[LAU] Recommended USB interface with 2 XLR inputs?

[david]

Thomas Vecchione wrote:
> As was already mentioned before, USB spec is far less than the power
> needed to power a laptop hard drive.  Many USB implementation break
> this spec and provide more power, but just because a hard drive
> doesn't work, doesn't mean a USB port doesn't provide power.  The only
> type of HD that MIGHT be able to work under USB spec, and I would want
> to check this, is a SSD.

My experience with notebook hard drives in external cases is they almost 
all work without either an external power supply or using 2 USB 
connections (2nd for additional power). I have 2 notebook hard drives 
here in external USB cases, and they both have worked fine on three 
Toshiba notebooks here (all low-end Toshibas), modern and very old Dell 
business laptops, Asus netbooks, a very old IBM Thinkpad, and HP/Compaq 
notebooks.

The older of the 2 external cases didn't cooperate with a 
decidedly-high-end Sony Vaio notebook; that required using the 2nd USB 
connection for extra power.

Since I was having trouble with the older external case mentioned above, 
I contacted the vendor. They pointed out that the drive controller 
circuitry draws power, in addition to whatever power the drive inside 
pulls. Apparently the circuitry in that older case was drawing just 
enough more to take power consumption over the limit and the notebook's 
USB power protection would shut off power to the device trying to draw 
too much power.

I can recommend Nextech's NX2 external USB drive housing, works 
beautifully and currently holds a Toshiba 60GB 7200RPM notebook hard 
drive. While it includes a 2-connector USB cable (2nd one just brings in 
USB power connection), I've never needed to use it.

I don't know what the impact of laptop power management might have on 
supplying current to USB ports when running on battery.

-- 
David
gnome at hawaii.rr.com
authenticity, honesty, community