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June 04, 2023, 02:01:51 AM

Author Topic: Want to add a pre out  (Read 460 times)

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Offline Universe Man

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Want to add a pre out
« on: August 24, 2021, 11:10:19 AM »
I’ve recently finished building my crack, and I am interested in using it as a preamp for my speakers. I was thinking I could just glue a bit of sheet metal with rca jacks in it to the underside of the chassis, and have an rca cable just run under the gap under the wood. I’m just not sure if it’s that simple, and wanted to ask here. What terminals would I need to use? Are there grounding problems or anything like that when using another piece of metal? And do I need any extra resistors or anything like that?

Offline Paul Birkeland

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Re: Want to add a pre out
« Reply #1 on: August 24, 2021, 01:09:36 PM »
Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man

Offline Universe Man

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Re: Want to add a pre out
« Reply #2 on: August 24, 2021, 04:54:59 PM »
I guess I could use that. Would it be a big difference from just using the pre tube?

Offline Paul Joppa

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Re: Want to add a pre out
« Reply #3 on: August 24, 2021, 06:53:22 PM »
The 12AU7 has a fairly high source impedance and can't drive long lines or low impedances by itself.
Paul Joppa

Offline Universe Man

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Re: Want to add a pre out
« Reply #4 on: August 25, 2021, 10:26:48 AM »
Ok