DI Box?

[jman 31]

Hey guys I have a question regarding DI Boxes. I have been reading that in order to make a recording quality DI Box that a Jensen transformer in the order of $70.00 usd would be the way to go.

I am not looking to go through a snake with my guitars or anything. I primarily just want to go from an unbalanced guitar jack to a balanced XLR jack. Is there a cheaper solution that would give me the same quality? Is there a simple way to achieve this without the transformer?

I would also need to take into account the impedance issues because I want to go into the mic input on a mixing board.

Thanks
Jeremy

[Nigel Goodwin]

Just buy an active DI - they sound excellent, and match far better than a transformer - transformer 1Meg input, 600 ohm output?, I don't think so

I use cheap Behringer twin DI boxes, I've used them on bass and guitar, both passive and active, and everytime they sound really great.

As far as I'm concerned the only advantage of a transformer is that it provides a true break for earth loops, but that doesn't apply for a guitar anyway.

[Minion]

You can make an active DI pretty easy useing a Fet Opamp buffer and a DRV134 Ballanced line driver chip or simular...

Cheers

[jman 31]

Originally posted by Nigel Goodwin
Just buy an active DI - they sound excellent, and match far better than a transformer - transformer 1Meg input, 600 ohm output?, I don't think so

I use cheap Behringer twin DI boxes, I've used them on bass and guitar, both passive and active, and everytime they sound really great.

As far as I'm concerned the only advantage of a transformer is that it provides a true break for earth loops, but that doesn't apply for a guitar anyway.

I will look into those. I really would like it to run on phantom power if I use an active DI. I need to check if that is one of their options.

Minion, I don't know the ins and outs of designing circuitry. Have you seen a schematic for one that is good enough to use for a recording studio?

Jman

[jman 31]

What do you guys think about this circuit? It's an active, phantom powered DI box that has an in and an out. Will it be quiet enough to record with?

I also found this one but it is not phantom powered.
http://www.diyfactory.com/projects/c...ountryhick.htm

Thanks
Jman

[Nigel Goodwin]

Originally posted by jman 31

I will look into those. I really would like it to run on phantom power if I use an active DI. I need to check if that is one of their options.

The Behringer I use can be powered by a 9V battery, or by phantom power from the mixer. It's the DI20, twin channel, I've found them invaluble (I even bought a second one as I liked it so much ). Only £20, not worth messing about building one.

http://www.bluearan.co.uk/index.php?...&img_name=DI20

Everyone should have one in their bag!.

As for the single transistor circuit, it's really pretty naff - it isn't going to be very good quality.

[jman 31]

Originally posted by Nigel Goodwin


The Behringer I use can be powered by a 9V battery, or by phantom power from the mixer. It's the DI20, twin channel, I've found them invaluble (I even bought a second one as I liked it so much ). Only £20, not worth messing about building one.

http://www.bluearan.co.uk/index.php?...&img_name=DI20

Everyone should have one in their bag!.

As for the single transistor circuit, it's really pretty naff - it isn't going to be very good quality.

Thanks man. I will probably go that route. I like doing diy projects, but this one wasn't really grabbing my attention anyways. I appreciate your time.

Jman