Question regarding circuit sword and stereo sound

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andershp
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Question regarding circuit sword and stereo sound

Post by andershp » Mon Apr 29, 2019 2:59 am

I know the original GB only had 1 speaker, but the jack outputs stereo, and I guess the circuit sword does too.

Is it possible to somehow solder a second speaker onto the circuit sword, maybe place it in the cartridge bay or something, to have stereo sound in a build, or does the circuit sword only support monoural output with one speaker?
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kite
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Re: Question regarding circuit sword and stereo sound

Post by kite » Mon Apr 29, 2019 4:54 am

The CS (and CSL) outputs stereo to the headphone jack (and enabled as such that you always hear stereo). When the headphones are not plugged in, it creates a mono summing circuit, which mixes stereo in to mono, this is then fed in to a mono amp and then to the speaker. This means that when you plug headphones, full stereo! When you are using without, you still get both channels, but from the one speaker, so you're never just "listening to one channel" in any configuration.

Because there is only a mono amp on the board, it is a lot of effort to undo the mono summing circuit and wire in your own stereo amp. It is possible, but it's a lot of effort to SMD parts!

Hope that helps

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andershp
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Re: Question regarding circuit sword and stereo sound

Post by andershp » Tue Apr 30, 2019 5:20 am

Thanks for the thorough answer.
I was not suspecting it to cancel one of the channels, just checking to see if soldering another speaker onto it would open up for stereo effects in games.

Never mind, I won't dive into this sort of advanced modding - the circuit sword is so neatly packed with optimized goodness, and these kinds of changes will not end up being pretty, I think :D
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bailsone
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Re: Question regarding circuit sword and stereo sound

Post by bailsone » Wed Sep 15, 2021 11:50 am

Hey i read that the CS is summing up the stereo signal to a mono channel for the speaker in case no headphone is connected. somehow this doesnt work for me in Zelda for SNES when standing on the right side of the screen i cant hear FX sound like the sword or a bomb do i miss sonething in the configuration for this stereo to mono conversion ? any help is apreciated Thanks.

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