I made a better set of frequency response measurements with the C61 mod. The graph is much clearer in how the deepest bass freqencies are now extended by the removal of C61. If you're interested, you can check it out at:
http://synthhacker.blogspot.com/2013/08/polysix-frequency-response-with-deeper.htmlAlso, you'll notice that the frequency response graph (with or without C61) shows a boost to the high treble frequencies. I mentioned this phenomenon in an earlier post regarding "Korg's Built-In Treble Boost". This new graph doesn't necessarily imply the cause of the boost, but it does very clearly show that a boost exists.
There will be follow up on the treble boost later.
Chip
--- In PolySix@yahoogroups.com, "chipaudette" <chipaudette@...> wrote:
>
> I finally followed-up on Tony's suggestion that C61 on KLM-368 appears to have no purpose and that it could be removed.
>
> When I look at C61, I also see no purpose. I see that it could possible attenuate the lowest bass frequencies. I was curious to see the effect of removing this component. Not wanting (yet) to permanently remove C61, I simply bypassed it with a single clippy jumper wire. Easy!
>
> The result appears to be ~6 dB more of the deepest bass frequencies (down in the 33 Hz neighborhood). That's deep.
>
> If you're interested in the mod, you can check out the details at:
>
> http://synthhacker.blogspot.com/2013/08/polysix-deeper-bass-bypass-c61.html
>
> If you've got good headphones or really good speakers, there's also an audio comparison.
>
> My conclusion is that maybe the Polysix doesn't need these super-deep frequencies. It is a fun change, but I'm not sure it's how I want it to sound all the time. I'll have to live with it for a while before I make my decision.
>
> Thoughts?
>
> Chip
>