AC/DC coupling [thread moved]

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tranzfuse
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AC/DC coupling [thread moved]

Post by tranzfuse » Sat Aug 28, 2010 8:06 pm

Hi, sorry to cut in, but I'm trying to wrap my head around some of these terms and concepts you're talking about.

What is AC-coupled vs. DC-coupled?

I'm barely a newbie, I appreciate your knowledge and insight.

Thanks!

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os
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Post by os » Sun Aug 29, 2010 3:25 am


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Post by tranzfuse » Sun Aug 29, 2010 9:33 am

That was a nice Sunday morning read! Way to get the gears turning for sure, now I need coffee.

I noticed in a previous comment this was said:
What's your audio interface?

If it's AC-coupled, are you using the AC Encoder plug-in?
Does this suggest that different manufacturers may choose to use either AC- or DC-coupling when designing an audio interface? Or is one of these a standard? I have a MOTU Ultralite for example.

Thanks again.

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Post by tuj » Sun Aug 29, 2010 10:44 am

yes, most but not all interfaces are ac-coupled. you can search through this sub forum for your specific interface.

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Post by os » Sun Aug 29, 2010 1:33 pm

The Ultralite is DC-coupled, which is why it's not so important to have something like the ES-1 for it.

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Post by tranzfuse » Mon Aug 30, 2010 10:50 pm

os wrote:The Ultralite is DC-coupled, which is why it's not so important to have something like the ES-1 for it.
OK, so does that mean I would need the special 'floating ring' cables you've mentioned before to interface between Ableton <-> MOTU <-> Modular? I believe I read on another thread that these special cables can be purchased for $100 for 8 (Sly Goose was it)?

And I'm still in the middle of researching, but is a MIDI/CV gate module required in the above scenario? Or is MOTU enough?

Thanks again.

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Post by baltimoroder » Tue Aug 31, 2010 12:13 am

MOTU strongly recommends "lifting the ring" to avoid damaging the interface when passing DC but some people have been ok with regular TRS-TS cables. You can also use commonly-found 1/4" to 1/8" Insert Cables FWIW.

Silent Way uses your computer to generate CV; no MIDI-CV interface necessary. Your Ultralite will generate around 7V on the main output and 9V on the headphone output.
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Post by tranzfuse » Tue Sep 21, 2010 12:51 pm

baltimoroder wrote:MOTU strongly recommends "lifting the ring" to avoid damaging the interface when passing DC but some people have been ok with regular TRS-TS cables. You can also use commonly-found 1/4" to 1/8" Insert Cables FWIW.

Silent Way uses your computer to generate CV; no MIDI-CV interface necessary. Your Ultralite will generate around 7V on the main output and 9V on the headphone output.
Hey guys,

I'm still researching some things and trying to better understand some details I've come across.

It seems to be that the advantages of using an ES-1 with a MOTU Ultralite interface are:

1. A centralized panel to manage patching from MOTU -> modular
2. Up to 9x greater voltage output

The second point I don't fully understand. If it is being mentioned as a benefit, so I assume more voltage output is good. Why exactly?

As baltimoroder mentioned above, the MOTU outputs around 7v from the main outputs. Is this sufficient? Is this miserable? Is this awesome?

And I assume voltage output ties in to the 1v/octave measurement I keep reading about.

And if there are just over 7 octaves on an 88 key piano, wouldn't the MOTU's output of 7 volts have me covered for that octave range? I'm guessing there is more to this equation than I realize.

Thanks everyone.

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Post by os » Tue Sep 21, 2010 1:26 pm

The Ultralite mk3 generates about ±3.5V. The range of voltages in a Eurorack system is usually ±10V, so there's definitely a shortfall.

±3.5V is a range of 7V, but only 3.5V of it is positive. Depending on what it's connected to that can be significant. E.g. some old synths need +10V or more to trigger a gate.

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Post by tranzfuse » Thu Sep 23, 2010 8:22 pm

os wrote:The Ultralite mk3 generates about ±3.5V. The range of voltages in a Eurorack system is usually ±10V, so there's definitely a shortfall.

±3.5V is a range of 7V, but only 3.5V of it is positive. Depending on what it's connected to that can be significant. E.g. some old synths need +10V or more to trigger a gate.
OK, thanks for the clarification. It is beginning to make a little more sense.

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