When pushing the envelopes, we have experienced trouble with the USB drives when Multitrack recording. This can be particularly stressful when about to record a live show - and the recording USB is not recognised.
In this article we are only considering and testing 16bit @ 48kHz WAV recordings. This is good enough for making live videos of performances. If recording at larger bits and sample rates, you may need to consider larger and faster drives.
The purpose of this page was to start documenting what works, and what fails. Although we test all drives in the studio - some of them fail when out at a live gig. So its reliability we are looking for.
We also like to use low profile drives so we can leave them in the Soundcraft Ui24R without fear of damaging the USB port.
Many drives have failed us at critical moments... even before starting this page. It was all getting confusing.
This page is roughly edited and roughly researched. The drive tests should not be considered accurate. Its a outline - not conclusive - we are still testing and learning ourselves.
List of troublesome USB drives:
- SanDisk Ultra Fit, USB3.2 Gen1, 128GB.
- SanDisk SDCZ430. UltraFit. USB3.2 Gen1, 256GB. exFAT. (Plastic)(Would not recognise at a gig - after working and testing in the studio.)
List of USB Drives that work reliability (so far):
- SanDisk SDCZ43. USB 3.0, 64GB. FAT32. (Metal) (Sandisk Ultra Fit)
On Test:
- SanDisk SDCZ430. UltraFit. USB3.1, 64GB. FAT32. (Plastic)(Read speed of 130 MB/s)
Untrue USB specs
I don't know why, but USB manufacturers like SanDisk are not honest about their data rates. Advertise rates are sometimes wildly different to actual speds.
So we have tested a few USB drives ourselves. Check this page for real speeds of the devices that we have. USB Speed Test
Also to note, due to dodgy manufacturing practises and poor quality control, the drive we have may not perform like one you might get!
Specs According to Harman (the makers of the Soundcraft Ui24R)
"The Soundcraft Ui24R is capable of reading USB memory sticks formatted in FAT32 only, which limits the maximum storage capacity on a USB stick to 32GB. Therefore, all USB memory sticks must be 32GB or less in size. The Ui24R will not read any stick larger than this.
For optimal recording performance, the read/write speed of the USB memory stick must be 25mb/s or higher. Most USB memory sticks tout high read speeds but don't mention write speeds because they are actually slow at writing. This will result in either failed recording, or stuttering and audible artifacts on the recording."
So basically they are saying:
- 32GB or less
- FAT32
- Read/write of 25MB/s or faster.
Note it is the Write speed that is most important for Multitrack recording. Most USB manufacturers only state the Read speed. The USB write speed is often much less.
Contrary to this, we have been using larger drives.
Clearly Harman does not understand SI units - so their specified data rate does not make sense as "mb/s". "m" stands for milli (0.001). "B" stands for byte. "M" stands for Mega (1000). "b" I dunno... maybe they think it is bits? There are 8 bits in a byte.
So we assume 25mb/s means 25 Mb/s - or 25 Mega Bytes per second. This equates to 200mbps (mega bits per second).
File Sizes
From our last multitrack recording, a 130min recording, mono, 48kHz, 16 bit WAV, track used 718Mb.
So the file size is approximately 5.52Mb per minute, per track.
Thus, for a 4hr recording, 10 tracks, the drive would need to be 13.2 GB.
Thus, for a 4hr recording, 16 tracks, the drive would need to be 21.2 GB.
Generally our longest live set is 3hrs. So a 32GB drive should be good for multitrack recording.
FAT32 Limitations
The FAT32 file system has two primary limits:
- a maximum file size of 4 GB
- a theoretical maximum partition size that can reach up to 8 TB
Windows' built-in tools historically limited partition creation to 32GB limit.
We use this tool to format USB drives larger than 32GB.
For a 64GB drive, we'll use an allocation size of 32768.
(Some sources say 4096 is better for old USB readers).