NOTE: My Twin Famicom has the correct resistors for R103 and R104 even in stock. This video does not show audio distortion from swapped resistors.

Tracks used: "Ground BGM" - Super Mario Bros., "Title BGM" - The Legend of Zelda (FDS), "Beginning" - Akumajou Densetsu

I recapped my Twin Famicom back in late October. Besides that, I also made a few adjustments for the audio output.

Removed C205 low-pass filter cap on the AV/Power Board. (Removes muffling)
Replaced R201 from an 8.2K resistor to a 2.2K resistor. (Increases volume level output)
Replaced R125 from 22K to 20K resistor.
Replaced R103 from 2.2M to 2M resistor.

Doing the latter two makes the audio mixing closer to an original Famicom and Famicom Disk System.
Guide: https://nerdlypleasures.blogspot.com/2018/01/famicom-nes-simple-tweaks-to-restore.html

3 points xxxxDREADNOUGHT

That sounds great, did you post a video on YouTube of you doing this or have a guidethat you worked form? I would love to do this to my Sharp Twin Famicom too

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1 points itmustbeyzzy

I followed this: https://nerdlypleasures.blogspot.com/2018/01/famicom-nes-simple-tweaks-to-restore.html?m=1

Also here's the location of the cap and resistors (pics are from my Twin Famicom): https://imgur.com/a/UrzUREM

I'm currently experimenting with replacing C205 with an 820pF film capacitor instead of leaving it disabled just to see how much the LPF affects the audio, as I find the audio to be slightly overdriven compared to a regular Famicom and FDS.

(Stock C205 value is 22nF.)

I chose 820pF value based on this OLD guide: http://vaot.mydns.jp/fc/tfaudio.htm

YMMV if you want to replace C205 with a lower value or leave it empty.

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3 points empinatepues

I also had my twin famicom audio fixed. big difference

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1 points deepthawnet

AN-505 (twin fami turbo) doesn’t have this issue (or at least it’s not as bad) right?

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2 points PowerPie5000

My AN-505BK sounds perfectly fine and clear to my ears and I remember it sounding a bit better/louder than my original Famicom. I had to change the mic capacitor in the controller with my OG Famicom though as it used to create a bit of audio interference (buzzing). I'll give them both another listen at some point.

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