Suggestions For 9V Power Supply

[Pavlos]

Well Diago have just safety recalled my prefered powers supplies so now I need to replace them. Does anyone have any particular recomendations or favoutites, and of course any to avoid?

What I 'm looking for is something that is reliable, both physically and electrically quiet, preferably not too large and at least 1A total output. I'm happy to daisy chain off a single high output outlet, if multiple outlets then only need +9V and more the merrier.

What I've found so far at the cheaper end of the scale are the likes of 1-Spot and Mooer, otherwise it's a sizable jump to the T-Rex and Dunlop power bicks.

There is also below, the layout Mug has done on page 4 looks interesting, jut need a suitable supply, and how much current can each output supply safely?
http://guitar-fx-layouts.42897.x6.nabble.com/Custom-Voodoo-Labs-Pedal-Power-2-Plus-td8192.html

[Ciaran Haslett]

Provided you're sticking to 9V only (omitting the charge pump) you're limited by the regulators (~1A) and your input power supply (typical laptop bricks are around 5A).

Behringer ripped off the T-Rex supplies a few years ago.  I paid £22 for their Harley Benton Power Plant Junior (regulated/isolated).  Each out is limited to 100mA but it has more than enough for me (I only run 10 pedals on my board at any time and only 3 digital...2 PT2399 builds and a boss tuner). It's served me great for 3 years, whisper quiet and bolted under my Pedaltrain 2 completely out of sight.

Hard to whack for a score

[balazs.bencs]

I just got a Palmer power supply from thomann, which is great, 9v isolated outputs (5 of them), with 250mA on each output - extra feature is an overload LED, which tells you if there is a voltage drop.
I looked inside, it has a solid toroidal transformer, looking pretty great.

They have 4-5 different types of pedal PSUs, take a look: http://www.palmer-germany.com/mi/en/Power-Supplies.htm

[Pavlos]

Thanks for the replies :o)

balazs.bencs
Those Palmer power supplies look pretty good, don't really hear or see much of them over here in UK though.

Ciaran
Those Harley Benton PSU's look pretty much identical to the Chinese ones you can get with any number of different names on evilbay and amazon? Glad you've had good mileage out of it though, when their QC is working properly those Chinese factories produce some excellent stuff!


Thinking that I might have a go at the DIY route and see how I get on, though I might also end up biting the bullet and treat myself to the power brick....decisions eh!

regarding http://guitar-fx-layouts.42897.x6.nabble.com/Custom-Voodoo-Labs-Pedal-Power-2-Plus-td8192.html
Mug did an updated layout on the fourth page which loses the 18V and -9V outlets and just has 8 +9V outlets instead, which looks like it would work well for my needs.
But just to make sure I'm understaing you correctly, are the regulators capable off approximately 1A output each as long as the 12V supply has enough output ? such as 4 outlets running at maximum output would need minimum 12V 4A, and 5 outlets 12V 5A etc? I expect it would be unwise to try to run any of the regulators too close to their maximum output though, even if heatsinks are fitted and the enclosure is ventilated?

Also, as long as it can deliver enough output, does it make much difference what 12V supply is used? And would it be possible to put 2 of these boards in a single box and fed from a suitably beefy supply?

[Ciaran Haslett]

Yeah...I'm cheap lol.  But it hasn't let me down yet.  It did come with a fixed power cable however so I cut in an iec socket instead.  Tight squeeze but I prefer having a detachable power cable.

And yes....overall max current it decided by the power supply.  Max current per daisy chain is decided by a regulator.  Also yes the closer you reach to max current the warmer they will run.  Using a 15 or 20v supply will make them run hotter still.

And yes again...you can add as many as you want as long as you stick to the current limitations above.  

You'll most likely use a switched mode supply.  They tend to be noisy without adequate filtering.  If I was to build the "Super Duper Deluxe All The Bells And Whistles" power supply...I'd consider adding something like the "humminator" to each 9V outlet.  This would make it really rather big though and most likely isn't necessary.  Just speculating.

[Pavlos]

not cheap....frugal lol, one of the reasons I ended up with a couple of Diago PS10, they were only £25 each, seemed to be really well made, absolutely silent and only about a couple of inches square. Talk about miffed when I got the email through that they were being safety recalled, stiil I had a few years trouble free and should be getting a full refund. A tad inconvenient but better to be safe than sorry eh! And anyway, I wasn't building pedals back then.......so maybe mega PSU with 14000000 outputs and hooked straight into Drax Power Station

I know what you mean about captive leads, not a fan either.

I did see mention of the 15-20V supply making the regulators run hotter, makes a lot of sense, the extra volts have to go somewhere, I've got a 12V 1.2A supply in the draw anyway so that would probably do to get me off the ground, beffier PSU can always follow on,

I'd thought about the huminator as a possibility as well, and if needs be they don't take up too much room, but from what I understand from the posts, I think there might be some filtering going on already? Otherwise, would it make sense/be possible to put a huminator on the input to filter the incoming supply, or is that not a good idea?

[Travis]

I’ve never found the huminator to be super effective but it has a lot of fans

One thing to keep in mind regarding the DIY project is that the outputs are not isolated from each other because they share a common ground. If you need truly isolated outputs, you could start with a transformer like this

http://www.smallbear-electronics.mybigcommerce.com/transformer-power-for-pedal-boards/

This transformer is made by/for Weber speakers and can be purchased directly from their site as well. I believe they have another pedal power transformer as well

[kuzieem]

Can you elaborate how you imagine isolated ground? All pedals share the ground by instrument cable and their  DC sockets (-)  are wired to the same grounding so... what is the ground isolated from? I understand the isolation of V+, by feeding positive voltage to every pedal from different 7809 regulator.

[Travis]

A ground loop may arise as a result of having grounds connected in multiple places. By isolating the ground connections of the power supply, you reduce the chances of creating a ground loop

Each output from the transformer I linked to can provide an output with isolated power as well as isolated ground

[Pavlos]

Travis wrote

I’ve never found the huminator to be super effective but it has a lot of fans

Pehaps it works better with some circuts than others? just as some pedals seem to give their best with certain guitars, amps, or positions in a pedal chain? Of course it might also be that depending on exactly what is causing the hum might affect the degree of success in eliminating  or reducing it?

Travis wrote

One thing to keep in mind regarding the DIY project is that the outputs are not isolated from each other because they share a common ground. If you need truly isolated outputs, you could start with a transformer like this

I'd already realized about the shared gounds, but thanks for confirming it  thankfully never had any issues there so far, just with cheap noisy power supplies, hence asking for peoples thoughts, always good to know what's good and what to avoid, and if there are any batgains to be had......we all like a bargain now don't we

Travis wrote

A ground loop may arise as a result of having grounds connected in multiple places. By isolating the ground connections of the power supply, you reduce the chances of creating a ground loop

Each output from the transformer I linked to can provide an output with isolated power as well as isolated ground

Galvanic isolation??? might be miss-remenbering it but isn't it the interaction of electromagnetic fields that passes signal with a transformer, while a ground loop is because of the physical connection? bit like a magnetic pickup as opposed to a piezo?

[balazs.bencs]

Also, it is worth to mention that isolation can be solved without transformers if you are going to build a power supply.

You can get DC-DC converters that are isolated, which is a really useful thing, you can easily get them at mouser: https://eu.mouser.com/Power/DC-DC-Converters/Isolated-DC-DC-Converters/_/N-brwkv/

Have you seen the Gigrig power supply modules? They are so tiny because they are using DC-DC converters. I found a picture online, which shows their "Virtual Battery" guts and inside they have a Recom RN-0909S DC-DC converter to do the isolation, the rest of it is just filtering I think.

[Pavlos]

Yeah the Gigrig stuff looks really good, they've been doing a quite a few custom boards for pro's in the last couple of years as well, which has got to be a pretty good endorsement for quality. They've got some really practical ideas and the guy behind it also plays in a band called Tin Spirits with Dave Gregory (Formerly of XTC)

[Pavlos]

well I finally caved in to the lure of buying a nice shiney new power supply, and after loads of searching online and finding that most of what I liked the look of was either not quite as good a spec as the sales blurb made out, or rather too expensive for my meagre bank balance, I finally managed to find something here in the UK at what I hoped would prove to be a good buy, and at a decent price.........


balazs.bencs  
Many thanks for your suggestion, I am now the proud owner of a Palmer PWT05MKII
Arrived today in the post from Andertons (£83.68 inc carriage) and after a quick hour of playing, Ive got to say I'm impressed! built like a tank, plenty of connectors included and no additional noise from the PSU

I'm happy. my pedals are happy, everybody happy

[balazs.bencs]

So good to hear that you like it. I use it every day too, and it's really reliable, zero noise, true isolation (with a toroidal transformer - I looked inside :) ).

[Pavlos]

Well having seen the high quality of some of your builds I thought it was probably worth a try, so good call