DSM OmniCabSim

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Re: DSM OmniCabSim

Postby Anjang » 29 Jan 2019, 10:12

its work for Guitar and Bass ??
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Re: DSM OmniCabSim

Postby J0K3RX » 29 Jan 2019, 21:08

Anjang wrote:its work for Guitar and Bass ??


http://www.youtube.com/watch?time_conti ... lBLAt-1bq4
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Re: DSM OmniCabSim

Postby temol » 02 Feb 2019, 19:59

What's the proper wiring of the GND lift with balanced output? Simple swith disconnecting pin1 from GND is good enough? I've also seen R and C in a different configurations along with a switch.
gnd_lift.jpg


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Re: DSM OmniCabSim

Postby Dsmnoisemaker » 02 Feb 2019, 20:52

I used both..both works..I think the one with the cap and resistor is more "legal" :D
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Re: DSM OmniCabSim

Postby temol » 04 Feb 2019, 22:25

Thank you for the reply Daniel.

Here is my version of the sim, boxed and almost ready (I have to wire GND switch) .

IMG_9100_600.jpg
IMG_9101_600.jpg
IMG_9102_600.jpg


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Re: DSM OmniCabSim

Postby Dsmnoisemaker » 05 Feb 2019, 02:55

Be aware that some xlr jacks will have a chassis ground connection which will defeat the ground lift.
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Re: DSM OmniCabSim

Postby lukatosh » 11 Feb 2019, 01:50

Hi Daniel, Lucas here...from Chile. (Escribo en inglés por si alguien más se anima a responder).

may i ask some questions about your design?

What about using phantom power?

What would be the values of the resistor and capacitor in the "ground lift" arrangement? Different values are used on different schematics even when (apparently) they do the same function.

what about the power rating of the resistor? Here i'm looking at a PCB of a preamp that has XLR out and there is a 49R9 resistor (SMD) tied to pin 1 of the XLR jack

http://sound.whsites.net/p35-f2.gif
http://www.hansenaudio.se/Active%20DI%20box%201975.jpg
http://www.hansenaudio.se/Active%20DI-b ... ematic.png
https://i.warosu.org/data/diy/img/0008/ ... 357746.gif
https://www.prosoundweb.com/images/uplo ... igure6.jpg


Muchas gracias!!
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Re: DSM OmniCabSim

Postby plush » 11 Feb 2019, 10:07

lukatosh wrote:
What about using phantom power?



Hi Lukatosh

Based on my experience, most phantom power sources do not provide enough power for your preamps/cabsims to operate properly.

Resistor+cap @ ground lift is essential if you are using phantom power. Total ground lift will basically remove ground connection and phantom power won't work.
Knowing, that there should be DC signal path, the resistor must be of pretty low value, ~10-100R. Cap usually ~100n.
The purpose of the resistor is to lift the part of the circuit, preventing stray currents, which are pretty low at this point. Very typical implementation, changing the values won't make much difference.
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Re: DSM OmniCabSim

Postby temol » 12 Feb 2019, 12:00

Here is the build document for the BAJA version of the Omnicabsim - omnicabbaja-xlr_build_doc.pdf

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Re: DSM OmniCabSim

Postby Ben N » 13 Feb 2019, 14:09

I see the space advantage of using a pair of quads, obviously, but it seems to me that NE5532 would make more sense for outputs--single, balanced or headphone. Given that this puppy may well be last in a signal chain before amp/pa/desk/interface, it ought to have a little line driving oomph.

BTW, Daniel, that 2015 video is of this version, right? Because, whatever its limitations, it sounds mega. :applause:
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Re: DSM OmniCabSim

Postby Dsmnoisemaker » 13 Feb 2019, 17:19

Yes is that version..:)
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