Whats the quietest way to power multiple effects in one box

[guilds100]

I'm building these effects in the same box (dyna comp, purple plexi, cot, lpb, and sho) and I'm looking for the best way to power them off 1 power input. I built a sho and dist+ in the same box before and got a bunch of noise from a single 9 volt adapter. Ive seen the ggg regulated power supply schematic and it looks promising, but I have no experence with it. Does adding a 9 volt regulator help keep down the noise? Any help would be appreciated.

[kato]

Might be easiest to buy a higher current, regulated power supply like the snake power 9d120 which puts out 500mA. You might even get off with the 300mA of the Planet Waves adapter.

[reveal]

maybe build and test with a battery first.  That will make sure there isn't something generating noise besides the power adapter.   With that many gain devices in one area, there is a chance for noise to creep from one section to the other.  If you thought the problem was the power supply you'd go nuts trying to find it.   Consider GGG's ultra clean power supply.  Its more parts but with that much invested already it might be worth it.

[Jdansti]

I'm building these effects in the same box (dyna comp, purple plexi, cot, lpb, and sho) and I'm looking for the best way to power them off 1 power input. I built a sho and dist+ in the same box before and got a bunch of noise from a single 9 volt adapter. Ive seen the ggg regulated power supply schematic and it looks promising, but I have no experence with it. Does adding a 9 volt regulator help keep down the noise? Any help would be appreciated.

I'm not the expert on this, but here's what I've learned from others on the forum. A regulator would help reduce noise, but your incoming voltage needs to be at least 3V above the regulated voltage. If you have a 12V supply, you could regulate it at 9V. If you would have to purchase a 12V or higher supply, you could just as well purchase a clean 9V supply. A lot of people like the 1Spot PS (http://www.visualsound.net/index.php/products/pedal_power_supplies/1_spot_power_supply).   I've had good success with the Danelectro DA-1 (http://www.danelectro.com/more_da1.html).  I'm not familiar with the Planet Waves PS that Kato mentioned, but it might do the job as well.

You would want to also keep your wire lengths to a minimum and use star grounding. I've read that using shielded wire on gain pots can help reduce noise.

[R.G.]

All wires are really resistors, and any current through them causes a voltage drop.

For low wiring-induced noise, you have to
1. think about where the *current* is flowing, both signal and power currents
2. minimize the area of loops of wire, as in the loop of power supply -> wire to effect -> through the effect -> wire back to power supply for all loops
3. keep wires with low signal voltages on them and high gain after them away from other wires; this can be by distance or shielding.

[guilds100]

Thanks for the replies.

I do have a 1spot that I'll try first to see if that gives me the desired results.

reveal
Do you happen to have a copy of the ggg ultra clean power supply schematic? I looked at their site and the circuit board is discontinued so they took down the schematic.

I'll definately watch my wiring and try to keep signal and power wires away from each other.

[Jdansti]

+1 RG

I don't have any info on the GGG PS, but I don't think you have to do anything exotic. The right capacitors before and after the regulator should be adequate. Here's a good article on power supplies that includes some schematics.

http://www.geofex.com/Article_Folders/Spyder/spyder.htm

Here's one that's a little more involved using an adjustable regulator LM317 and fixed resistors to regulate at 9V.  It also includes diodes to protect the regulator. You won't need the transformer or rectifier diodes if you're starting off with a DC supply. Just remember that the input voltage to the regulator has to be about 3V above the desired output voltage.

[guilds100]

+1 RG

I don't have any info on the GGG PS, but I don't think you have to do anything exotic. The right capacitors before and after the regulator should be adequate. Here's a good article on power supplies that includes some schematics.

http://www.geofex.com/Article_Folders/Spyder/spyder.htm

Here's one that's a little more involved using an adjustable regulator LM317 and fixed resistors to regulate at 9V.  It also includes diodes to protect the regulator. You won't need the transformer or rectifier diodes if you're starting off with a DC supply. Just remember that the input voltage to the regulator has to be about 3V above the desired output voltage.

I have a couple of the spyder transformers that I bought awhile ago for a project that I havent started yet. Unfortunately their too big to go into the enclosure I have for this project. I had the lm317 schematic awhile ago and forgot all about it. That may be the way to go, although those unique values for the resistors will require an order from mouser. I'll have to check and see if I have some low value trimmers that I can dial in to get the voltage out im after.

[Jdansti]

I'm not sure why they spit R1 and R2 into two resistors each. R1a and R1b are in parallel and they make 240 ohms.  R2a and R2b together make 1.5k. Maybe there's some reason for this. I use the following schematic from the data sheet and it works well.



I get 25VAC wall warts at a local surplus electronics store really cheap and use them for my AC power. That way I don't have to put a transformer in the enclosure. I label the plugs of all of my wall warts to help avoid frying something.

[reveal]

The schematic by Rick Barker posted by Jdansti is the GGG Ultra-clean schematic. The link for all the GGG data is:

http://www.generalguitargadgets.com/projects/24-power-supplies/134-ultra-clean-power-supply

The two resisters in parallel are so you don't have to order a funky value.  A trim pot would be fine, some folks don't like using a more expensive part when two common (i.e.  ones your more likely to have) resisters in parallel would do the trick. 

The schematic Jdansti posted should be fine. 

[R.G.]

As a personal quirk, the name "Ultra-clean" has always bothered me. It's OK, just not 'ultra'. It's what you get when you use an LM317 with a bypass cap on the adjust pin.

It has a little less current noise and a little better ripple rejection than an LM317 without the bypass cap, but that's all.

Sorry. I think 'ultra' was a little exaggerated on that one. I'll be quiet now. 

[tempus]

I don't own a 1spot, but I can't imagine you're going to be able to build a better supply than that, and since you've already got 1, I would just use it. It should easily power 4 effects.

I agree RG - I always thought it should be named "plenty clean enough for fx pedals" power supply, rather than"ultra clean". It's a good and sound design, and I've used a similar design for my mic pres (which are super quiet), but I've seen designs that would be far cleaner than this one. We just don't need them that clean so there's no need to bother.

[Colonel Angus]

As a personal quirk, the name "Ultra-clean" has always bothered me. It's OK, just not 'ultra'. It's what you get when you use an LM317 with a bypass cap on the adjust pin.

It has a little less current noise and a little better ripple rejection than an LM317 without the bypass cap, but that's all.

Sorry. I think 'ultra' was a little exaggerated on that one. I'll be quiet now. 

Ultra Quiet? 

@tempus - could you link me a micpre design? That is the lofty concept that got me started DIYSBing, I think I'm ready to start at least planning a project.

/hijack

[R.G.]

Don't get me wrong - it's not a bad design. I just get antsy around using superlatives like that.

That probably means I don't have future career in either mainline advertising or hifi audio sales. 

[tempus]

Don't worry RG - honesty is a desirable quality.

Anyway, every idiot knows you can't get decent noise performance, or even sound for that matter, without one of these:

http://www.essentialsound.com/essence-power-cord/

[Jdansti]

Don't worry RG - honesty is a desirable quality.

Anyway, every idiot knows you can't get decent noise performance, or even sound for that matter, without one of these:

http://www.essentialsound.com/essence-power-cord/

For only $2,000 you too can have a superduper state of the art power cord connected to the crappy wiring in the walls!

[earthtonesaudio]

The utility company looked at me funny when I tried to replace their HV step down transformer with a hifi one.

[Earthscum]

That probably means I don't have future career in either mainline advertising or hifi audio sales. 

If I ever had a big company, I'd most definitely hire someone like you to do ad write-ups!
Jokingly, "They Live!" could be a commentary about the Graphic Design/Advertising industry (my experienced opinion). 

[tempus]

It's really funny when you go to the demo page and you get to hear back to back A/B comparisons, and there is in fact no difference in sound.

[StarGeezers]

  I made one of these , works a treat , dead quiet ... I gig with it ...