Stating that USB is too slow for 32 channels is not being informed. What is a "normal USB thumb drive"? V3.1 Super-speed + is specked at 10 Gbits/sec and 3.0 at 5.0 Gbits/se. more than enough to handle 32 channels at ~50Mbits/sec. Sort of like comparing a VW Super beetle to a Ferrari F1. You then state that a USB SSD is OK for the job, Really! V2.1 sticks probably won't work unless it's a real V2.1 High Speed (480 Mbits/sec). Keep in mind that Specs and real speed differ greatly. A speed check would be in order. Oh, does Mackie even spec their port? Then there is that USB driver that is in your system! Not so simple is it.
OK, a bit less adrenaline and aggression, please...
I'm not uninformed - I wasn't stating that USB is too slow but that the typical USB thumb drive is too slow - and that's not because of the speed of USB, but of its internal speed of writing to flash storage. That's why I recommended a hard drive (HDD) or an SSD drive - because their internal writing speed is far superior to the garden-variety thumb drive.
When recording 32 channels, you create a data stream of around 4.6-5 MB per second. One of the more common USB 2.0 sticks, the Sandisk Cruzer 64 GB, can only write 3,25 MB per second. Now if the DL32 can't write the data to the drive at a fast enough rate, it will probably just drop chunks of the wave file while the drive isn't ready and only continue writing when the drive is ready again. Since the audio stream has since moved on, audio gets lost.That's what creates the glitches.
Yes, there are faster flash USB drives that can write 10MB per second and more, so it could be possible to keep up with the stream, but the problem here is that they'll realize that speed ON AVERAGE, so you can't be sure that there isn't a temporary hiccup where the writing speed will drop below 4.5 MB/s, creating glitches. So using flash drives for serious 32-channel recording is not something I'd recommend. If you really have a very fast flash drive, you should be sure that you test its long-term performance in advance of any serious recording.
A hard disk drive can write about 50-160 MB/sec, depending on its rotation speed (typically smaller portable hard drives don't run the 7200 rpm that higher-performance internal drives do) and other factors. A current SSD drive will even have a writing speed of around 500 MB/s. So these drives have definitely enough writing performance to easily keep up with the data flow from the DL32R, with a wide safety margin - that's why I say that they are OK for the job (because they won't get choked by the speed of incoming data).
It has nothing to do with the USB speed, so all the noise about USB V3.1, 3.0 or 2.1 isn't helpful at all here. USB speed is only the TRANSFER rate between the connected devices. What is the choking point here is the writing speed at the end of the transfer - sort of like the Ferrari F1 being stuck in a traffic jam...
In real life terms, USB 2.0 data transfer performance is around 35 MB/s, so definitely enough to transfer a 32 channel data stream. Therefore I'd assume Mackie has built a standard USB 2.0 port into the DL32R - no need to spend more on components if you don't need higher performance, right? But all relevant USB3 external drives will work on a USB 2 connection (at USB 2 speeds), so yes, an external SSD drive could be a good solution to record on.
And not at all sure what you mean with the "USB driver that is in [my] system"? The only relevant communication here is between the DL32R and the USB drive - my system doesn't come into this at all.
So it actually
is simple: any USB drive (2.0 and higher) that is internally capable of sustaining a writing speed above 5 MB/s (without ever dropping below it) is fit to do the job.
I recommended an SSD drive for busy / vibrating stages, because a hard disk (with rotating platters) has a mechanism built in that will park the read/write heads on an unused area when it senses stronger vibrations - to avoid so-called head-crashes, which can cause unrecoverable data loss. During this time, the drive will not be able to write data, so again writing speed will momentarily drop below 5MB/s - glitches will occur. An SSD drive has no moving parts, therefore is not as sensitive to vibrations.
Cheers, peace, love and good vibrations,
Torsten
