The No.1 Website for Pro Audio
 Search This Thread  Search This Forum  Search Reviews  Search Gear Database  Search Gear for sale  Search Gearslutz Go Advanced
Pedalboard power, regulators, etc. Utility Software
Old 19th September 2014
  #1
Gear interested
 

Thread Starter
Pedalboard power, regulators, etc.

I am building an Ableton Live pedalboard, and am going to stick an Intel NUC i5 (4"x4"), RME FireFace UCX, Ableton Push, and a bunch of pedals on my pedalboard and power them all from the same 12V power supply. If I get a 12V 20A power supply like this one:

12V 20A 240W Switching Switch Power Supply Driver for LED Strip Light 110V 220V | eBay

can I power my 9v 200ma-300ma pedals by just using a single 3A 9V voltage regulator? And the same for the 5V 1A Ableton Push controller? And while the Intel PC power supply is 19V 10A, and the manual says it can run at 12-19V, is there any benefit to using a 200W 12V-19V step-up booster or should I just run the 12V dc into it? I assume there is nothing to do about the 18v AC mixer?

Here are the components and their power req's:

18v AC 500ma - Alto Mixer
12v 3A - USB Hub
12-19v 10A (19v wart) - Intel NCU
12V 2A - RME
12-18v (15v wart) 400ma - Eden
9v 300ma (120v direct) - FCB
9v 200ma - POG 2
5v 1A - Ableton Push


Thanks!
Old 20th September 2014
  #2
Lives for gear
 

Just to respond to your question a little bit; not many people - not even pro's - would invest the time or trouble it would take to do here what you want done - it's not worth it. Obviously it CAN be done, but it's not sensible. The big question is who would even do the design work, as well as the physical work?
Old 20th September 2014
  #3
Lives for gear
 
Richard Crowley's Avatar
No, there is no reason to go to any extra steps to create 19V for the NUC. 12V is plenty as all the internal voltages are much lower.
They only used 19V because that is the most common computer supply voltage. I work there and I asked them that exact question.

I would certainly confirm that those little pedal gadgets all use negative ground. I don't play guitar/bass, but I have heard horror stories about positive ground.
But assuming common negative ground, those little 3-terminal regulators are an ideal solution to create all the lower voltages.
Remember to use the prescribed capacitors to stabilize them.

I am assuming that power supply is either quiet enough, or that you can add extra filtering in case it isn't. Shouldn't be a major issue.
Power supplies that are advertised for "LED strip lights" sometimes concern me that they may not be as quiet as those made for audio, etc.

As you say, the only exception is that requirement for 18VAC for the mixer. But that isn't a show-stopper.

I say go for it. You won't be the first (or last) person to make something like this.
There have always been people who construct things like this since the first days of electronics.
And there is a huge and growing "maker" community these days. I feel sorry for people who are limited to buying things off the shelf.
Old 20th September 2014
  #4
Gear interested
 

Thread Starter
Quote:
Originally Posted by Richard Crowley View Post
No, there is no reason to go to any extra steps to create 19V for the NUC. 12V is plenty as all the internal voltages are much lower.
They only used 19V because that is the most common computer supply voltage. I work there and I asked them that exact question.

I would certainly confirm that those little pedal gadgets all use negative ground. I don't play guitar/bass, but I have heard horror stories about positive ground.
But assuming common negative ground, those little 3-terminal regulators are an ideal solution to create all the lower voltages.
Remember to use the prescribed capacitors to stabilize them.

I am assuming that power supply is either quiet enough, or that you can add extra filtering in case it isn't. Shouldn't be a major issue.
Power supplies that are advertised for "LED strip lights" sometimes concern me that they may not be as quiet as those made for audio, etc.

As you say, the only exception is that requirement for 18VAC for the mixer. But that isn't a show-stopper.

I say go for it. You won't be the first (or last) person to make something like this.
There have always been people who construct things like this since the first days of electronics.
And there is a huge and growing "maker" community these days. I feel sorry for people who are limited to buying things off the shelf.

Richard, thanks for the info on Intel, negative ground, capacitors, and filtering. Those details are exactly the reason I asked here.

Would you mind giving a little more info on the capacitors and filtering bits? What is "prescribed"? I'm not as familiar with that.

Honestly I'm surprised no one has done this before in the Ableton world. It's so cumbersome to have a laptop on stage as a musician and the screen there introduces a headspace that most of the time should not exist on stage. I've done quite a bit of work like this in the past for other systems, for example rigging up a PC in my Vanagon with a 12V power supply back before iPods and seemingly infinite time building electric RC cars when I was a kid, but never for audio.
Old 20th September 2014
  #5
Gear interested
 

Thread Starter
Richard, I am seeing the capacitors described in the voltage regulator data sheets. Now just to learn about power filtering to reduce noise for audio...
Old 20th September 2014
  #6
Lives for gear
 
Richard Crowley's Avatar
Yes, the data sheets are the prime source of information for deploying those parts in the Real World.
The capacitors aren't large or expensive, but very important to keep the circuit stable.

We don't know if you need any extra filtering until you actually try it.
But at least allow the possibility of some local decoupling between loads (series resistor, filter cap, etc.)
Old 20th September 2014
  #7
Lives for gear
 
S2udio's Avatar
 

Quote:
Originally Posted by Richard Crowley View Post
I say go for it. You won't be the first (or last) person to make something like this.
There have always been people who construct things like this since the first days of electronics.
Old 21st September 2014
  #8
Gear interested
 

Thread Starter
I learned that the capacitors ARE the power filtering, and the best place to do that is on each of the voltage-regulated circuits separately.

Very cool stuff. This project has lots of other fun little problems to solve as well, like how to safely shut the PC down when I kill the power to the board using the AC switch I'll install on the power supply.
Old 21st September 2014
  #9
Lives for gear
 
Richard Crowley's Avatar
Quote:
Originally Posted by patrickkidd View Post
I learned that the capacitors ARE the power filtering,
Not exactly. The small capacitors at the 3-terminal regulators are there to prevent the regulators from breaking into destructive oscillation (what we would call "feedback" in the audio world) There are a small size (capacitance value) because they "short out" high frequencies that could cause the regulators to become unstable.

But filtering noise, especially mains-frequency (50Hz-60Hz) requires rather larger capacitors because they must be effective down to 20 Hz.

Noise filtering and decoupling are ADDITIONAL and DIFFERENT requirements than stabilization of the regulator chips. Until you actually rig everything up, you won't know whether additional noise filtering and/or decoupling will be required.

Quote:
and the best place to do that is on each of the voltage-regulated circuits separately..
The stabilizing capacitors must be right AT the voltage regulator pins. If they are too far away, they won't be able to stop the oscillation.

Quote:
"Bypass capacitors are recommended for optimum stability and transient response, and should be located as close as possible to the regulator."
http://www.ti.com/lit/ds/symlink/lm340-n.pdf page 14
OTOH, filtering and bypass are best close to the loads.
Old 22nd September 2014
  #10
Gear interested
 

Thread Starter
Wow, all very helpful. You are making a world of difference for me. I have been busy in other threads in other forums at Intel (https://communities.intel.com/thread/55277) and electronics.stackexchange.com (capacitor - Safely shutting down 19V mini PC when power fails - Electrical Engineering Stack Exchange) to sort out the battery supported PC shutdown sequence when I unplug the pedalboard from the wall. It's a very cool problem, with the end result of being able to forget about the fact that a PC is there and just plug / unplug the board like a 'normal' player. I initially found a shutdown controller but then had to look for a power supply switcher to switch over to battery, and ended up with OpenUPS. This definitely isn't staying cheap, but man it's a cool problem.


It appears that once I get all this stuff hooked up I could need to look at the power supply, but I guess well see when I get there.
Old 30th September 2014
  #11
Gear interested
 

Thread Starter
Well, several long nights and two fried breadboard later, I've got a working board with three voltage circuits. The PC boots up when I plug the board in and safely shuts down with OpenUPS when I unplug it. Richard, thank you so much for your advice, it really helped a lot! I'll post back with the finished product, and later a blog post with the results. PC-on-a-pedalboard is a killer idea!
Old 11th December 2014
  #12
Gear interested
 

Nuc pedalboard ups

Hi Patrick,
Curious to see if you've had any more progress with your nuc on your pedalboard. Any chance you'd be comfortable with listing all the components of your setup? I'm planning on doing the same setup, and it seems like you've got a pretty thorough design. Also, would love to hear how it's working and if you've had any issues!
Old 11th December 2014
  #13
Gear interested
 

Thread Starter
Actually, I have! Thanks for asking. I have been waiting for the right time to write a comprehensive walk-through on my blog @ pkaudio.blogspot.com. This turned out to be a massive project but one that can be replicated: Major projects:

- UPS and AC power supply
- Scripted MS Windows automation (handle dialogs, config software on USB connect, etc)
- Programming of the Max for Live / Ableton Push patch for performance
- Creating a new application for remote PC control via midi, which runs command lines and python scripts when a midi message comes through. i use it to load different Ableton Live sets, reset the knobs in the current set, reboot the virtual midi loopback driver, reboot the system, etc. All from the pedalboard.

I promise that I'll write it up (it's a hobby of mine) and when I do I will post it back to this thread, and I will include a list of all of the various forum threads that got me here.

Bottom line is that I can walk in, turn on the power, wait about 40 seconds for everything to start, and start performing.
The power cycle of the NUC is totally solid and will protect against bad power at the venue. The only caveat is that you have to wait at least 15 seconds once you have killed the power in order to turn it on again.

more soon!
Old 12th January 2015
  #14
Gear interested
 

Thread Starter
OK, here is a comprehensive writeup on the Ableton pedalboard. Have fun!

A couple of months of work and I have finished building an Ableton Pedalboard. It's an Ableton Live-Powered pedalboard that just has an on-off switch. Throw it on the stage, turn it on, play set 1, play set 2, unplug and take home. Works great!

Complete write-up is here: Ableton Pedalboard | Vedan? Media





Old 15th January 2015
  #15
Lives for gear
 

You see, I told you to go ahead and build it - what took you so long!
Old 15th January 2015
  #16
Gear interested
 

Thread Starter
Quote:
Originally Posted by Vitalis View Post
You see, I told you to go ahead and build it - what took you so long!
Haha, all the bulk of the problem solving took about a month from when I started this thread. Then the testing has been on going.

Thanks!
Old 15th January 2015
  #17
Lives for gear
 
Richard Crowley's Avatar
Good Show! Congratulations on a great project.

And 10,000 extra points for posting a great documentation of the project!
Old 15th January 2015
  #18
Gear interested
 

Thread Starter
Quote:
Originally Posted by Richard Crowley View Post
Good Show! Congratulations on a great project.

And 10,000 extra points for posting a great documentation of the project!
Thank Richard, you were particularly helpful getting me off the ground with it.
Topic:
Post Reply

Welcome to the Gearslutz Pro Audio Community!

Registration benefits include:
  • The ability to reply to and create new discussions
  • Access to members-only giveaways & competitions
  • Interact with VIP industry experts in our guest Q&As
  • Access to members-only sub forum discussions
  • Access to members-only Chat Room
  • Get INSTANT ACCESS to the world's best private pro audio Classifieds for only USD $20/year
  • Promote your eBay auctions and Reverb.com listings for free
  • Remove this message!
You need an account to post a reply. Create a username and password below and an account will be created and your post entered.


 
 
Slide to join now Processing…
Thread Tools
Search this Thread
Search this Thread:

Advanced Search
Forum Jump