Jump to content
Why become a member? ×

Power Supplies


cheddatom
 Share

Recommended Posts

a lot of people seem to be going to isolated PSUs at the moment, rather than a huge daisy chain. I was once told that I'd get less noise if all of my pedals had a "common ground". Would that have anything to do with whether they're isolated?

I always run mine off daisy chains from a Golyke Powerall and/or a Diago Powerstation. If I have some serious dirt/fuzz going on then I get a lot of noise, but if I don't, I don't.

I just thought it'd be good to get general thread going about PSUs as I'm sure there are some experts here.

Link to comment
Share on other sites

I've been using a 3000mA PSU with a daisychain for 8 FX to power my pedalboard wich has: Korg Pitchblack - MXR Bass Octave Deluxe - Darkglass B3K - 3Leaf Groove Regulator - EBS Multicomp

It's been used regularly for the past 7 or 8 years and i only get noise when i kick in the b3k. Fortunetly the sheer wall of OD/Fuzz produced by the b3k is enough to get by without bleeding that noise/hiss/feedback to the audience. I'm sure that if would use a separate PSU for the b3k the noise would lower or even disapear but i don't want to lug the extra stuff unless it's an outdoor gig with hired PA company where everything needs to go smooth and without noise. For pubs and given that i only use OD in a couple of songs the daisychain will keep being used.

Having 3A i've used it to hook up multi-fx boards at the same time as my pedalboard and even the guitarrists pedals along mine during rehearsalls. Never missed a bit.

BTW, my PSU was bought from effectpowersupplies.co.uk a long time ago before they changed their name to fxpedal.co.uk. Now they have diferent producs and maybe some of them will address this issue. I'll know about that in another 8 to 10 years when my PSU finally breaks down and i'll need to buy another.

  • Like 1
Link to comment
Share on other sites

I'm the same as you - have run 14 pedals from a Diago Powerstation for years with no issues. I get the science of isolated outputs and everything, but daisy chaining has never caused me any issues and it takes up next to no room on the board, especially compared to the current crop of PSUs everyone seems to be using.

Link to comment
Share on other sites

I definitely noticed a huge difference when I changed to my MXR ISO brick. My signal chain of: Dunlop mini volume pedal, boss OC2, boss PS5, dark glass duality, iron ether frantabit, soundblox envelope filter, tc electronic sky surfer reverb, tc electronic nova repeater, Aguilar tone hammer, and ditto. Given the fact that the tone hammer needs 18V, and all the other pedals take different current draws, the mxr not only eliminated some ground hum I was getting, I also got better results from each of my pedals because they were actually getting exactly the current they needed. I can't recommend a good psu highly enough

Link to comment
Share on other sites

[quote name='Ghost_Bass' timestamp='1497458708' post='3318367']
... i only get noise when i kick in the b3k... I'm sure that if would use a separate PSU for the b3k the noise would lower or even disapear
[/quote]

I would expect that as it's a dirt pedal, I'm not sure why you'd expect it to disappear with a different PSU?

Has anyone got a handy link to explain this to me? It's just that someone once told me daisy chaining would be "cleaner" but now everyone's going isolated... I haven't got a clue on the science of it

Link to comment
Share on other sites

[quote name='cheddatom' timestamp='1497514943' post='3318724']
Has anyone got a handy link to explain this to me? It's just that someone once told me daisy chaining would be "cleaner" but now everyone's going isolated... I haven't got a clue on the science of it
[/quote]

Don't have a link but my input:

As with most things there's a few things going on at the same time -

'Digital Noise' - as lots of people find - a digital unit may put a lot of noise onto the Ground Power line which is then connected to other fx in the daisy chain - so an isolated psu helps here.
Bear in mind that 'Ground' is never the same at any two points carrying a current since cables have resistance and inductance ( unless you had superconductors !)

'Ground Loops' - assuming all inputs / outputs are unbalanced then with any daisy chain you have 'ground loops' which are susceptible to external interference. Susceptibility depends on cable layout etc. It may cause you a problem or it may not but it's always there waiting to !

Link to comment
Share on other sites

You can run a ton of effects daisy chained without trouble. But then you get effects that are digital clocked DSP units that create a ton of power supply noise, daisy chain to those and you will get high pitched buzzing or whining noise, whether they are in the signal path or not, as they put noise down the power supply.

My first one of these was the Fishman powerchord FX, but then also the Zoom B3. If you have one of those, your options are an isolated power supply or a separate power supply for them.

If you don't have one of those, you won't have that issue, and you don't need to think about an isolated power supply. If you do have one of those, you don't really have an option!

Link to comment
Share on other sites

[quote name='cheddatom' timestamp='1497518897' post='3318779']
OK, that's fairly simple, so any digital pedals will introduce noise if they're on a daisy chain, but if they're on an isolated supply, or their own separate supply, they won't

...I should probably get an isolated supply then! :)
[/quote]

Not necessarily any digital pedals, just many digital pedals.
What I mean is that if you have the problem caused by digital pedals, you KNOW you have the problem!

Link to comment
Share on other sites

I'm pretty sure I have experienced that before. I assumed I was getting the noise as I was drawing too much current for the supply, although the numbers seemed OK

but in general, are there are plus-points to a daisy chain? Would it be possible to reduce noise in a particular chain by switching from isolated/separate supplies to one supply with a daisy chain? Obviously disregarding digital pedals there. Or is it best practise to always have isolated/separate supplies?

I suppose the question is: If money were no object, would you want an isolated supply for each pedal? Or would there be occasions where a daisy chain is preferable?

Link to comment
Share on other sites

I ran a daisy chain for years without an issue, apart from introducing chirping and whining noises into the signal with the odd (but not every) digital pedal.

I started practicing through a headphone amp where I noticed the noise in my chain a lot more (my cabs don't have tweeters). Since I'd recently added 12V and 18V pedals to the collection, I bought a Cioks DC5 to power and isolate them all. Yet the noise remained.

In the end after extensive testing, I found it was the recently added EBS flat patch cables that were adding a ton of noise if I had my dimmer switch on in the room. I now have silence after switching those out!

Edited by dannybuoy
Link to comment
Share on other sites

[quote name='cheddatom' timestamp='1497524259' post='3318829']
I suppose the question is: If money were no object, would you want an isolated supply for each pedal? Or would there be occasions where a daisy chain is preferable?
[/quote]

If money were no object I would just do what worked. In my case, money really isn't an object when it comes to what I have, I have the isolated supply I have now as it works and it is easy, so it will stay until there is a problem. I cant stand having extra noise, but I am also not going for hifi down the dog and duck.

Link to comment
Share on other sites

[quote name='Woodinblack' timestamp='1497538557' post='3318972']
If money were no object I would just do what worked. In my case, money really isn't an object when it comes to what I have, I have the isolated supply I have now as it works and it is easy, so it will stay until there is a problem. I cant stand having extra noise, but I am also not going for hifi down the dog and duck.
[/quote]

right but you'd up your game for the Tickled Trout I'm sure! :)

What got me thinking is that a guy who came across as an "expert" told me ages ago that the noise on my pedalboard was all due to grounding problems, and that he would make me a power supply to give all the pedals a "common ground". He never did it, and I never really understood what he was on about, but once I got a decent supply my noise problems disappeared and I never thought about it again until the recent spate of posts about isolated supplies

Link to comment
Share on other sites

[quote name='cheddatom' timestamp='1497540605' post='3318982']
right but you'd up your game for the Tickled Trout I'm sure! :)

What got me thinking is that a guy who came across as an "expert" told me ages ago that the noise on my pedalboard was all due to grounding problems, and that he would make me a power supply to give all the pedals a "common ground". He never did it, and I never really understood what he was on about, but once I got a decent supply my noise problems disappeared and I never thought about it again until the recent spate of posts about isolated supplies
[/quote]

The guy was 'partly right', but it's knowing where that common ground is. I can understand where he is coming from when looking at a basic schematic diagram. The ones in some of my old books always have a single line at the bottom for 0v and thus it's easy to assume that it is the only and common ground path. For DC, fine. However, it doesn't take in to account the path the AC (audio and noise) signal goes on when using patch cables and other leads. So, you have a 'ground' going down the cables and then, when you start using a daisy chain power supply, well, that's another ground path. Two paths, which is where the problems can appear. I'll quickly insert that some pedals really aren't bothered and you might not ever have any noticeable noise problems from them when daisy chained together, but certainly some, like a pair of mine that both use a fair amount of DSP do seem to dump (AC) noise on to the daisy chained power supply output. This is where isolated power supplies come in. A daisy chain power supply only has one '+' and one '-' for supplying all pedals. The isolated supply 'decouples' so each pedal sees a completely independent power source, breaking the 'common shared' '+' and '-' connections - which would be the equivalent of using multiple adaptors plugged in to a long trailing socket blah blah, nobody likes that. A singe box that can mimic separate power supplies is tidier and far less hassle.

After a long day working, I hope this makes sense!

Edited by dood
Link to comment
Share on other sites

There are different ways of creating an isolated power supply. Just a few examples using my limited understanding:

1. Literally the equivalent of having a bunch of wall warts in one box. Each power supply is completely independent. If they have a mains transformer in the design to drop the mains voltage down from 240v to say 12v, then each has it's own.
2. The same, but there is one mains transformer, but the transformer has multiple parallel windings on it's output side (Secondary) each supplying individual circuits that feed separate outputs.
3. Some clever stuff that I haven't had time to study yet, often involving Switch Mode Power Supplies (Not using mains transformers). Cheap, reliable and sometimes a good choice if nearby pedals are prone to electromagnetic interference.

Edited by dood
Link to comment
Share on other sites

[quote name='cheddatom' timestamp='1497524259' post='3318829']

but in general, are there are plus-points to a daisy chain? Would it be possible to reduce noise in a particular chain by switching from isolated/separate supplies to one supply with a daisy chain? Obviously disregarding digital pedals there. Or is it best practise to always have isolated/separate supplies?

I suppose the question is: If money were no object, would you want an isolated supply for each pedal? Or would there be occasions where a daisy chain is preferable?
[/quote]

Technically Isolated supplies are always better. Basically you have a 'Ground' connection via the patch cable screen. Ideally you don't want another common connection path to 'ground'.

Link to comment
Share on other sites

[quote name='dannybuoy' timestamp='1497524385' post='3318830']
I ran a daisy chain for years without an issue, apart from introducing chirping and whining noises into the signal with the odd (but not every) digital pedal.

I started practicing through a headphone amp where I noticed the noise in my chain a lot more (my cabs don't have tweeters). Since I'd recently added 12V and 18V pedals to the collection, I bought a Cioks DC5 to power and isolate them all. Yet the noise remained.

In the end after extensive testing, I found it was the recently added EBS flat patch cables that were adding a ton of noise if I had my dimmer switch on in the room. I now have silence after switching those out!
[/quote]

Yes - I've had a similar problem with those generic cheap moulded patch cables in the different colours. Noise picked up at the jack ends. Replacing with good metal jack patch cables cured it.

Link to comment
Share on other sites

[quote name='dood' timestamp='1497541674' post='3318992']
The guy was 'partly right', but it's knowing where that common ground is. I can understand where he is coming from when looking at a basic schematic diagram. The ones in some of my old books always have a single line at the bottom for 0v and thus it's easy to assume that it is the only and common ground path. For DC, fine. However, it doesn't take in to account the path the AC (audio and noise) signal goes on when using patch cables and other leads. So, you have a 'ground' going down the cables and then, when you start using a daisy chain power supply, well, that's another ground path. Two paths, which is where the problems can appear. I'll quickly insert that some pedals really aren't bothered and you might not ever have any noticeable noise problems from them when daisy chained together, but certainly some, like a pair of mine that both use a fair amount of DSP do seem to dump (AC) noise on to the daisy chained power supply output. This is where isolated power supplies come in. A daisy chain power supply only has one '+' and one '-' for supplying all pedals. The isolated supply 'decouples' so each pedal sees a completely independent power source, breaking the 'common shared' '+' and '-' connections - which would be the equivalent of using multiple adaptors plugged in to a long trailing socket blah blah, nobody likes that. A singe box that can mimic separate power supplies is tidier and far less hassle.

After a long day working, I hope this makes sense!
[/quote]

It makes sense :-)
I'd just add in that regarding picking up external interference ( as opposed to noise from digital pedals ) then the pedals themselves make little / no difference. It's the cable layout an the area of the 'ground loop that matters. The external interference induces a voltage into the loop.
Minimising the loop area will reduce the effect. As will increasing distance from interference source.

Link to comment
Share on other sites

[quote name='rmorris' timestamp='1497602059' post='3319342']


Yes - I've had a similar problem with those generic cheap moulded patch cables in the different colours. Noise picked up at the jack ends. Replacing with good metal jack patch cables cured it.
[/quote]

Yup, the only other cables that had the same issue were the Warwick Rockbass clones of the EBS flat ones and a cheap plastic Bespeco one. Planet Waves plastic jacks were fine though, as were anything metal, from cheapos to pancake jacks, to George L's.

Link to comment
Share on other sites

[quote name='dannybuoy' timestamp='1497708889' post='3320177']
Yup, the only other cables that had the same issue were the Warwick Rockbass clones of the EBS flat ones and a cheap plastic Bespeco one. Planet Waves plastic jacks were fine though, as were anything metal, from cheapos to pancake jacks, to George L's.
[/quote]

Yes - I haven't cut one open but I assume that the problem cables don't have screening at the plug end whereas if there's effective screening beneath the overmoulded PVC then that's all good.

Link to comment
Share on other sites

  • 4 weeks later...

[quote name='ambient' timestamp='1499876541' post='3334272']
I'm looking for a new/better power supply.

Which is the best one?
[/quote]

That depends on size/budget constraints and what you need to power?

If you want cheap, and zero footprint on the board, only have 9v pedals, and no awkward pedals that need isolation - One Spot

Something isolated, flexible 9/12/18v that fits under a PT Nano - Cioks DC5

A monster that will power everything under the sun - Truetone CS-12

Bargain isolated supply - Fame/Vitoos DC8

Link to comment
Share on other sites

[quote name='ambient' timestamp='1499876541' post='3334272']
I'm looking for a new/better power supply.

Which is the best one?
[/quote]

[quote name='dannybuoy' timestamp='1499886440' post='3334354']


That depends on size/budget constraints and what you need to power?

If you want cheap, and zero footprint on the board, only have 9v pedals, and no awkward pedals that need isolation - One Spot

Something isolated, flexible 9/12/18v that fits under a PT Nano - Cioks DC5

A monster that will power everything under the sun - Truetone CS-12

Bargain isolated supply - Fame/Vitoos DC8
[/quote]

There's also the gigrig system. Pricey, but versitile and expandable.
If 5amp is a bit much for you, you can get a 1spot and use the gigrig isolator/adapters with that. That way you can move up to the gigrig generator if you up size your board.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...