Raspberry Pi hard drive

[PeteB]

I don't think it is JUST marketing, but I don't want to buy a drive which is intentionally slowed down. I can see reducing the startup current as a tradeoff with a longer ready time, but NOT spending money on something that is likely to be as slow as SAT-1 when connected to a PC.

I am going to try to fit a standard 2.5" drive into a stacked enclosure with a Pi 2, the DAC+ or DIGI+, and a GPIO expansion board (for an encoder or volume control pot). I did that on an earlier project, and it turned out ok. The stack plate outline I want to use will look something like this:

[Grundgütiger]

[PeteB]

Hi,

I saw that blog entry. I agree that in general the 500Gb "Blue" single-platter drives are the ideal choice to use on a Pi. You can't really go wrong with either choice. The reduced startup current is nice, but not really necessary with a 2A or 2.5A supply, you seem to have proven that yourself,

I measured just around 1A startup current total with either of the newer WD drives I tested - Pi 2, DAC+, WiFi dongle, wireless keyboard dongle, disk drive. Normal operating current is around 0.5A while playing music from the local hard drive, or streaming over WiFi.

Downside is that the other changes mean the data transfer rate will be very slow if you ever connect the drive to a PC USB port. Perhaps they want to make sure people do not use the discounted drives as generic USB drives (?)

P.

[Grundgütiger]

I actually think about adding another board to the Pi to handle the "power issue" (no, I'm not scared but have some spare time to play around). After some researches I think the German StromPi might be a good solution: (in German). It serves up to 3A power and is able to handle different volage. Plus you can add a battery pack to safely shut down the Pi in case of a power failure.

...

[PeteB]

[PeteB]

In the meantime, Pi, DAC+, two dongles, 1 Tb disk drive, running fine for two days, with frequent restarts... As you said, no problems when using a good supply, You can see the dongle I use to monitor current and voltage in the corner of the pic. (To make better measurements, I use a Fluke 115).

Now I just need to make a good stack enclosure to hold all of it, and leave some place for a volume control, and a filter, etc...

[johnbanks]

PeteB ...
What is the gizmo that's showing 5.11 V and 0.50 A in the photo?
Thanks

[PeteB]

[Grundgütiger]

On his YouTube channel, Hans Beekhuyzen claims that the sound of a Raspberry Pi that has a HiFiBerry Digi+ board or a HiFiBerry DAC+ board attached gets better, when those boards get their own power supply: . He also speaks for good linear power supplies.

[PeteB]

I saw his December review, not the January one, thanks.

Hans is correct, I tested my DAC+ with a bench supply, and you can hear the difference with good headphones.

You do NOT need an expensive analog supply for a DAC+ though. (Hans is a cost-is-no-object kind of guy, and he bought a top grade universal supply, we do not need that). Nor do we need an expensive transformer like the one he mentions.

Here is a link to a 25 VA, split-output transformer I used in the power supply design I refer to elsewhere, it costs $11 in single quantity, and it has double the output needed:



It is made in Asia, and quite good for audio (tested). Similar transformers are used in medical equipment costing over $10K.

A manufacturer can't put an extra $11 worth of copper and steel, not to mention and extra 0.65Kg weight into a power supply for a Pi, but you can...