Jump to content
Why become a member? ×

Cheap power supplies?


SwamiRob
 Share

Recommended Posts

Seen a few cheap power supplies on ebay and was wondering if they are gonna be ok or whether they are too good to be true. In particular there's one called from a brand/is branded by Caline or something similar, that has several 9V outputs, a 12V one and a 18V one, and claims they are all isolated. Have seen alot of decent reviews for it and there's a few gash ones but has anyone here got any experience with anything like this?

Link to comment
Share on other sites

I have the caline and its doing a decent job. I'm running a tuner, hartke bass attack, micro q tron, boss flanger, boss limiter enhancer and a zoom 506 off it right now, all holding up well. Good value for money. Not sure how it would handle a more exotic set up but there's room for more pedals should I want to add them on. I'd say go for it.

Link to comment
Share on other sites

Cool! Don't need anything fancy, just a tuner, distortion and an 18v compressor, although the distortion has some magic voltage doubling going on or something so hopefully that wouldn't mess anything up.

In what situations DOES isolation matter by the way? As long as there isn't too much buzz I'm happy!

Link to comment
Share on other sites

[quote name='ProfFrink' timestamp='1456175658' post='2986348']
AFAIK these are not really isolated. OTOH most pedals don't really need fully isolated power to work well.
[/quote]

The problem with multiple output power supplies being described as 'isolated' is a problem with terminology.
In normal 'electronics language' "isolated" would mean galvanic isolation ie the "Ground" terminals of the outputs (as well as the positive terminals) are not commoned in the power supply.
But some of the multi output power supplies available and described as "isolated" do have a common ground.
The "isolated" aspect appears to refer too the fact that the outputs have independent protection against over current / short circuit etc - ie if one output is short circuited or asked to provide too much current then the other outputs shouldn't be affected.
"independent" would be a better term rather than "Isolated".

Oddly, the Thommann Powerplant does not have Isolated Outputs whilst the Powerplant Junior does (with fewer outputs than the Powerplant). I verified this with Thommann before purchase.

Link to comment
Share on other sites

[quote name='SwamiRob' timestamp='1456182393' post='2986458']
Cool! Don't need anything fancy, just a tuner, distortion and an 18v compressor, although the distortion has some magic voltage doubling going on or something so hopefully that wouldn't mess anything up.

In what situations DOES isolation matter by the way? As long as there isn't too much buzz I'm happy!
[/quote]

If you're running pretty much any sort of digital pedal ie it has clock signals inside it then you're likely to run into problems with non-isolated or daisy chain supplies. In this case the digital effect is causing noise which affects the other pedals.
With non digital effects the situation is a bit more nuanced.
With non isolated or daisy chain supplies you are , by definition, introducing 'Ground Loops' (since the patch lead between the pedals is providing a 'Ground' path in addition to the power supply ground). This loop is liable to have noise induced into it. Whether this happens to a significant degree depends on the geometry of the loop and sources of interference.
For instance there may not be a problem until you are near a lighting rig / fridge / laptop etc.
Minimising the loop area (basically short leads and lead dressing) will give best results.

You can try various 'tricks' with the patch leads - inserting permutations of resistors and capacitors in the shield path to provide isolation at lower frequencies and continuity at higher frequencies - essentially a 'Ground Lift' approach - my advice is don't :-)

Link to comment
Share on other sites

[quote name='rmorris' timestamp='1456224988' post='2986722']
If you're running pretty much any sort of digital pedal ie it has clock signals inside it then you're likely to run into problems with non-isolated or daisy chain supplies. In this case the digital effect is causing noise which affects the other pedals...

[/quote]

Cracking advice in both of your posts...

Link to comment
Share on other sites

I'm using the Harley Benton Junior (and the Palmer version of the same unit) the isolated nature of the outputs makes it easy to get 18V or 240mA, I'm running a blowtorch at 18v and the high current for my G30, I've had no issues and 2 of my friends are using the same units with no problems it's a bargain really! they both came with the current doubler cable and the 18v cable is easy to make if you've got a soldering iron

Matt

Link to comment
Share on other sites

[quote name='Matt P' timestamp='1456231583' post='2986808']
I'm using the Harley Benton Junior (and the Palmer version of the same unit) the isolated nature of the outputs makes it easy to get 18V or 240mA, I'm running a blowtorch at 18v and the high current for my G30, I've had no issues and 2 of my friends are using the same units with no problems it's a bargain really! they both came with the current doubler cable and the 18v cable is easy to make if you've got a soldering iron

Matt
[/quote]
[quote name='ahpook' timestamp='1456231010' post='2986801']
Cracking advice in both of your posts...
[/quote]

Thanks.
and that's the other plus with isolated supplies - since they are 'floating' you can stack them up to give higher voltage (and parallel for more current if the design allows)

Link to comment
Share on other sites

I've got one of these , i decided I'd grab one on a punt with some Amazon vouchers and it seemed the best well reviewed , Im very happy with my choice.
.
[url="http://www.amazon.co.uk/gp/product/B010DLUSS4?psc=1&redirect=true&ref_=oh_aui_detailpage_o01_s00"]http://www.amazon.co...ailpage_o01_s00[/url]

So far no complaints with the actual function of the thing . minor niggles are the fact that its own power supply cable from wall to unit isn't particularly long ,but I swapped it for another identical one from
another pedal with a longer cable. I'm using it to power a Zoom B3 , at 9volt BDI21 at 9 volt , digitech bass synth at 9 volt and a wireless unit at 18Volt , I was even using it to power my little hot-tone
mini bass head which was also at 18 volt ..

Another minor downside for me is that all the included power leads are the same length it would be nice if some were shorter ... but i was able to tidy cables up underneath pedal boards etc.
It introduces No discernible noise in the chain ... its compact and being able to turn on all the LED's was amusing when we decided to turn the lights off in the studio to test how well we new some songs.

Edited by synthaside
Link to comment
Share on other sites

  • 2 weeks later...

[color=#141414][font=verdana, geneva, lucida,]
Got a cheap one in the end, but the build quality seems pretty decent and was well packaged and everything with plenty of options for leads, having one for each output and polarity flipping one and a mini jack output one for good measure. Only thing I had to do was get a 2.1mm to 2.5mm adaptor for my Trace compressor. Works very quietly and was great at the gig I played last night.[/font][/color]
[color=#141414][font=verdana, geneva, lucida,]
[/font][/color][color=#141414][font=verdana, geneva, lucida,]
[/font][/color]

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...