OKAY! Built!!! Works and sounds AWESOME! However - J175 jfets are DGS, not DSG. I went ahead and did the layout as you drew it, and tried out just about every jfet I have with that pinout. The octave down is apparently GREATLY affected by that bit, so the one I settled on was a BF245C. I twisted the legs on a J175 to see if it would work, and it did, however, the octave would cut out whenever I would dig into the strings. Also - TL062s work fine but tracking is WAY better with TL072s. Like almost digital/POG tracking perfect. Way better than I would expect from a 4013. This is an awesome circuit and is going on my board as soon as I box it up!
I test my builds with a baritone guitar tuned to B Standard. Also I must mention, sockets on all the ICs are worth it. Had to try a couple flip flop chips and dual op amps (settled on a mix of 4558s and TL072s) too. This effect is unity gain but tracks better than any analog circuit I've built so far.
I built it and it works but somewhat weak...tried the suggestions Chris made above and it is better but not powerful enough. And, there is no difference when I remove IC4... still sounds the same, could that be a hint to the weakness?
I could use some help. I built this following Chris’s suggestions except I only used TL072s as I was not sure what order the different ICs would go in. It sounds good and tracks really nice.
The problem I am having is when I turn it on only the dry signal comes through, then I have to play pretty hard for the octave to kick in (like it’s gated and needs the volume to hit a certain threshold to activate) After that it works really good as far as I can tell (I’ve never actually used an octave before) But after awhile if I play to fast or hard or a combo (haven’t quite figured out the cause) the octave cuts out again and I have to repeat the process.
The two things I know is 1: that I accidentally connected the power in reverse at first but it was only -0.03v thanks to the Schottky. I looked up the ICs and Transistor and they should be fine. 2: this was my first strip bored project (second pedal build) I needed to extend the border so I staked another piece over lapping with row Z but I for got to add the cuts to the lower level of strip board. I realize now that I could have just butted them together and the components would keep it together.
Would greatly appreciate any help! (I’m pretty green at all this) Thank you.
sometimes when i experience that i really have to play very very hard, it turns out i had a bad (cold) solder, or wrong connection, so double check all your solders, check for jeff bridges! and check that your wires are connected at the correct points. ( i have not build this one (yet)
I have looked over the solder joints and connections and they all looked good, but it doesn’t hurt to triple check. I will look over it again and maybe I should go ahead and fix the over lapping strip board. Thank you for such a fast reply!
with layouts as large as this one it is best to get larger stripboard ( which is not fun since it is much more expensive) but then again, buying the effect itself is akways more expensive then buying larger stripboard!
Also - may I commend your bravery for choosing something as large and relatively complicated as this for your first strip build. I think my first was the tagboard layout of the original Interstellar Overdriver. Building on this stuff can be fraught with errors - some that may be practically invisible. A tiny fleck of copper left on a cut or a minuscule solder bridge can wreck the functionality of the circuit. Don't give up! Getting one of these designs to work is an achievement and totally worth multiple attempts!
I had no J175s!!! However, they just showed up yesterday so...
ReplyDeleteBuilding this one up now. Haven't fired it up yet. But you should update the layout to say "51 cuts, 31 links"
ReplyDeleteOKAY! Built!!! Works and sounds AWESOME! However - J175 jfets are DGS, not DSG. I went ahead and did the layout as you drew it, and tried out just about every jfet I have with that pinout. The octave down is apparently GREATLY affected by that bit, so the one I settled on was a BF245C. I twisted the legs on a J175 to see if it would work, and it did, however, the octave would cut out whenever I would dig into the strings. Also - TL062s work fine but tracking is WAY better with TL072s. Like almost digital/POG tracking perfect. Way better than I would expect from a 4013. This is an awesome circuit and is going on my board as soon as I box it up!
ReplyDeleteChris! You are awesome, great job and many thanks!
DeleteThe J FET pinout is now corrected (easy fix!) and it is TAGGED.
Did you use it with guitar or bass?
DeleteI built the Multiplexer Octave some years ago, but I never made it works properly (volume and hiss issues).
I test my builds with a baritone guitar tuned to B Standard. Also I must mention, sockets on all the ICs are worth it. Had to try a couple flip flop chips and dual op amps (settled on a mix of 4558s and TL072s) too. This effect is unity gain but tracks better than any analog circuit I've built so far.
ReplyDeleteShouldnt Q1 be DGS for a J175
ReplyDeleteI built it and it works but somewhat weak...tried the suggestions Chris made above and it is better but not powerful enough. And, there is no difference when I remove IC4... still sounds the same, could that be a hint to the weakness?
ReplyDeleteThis comment has been removed by the author.
ReplyDeleteI could use some help. I built this following Chris’s suggestions except I only used TL072s as I was not sure what order the different ICs would go in. It sounds good and tracks really nice.
ReplyDeleteThe problem I am having is when I turn it on only the dry signal comes through, then I have to play pretty hard for the octave to kick in (like it’s gated and needs the volume to hit a certain threshold to activate)
After that it works really good as far as I can tell (I’ve never actually used an octave before) But after awhile if I play to fast or hard or a combo (haven’t quite figured out the cause) the octave cuts out again and I have to repeat the process.
The two things I know is
1: that I accidentally connected the power in reverse at first but it was only -0.03v thanks to the Schottky. I looked up the ICs and Transistor and they should be fine.
2: this was my first strip bored project (second pedal build) I needed to extend the border so I staked another piece over lapping with row Z but I for got to add the cuts to the lower level of strip board.
I realize now that I could have just butted them together and the components would keep it together.
Would greatly appreciate any help! (I’m pretty green at all this) Thank you.
sometimes when i experience that i really have to play very very hard, it turns out i had a bad (cold) solder, or wrong connection, so double check all your solders, check for jeff bridges! and check that your wires are connected at the correct points. ( i have not build this one (yet)
ReplyDeleteI have looked over the solder joints and connections and they all looked good, but it doesn’t hurt to triple check. I will look over it again and maybe I should go ahead and fix the over lapping strip board.
DeleteThank you for such a fast reply!
with layouts as large as this one it is best to get larger stripboard ( which is not fun since it is much more expensive) but then again, buying the effect itself is akways more expensive then buying larger stripboard!
DeleteAlso - may I commend your bravery for choosing something as large and relatively complicated as this for your first strip build. I think my first was the tagboard layout of the original Interstellar Overdriver. Building on this stuff can be fraught with errors - some that may be practically invisible. A tiny fleck of copper left on a cut or a minuscule solder bridge can wreck the functionality of the circuit. Don't give up! Getting one of these designs to work is an achievement and totally worth multiple attempts!
Delete