Quote:
Originally Posted by MBTC
Actually Access touts it as a USB 2.0 compatible device that runs at 12Mbit data transfer rate, and that is the max data rate of USB 1.1 (a.k.a Full Speed mode, as opposed to Hi-Speed mode that USB 2.0 is capable of).
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It's certainly confusing isn't it. Given that USB 2.0 is mainly available in two different chipsets - Full Speed (12Mbps) and High Speed (>480Mbps) - and that a USB 2.0 device with a Full Speed chipset cannot use the High Speed standard (due to requiring a different chipset), what in fact is the difference between USB 1.1 Full Speed and USB 2.0 Full Speed?
Both state they use the same bandwidth of 12Mbps and other similar specs. I wonder if the 2.0 standard added any additional back-end enhancements over 1.1 - such as hardware improvements, the way the data is handled, or error-correction or similar. I understand USB 1.1 fixed many problems that were present in the earlier 1.0.
As a layman, given that Access allow for 3 stereo audio outputs (6 mono outputs) at 16-bit 44.1KHz to be sent over USB...
44100 (sample rate) x 16 (bit depth) x 6 (discrete audio [mono] channels) = requires a bandwidth of 4,233,600 bits/second.
Tidying up, that's 4,233,600 / 1024 / 1024 = 4.0 Mbit/second.
I don't pretend to know much about how USB handles data, whether it is possible to use all the stated bandwidth available (12Mbps in the VirusTI case), but 4Mbits/s is well within the 12Mbit/s Full Speed standard of 1.1 and USB 2.0. In fact it still leaves 8Mbit/s available for Virus Control, MIDI bandwidth, error correction and anything else. On paper, at least, 12Mbps looks like it should be more than enough for the TI's current feature set.
If you started requiring multi-channel 96KHz @ 24-bit, that's a different kettle of fish, new hardware is required (USB 2.0 High Speed or USB 3). Virus TI mk3 material.