Condor Cab Sim with XLR out?

Started by jimosity, August 18, 2010, 01:03:26 AM

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jimosity

What is the best way to implement an XLR output in the Condor Cab Sim?
Specifically please.
Jim Rodgers
jim@americanhc.com

jkokura

By building a DI box probably. I'm assuming you want to route it to a soundboard right? In order to use the Mic inputs of a sound board, you have to change your signal to the line level that a mic cable accepts - usually that's done by using a DI box. (Direct Injection Box)

There's two ways to do it: Buy it or Build it. If you want to build one into a box along with the Cab Sim, I recommend checking out these: http://www.jensen-transformers.com/as/as007.pdf and http://www.jensen-transformers.com/as/as066.pdf

If you want to buy one, i highly recommend Radial DI's. Based on my experience with live sound, I really like them. There are other cheaper alternatives, but the Radials sound really good to my ears. I have a/b'd them on keyboards and acoustic guitars, in both cases I closed my eyes and picked the Radial as sounding better. I like the JDI's and have one in my own gear.

Jacob


jimosity

So basically - just wire in an XLR jack without a transformer, huh?
I was under the impression that I would need some kind of transformer in there to change impedence or something
Jim Rodgers
jim@americanhc.com

B Tremblay

Check out the circuit linked in this post (the rest of the thread may be useful as well):
http://www.diystompboxes.com/smfforum/index.php?topic=49154.msg365330#msg365330
B Tremblay
runoffgroove.com

jimosity

I hate to bring this topic back after so long, but it's still something I've not quite ironed out and want to make sure that I'm doing the right thing here.

I want to build a cab sim with an XLR output, so I've read thru two different responses and I want to be sure that I choose the right method.

Mark Hammer had replied in another thread with this to say about needing an XLR on a higher output device (higher than normal mic outputs)
QuoteThe thing to recall about balanced lines is that they are fundamentally a solution for keeping noise at bay in low level mic signals.  Your average passive dynamic mic doesn't put out nearly as big a signal as a guitar, and traditionally it often had to run very great lengths to get to the PA.  The output impedance of the mic was low enough that cable capacitance and treble loss would not be a big issue. However, with that length of cable (think Bob Hope wandering about with a handheld mic on stage in Viet Nam entertaining the troops on a 60ft wide stage with a PA parked somewhere way off to the side), the odds are pretty good that noise would be accumulated between the mic and PA input.

That's the benefit of balanced lines.  If any noise is picked up along the way, it is shared in common between the two hot leads, and cancels out at the mixer input.

So why am I telling your this?  Because if you're going to run a hot output (and all the circuits mentioned in this thread are bloody hot compared to an SM58n or Radio Shack "highball" mic) for a grand length of a couple of feet, the odds of accumulated noise getting in there and needing balancing to cancel it out are pretty damn slim.

Make no mistake, balanced lines ARE useful and important, just not so much in this instance.  Indeed, a standard mono phone plug, wired up to two pins on an XLR plug is probably all you really need.  I may be wrong, but my gut sense is that you can worry about this much less than you're currently doing.

I read from that the I don't really need anything more than a jumper from my 1/4" outs to the appropriate pins on an XLR jack to give it the connection needed.
is that accurate?

Part two of my uncertainty is if I need an audio isolation transformer.
How do I *KNOW* if I need one?
If so, I have some 42TM018 audio transformers.
Are some of the schematics for DI's on the Jensen site good for use with this transformer or is there a suggestion for a simple DI circuit that I can use?
Jim Rodgers
jim@americanhc.com

jimosity

Jim Rodgers
jim@americanhc.com

euronymous0001

what i did was condor>h&k red box mkII, no transformers used and has XLR out