FET DI enabled/disabled From Toggle Switch?

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Shadow777
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FET DI enabled/disabled From Toggle Switch?

Post by Shadow777 »

Hi Joe, I have built the Group DIY EZ1290 dual preamp and I have no room on the front panel for 2 guitar inputs. Is it possible to change the auto switching on the FET DI kit so that it can be used on the back of my rack enclosure and selected between DI and MIC by a mini toggle on the front panel? I have also installed the "Go Be tween"(s) as well. Thanks so much, Chris

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Re: FET DI enabled/disabled From Toggle Switch?

Post by Joe Malone »

Shadow777 wrote:Hi Joe, I have built the Group DIY EZ1290 dual preamp and I have no room on the front panel for 2 guitar inputs. Is it possible to change the auto switching on the FET DI kit so that it can be used on the back of my rack enclosure and selected between DI and MIC by a mini toggle on the front panel? I have also installed the "Go Be tween"(s) as well. Thanks so much, Chris
YES Easy. See attached images below.
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Joe :-)
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Shadow777
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Re: FET DI enabled/disabled From Toggle Switch?

Post by Shadow777 »

Thanks Joe. Hey what would be the difference between the fet and the op amp versions? Why would some one choose one over the other? Thanks

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Re: FET DI enabled/disabled From Toggle Switch?

Post by Joe Malone »

Shadow777 wrote:Thanks Joe. Hey what would be the difference between the fet and the op amp versions? Why would some one choose one over the other? Thanks
Both sound the same. As in add no tone. Just pure unity buffer.

The differences are

The OPAMP DI version can run on as low as 12v power rail and has no relay to drive as the switching is in the jack. Can only mount on up to a 3mm panel and the jack nuts can strip if over tightened.

The Fet DI can only run as low as 24v. Has to have a 2k7 resistor shorted out to do this so the relay still works. Can mount on up to a 5mm panel and jack is very strong.

The FETDI is recommended for all new builds.

New FET DI Ver2 has RC input filter to stop radio/mobile interference as well.
Joe :-)
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Shadow777
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Re: FET DI enabled/disabled From Toggle Switch?

Post by Shadow777 »

Hi Joe, The DI's had arrived and I finally got them built and installed in my ez1290. I'm having a problem though with getting them to work. When I have only the Go betweens hooked up with the plastic jumpers and no DI's, the preamp's, pad, phantom, etc all work fine. But when I go to hookup the DI's and insert the ribbon cables, there is no guitar audio and even when I close the circuit as described in your earlier post, I get no mic audio as well. Its like the DI's are just shutting everything down. The DI's are receiving exactly 48 volts supplied by the Go betweens so power doesn't seem to be an issue. I'm just not sure how to diagnose them. Your help would be greatly appreciated. Thanks, Chris

Shadow777
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Re: FET DI enabled/disabled From Toggle Switch?

Post by Shadow777 »

I just noticed something on the DI's PCB....do I have to physically jumper the two spots under the IC's?
Thanks again

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Re: FET DI enabled/disabled From Toggle Switch?

Post by Joe Malone »

Shadow777 wrote:Hi Joe, The DI's had arrived and I finally got them built and installed in my ez1290. I'm having a problem though with getting them to work. When I have only the Go betweens hooked up with the plastic jumpers and no DI's, the preamp's, pad, phantom, etc all work fine. But when I go to hookup the DI's and insert the ribbon cables, there is no guitar audio and even when I close the circuit as described in your earlier post, I get no mic audio as well. Its like the DI's are just shutting everything down. The DI's are receiving exactly 48 volts supplied by the Go betweens so power doesn't seem to be an issue. I'm just not sure how to diagnose them. Your help would be greatly appreciated. Thanks, Chris
Have you made up the ribbon cables correctly with pin 1 (triangle on connector) red strip on ribbon both ends?

Does the Go between kit have 0v audio / power supply wired to it?

Otherwise attach here or send me some photos of the modified Di and ribbon cables and wiring to the Go between kit so I can check them over.
Joe :-)
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Re: FET DI enabled/disabled From Toggle Switch?

Post by Joe Malone »

Shadow777 wrote:I just noticed something on the DI's PCB....do I have to physically jumper the two spots under the IC's?
Thanks again
What version of DI kit do you have? Or do you mean the 2 jumpers that are fitted if no relay if fitted?

Since you need to switch DI/MIC you will still need to fit the 10 pin relay the correct way around for the switching to work.
Joe :-)
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Shadow777
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Re: FET DI enabled/disabled From Toggle Switch?

Post by Shadow777 »

Have you made up the ribbon cables correctly with pin 1 (triangle on connector) red strip on ribbon both ends?

Does the Go between kit have 0v audio / power supply wired to it?

Otherwise attach here or send me some photos of the modified Di and ribbon cables and wiring to the Go between kit so I can check them over.
I believe I made them up with the correct orientation...Red stripe was on the left side but orientation of the connectors were as in your stock photos.
I have version 2. I was looking at the pcb you had posted in the beginning of this thread and noticed the two jumpers under the relay. I had missed that but wandered if I needed to go back and solder in some jumpers?
"Does the Go between kit have 0v audio / power supply wired to it?"
The Go between is wired like your directions the 3 pins of the input xlr are feeding it and its output to transformer.A + 48 volt line is going to the 48volt green input and the - is going to the 0 volt green input. I hope this makes sense... Thanks again

Shadow777
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Re: FET DI enabled/disabled From Toggle Switch?

Post by Shadow777 »

Also I removed the two pins per your directions and soldered in a switch to your specified location. thanks

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Re: FET DI enabled/disabled From Toggle Switch?

Post by Joe Malone »

Shadow777 wrote:Also I removed the two pins per your directions and soldered in a switch to your specified location. thanks
Can you hear the relay click when you switch the external DI/MIC switch?

When the switch is on the mic input should be working?

Does phantom power LED on the go between light up when 48v switch is on?

You did send me any photos of the Go between wiring and ribbon cable?
Joe :-)
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Shadow777
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Re: FET DI enabled/disabled From Toggle Switch?

Post by Shadow777 »

Can you hear the relay click when you switch the external DI/MIC switch?

Does phantom power LED on the go between light up when 48v switch is on?

You did send me any photos of the Go between wiring and ribbon cable?
I'll have to check that, as I didn't really hear any clicking that I was aware of.
Yes phantom led comes on and will power a mic perfectly. I'm also measuring 48v at the input of the DI.
Just sent some. The input xlr is feeding as your diagram, as is the 48v. The output of the go between sends out hot and cold and the green wire you see in the photo goes to the shield through on the input transformer.
As a side note, The negative of the 48 volt power supply feeding the go between is also going to the 0 volt of the green connector.

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Re: FET DI enabled/disabled From Toggle Switch?

Post by Joe Malone »

Shadow777 wrote:
Can you hear the relay click when you switch the external DI/MIC switch?

Does phantom power LED on the go between light up when 48v switch is on?

You did send me any photos of the Go between wiring and ribbon cable?
I'll have to check that, as I didn't really hear any clicking that I was aware of.
Yes phantom led comes on and will power a mic perfectly. I'm also measuring 48v at the input of the DI.
Just sent some. The input xlr is feeding as your diagram, as is the 48v. The output of the go between sends out hot and cold and the green wire you see in the photo goes to the shield through on the input transformer.
As a side note, The negative of the 48 volt power supply feeding the go between is also going to the 0 volt of the green connector.
The ribbon cable is wrong. It has the GO Between end on backwards. Red strip is going to pin 10 on the go between connector and pin 1 on the DI connector.

Pin 1 is the square pcb pad under the PCB and is marked on the PCB header by a triangle.

With the ribbon cable plugged in at both ends the 48v rail should be shorted out completely.

Fix the ribbon cable end at the go between by reversing it and you should be working.
Joe :-)
JLM Audio
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Shadow777
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Re: FET DI enabled/disabled From Toggle Switch?

Post by Shadow777 »

Wow, so all I have to do is say...flip the cable over 180% on the DI side and re install the connector to the cable, plug it in and go? Too cool. I'll do this tonight. Thanks so much Joe!

Shadow777
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Re: FET DI enabled/disabled From Toggle Switch?

Post by Shadow777 »

Hi Joe, I reversed the ends on the ribbon cables as you said and walla! it came to life! The DI's and custom switch work excellent. Thanks so much for your direction on this! Chris

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