tag:blogger.com,1999:blog-279251740880432906.post6740348625153474882..comments2024-02-10T20:49:08.923-06:00Comments on Sequence 15: Why does the Juno-60 sound different from the Juno-106?Dave Cornutthttp://www.blogger.com/profile/17769989714705003390noreply@blogger.comBlogger9125tag:blogger.com,1999:blog-279251740880432906.post-71851679155816674972015-10-10T15:59:07.955-05:002015-10-10T15:59:07.955-05:00i think that's right;
hpf 0 is boost
hpf 1 is ...i think that's right;<br />hpf 0 is boost<br />hpf 1 is hpf+original signal<br />hpf 2+3 (just made arbitrary settings for what <br />sounded most effective)<br /><br />looked at all this quite closely for a synthedit <br />project. it sort of worked out ok.(but i used <br />very sharp 'naive' waveforms for the DCO, as the <br />original shape is quite sharp) -you can get quite <br />close to the sound by poking in the right direction <br />and studying the schematics to get an idea of the <br />signal path.<br />what i did wrong was not to have 6x filters+VCAsAnonymoushttps://www.blogger.com/profile/06750270648202353562noreply@blogger.comtag:blogger.com,1999:blog-279251740880432906.post-49710716649888932452010-09-25T19:52:43.528-05:002010-09-25T19:52:43.528-05:00Hey Dave,
You probably know this by now, but the ...Hey Dave,<br /><br />You probably know this by now, but the problem with the 80017A's isn't really that they fail, it's the epoxy coating. I didn't believe this myself, but voices 1 & 3 failed on my 106 and I couldn't get a replacement at that time so I tried it.<br /><br />I removed the 2 failed voices with solder wick very carefully. I've read a better way is to douse the whole track until it's molten solder then simply slide out. I then soaked the 2 voices in acetone for about 3 days (after 1 day I cut away around the sides) and was able to clean off all the epoxy. They now work again as new!<br /><br />The only thing that didn't work out is instead of soldering them back into the board I soldered in some sockets so I can plug the voices. This was a bad idea and they do work their way lose when I move the synth around. Anyway, hope this helps.<br /><br />orpheusAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-279251740880432906.post-26065791218421072862009-02-03T22:27:00.000-06:002009-02-03T22:27:00.000-06:00Here's the page that must have planted the multipl...Here's the page that must have planted the multiple master clock idea in my head:<BR/><A HREF="http://www.electricdruid.net/index.php?page=info.junodcos" REL="nofollow">http://www.electricdruid.net/index.php?page=info.junodcos</A>Unknownhttps://www.blogger.com/profile/03672382980494728368noreply@blogger.comtag:blogger.com,1999:blog-279251740880432906.post-58150847052574321772009-01-22T19:14:00.000-06:002009-01-22T19:14:00.000-06:00Nice post. I agree with kroffe and think the deta...Nice post. I agree with kroffe and think the details of your interpretation of the 106 position 0 are little off. During position 0 IC4a takes the sum of two things, (1) the unfiltered signal from R25 and (2) the crazy filter signal from R24.<BR/><BR/>Here's what's happening in the crazy filter: Stage 1 consists of C8, C9, and R22. You are right that C8 is connected to ground and will filter out high frequencies, but high frequencies will also pass through C9 without much impedance. If you work out the math Stage 1 has one pole and one zero. High frequencies begin to roll off because of the pole but then the response flattens out at higher frequencies because of the zero. So Stage 1 is a bass boost. Stage 2 consists of R18, R19, R20, C6, IC4b. It is really just an active version of Stage 1 with the same type of frequency response. See "adding bass boost circuit" <A HREF="http://ta2020.huuryuu.com/usbDAC_e.html" REL="nofollow">here.</A><BR/><BR/>The combination of the two stages has two poles and two zeros. The two poles cause the roll off to be steeper and the two zeros flatten the response out at higher frequencies.<BR/><BR/>Adding the unfiltered signal to the crazy filter signal still gives a two pole bass boost but with shifted frequencies. I guess this gave better design flexibility or let them use smaller caps. I'm not sure.<BR/><BR/>I agree that it is a bass boost circuit and it sort of looks like a Sallen Key filter, but I don't think it technically is.DustySchematicshttps://www.blogger.com/profile/11887331591538517928noreply@blogger.comtag:blogger.com,1999:blog-279251740880432906.post-623953824710876522008-10-30T04:44:00.000-05:002008-10-30T04:44:00.000-05:00great post guys!Gr,VCA Examengreat post guys!<BR/>Gr,<BR/><A HREF="http://www.vcadirect.nl" REL="nofollow" TITLE="VCA Examen">VCA Examen</A>Unknownhttps://www.blogger.com/profile/14480434577027430223noreply@blogger.comtag:blogger.com,1999:blog-279251740880432906.post-84321733625939500712008-10-18T22:13:00.000-05:002008-10-18T22:13:00.000-05:00I absolutely think it would be possible, if someon...I absolutely think it would be possible, if someone was designing a DCO polysynth from scratch. I'm not sure about modding an existing Juno-60 or 106, but I won't say it isn't doable. However, I have another approach I might try someday. I've always wanted to pull the ROM from the module board, extract the code, disassemble it, and see about doing mods to the firmware. If I do, one thing I plan to add is an offset table that will add a small, randomly-chosen offset to each voice. That would eliminate the "perfect" intervals between voices, and unison mode in particular would sound a heck of a lot better.Dave Cornutthttps://www.blogger.com/profile/17769989714705003390noreply@blogger.comtag:blogger.com,1999:blog-279251740880432906.post-81957941835485972382008-10-16T20:56:00.000-05:002008-10-16T20:56:00.000-05:00I don't have a 106, but was surprised at how close...I don't have a 106, but was surprised at how close the 60 sounds to the jp4. <BR/><BR/>Apart from the the HPF and the envelopes, oh ok and the chorus... but the basic tone is ridiculously similar.<BR/><BR/>Playing chords immediately differentiates them, as the JPs oscs each tune differently.<BR/><BR/>After reading your other article on <A HREF="http://sequence15.blogspot.com/2008/02/analyzing-juno-106-dco-circuit.html" REL="nofollow">Juno DCOs</A> the idea of multiple master clocks (one for each osc) seems too delicious to ignore.<BR/><BR/>Do you think it would be possible?Unknownhttps://www.blogger.com/profile/03672382980494728368noreply@blogger.comtag:blogger.com,1999:blog-279251740880432906.post-73182666971090175552008-10-16T10:14:00.000-05:002008-10-16T10:14:00.000-05:00I actually wasn't totally sure which caps were doi...I actually wasn't totally sure which caps were doing what in that part of the circuit. But yeah, I think the combination of C8 and IC4b are providing bass boost, with the rest of the signal going through unaltered -- there isn't any actual high pass in this part of the circuit.Dave Cornutthttps://www.blogger.com/profile/17769989714705003390noreply@blogger.comtag:blogger.com,1999:blog-279251740880432906.post-28914925940670034702008-10-16T04:08:00.000-05:002008-10-16T04:08:00.000-05:00Very nice and comprehensive runthru the Juno-60 an...Very nice and comprehensive runthru the Juno-60 and 106. I already knew about the 80017A and all that, but the exact function of the HPF had slipped my mind..:)<BR/><BR/>However, your quote:<BR/>"To me, the biggest difference is in the configuration of the filters, with the 106 providing one "high pass" position which is actually low pass."<BR/><BR/>I percieved the circuit for position 0 on the 106 as both straight signal (R25) AND bassbosst (IC4b), but I guess that's what you meant?<BR/><BR/>Thanks for the effort of writing it down anyway! ;)<BR/><BR/>/kroffekroffehttps://www.blogger.com/profile/12640763093165434219noreply@blogger.com