Need Mackie Big Knob studio plus schematic

[Dehn]

Hi Everyone,

Does anyone have the schematic for the studio plus big knob, and not the one on the mackie site.
My unit has the separate 18v power supply, the problem with mine is I only get the -15v supply and not the +15v side on the main CBA.
Many thanks in advance!

[Dehn]

Please!

[Enzo]

Did you directly contact customer service at Mackie and ask for it? Big Knob is a series of models, and if they have one on the web site, it may be a different models from yours, but they do not just put ALL their schematic files on the web site.

[vintagekiki]

Please!

https://supportloudtech.netx.net/loud-public/#category/10959
MACKIE

https://supportloudtech.netx.net/loud-public/#category/19965
Big Knob

[Dehn]

Thanks Enzo for the reply, I did call mackie and they said they wouldn't send me the schematic because: 1, i'm not a warrantry servicier and 2: because the unit is still in production.
Anyone have this? Also thanks to vintagekiki for replying but I already found the schematic you're referring too it's just not the right one.

[Jazz P Bass]

I cannot imagine that Mackie drastically changed the power supply.
https://supportloudtech.netx.net/lou...category/19965
It should be fairly easy to verify that the supply puts out the +15 & -15Vdc.
Unless you have an issue after the supply (something loading it down).
Have you disconnected header J2 to see if the supply itself works?

[Dehn]

Thanks for replying jazz p bass, Yes i'm assuming it's still a plus and minus 15v supply, but i'm only getting the -15v. no +15v on a IC I checked. This unit uses a stand alone wall wart type of power supply that outputs +18v. the schematic on the mackie web site uses a internal power supply with a computer type power AC plug.

[nosaj]

Thanks for replying jazz p bass, Yes i'm assuming it's still a plus and minus 15v supply, but i'm only getting the -15v. no +15v on a IC I checked. This unit uses a stand alone wall wart type of power supply that outputs +18v. the schematic on the mackie web site uses a internal power supply with a computer type power AC plug.

Check your +15 rail for short to ground.
nosaj

[Jazz P Bass]

Have you opened the unit up?
I would be curious to see how they get +15Vdc & -15Vdc out of a +18Vdc 23 watt power pack.