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MXR Iso-Brick

#102
JimmyM said:
Oh, quit complaining about delivery dates! :D It can only come out for the first time once.
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Adamixoye said:
Who is complaining about delivery dates? I have mine.
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I believe I'm the one complaining :-).

I ordered the Iso-Brick a month ago from a local shop and as of yesterday, they don't even have it at their canadian shipping center, so more waiting for me, unfortunately. I don't want to undo the order, I like the guys at the shop but man, this thing is taking forever.... anyhoo, worst thing in life than waiting for a glorified battery... :-)
 
#105
Dave W said:
Every time I check in on this thing the dates are pushed further and further out. Originally it was shipping in April, then May, June, July, August, and now September. I'll believe it when I see it...
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Do you believe? bass strings online was shipping them last week.
image.jpg
 
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#111
Dave W said:
It's just a standard 2.1mm?
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I believe so. The wall-wart is 18V 2A, and I think it's AC in/DC out but don't quote me on that for sure. There was a discussion of that somewhere, I can't remember if in this thread or somewhere else.
 
#113
nshuman said:
Well, I was thinking a small box that would have transformers in them.

Input would be selectable 110/220v. Output would be 4 18v dc ports with enough juice to run 4 ISO Bricks. And 2x 12vAC outputs to run Mutrons and such boxes. That way I could fit 4 Iso Bricks under my PT-Pro :)
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4 ISO bricks will require 144 Watts of power at 18V! That's going to be a hefty power transformer.

-Frank
 
#116
nshuman said:
If it could power 2 I would be fine as well.
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A lot of the effects that I have seen, that use two wire 12VAC input power, can actually run on isolated 18VDC power.

What they are doing with that 12VAC power inside the effect pedal, is rectifying and filtering it to approximately 17VDC. Then they regulate the 17VDC down to the operating voltage for the circuit. Because the outputs of AC supplies are dependent on the mains voltage, and mains voltage fluctuates from one location to another, there will be a range of output voltages that will be valid for the effect to operate properly. Thus, isolated 18VDC should work fine for most of these units. DC thru a rectifier is still DC. I did this with a 12VAC Alesis rack reverb many years ago.

The only time this would not work, is if they use the two wire 12VAC input power to source another transformer internally for split power supplies or for an internal step-up transformer or capacitor multiplier for HV tube circuits.

If the effect pedal uses a 3-wire AC supply, it will not work. 3-wire AC supplies use the third wire as a center tap connection to the secondary coil of the transformer for generating positive and negative operating voltages for the circuits.

But if you still wanted 12VAC on your pedal board, you could use an inexpensive 90W 18VDC laptop supply to feed your two MXR ISO's and also feed small 18VDC to 12VAC inverter circuits. The inverter circuits would be much cheaper to build than what a hefty transformer would cost and you can isolate them from each other. You could also have the DC to AC inverter be able to run at selectable frequencies (like 50Hz to 200Hz).

Here is a diagram of what I mean:

Supply idea.jpg




-Frank
 
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#118
boomertech said:
A lot of the effects that I have seen, that use two wire 12VAC input power, can actually run on isolated 18VDC power.

What they are doing with that 12VAC power inside the effect pedal, is rectifying and filtering it to approximately 17VDC. Then they regulate the 17VDC down to the operating voltage for the circuit. Because the outputs of AC supplies are dependent on the mains voltage, and mains voltage fluctuates from one location to another, there will be a range of output voltages that will be valid for the effect to operate properly. Thus, isolated 18VDC should work fine for most of these units. DC thru a rectifier is still DC. I did this with a 12VAC Alesis rack reverb many years ago.

The only time this would not work, is if they use the two wire 12VAC input power to source another transformer internally for split power supplies or for an internal step-up transformer or capacitor multiplier for HV tube circuits.

If the effect pedal uses a 3-wire AC supply, it will not work. 3-wire AC supplies use the third wire as a center tap connection to the secondary coil of the transformer for generating positive and negative operating voltages for the circuits.

But if you still wanted 12VAC on your pedal board, you could use an inexpensive 90W 18VDC laptop supply to feed your two MXR ISO's and also feed small 18VDC to 12VAC inverter circuits. The inverter circuits would be much cheaper to build than what a hefty transformer would cost and you can isolate them from each other. You could also have the DC to AC inverter be able to run at selectable frequencies (like 50Hz to 200Hz).

Here is a diagram of what I mean:

View attachment 680855



-Frank
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That is nice. Frank, do you know if the Musitronics stuff falls in that category? (Old School Mutrons, new Trutrons)?

The 90w laptop supplies would be a good choice. The reality is hat I power about 30-32 devices on top and under my PT-Pro and my fun "shelf" board will have maybe closer to 35. So, 4 ISOs with the wallwarts would be problematic, but two laptop supplies would work more.

Also, the 12v ac stuff I will use is mostly for the shelf board, so I could still just use walwarts there.
 
#119
nshuman said:
That is nice. Frank, do you know if the Musitronics stuff falls in that category? (Old School Mutrons, new Trutrons)?

The 90w laptop supplies would be a good choice. The reality is hat I power about 30-32 devices on top and under my PT-Pro and my fun "shelf" board will have maybe closer to 35. So, 4 ISOs with the wallwarts would be problematic, but two laptop supplies would work more.

Also, the 12v ac stuff I will use is mostly for the shelf board, so I could still just use walwarts there.
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Most of the Musitronics schematics that I have seen are for mains power. So, I can not answer your question without seeing the schematic for the circuit.

If the 12VAC power connection is only two wires, then you can try isolated 18VDC without hurting anything. If there is circuitry in there that needs AC, all that will happen is the pedal will not operate properly.

-Frank
 
#120
boomertech said:
Most of the Musitronics schematics that I have seen are for mains power. So, I can not answer your question without seeing the schematic for the circuit.

If the 12VAC power connection is only two wires, then you can try isolated 18VDC without hurting anything. If there is circuitry in there that needs AC, all that will happen is the pedal will not operate properly.

-Frank
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Cool, Thanks Frank!! I will try with a TruTron when I get one. Those use a 12vAC barrel connector (2 connectors).
 

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