Amiga 1000 Audio Filter Disable Hack

[Hook]

I didn't record a video of the before and after but I did extensively compared the A1000's audio with my A1200 by playing the same mod file and switching inputs on my amplifier to compare.

Before the mod, higher frequency notes weren't very crisp and almost sounded muffled. The difference is very noticeable with the mod and I love that the power LED goes dim, giving you visual confirmation that the mod works. It almost look like it was an implemented feature that they left out. Really pleased with the end result.

[MBry0]

I've just made the last proposed mod, and it works as expected.
It's really like putting cotton out of ears.

[jdryyz]

The power LED will dim when the filter is disabled?? I figured it would be the other way around. I know there is a similar behavior with the A500's power LED but I do not recall what the pattern is.

I only just recently hooked up the audio cable to my A1000 that I obtained a while back and immediately recognized that something wasn't quite right. Hmmm... yeah, it was the filter. I had forgotten about that. Also absent from my memory was the it is not switchable in software. The hardware mod led me here.

I was leaning toward the switchable version but now I am thinking when would I ever want to apply the filter?

Anyway, if the power LED is dimmed with the filter disabled, I might not be able to notice the power LED is there at all when enabled since it seems so dim to begin with.

I didn't record a video of the before and after but I did extensively compared the A1000's audio with my A1200 by playing the same mod file and switching inputs on my amplifier to compare.

Before the mod, higher frequency notes weren't very crisp and almost sounded muffled. The difference is very noticeable with the mod and I love that the power LED goes dim, giving you visual confirmation that the mod works. It almost look like it was an implemented feature that they left out. Really pleased with the end result.

[kinmami]

Hello

Following the ak1.org suggestion, I have designed and implemented the analog switch hack.
https://www.pcbway.com/project/sharepro ... a9ddb.html

It is an adapter board for the CIA and allows using the low pass filter as like as A500, 2000, etc.

[PaulV]

I have a non working A1000 motherboard that has this mod installed - I’m guessing it is another version the low pass filter mod, if so then I’d like to move it over to one of my working A1000.
Question is, has anyone seen this type before? If so any idea how to enable / disable the filter? Or is is permanent mod?