Bo Hansen DI layout

[home_listening]

My take on the project - sounds wonderful!

https://fabricastronautblog.wordpress.com/2018/10/15/bo-hansen-di-pt-1/

 

[Whoops]

Looks Great, Congratulations.

 

[Newmarket]

Nice Work.
I think I'd make the end pies metal though (I assume they are 'wood' from the photos) and I'd recommend using the optional screening cans on the transformers.

 

[home_listening]

Nice Work.
I think I'd make the end pies metal though (I assume they are 'wood' from the photos) and I'd recommend using the optional screening cans on the transformers.

Hi, thanks.

I mentioned it in the article I linked to - the wooden panels were filling up an unrelated 3mm lasercutting order and just for the prototype. The Vigortronix transformers are also just to test the board at low cost. Finished versions will have aluminium panels and Lundahl LL1538 transformers fitted.

 

[Newmarket]

Hi, thanks.

I mentioned it in the article I linked to - the wooden panels were filling up an unrelated 3mm lasercutting order and just for the prototype. The Vigortronix transformers are also just to test the board at low cost. Finished versions will have aluminium panels and Lundahl LL1538 transformers fitted.

Ahh I see. I skimmed the article but obviously missed that.  I thought the end panels looked really good - better than I'd do for a 'fill in'  Will be interesting if you let us know what you think wrt the Lundahl vs Vigortronix for your use.
I took a more 'basic' approach and built a non-phantom power single channel on Stripboard using the OEP tx option using an electrical 'adaptable box' for the enclosure.  Sounds good but doesn't have the aesthetic appeal of yours 

 

[TannerS14]

Hey guys, just finished up my DI box, had a blast doing the project, kinda tuckered out tho lol. Did a 3d printed base with a metal top/ sides. The design isnt perfect but if anyone wants to mess around with the file/ print one for themselves they're welcome to it.

- https://drive.google.com/file/d/1CiA3byx_J0Xf0Hm7-X1cy9g0alGtXzpR/view?usp=sharing

Included in the link is 3d cad file if anyone wants to modify it, and multiple 3d print file formats. Just hand the file to whoever and have them print. (Note every printer is different, so printer accuracy is important if you dont want to have to modify it, as i had to since i had it printed on a low end DIY machine a buddy had).

Any thoughts on how well certain 3d printed plastics would act as an insulator? Would we be able to run metal jacks and rely on the body to insulate? Not a big deal but i feel like metal jacks would be kinda neat. If anyone has a high quality jack that they like/recommend i might get around to modifying the file to fit those.

Unfortunately,  the issue i was trying to combat still persists with this DI box, though I think it is functioning correctly via voltage checks. Im still clipping my interface even with the level all the way down- (7 string guitar, A-Tuning, Passive pups, rewired with pots removed).  My interfaces' mic pre has a gain range of + 16db to +60db, unless im interpreting the specifications of my interface wrong, that means my guitar could be close to clipping the DI box @ 19db if its clipping my interface @ 16db. I've ordered an attenuator barrel to see if bringing the level down before the interface resolves my issue and allows my guitar plugins to function properly. That being said it is an extremely quite device with or without the guitar plugged in. Thanks to bo and everyone in this thread!

Edit. Attenuation barrel brought the level down, but i still dont have any life in the guitar tone regardless of levels of the plugin unless i turn the mic pre up to where its clipping, then the life comes back into the tone a bit but its clipping lol. Not understanding what's going on here. I guess I'll try to get a new interface, maybe an audient id4, not really sure.

 

[Mmt50816]

Posting on here is a first for me.

I have built 2 of the DI boards from 51xaudio

Both boxes worked and sounded fantastic using the 1538XL transformer. Recently one of the boxes has experienced very significant volume drop. The 24v and 12v test points described on Bo's website both still test correctly and the LED turns on.  I only own a multi meter, no scope so I cant really trace anything.

Any tips on trouble shooting would be appreciated

 

[Jarno]

Any thoughts on how well certain 3d printed plastics would act as an insulator? Would we be able to run metal jacks and rely on the body to insulate? Not a big deal but i feel like metal jacks would be kinda neat. If anyone has a high quality jack that they like/recommend i might get around to modifying the file to fit those.

Unless you are using very high voltages, that PLA definitely is an insulator, feel free to use metal jacks.

 

[[silent:arts]]

Recently one of the boxes has experienced very significant volume drop.

Look for bad solder joints at the transformer, and the 10µF electrolytic.

 

[TannerS14]

Thank you Jarno! I think i will probably re-design the box and maybe do a high quality print with some metal jacks and see how it works.

It seems my issue with the interface was from low quality mic pre-amps of the unit (UR22 V1). Against my better judgement i bought another interface, and my guitar is sounding the best it ever has through sim plugins! I got a little audient ID4. I compared the built in Jfet converter vs the Bo hansen and it definitely has an edge over the instrument input on the device. Super happy and i can FINALLY trust that i have a solid guitar DI i can rely on and not feel like i have to re-do takes because of DI quality. Such a great feeling! I've been struggling with this for sooo long and knew there was an overall signal quality issue, really glad i didnt just accept it. Thanks again to everyone here.

 

[Cade Allen]

Hey all!

Just finished up my DI build. I connected it to my Focusrite 2i2, engaged phantom power, and nothing.

Any ideas? It's not in an enclosure yet, so that could be affecting it in some way but there isn't any audio passing through - I'm trying it out with my Fender Jazz bass. If I tap on the PCB, I can hear it through the output but nothing else is coming through,

Also, the LED is not lit.

Thanks,
Cade

 

[[silent:arts]]

Check your LEDs polarity (or just bridge it to test)
No light = no power for the circuit.

 

[Bo Hansen]

Cade,

The first thing to check is if the LED is lit, and if it is turned in the right direction as mentioned earlier.

If you have a multimeter and can use this, you should check out the test points I specify on my DIY / tech page www.hansenaudio.se/techpage.htm

You should also check if you have connect  the cables on the right side of the tele-jacks.

Please attach a clear photo on your mounted circuit board and how all the contacts are wired, so it is easier for us to help you.

—Bo

 

[Cade Allen]

Here are the photos.

https://photos.app.goo.gl/9BzcSx1sb...o don't be too hard on me  ;) Thanks, Cade

 

[Cade Allen]

Measurements:

From the ground on the input jack, to the top 6.8k resistor: 46.2v


This seems to be waaaaaay too high. Maybe I burnt up a resistor or something?  :-\

 

[Treb]

Check the orientation of  BC560C. Are you sure of its base, collector & emitter pinouts?

There might be a cold solder joint. The negative terminal of the 10uF capacitor (the one next to BC550) needs touching up IMO.

 

[Bo Hansen]

Cade,

The pictures are unclear, but I think I see two errors.

1. The BC560 transistor is turned half a turn wrong, so for safety, take a whole new transistor when you correcting it.

2. The input jack you show in the picture, you have connect the cables on the wrong side, the signal breaks when you insert the plug.
Check if you made the same mistake on the output jack.

The inut jack should also be chorted to ground when the plug is not inserted in the jack. This is what the breakaway connections should be used for.
But note that it should NOT be so on the output jack.

If the DI-box electronics work correctly, you should measure about +24 volts where the two 6.8k resistors are connected together, and also before and after the LED.

—Bo

 

[Cade Allen]

Ok, thanks guys. I'll take a look at it tonight. I appreciate the help!

 

[TannerS14]

You need a piece of metal for the ground, the "chassis" pin on the board at least in your pictures, is not ran to anything. To test this solder a wire into the board and connect it to a piece of metal. Im not mr electronics but it looks like that's whats going on unless im missing something.

 

[Bo Hansen]

This PC card must be mounted in a metal box, and especially in this case where the OEP transformer is used, since it does not have a mu-metal screen.

Of course, the hole/solder connection labeled chassis must be connected to the metal box.

Please note that it is very important to follow the instructions on how to arrange ground between connectors, pc-cards and metal box, that we have discussed lots of times in this thread, and I also write about this on my tech page
www.hansenaudio.se/techpage.htm

—Bo