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DIY Stompboxes => Building your own stompbox => Topic started by: Phend on July 08, 2023, 06:51:29 AM

Title: Power supply make or buy
Post by: Phend on July 08, 2023, 06:51:29 AM
Hello
Any comments on this topic?
Diy is probably the most satisfying.
Purchase can be cheap, but cheap is probably cheap.
Thanks
Title: Re: Power supply make or buy
Post by: GibsonGM on July 08, 2023, 06:57:56 AM
I think it depends on what you want it for. A bench power supply for pedal testing or what have you, that can be fun to build (educational) and you can build in some functionality you might not get elsewhere.  Or for a small amp or whatever.

For running a pedal board, IMO it's easiest, most economical and reliable to just buy something. There are many companies with good reputations in this regard.

As always, YMMV!
Title: Re: Power supply make or buy
Post by: Phend on July 08, 2023, 07:12:38 AM
In this case the power supply is for 9 volt effects.
Maybe 6 DC outputs.
Title: Re: Power supply make or buy
Post by: bluelagoon on July 08, 2023, 09:54:08 AM
Have to recommend the Strymon Ojai. You cant make them for as cheap or as efficient, well built, functional or as pretty as the Strymon
for less than you will pay for the store bought unit. You can try!

https://www.macronmusic.com.au/strymon-ojai-r30-hi-current-power-supply
Title: Re: Power supply make or buy
Post by: ElectricDruid on July 08, 2023, 10:24:04 AM
I've recently built a Eurorack power supply using these:

https://uk.farnell.com/mean-well/irm-30-12/power-supply-ac-dc-12v-2-5a/dp/2815509

Dead easy to use - you just feed it AC mains and it does the rest, pretty much. Quiet enough for audio. Unfortunately they don't make a 9V one, but I bet someone else does. 2.5A output is enough for 6 outputs at 400mA.
Title: Re: Power supply make or buy
Post by: R.G. on July 08, 2023, 10:31:44 AM
There are two questions lurking here.

First, do the effects require ground isolation for technical as opposed to la-di-da internet fussy reasons? One technical reason might be positive ground versus negative ground pedals. Another might be bad-actors pedals that behave so poorly that they need a protective environment for their grounds.

Second, how much do YOU value education/fun from building versus convenient and reliable packaging and hookup? I can make a technically-better power supply than I can buy. But it will take a long time, cost more, and have clumsier packaging. Your actual use also gets into the evaluation. Are you playing only at home? Or do you lug your creations out to play gigs? Playing gigs is a big recommendation for getting a well packaged commercial supply.

GibsonGM is right: There are companies with very good reputations for effects power supplies. A little research can save you a lot of time and perhaps money.

Full disclosure: I work for Truetone; this lets me see the insides and inside-the-company way they're designed, sourced, sold, and supported. You do your own research. I suggest you look at the 1Spot line and its reputation.


Title: Re: Power supply make or buy
Post by: stallik on July 08, 2023, 10:32:52 AM
Isolated outputs or not? Big difference in price/complexity. Some 'isolated' supplies really aren't.

My board runs quietly on a 2 output 9v/12v diy job with the 9v daisy chaining everywhere. Big dual toroidal, 2 variable power/filter boards. If not for the 12v requirement, my 1spot would do the job. So impressed with it that one of their larger units would be my first choice if I needed true isolation.

However, the GigRig has just announced a new power block for their modular system which looks interesting

Edit: RG beat me to it ;)
Title: Re: Power supply make or buy
Post by: Phend on July 08, 2023, 11:43:38 AM
Looking at Pin Negative (for NPN builds).
Negative Ground.
Home use only.

I found this note on this web site:
https://www.instructables.com/Build-A-Power-Supply-For-Your-Guitar-Pedals/
"IMPORTANT NOTE: Depending on what pedals you intend to use this for, you should take care to wire the DC connectors as pin-positive/ring-negative or pin-negative/ring-positive. The latter is the industry standard way of doing it, although it poses issues when building a pedal that has a metallic housing. I prefer pin-positive/ring-negative because of that issue, and I wired this supply in this way."

Issue with Pin Negative, not sure I understand unless using metal "jacks"

And Yes I have fun building one offs, plus the education.
Hammond enclosure ?
Cost, no issue.

Thanks all for the suggestions..
Title: Re: Power supply make or buy
Post by: Kipper4 on July 08, 2023, 12:32:37 PM
I got a second hand lab type power supply from a mum and pop electronics store for 20 bucks. I don't know if I just happened on it at the right time but it's a super little unit.
Voltage and current readings.

Hope you find the best solution for you.
Rich
Title: Re: Power supply make or buy
Post by: Rob Strand on July 08, 2023, 12:33:52 PM
Quote"IMPORTANT NOTE: Depending on what pedals you intend to use this for, you should take care to wire the DC connectors as pin-positive/ring-negative or pin-negative/ring-positive. The latter is the industry standard way of doing it, although it poses issues when building a pedal that has a metallic housing. I prefer pin-positive/ring-negative because of that issue, and I wired this supply in this way."
QuoteIssue with Pin Negative, not sure I understand unless using metal "jacks"
All it's saying is the author prefers positive tip in order that the metal jacks connect the negative to the casing.  Connecting the chassis to the incoming power isn't a good idea anyway.  IMHO it's a cop-out so the author doesn't have to deal with it.

The construction in that article is potentially dangerous:
- The transformer is exposed.  The mains windings can be damaged and exposed to the user.
   It technically needs a grounded cover.
- glued down caps inside an enclosure with mains inside, then exposed mains wiring on top of that.

You would be better off using an external wall-wart which then plugs into a box that does the regulation.   Non isolated outputs works fine in many cases. You can help isolate the supplies with small resistors in series with the -ve of each output.  Non isolated outputs aren't suitable for positive ground pedals that's where you need either isolated supplies.   Another option for positive ground pedals is to have a few negative outputs but that complicates things a bit.
Title: Re: Power supply make or buy
Post by: R.G. on July 08, 2023, 02:15:21 PM
Good point Rob. Having a cheap, fun to build power supply isn't worth dying for.   8-|

Safe construction is part of what you pay for with  commercial power supply, and there is usually at least some effort in a commercial supply to meeting formal safety standards. Home brewed supplies often have big safety issues.

@Phend: there is quite a number of articles on power supplies and power issues at geofex.com, going back to about 2000. You might like reading through them. google "geofex power" to get started.
Title: Re: Power supply make or buy
Post by: Phend on July 08, 2023, 03:22:56 PM
Thanks Rob and R.G. :
Yes I can work with 120 v, but to construct a safe unit, fused, switched etc and make it UL would not be worth it. Just running a 3 prong cord into it is a design project. Plus the mounting of components.
With that said I have looked at various supplies.

Truetone is an option. As is strymon ojai.
Truetone makes their Pro unit and the Truetone 1 Spot Combo which is inexpensive.

The 1 Spot could be taken a step further, don't laugh, for a cleaner distribution, purchase a Hammond box or make a wood one, and get a bag of barrel jacks. Run the 1 Spot into a jack which connects to a MC8 (inside the box) which in turn connects to a array of barrel jacks wired to jacks mounted thru the wall of said box. Getting the wiring nice and clean inside (partition is required).
Title: Re: Power supply make or buy
Post by: ElectricDruid on July 08, 2023, 03:46:37 PM
Quote from: R.G. on July 08, 2023, 02:15:21 PM
Home brewed supplies often have big safety issues.

While I entirely agree, I'd say only if you're damn lazy, frankly. It's not hard to make something that's really, genuinely safe - it just takes a bit more effort and bothering to get the right parts (like putting heatshrink over mains connections, for example).

But a lot of people *are* pretty lazy, so you do see a lot of dodgy stuff out there. I save my laziness for situations where mains voltage is not concerned!


Title: Re: Power supply make or buy
Post by: R.G. on July 08, 2023, 04:14:42 PM
I think the issue is more not knowing the details of what safety is than in laziness.

The fundamental mantra of safety certification is that the failure of any one component (including the worst possible one!) should not allow a thermal or electrocution hazard to happen. The ramifications of that get tricky.

For instance, what if the failing component is a layer of insulation between primary and secondary inside the power transformer? The answer to this one and the other primary wiring insulation instances is either to provide a solidly safety grounded shell, or to make two layers of primary insulation for all primary wiring. That is, either safety ground the whole thing, every single user-touchable metal part; or to put in two layers of insulation - the so-called double insulation method.

What if one of the primary wires breaks loose at one end/solder joint and slips out of its heat shrink? The answer is to mechanically secure all wires carrying hazardous voltages so that if any one wire breaks, the loose end is restrained from touching any user-accessible metal, or can only touch a safety grounded surface.

What if a voltage transient comes down the AC line and breaks over between a primary wire and a secondary wire? The answer is (1) require high-potential testing up to about 4000V with no breakover (try that one at home; I once did it with a variac and a neon sign transformer, but I still get twitchy thinking about the test setup) and (2) require enough creepage and clearance distance between primary and secondary wires to withstand that kind of transient even over a PCB dusted with greasy dust and bar funk for a few years.

All of this kind of thing is reasonable once you're exposed to it for a while, but it's not obvious to someone who hasn't been through a safety certification test program. That's what makes me think the exposure is more being new/naive than lazy.
Title: Re: Power supply make or buy
Post by: antonis on July 08, 2023, 04:35:52 PM
Quote from: R.G. on July 08, 2023, 04:14:42 PM
That's what makes me think the exposure is more being new/naive than lazy.

Unless you make a PS for someone else, with bad intentions.. :icon_wink:
Title: Re: Power supply make or buy
Post by: PRR on July 08, 2023, 05:59:13 PM
Quote from: R.G. on July 08, 2023, 04:14:42 PM......high-potential testing up to about 4000V with no breakover (try that one at home; I once did it with a variac and a neon sign transformer, but I still get twitchy....

Electric fence charger. The cheapest one in Tractor Supply claims 2.8KV. The tester sold on the same aisle blips the 4KV neon even with 100 feet of damp horse-tape. (However reading close it may claim 2KV or 977V..... CYA??) 

(https://i.postimg.cc/ZvFjmqMm/2-Mile-Charger.gif) (https://postimg.cc/ZvFjmqMm)

No, pulse testing is not as strenuous as steady voltage. OTOH most KV surge around the house will be brief. Otherwise bigger stuff will arc/smoke.

And a fence charger can "give you a lesson" and you probably not die of it: these things have few warnings and the company has been in business for years, so the total jolt must be not-real-lethal.

I know that 30KV *once* cured me of working on live parts.

Title: Re: Power supply make or buy
Post by: stallik on July 08, 2023, 06:07:37 PM
Probably the wrong way to think about it but, if my PS build electrocuted me, that would be it. In a second or two. On the other hand, if it were to short, cause a fire and burn the house down, I'd never hear the end of it.

Title: Re: Power supply make or buy
Post by: ElectricDruid on July 08, 2023, 07:08:55 PM
Quote from: R.G. on July 08, 2023, 04:14:42 PM
I think the issue is more not knowing the details of what safety is than in laziness.

Ok, but you can *look up* the details if you don't know, and not doing that is laziness. It's not like this stuff hasn't been done a hundred times before. There's stuff out there that you can find that tells you what you need to do. You just provided a very succinct summary in four paragraphs, so it's not exactly impossible.

But yes, I agree, when you don't know what you don't know, it's easy to get yourself in a twist. In that position, you should at least know enough to stay away from mains, surely?!

Title: Re: Power supply make or buy
Post by: Rob Strand on July 08, 2023, 07:39:34 PM
QuoteBut yes, I agree, when you don't know what you don't know, it's easy to get yourself in a twist. In that position, you should at least know enough to stay away from mains, surely?!
That's pretty much it.    "Safe" viewed by experienced eyes is very different to "Safe" viewed by electronics people in general.

Using wall-warts is a good way to keep away from mains.    It also reduces the complexity and size of the project, and even the cost.  In simple terms if you can't let your children use it with electrocuting themselves or put it under your bed at night without it catching fire one day you shouldn't build it or use it!

If you just have a regulator in a box it can be pretty darn small,

(https://i.postimg.cc/21bh8CnP/9v-regulator.jpg) (https://postimg.cc/21bh8CnP)
Title: Re: Power supply make or buy
Post by: MrStab on July 08, 2023, 10:52:02 PM
For what it's worth, RG's deterrence years ago forms the bedrock of my own cautiousness when it comes to mains AC.

I still use one of the PSUs I nonetheless built on a regular basis, and the one preceding that still works well after many a gig. Both fused, safety-earthed with sufficient crimping and tooth washers, live wiring isolated from chassis, firm, reliable mounting and ample spacing between pre/post rectification. Then came the DIY power amps. The safety modifications to non-compliant Chinese equipment are now second-nature. The repairs to commercial mains equipment are still undertaken very carefully. Self-doubt a must at any level of experience.

So thank you for telling me not to do it. In a counter-intuitive way, despite the fact I ignored the advice not to try any of it, it's probably why I'm still here!

Don't do it, OP. You legitimately may die in an instant. I may have done so. It's really not something anyone will want to encourage while being able to still sleep at night. But there is a whole grey area of a philosophy behind how you choose to proceed. Don't skimp on any research.
Title: Re: Power supply make or buy
Post by: GibsonGM on July 09, 2023, 07:27:06 AM
The old conundrum - safety vs. learning, growing, understanding and gaining competence.   Working w/mains-wired projects is certainly no more (or is it less?) dangerous than learning to operate a chain saw.   I think perhaps the deciding factor might be if there is someone who ACTUALLY is knowledgeable - not a 'poser' - who could tutor you as you step into the land of transformers, fuses, safety grounds and the like.  Uncovering/understanding the hidden dangers that aren't intuitive BEFORE they get you is critically important (just like chain saw kickback dangers).

I could do home wiring before I could safely build mains-powered stuff. This probably helped a lot - the repetition of hot, neutral, ground and what they do. Safety routines that become 2nd nature ("lock out/tag out", pre-powering safety review).  It's not something I'd say 'don't ever learn!' - but I'd really want the new person to have the proper guidance because yes, there are a few ways one can kill themselves pretty easily if they mess things up!   There are also methods to test what you've built without putting yourself in jeopardy before you 'use' the device.

Nothing can replace training, IMO - an adult ed course, or even your father in law IF he's competent :)   Don't be afraid, but be very respectful of things that can potentially end you.  And weigh how much the end goal is worth vs. what you're willing to learn and apply before engaging in the potentially dangerous activity...that's why my earlier reply of 'just buy the thing'.   Something moved and used hard will have been failure-tested by the company that made it, where we really can't do that stuff, so we can't know how it will eventually 'die' on us (and maybe present a shock hazard).
Title: Re: Power supply make or buy
Post by: amptramp on July 09, 2023, 08:12:28 AM
If you are making something to sell, you need to have UL or CSA compliance in North America or VDE in Europe.  If you are building a single item to sell, sell the wall wart with it that has these certifications or you will be liable for any damage caused by faults.

Even if you are updating an amplifier from a 2-wire plug to a 3-wire plug, there are certain requirements that are not obvious: if the ground lead is connected to the chassis via a terminal lug, this hardware cannot be used for anything else.  I have seen amp repairmen use the mounting screw for a transformer as the place to put a ground lug and that does not meet UL/CSA requirements.  Similarly, you can only use certain types of wire on the primary side in order to comply with the code.

If you are building something for yourself, there are ne restrictions, but you are still liable for damage if things go wrong.  There have been hundreds of magazines of DIY projects for stuff you plug into the AC line and companies making kits where the capabilities of the builder are in doubt but as long as the unit has the capability of meeting standards, you are pretty much OK.
Title: Re: Power supply make or buy
Post by: Phend on July 09, 2023, 09:40:58 AM
Here are two of my electrical projects from many years ago.
Dismantled for the most part.
UL (Uderly Loony) builds not approved. DANGEROUS PROJECTS (I am lucky)
First was a modified power supply (Heathkit TV build unit) a friend gave me.
I added a powerstat, rectifier (not shown), capacitors, high watt resistors, pots etc. to the inside of the unit.
Project: Anodize Titanium using TSP and an artist brush wired to DC.
The second project was a ruby laser. I polished the ruby rod and added flash tubes etc.
So let me think. :)  General Guitar Gadgets has a few circuits as well as the net.
Or those nice (not cheapo units) PSU's for sale.
Thanks for the input.


(https://i.postimg.cc/68m9c5Kj/1.jpg) (https://postimg.cc/68m9c5Kj)

(https://i.postimg.cc/3y03c5JK/2.jpg) (https://postimg.cc/3y03c5JK)

(https://i.postimg.cc/47zsX69q/3.jpg) (https://postimg.cc/47zsX69q)

(https://i.postimg.cc/Zv4ZnWPR/4.jpg) (https://postimg.cc/Zv4ZnWPR)

(https://i.postimg.cc/14QNwMJg/5.jpg) (https://postimg.cc/14QNwMJg)

(https://i.postimg.cc/V0gwCz4F/6.jpg) (https://postimg.cc/V0gwCz4F)


Quotedangerous than learning to operate a chain saw

Ha, just bough an electric one (battery) that is.
Title: Re: Power supply make or buy
Post by: MrStab on July 09, 2023, 11:06:18 AM
It can be helpful to actually see a lot of commercial, certified mains equipment, and how it's done.

...without them being plugged in. With at least a decade since last power cycle, to ensure sufficient cap discharge. And various other disclaimers to absolve me of responsibility.
Title: Re: Power supply make or buy
Post by: GibsonGM on July 09, 2023, 11:46:12 AM
Ha, just bough an electric one (battery) that is.

I have a Stihl MS290 that I use to cut a 10-cord load of trees into ~8 cords of stacked wood every year. That's what I heat with.  B@stard will take your leg right off in 1 second if you're not careful, but it's a great tool I've had for a decade with NO problems.  Go thru at 20" log in about 10 seconds.

Also used to clear the occasional tree from across the road, since this is rural Maine!  :)  We keep one in the truck.

I'd like a cordless for going up in trees to remove dead limbs - seems like it might be lighter.  Or for cutting fence posts (4x4, 6x6), things like that.

Will it quarter a moose?
Title: Re: Power supply make or buy
Post by: Phend on July 09, 2023, 02:13:46 PM
Yes, DeWalt XR 20v 12 inch, you could climb trees with it, I've cut 12 inch butternut like going thru butter. 250$ at Ace Hardware.
With proper attire (red flannel) yes. Always wear your safety glasses.
Up next, what PSU ?
Title: Re: Power supply make or buy
Post by: Phend on July 09, 2023, 02:28:40 PM
Considering making this 8 holer.
Hammond 1590DEBK (7.88 x 4.73 x 2.53) black
Have terminal strips, led, and switch from a past projects.
Buy DC Button Jacks.
Power Unit : Truetone 1 Spot 9v 1700mA

(https://i.postimg.cc/9D9M2F44/1-POWER-SUPPLY.jpg) (https://postimg.cc/9D9M2F44)

(https://i.postimg.cc/7CyLZ87K/2-POWER-SUPPLY.jpg) (https://postimg.cc/7CyLZ87K)
Title: Re: Power supply make or buy
Post by: GibsonGM on July 09, 2023, 03:49:33 PM
Most important safety equip. in my world - chaps!  The mylar can stop a chain from taking your leg off. Steel toe boots, too.

That distribution box is pretty nifty :)
Title: Re: Power supply make or buy
Post by: Phend on August 04, 2023, 03:18:43 PM
Just completed a distribution box for a Truetone 1Spot.
Thanks RG for sending me there.
Added a switch and a Led with resistor.
Tested voltages and had to do some head scratching.
1 Spot plugged in, switch on, led lights and getting 9.52 volts at each outlet and across the strips.
OK simple enough circuit this one.
1 Spot plugged in, switch off, led off, getting about Negative 2 volts.
Disconnect led and get Negative 0.3 volts.
Hum, tried a diode, no effect.
So thinking maybe a 100k bleed resistor (if that is what it is).
Bingo
On : 9.52 volts
Off : 0.000 volts instantly.
Now time to build the third (of seven) accessories.

(https://i.postimg.cc/wyypkBX4/IMG-8164.jpg) (https://postimg.cc/wyypkBX4)

(https://i.postimg.cc/4HpRrFFz/IMG-8165.jpg) (https://postimg.cc/4HpRrFFz)

(https://i.postimg.cc/bsjhQpsL/IMG-8167.jpg) (https://postimg.cc/bsjhQpsL)

(https://i.postimg.cc/MXBwMvKv/IMG-8168.jpg) (https://postimg.cc/MXBwMvKv)
Title: Re: Power supply make or buy
Post by: PRR on August 04, 2023, 07:26:04 PM
Quote from: Phend on August 04, 2023, 03:18:43 PM
Just completed a distribution box....

Nice work. But uh....

Why not a couple 8-way WAGOs?
https://www.amazon.com/Connector-PCT-218-Classified-Conductor-Terminal/dp/B08ZSFXWN7/
(https://i.postimg.cc/xcwXbwbH/41-HNMv8aj-PL-SX385.jpg) (https://postimg.cc/xcwXbwbH)
Title: Re: Power supply make or buy
Post by: DIY Bass on August 04, 2023, 07:31:43 PM
This power supply kit/pcb looks well done to me.  240v though.  You would need a different set of transformers if you lived somewhere that doesn't provide 240v

https://guitar-electronics.eu/en_US/c/Power-Supply/102
Title: Re: Power supply make or buy
Post by: Phend on August 05, 2023, 06:58:02 AM
QuoteWhy not a couple 8-way WAGOs?
I had the terminal strips from another project.
Will remember the cable management gizmo, PRR.
The 1 Spot has a daisy chain accessory option.
Plus they sell "boxed up" PSUs , a higher level.
But thought I wold build my own daisy chain in a box.
Just another DIY project. Needs a label.
PS The four screws washers and nuts were pricey, like all fasteners.
  I didn't go broke buying them, just saying.
Title: Re: Power supply make or buy
Post by: stallik on August 05, 2023, 11:27:49 AM
Nice solid build. Probably last much longer than mine but I doubt it would fit in the tiny space under my pedalboard
(https://www.stallibrass.com/images/las/daisy%20box.png)
Title: Re: Power supply make or buy
Post by: PRR on August 05, 2023, 12:41:20 PM
Quote from: Phend on August 05, 2023, 06:58:02 AM
  I didn't go broke buying them, just saying.

No. But a lot of stripping and screwing. And busing and crimping. Appropriate if you get paid by the hour. It occurred to me that non-wirepersons might not know the newer (~~30 years) inventions in the field.

"WAGO" is a brandname for similar push-in multi-connectors. The piano-lever connectors are something else, but I was getting Asian copies. Image search, 8-way connector, may be a start.
Title: Re: Power supply make or buy
Post by: antonis on August 05, 2023, 02:25:49 PM
IMHO, use of WAGO or any other similar connector device is overkill.. :icon_wink:

P.S.
I DO use a lot of those connectors in power supply builds of 5 Amps (or more) but for pedal supplies...  8)
Title: Re: Power supply make or buy
Post by: Phend on August 05, 2023, 03:51:39 PM
Not thinking about mfg these in large quantities, too old for that, like I am done.
But I did have Fun building it and I needed one.
Thanks for all the input on all post in this topic. !!
Title: Re: Power supply make or buy
Post by: Rob Strand on August 05, 2023, 07:58:14 PM
Since you went for a regulated power supply you might want to add a dummy load of 220 ohm (1W) inside the unit.   While perhaps not require for use with the One-spot, in general some power supplies are very noisy with light loads.  There's quite a few posts in recent years on this forum about it.  The dummy load saves the day in many of those cases.
Title: Re: Power supply make or buy
Post by: bluebunny on August 06, 2023, 05:27:35 AM
Quote from: stallik on August 05, 2023, 11:27:49 AM
(https://www.stallibrass.com/images/las/daisy%20box.png)

What a good idea, Kevin.  This would use up some of those metal-bodied DC jacks I bought by mistake.  :icon_rolleyes:
Title: Re: Power supply make or buy
Post by: stallik on August 06, 2023, 05:41:58 AM
^ you must have read my mind - that's precisely my reason for using them and I've still got enough  for another 2 boxes should I need them :icon_redface:
Title: Re: Power supply make or buy
Post by: Ben N on August 06, 2023, 08:07:07 AM
Quote from: Phend on August 04, 2023, 03:18:43 PM
Just completed a distribution box for a Truetone 1Spot.
The 1Spot is great, and I use one. But if you had 12vdc coming in, you could have separate regulation + filtering on each 9v output, in addition to 12v where needed.
Title: Re: Power supply make or buy
Post by: Ben N on August 06, 2023, 09:27:34 AM
Quote from: DIY Bass on August 04, 2023, 07:31:43 PM
This power supply kit/pcb looks well done to me.  240v though.  You would need a different set of transformers if you lived somewhere that doesn't provide 240v

https://guitar-electronics.eu/en_US/c/Power-Supply/102
Looks good and reasonably priced for 4x9v/420ma fully isolated, regulated, keeping in mind that 420ma can feed a lot of analog pedals on a daisy chain, or a single digital monster.