One-Spot/Godlyke/Radio Shack power adapter question

K2000 · #1 02-02-2008, 03:15 PM

Can I run a daisy chain using any old 9 volt adapter?

Is there anything special about a One Spot AC jack, besides the small amount of space it takes up on a power strip? Could I attach the daisy chain to any generic 9 volt wall wart? Is it actually necessary to use a One Spot wall wart?

I've seen people refer to using Boss TU-2 tuners as a hub for daisy chains... why is that different/better than just using a regular One Spot daisy chain?

Mongo not smart

bassmodder · #2 02-02-2008, 03:23 PM

Well, the 1 spot is a switch mode power supply to my knowledge. This would explain the price that is attached to it.

SMPS do have voltage regulation built in so you will always get 9 volts. Even with it open circuit. They are also smaller and put out more amperage than standard iron core transformers.

I have had luck running FX off of both 9 and 12 volt non regulated power supplies though. AKA the radio shack specials.

The 1spot does have a proprietary connector on it though. Cut it off and solder the bare wire if you need to use their cord with a different power supply.

Pilgrim · #3 02-02-2008, 03:27 PM

The issue isn't voltage, it's amperage. Driving multiple boxes requires more amperage. As long as the 9V supply you're using provides as much or more amperage as the original unit intended to drive multiple boxes, it will drive the same number of boxes. It's easy to check specs (usually MilliAmps) on power supplies, and the output is normally either imprinted on the power supply or on a sticker affixed to the power supply.

I have a Warwick Rockbag with its own power supply, but I'm using that PS with a 1-Spot DC daisy chain to run three Boss pedals and one Behringer pedal. No problem.

bongomania · #4 02-02-2008, 07:07 PM

Quote:

Originally Posted by Pilgrim

The issue isn't voltage, it's amperage. Driving multiple boxes requires more amperage. As long as the 9V supply you're using provides as much or more amperage as the original unit intended to drive multiple boxes, it will drive the same number of boxes. It's easy to check specs (usually MilliAmps) on power supplies, and the output is normally either imprinted on the power supply or on a sticker affixed to the power supply.

+1 Also I'll disagree with the other guy who "had luck" with unregulated supplies. Unregulated supplies mean the voltage could be all over the map, several V higher or lower than the target, which may cause poor performance, extra noise, or even damage to certain circuits. Or you might be lucky.

Go with a regulated supply, there's no gambling there.

K2000 · #5 02-03-2008, 11:19 AM

Thanks for the replies. What's the purpose of using a Boss TU-2 tuner as a hub for powering pedals?

Thanks,
Mongo

Pilgrim · #6 02-03-2008, 02:20 PM

Quote:

Originally Posted by K2000

Thanks for the replies. What's the purpose of using a Boss TU-2 tuner as a hub for powering pedals?

Thanks,
Mongo

It doesn't relaly matter if it's a TU-2 or not, as Boss designs their pedals this way with a power port in and out. I use the TU-2 as the first pedal in my chain of 4. Power goes from the pedal board to the Boss, then using the daisy chain I come out of the Boss to the other three pedals.

JanusZarate · #7 02-03-2008, 02:58 PM

Quote:

Originally Posted by K2000

Thanks for the replies. What's the purpose of using a Boss TU-2 tuner as a hub for powering pedals?

Thanks,
Mongo

No reason, really.

The TU-2, PSM-5 (discontinued), LS-2, and NS-2 have "DC Out" jacks because Boss would like to have you believe you're supposed to use them to power Boss pedals.

Compare a Boss daisy chain to a 1 Spot daisy chain, and you'll quickly see why. All of the plugs on the Boss daisy chain are male; you can't plug a wall wart directly into one of those chains. So, how do you do it? You use a Boss pedal with a pair of DC jacks instead, to serve as the link. It doesn't do anything else other than start the chain.

A 1 Spot daisy chain, on the other hand, has one female plug on it. You can plug your wall wart directly into that chain, so you don't need a pedal with a DC Out jack.

IMHO, the Boss daisy chain is horrible. It's short, impractical, and the marketing is deceptive. It's only decent if all of your pedals are Boss.

bassmodder · #8 02-03-2008, 04:19 PM

Notice I did not recommend the unregulated ones.

There are many other SMPS adapters out there if money is an issue for you. Most put out well over an amp too. Check closets for old broken, useless equipment at work.

The SMPS are usuially smaller and lighter, but make sure to measure them with a volt meter before placing them into use.

Thangfish · #9 02-03-2008, 05:02 PM

Quote:

Originally Posted by bassmodder

I have had luck running FX off of both 9 and 12 volt non regulated power supplies though. AKA the radio shack specials.

The 1spot does have a proprietary connector on it though. Cut it off and solder the bare wire if you need to use their cord with a different power supply.

The connector on my 1Spot was standard. Plugs into the daisy chain or any of my pedals individually, or the built-in daisy chain jack on my pedal board.

Thangfish · #10 02-03-2008, 05:10 PM

A while back, I purchased a Radio Shack ps as a back-up for my 1Spot.

The thing hummed so bad as to make it unusable. It's just been laying around. I went to grab it after reading this thread, and it says NOTHING on it as far as switch-mode or regulated output.

Now I'm POSITIVE that this was specified on the package when I bought it, but after going on the RS web site just now, there is also no mention in the specs posted there. Cat no. 273-1771

It must be a switch mode PS because it is physically small and light and is rated at 1500ma... right? By way of description it also has a large choke on the output (rf filter?).

Anyway, I have seen this ps recommended by manufacturers of other equipment as a replacement, in the same paragraph as the warnings NOT to use a non-regulated PS.

Anyone care to speculate as to why it hums so badly?
I thought switch mode power supplies were not supposed to hum.

musicelectronix · #11 02-03-2008, 05:29 PM

Using an unregulated/unfiltered DC power supply is like opening a door to troubles. Let's go over some stuff first. What does regulated means? When used for DC power, it can actually mean two things: Regulated voltage and regulated current. Regulated voltage means, regardless of the current or power rating of the device, the power supply will feed the device with a certain voltage. Regulated current means, regardless of the voltage requirements, the power supply will feed the circuit with a stable current. It is a common problem that most of the transformers leaks AC voltage into their DC output and most of the noise problems are the results of this.

Generally speaking, when we refer to apower supply as "stompbox power supply", it is 9VDC regulated/filtered power supply. So what happens if it is not regulated AND filtered.

1- An unregulated power supply's output voltage is determined by the pedal you plugged it in. Let's say it is capable of 900 miliwatt power. When you plug a low power consumption pedal, lets say 60 mA, simply the output voltage will be 900/60=15 volts. That's right! your 9V radioshack adaptor will feed your beloved pedal with higher voltage. Most of the pedals are safe for 16VDC, but you considerable drain the life of the electrolytic caps' and some of the semiconductors' life. And they won't sound as good too, since they were calibrated for 9VDC

2- not properly filtered/not filtered power supplies leak AC voltage into their output. The most common symptom is 70hz hum. Most opamp based designs may compansate for this, but many transistor or JFET based circuits WILL do the humming, if they are not used with a filtered power supply. Opamps will TOLARATE the AC leakage, do not filter it.

So, radioshack power supplies may be ok for your electric shaver, but not for your pedals.

niftydog · #12 02-03-2008, 05:37 PM

Just to back up what musicelectronix has already said...

There's two really important things to consider; Regulation is only one of them - the other is FILTERING. Regardless of whether it's linear (old style, heavy) or switch mode (new, compact, light), if the filtering is bad it will hum.

I'd suggest to Thangfish that you are just in possession of a somewhat mediocre power supply. Although, hum can also be caused by ground loops, and it's possible that power supply does something to encourage ground loop hum.

Thangfish · #13 02-03-2008, 05:43 PM

Quote:

Originally Posted by niftydog

I'd suggest to Thangfish that you are just in possession of a somewhat mediocre power supply.

I would suggest that your suggestion is 100% accurate.

It's going back in the shoe box, where it lived a peaceful, meaningless existence until I disturbed it from it's rest just for this thread.