I've tried to find a decent demo of this filter mod. Seems any of the demo's on YouTube dont really sound all that different to me. We could really use a good schematic pic of this mod.. isnt it basically a switch to choose one or the other outputs of the filter chip? --- In korgpolyex@yahoogroups.com, "AARON" <aaron3900@...> wrote: > > Alright, disregard what I said below about the inferiority of the 12db filter. I got the two mixed up. > > When I wired up the mod, I jotted down some notes about which color wire I attached to which pin. But when I wrote down the values of the pins, I reversed them. So I thought 24 was 12, and vice versa. > > I can't believe how much better the 12dB filter sounds. Really amazing! > > Aaron > > > --- In korgpolyex@yahoogroups.com, "AARON" <aaron3900@> wrote: > > > > So, just to be on the safe side, I did replace that polarized cap that I installed last night with an NP cap -- again, to be consistent with the original design. > > > > I've got to say that I'm less than impressed with the 12dB mod. To my ear, it sets a lower cutoff frequency or something. Seems like the brilliant highs are missing. I hear more subtlety in 24dB mode. I think Korg got it right when it chose this over 12dB. > > > > Just one man's opinion.... > > > > aaron > > > > --- In korgpolyex@...m, "AARON" <aaron3900@> wrote: > > > > > > Hi Mike, > > > > > > Yes, I noticed that it was non-polarized when I was taking it out last night. > > > > > > I assume that Dave came to that conclusion that it's a polarized cap because the PCB has a "+" where one of the leads solders into the board. But from the standpoint of wiring up the 12/24dB mod, the distinction is important, I think, because if you take the other lead -- the "negative" one -- and wire that one up to the switch, it won't work. So I guess he means simply that the lead that's stuck into the hole marked "+" is the one to use. > > > > > > By the way, I replaced C103 with a polarized cap last night (soldering the positive lead into the hole marked "+" on the board), and everything's working fine. I guesss whether you use a polarized or non-polarized cap really isn't critical here. > > > > > > Aaron > > > > > > --- In korgpolyex@yahoogroups.com, Michael Hawkins <korgpolyex800@> wrote: > > > > > > > > C103 is a non polarised electrolytic cap. It is not polarised and does not have a + or - pin. I am not sure how Dave came to the conclusion that the cap has a positive and negative side. But it doesn't. > > > > > > > > Mike > > > > > > > > > > > > > > > > ________________________________ > > > > From: AARON <aaron3900@> > > > > To: korgpolyex@yahoogroups.com > > > > Sent: Monday, November 12, 2012 2:25 PM > > > > Subject: [korgpolyex] Re: Schema for 12/24 dB filter cutoff slope mod: new file (JPG) and photo uploaded > > > > > > > > > > > > Â > > > > Hi all, > > > > > > > > I'm a new member here, but certainly not new to the Poly 800 (I own two) or modding (I've done the Moogslayer mod on one of my machines). > > > > > > > > I'm glad I found this particular thread. Before I became a member today, I found a 2003 thread regarding this mod by doing a Google search. It said to use the NEGATIVE lead of C103. > > > > > > > > So last night, I excitedly got to work on the mod, wired it up exactly as instructed and got ... well, a big bunch of nothing. No sound at all. So, I had to replace C103 with a new 10uF cap (since I'd already cut the negative lead loose from the board), and the synth now works again. > > > > > > > > Tonight, I'll try 'er again with the revised instructions. I may just replace C103 with a 10uF axial-lead capacitor (soldering in just the negative lead, of course) to make the job a bit easier. I'm eager to hear how this mod sounds! > > > > > > > > Cheers to Dave for sharing the revised info (in 2007). > > > > > > > > Aaron > > > > > > > > --- In korgpolyex@yahoogroups.com, "Dave Bowman" <davidmochen@> wrote: > > > > > > > > > > Hi all, > > > > > > > > > > Having been requested by a member of this NG to provide some details > > > > > about the 12/24 mod (which of course I didn't happen to create, but > > > > > nevertheless managed to implement succesfully), I just uploaded a jpg > > > > > file to the Files section and a photo to the Photos section in my > > > > > album (Dave's Poly 800). > > > > > > > > > > I hope this may be of help, since the mod's description featured in > > > > > an older post, though useful, unfortunately has a mistake as regards > > > > > the C103 capacitor's polarity. > > > > > > > > > > I performed the mod exactly as is described in the pic/file, and it > > > > > works fine. > > > > > > > > > > Sorry for the spellcheck lines under the words... I created the > > > > > schematic using Microsoft Word and forgot to turn the autospell > > > > > feature off... it's late here in Argentina and I should collapse in > > > > > bed right now! > > > > > > > > > > Cheers, > > > > > > > > > > Dave > > > > > > > > > > > > > > >
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Re: Schema for 12/24 dB filter cutoff slope mod: new file (JPG) and photo uploaded
2012-11-13 by bimmerfan222
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