old_value = (
-                    self.get_parameter(param.name).get_parameter_value().double_value
-                )
-                new_value = param.get_parameter_value().double_value
+        self.get_logger().info(f"{msg_pose_raw.timestamp}: Published motion data.")
+
+    def set_params(self, params):
+        for param in params: 
+            param_tuples_audio = [p for p in AUDIO_PARAMETERS_TUPLES if p[0] == param.name]
+            param_tuples_motor = [p for p in MOTOR_PARAMETERS_TUPLES if p[0] == param.name]
+
+            if len(param_tuples_audio) == 1:
+                self.set_param(param, param_tuples_audio[0], "audio")
+            elif len(param_tuples_motor) == 1:
+                # TODO(FD) find more elegant way to do this
+                #for motor in [f"m{i}" for i in range(1, 5)]:
+                #    param = self.get_parameter(motor)
+                value = param.get_parameter_value().integer_value
+                if param.name == "all":
+                    [self.reader_crtp.cf.param.set_value(f"motorPowerSet.m{i}", value) for i in range(1, 5)]
+                    self.get_logger().info( f"changing all motors to {value}")
+                else:
+                    self.reader_crtp.cf.param.set_value(f"motorPowerSet.{param.name}", value)
+                    self.get_logger().info(f"changing {param.name} to {value}")
+                if value > 0:
+                    print("changing motorPowerSet.enable to 1")
+                    self.reader_crtp.cf.param.set_value("motorPowerSet.enable", 1)
             else:
-                raise ValueError(param_tuple)
+                raise ValueError(param)
+        return SetParametersResult(successful=True)
 
-            self.reader_crtp.cf.param.set_value(f"audio.{param.name}", new_value)
-            self.get_logger().info(
-                f"changing {param.name} from {old_value} to {new_value}"
+    def set_param(self, param, param_tuple, param_class):
+        if param_tuple[1] == rclpy.Parameter.Type.INTEGER:
+            old_value = (
+                self.get_parameter(param.name).get_parameter_value().integer_value
             )
-        return SetParametersResult(successful=True)
+            new_value = param.get_parameter_value().integer_value
+        elif param_tuple[1] == rclpy.Parameter.Type.DOUBLE:
+            old_value = (
+                self.get_parameter(param.name).get_parameter_value().double_value
+            )
+            new_value = param.get_parameter_value().double_value
+        else:
+            raise ValueError(param_tuple)
+
+        self.reader_crtp.cf.param.set_value(f"{param_class}.{param.name}", new_value)
+        self.get_logger().info(
+            f"changing {param.name} from {old_value} to {new_value}"
+        )
+        return 
+
 
 
 def main(args=None):
@@ -222,8 +270,10 @@ def main(args=None):
             while True:
                 time.sleep(1)
         except KeyboardInterrupt:
-            print("unset audio.send_audio_enable")
             cf.param.set_value("audio.send_audio_enable", 0)
+            cf.param.set_value("motorPowerSet.enable", 0)
+            print("reset audio.send_audio_enable and motorPowerSet.enable, wait for 1s...")
+            time.sleep(1)
 
     publisher.destroy_node()
     rclpy.shutdown()
diff --git a/src/topic_plotter/topic_plotter/audio.py b/src/topic_plotter/topic_plotter/audio.py
index 7346c06f..b53592fa 100644
--- a/src/topic_plotter/topic_plotter/audio.py
+++ b/src/topic_plotter/topic_plotter/audio.py
@@ -72,7 +72,7 @@ def listener_callback_spectrum(self, msg_spec, name="static", eps=YLIM_MIN):
         # compute and plot combinations.
         spectrum_sum = combine_rows(spectrum, "sum", keepdims=True)
         spectrum_sum = normalize_rows(spectrum_sum, NORMALIZE)
-        spectrum_product = combine_rows(spectrum, "product", keepdims=True)
+        spectrum_product = combine_rows(spectrum + 1e-1, "product", keepdims=True)
         spectrum_product = normalize_rows(spectrum_product, NORMALIZE)
 
         spectrum_plot = np.r_[spectrum_product, spectrum_sum]