Connect 8-preamp via line cable instead of adat

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Connect 8-preamp via line cable instead of adat

Post by wearashirt »

Is it "OK" to connect an external 8-preamp (Presonus Digimax D8) to an audio interface via line-cable? The line cable is a generic "low noise oxygen free" cable and the connectors will be 1/4 mono jacks. To illustrate, the cable makes electric guitars sound a lot brighter than usual marketed guitar cables. Should I use something like a Mogami cable to connect a preamp to a A/D converter?

This is instead of an ADAT-in option, which my audio interface does not have. This way, I can also sample at 96khz, instead of the maximum 48khz of the 8-preamp.

Is the internal audio circuit path in an interface significantly greater than any external cabling can achieve? How are traditional (expensive) preamps led to converters?
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Re: Connect 8-preamp via line cable instead of adat

Post by resistorman »

Any decent cable will do fine, there are no "magic cables" :mrgreen: Use balanced wiring if possible.
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Re: Connect 8-preamp via line cable instead of adat

Post by Wonks »

Passive guitars are high-impedance sound sources, and a guitar amp has a high impedance input. This makes the cable length and capacitance have an audible effect on the guitar (or bass’s) sound.

Line outputs are much lower impedance outputs and the driving circuitry isn’t affected by typical guitar cable lengths, so any reasonable quality cable will do.

But your line outs and interface line ins will be set up for balanced cable operation, so you are best using 1/4” TRS to 1/4” TRS cables. TS to TS cables should be OK over short distances but you’ll only have an unbalanced connection, so they won’t have the noise rejection that you get when using TRS cables which allow balanced operation.

(Balanced and unbalanced operation is primarily dependent on the output and input circuitry. A TS cable can force unbalanced operation on an otherwise balanced circuit but TRS cables themselves can’t make an unbalanced circuit balanced.)

So in an emergency use TS cables on balanced connections if you need to, but TRS are always better.
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Re: Connect 8-preamp via line cable instead of adat

Post by ef37a »

https://www.gear4music.com/Recording-an ... 7qEALw_wcB

The above would be a much tidier solution than 8 entangled (they always do!) cables.

As Wonks says, go balanced if you can and cables are agnostic when output impedance is low, below 1000 Ohms is fine for short domestic runs,but that ADAT pre amp is even lower than most at 51 Ohms.

You don't say what the interface is so I cannot comment on possible level problems but with the ADAT unit delivering just +10dBu at 0dBFS I doubt there will be any.

Dave.
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