Q&A - Aux In and Recording

How to record music on B2

The basic steps are

  1. Connect your turntable/cassette player etc to the B2 Aux In
  2. Select Aux on the B2
  3. Press REC to start recording
  4. Press Stop to stop recording
  5. Repeat from 3 as necessary
  6. Select HDD
  7. Transfer the recordings to the hard disk with Settings->Get Recordings
  8. You will find the music in an album called “Recordings”
  9. Rename the Recording so it won’t be overwritten
I recommend you make a few short trial recordings to get an idea for the process before setting about transferring your entire vinyl collection. And make frequent backups. Recording and renaming is quite labour intensive so its worth taking extra care not to lose your work.
Here is a little more detail and explanation
1) There are a few ways you might connect the music source to the B2 Aux In.

  1. A low end cassette player might have a headphone output so you will need a 3.5mm stereo jack to 3.5mm stereo jack lead. You should adjust the volume on the cassette play as loud as it will go without distorting when you play through the B2.
  2. An amplified turntable may typically have a lead with twin phono plugs - you will need a twin phono to 3.5mm stereo jack adaptor to connect it to B2
  3. A portable radio may have a headphone output so you will need a 3.5mm stereo jack to 3.5mm stereo jack lead.
  4. An unamplified turntable with raw cartridge output needs a phono preamplifier. You can buy these as stand alone gadgets but - assuming you already listen to your turntable - you will have an amplifier with a phono input. So you can either feed the line out of the amplifier to the B2 - usually a twin phono to 3,5mm stereo jack lead. Or you can connect the headphone output of the amplifier to the B2. The 3.5mm stereo jack to 3.5mm stereo jack lead will be needed but you may also need a ¼ inch to 3.5mm adaptor if your amplifier has a traditional ¼ inch headphone jack.
2) Select Aux on the B2 remote control. This will reboot the B2 in a mode that allows the Raspberry Pi to make recordings - but it disconnects the hard disk and internet. You should now hear your music source playing through the B2 speakers. Though nothing is being recorded yet. Now is a good time to play with your connections and volume levels. You may notice that if you touch the tip of one of the connectors on the lead feeding into the B2 that you get a crackle or hum - this is good and it's often a quick way to check that side of the system is working.

3) Start your music playing and press REC on the remote control. The B2 LED will flash and the display will show the current recording length and the name of the track. Each recording doesn’t have to correspond to a track. It could be the side of an album or cassette or it could be a radio program. You could even turn the vinyl album over quickly and record the other side on the same track. The recording is an uncompressed WAV file and it is stored temporarily on the SD card.
4) Press stop to stop recording.

5) Repeat from 3 - each recording will be given a new name like track 1, track 2.

6) Once you have made all the recordings that you want in one “album” - select HDD on the remote. This will reboot the B2 so that you can transfer the recordings to hard disk and listen to them.

7) Transfer the recordings from SD card to HDD with Settings->Get Recordings.
8) You can now listen to your recordings - search for “Recordings” and press play.

9) Recordings from Aux In are stored as tracks in an album called “Recordings” and artist “Unknown”. Let’s say you actually recorded a vinyl album - Dark side of the Moon by Pink Floyd and you recorded each side as a single track. So side one is recorded as track 1 and side two is recorded as track 2. At the very least you should rename the album so that subsequent recordings do not overwrite it. You can rename using the front panel or the Web UI. On the front panel search for “Recordings” then in the album menu choose Rename Album then repeat and pick Rename Artist. It's quicker on the Web UI - search for the “Recordings” album and double click to rename Album and Artist at the same time. You can delete any recordings you don’t want to keep. Either whole albums or individual tracks.

Vinyl Track Splitting 

"Hi Martin,
I have managed to record from vinyl to the B2 through the headphone socket, each side records as one track and I wondered if there is any way to get it to record each track individually or would I need to stop and record each track? I understand some software doesn't automate the creation of separate tracks. Great product.
Many thanks for your assistance. Terry"

Hi Terry. I think the short answer is you need to do the track splitting manually. I have used automatic track splitting - a piece of software called Audiograbber - but its not 100% accurate - not seeing gaps where they should be or splitting tracks in the middle. I'm sure it could be done better but it would amount to an audio editor and no less work for you. Martin

More on the Recording change of 3rd December

The Raspberry Pi has limitations around its USB system that mean that the wireless dongle or hard disk can interfere with the capture of music from aux/line in. This could affect Aux playback or more likely Recording from Aux - because of writes to the hard disk.

Reducing the speed of the USB almost eliminates this problem but I discovered there can still be an occasional dropped sample.

To combat this I modified the system to disable wireless (actually anything in USB A) and the hard disk when USB speed is set to low - for crackle free Aux In. This means that recordings must be sent to the SD card while in Low Speed - because the hard disk is disabled remember.

To listen to the recordings when you return to High Speed mode you need to use function Settings->Get Recordings to collect the recordings from the SD card and put them on the hard disk.

I will in due course put a "wrapper" round this functionality so all this speed selection and transfer of recordings happens seamlessly when you change source.


FYI I believe the problem with the Pi stems from it using software to do a job that would often be done by a DMA channel. DMA has a latency in the microsecond region whereas software can have variable latency comparable with the one millisecond window required to process samples from the CODEC. 

B2 Owner Recording Guidelines

Here are some instructions on Recording sent in By Chris B - many thanks.

1) Update software.

2) To make it easier to find your recordings, go to Settings: Sorting and switch off A-Z indexing.

3) Go to Settings again and switch to Low Speed USB and allow machine to Reboot.

4) Choose Aux input, line up your input and press Record.

5) Play your input (vinyl or whatever). Mark off tracks by pressing the Record button twice - once to end the last track and once to start recording the next.

6) At the end of recording, press and hold Stop until B2 says Saving. Leave the machine to finish compressing files – there is a message on the display.

7) Go back to high USB speed and wait for reboot to complete.

8) Go to Settings and select Get Recordings to transfer temporary Recordings file to hard disk. Wait for Copying to finish.

9) Use Browse Albums and the down arrow to go back to last recording, titled Recordings, or use Search if it is not there. When Search gets down to a manageable number of matches, it is important to proceed in the right order - first Next, then up and down arrows to scroll through, then OK to make a selection.

9) Then choose Rename Album. If using the remote, note that you delete backwards by pressing Delete - not Back, like on the JB7. Renaming is easier through the User Interface. Click twice on a track or album title to enable an over-write.

10) When you have finished your line-in recording session, you might want to restore A-Z indexing but don't forget that will relocate the album you have just recorded into its alphabetical position.

Update 13th January

I just made the USB Speed selection automatic so no need to set USB Speed manually - just select Aux or HDD and it happens. Also fixed a bug that meant Recordings didn't show up immediately in alpha sorted lists so no need to switch sorting off now.

Cleanup Recording With Audacity?

"I don't have a Brennan currently but I'm thinking of buying one.

Hope this isn't too stupid a question. I'm using audacity to digitise my vinyl collection. If I connect my turntable to a Brennan and make a digital recording of a record, I believe it gets initially recorded onto an SD card. I presume that to manipulate it in audacity (split tracks, remove crackle etc) I would take the SD card out of the Brennan and plug it into my computer, is this right? Or should I transfer it to the Brennan HDD and thence to a USB? How do I get the cleaned up, edited, renamed album back on to the Brennan?"

Hi - interesting - B2 can't send individual tracks to USB at the moment so your idea of cleaning up the wav files while they are on the SD card would work. Provided that you can persuade the PC to read them. You will find the recordings in the third partition on the SD card - Martin

Click and Scratch Filter

Do you have plans to incorporate software into the B2 that will eliminate tape hiss or clicks, pops and scratches from vinyl records automatically when ripping them into the B2? The record function could have the options of CD, Tape, or Vinyl, with the best noise elimination automatically set for each option.

Hi David
Sorry no - this job is already done very well by off the shelf programs - like Magix Audio Cleaning Lab.