What’s changing

MeeBlips will now use 9VDC power connections instead of USB. That wouldn’t normally be news, except we think you’ll find both usability changes and a difference in how your MeeBlip sounds – explanation below.

Original MeeBlips shipped with USB ports on the back for connecting to power. (It’s not a USB data connection; it’s just a power port that happens to use a USB connector.)

Why did we use USB in the first place?

Well, we thought it made a whole lot of sense. USB standards are global, so you don’t have to worry about having the right plug. The cables are lightweight, which saves money on international shipping – we work really hard to make the MeeBlip as inexpensive for you as possible.

Why did USB wind up sucking?

So, there’s theory, and then there’s practice – doh. In theory, USB power should work perfectly. But testing MeeBlip prototypes gave us little indication of how noisy most USB power is. As James writes:

Most USB wall adapters bleed quite a bit of 50/60 Hz line noise, and the USB jacks on computers are even more unpredictable.

The solution is to do heavier filtering of the power line to minimize noise – a Resistor-Capacitor filter can do a lot to filter it out, and it’s a relatively simple mod to apply to the MeeBlip main board if you have moderate soldering skills.

@charliex on the MeeBlip forums did his own fix using just this technique; you can read about it on our Noisepages group:
FIXED usb noise problem

Why 9VDC is Better

Adding 9VDC power helps us prevent suckitude. Here’s James again:

Providing a 9V wall power supply and a new daughterboard with onboard voltage regulation gives us more control over the quality of the power reaching your MeeBlip. Our power supply is a good quality regulated supply that puts out an honest 9V, rather than the 14-16V some cheaper unregulated devices put out. That reduces heat dissipation through the voltage regulator and dramatically reduces the noise floor.

We could use heavy filtering as employed in Charlie’s fix, but that can cause issues with the chip starting up in extreme cases.

I’ve got a MeeBlip already; how can I switch out the USB?

If you’re really lucky, you’ve got perfectly quiet USB power or are happy with Charlie’s fix. But if not, we’ve got inexpensive options available in our MeeBlip shop. It’s a super-easy project to swap out, and $15 gets you everything you need to do it – the pre-assembled board, plus the new overlay (so it says “9VDC” and not “USB” on the back)!

You can also buy a 9 VDC wall wart power supply that we like a whole lot for $9.

Here’s what the new power board looks like:

The resulting MeeBlip is pictured at top.

I’m thinking about getting a new MeeBlip. Will I get one with 9VDC?

All new orders will now include the 9 VDC power option. On the Quick Build kit, we’re including the new power board with 9V and not USB, and we’re even throwing in the “wall wart” power adapter. (If you’re outside North America, you’ll likely need an additional physical plug adapter.)

If you’re buying a DIY Kit, you still get a USB cable, but we now include the 9VDC power jack and voltage regulator by default.

Here are the new Quick Build kit contents:

To pick up retrofit kits (or get your MeeBlip, if you haven’t already), head over to our store page:
http://meeblip.com/get-one/

And to discuss this – or anything else – see you in the forum!
MeeBlip Group Forum