Power Supplies for Benjolin (or Zeitgeist)

zynthetix

Hey all,

I saw enough questions about this going on in the main Benjolin thread that I decided to fork the topic.

Please share what you're using as a power supply for you Benjolin, Zeitgeist, or both as an alternative to the 9 volt batteries. It'd be great if we included where we got them from and the cost as well.

zynthetix · Posted: Sat Nov 14, 2009 8:52 am Post subject:

I'm quoting relevant posts from the previous thread here...

SteveBull · Joined: Nov 14, 2009 Posts: 3 Location: New York CIty

I just received a 25W AC - DC Triple Output desktop power supply from Jameco. http://www.jameco.com/ made by MEAN WELL, Model: P25A13D-R1B. Data sheet at https://www.jameco.com/Jameco/Products/ProdDS/190960.pdf. I intend to power both my Benjolin and Zeitgeist from this AC-DC supply. I also ordered the 5 pin female DIN connector from Jameco-- take a look at either Jameco part number 15844 or 29399. They were cheap enough that I ordered one of each to have a choice for the final install. At this writing Jameco has more of these power supplies in stock and Jameco prices are the lowest, and shipping w/in USA is good.

Below I cut-n-paste as email (Nov 8, 2009) from Rob to myself and others which talks about power supplies:

Hi all,

My recommendations for a power supply for both the Benjolin and the
Zeitgeist.

Principally I do always recommend a desktop Plug-In AC Adapter power supply similar in looks to the ones used for laptops. These are the safest devices to use in terms of hazard of electrical shock. Regrettably they are a bit hard to find. But note that if you want to do circuit bending experiments,
especially when they involve body contacts, then *always* use batteries!

A good choice for a desktop power supply is one that is sold by Mouser.com:
http://www2.mouser.com/ProductDetail/Mean-Well/P50A13D-R1B/?qs=sGAEpiMZZMtpkqKkT5w3uiB%2fqpDJDtRebgXKIecL%2f1U%3d

(Regrettably it seems to be a non-stocked item and might have a delivery
time of perhaps up to ten weeks.)

A simple 5-pole female DIN connector can be used on the enclosure of a
project to connect to this power supply. By using two female connectors on
the back of every enclosure one can daisy chain the power to perhaps five to
ten more boxes. Desktop power supplies are the easiest to share amongst
several projects, which is a definitive additional value.

When putting a power supply into the housing of a specific project I would
recommend a closed frame power supply like:
http://www2.mouser.com/ProductDetail/Mean-Well/T-40B/?qs=sGAEpiMZZMu0oxGuRuNKHzvx70GkCU%252bvmzt/DvjUqMo=

This is also a very good alternative to a desktop supply when putting this
supply into its own plastic housing with several connectors to power several
projects at once, thus turning it into a desktop power supply all by itself.
Probably this power supply is the easiest available one, and so you might
consider it if you do not succeed to find a suitable desktop power supply.

In essence it would be possible to use a frameless power supply like:
http://www2.mouser.com/ProductDetail/Mean-Well/PD-2512/?qs=sGAEpiMZZMu0oxGuRuNKHzvx70GkCU%252bv%252bAeyeoSWfsA%3d

but I do *not* recommend an open frame power supply for ány DIY project,
simply as the maybe twenty bucks extra that you pay for a closed frame
supply or thirtyfive bucks extra for a desktop power supply are peanuts when
at a moment in the future it does actually protect you from electrical shock
and saves your life! Néver take any risk with AC power!!!

Regards,
/Rob

Rob · Posted: Sat Nov 14, 2009 2:14 pm Post subject:

The Meanwell P25A13D-R1B external PSU is my personal first choice.
http://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?langId=-1&storeId=10001&catalogId=10001&productId=190960
The P50A13D-R1B can give more power if you need to run several boxes on the same supply. Both adapters have very good short circuit protection, if too much current is drawn they neatly shut off completely.
Additionally, in the EU one doesn't have CE issues when using an external desktop supply.
Only possible disadvantage of these adapters is that they use the same DIN plug as a MIDI connection, which might cause confusion on a box that also has MIDI in and outputs.

The Meanwell T40B is a perfect choice to build into a small to medium sized cabinet. Note that this one spreads its available power over the outputs used, so when +5V is not used the +/-12V outputs can source more current.

With switching power supplies one has the advantage of being able to use them all over the world. But analog audio circuitry needs extra analog regulators like 78Lxx and 79Lxx on the PCBs to smooth out the slight high frequency noise from the switching supply.

On bigger systems I use +/-9V regulators on each board/module. I often combine analog circuitry with CMOS (the max 20V type) and with the +/-9V I can run the CMOS on 18V, so I don't have to use voltage translation circuitry all the time between the CMOS and analog stuff. This also eliminates any crosstalk between modules over the power supply lines. With a T40B I can easily power like eight to ten analog modules. (And my modules are a bit more complex than usual.)

SteveBull · Joined: Nov 14, 2009 Posts: 3 Location: New York CIty

I put +12VDC to the 9VDC header on the Zeitgeist and the green power LED glowed yellow very bright so that I was immediately alarmed and unplugged the power. In the NYC:Harvestworks November 2009 workshop there were some questions about the quality of one of the chips provided with the Zeitgeist kit.

Has anyone had a chance to put that chip to the test on oscilloscope?

What is a good procedure and steps to follow when I try and power up the Zeitgeist the next time?

OmbientMike · Joined: Nov 20, 2005 Posts: 17 Location: NJ