Yeahhhhh, I was wondering if this was coming up soon. I ordered the PPCB board this week, but would love a larger/deluxe version once this is verified. AWESOME!
Why is there 3 dual op amps used when this circuit could have been made using just 2? Is there a difference in performance when only using one side of a dual op amp IC and isolating the other side of each unused channel? Does this technique cause more SAG in the audio path?
It just causes a higher current draw. Maybe the reason was the pcb design. It's a high gain circuit and the physical distance between stages, traces etc might make a difference - prevent oscillation... They could have used TL071, but they might be more expensive than the TL072
Could you please make a smaller version, that fits into a 1590b enclosure? Two opamps are unused, so one TL074 instead of three TL072 would work. And the voltage doubler could be omitted, as most power supplis can deliver higher voltages, if needed.
Seeing as how most of your post comments are requests for other layouts, have you at all considered learning how to draw these yourself? The software that Anders, Sebastian, and I use is a free download that doesn't take very long at all to learn your way around. Google "DIYLC" - and as as always, we are all here to help each other out along the way. Good luck!
Ciao a tutti. Io ho realizzato questo progetto e funziona ma presenta un forte rumore di fondo che è impossibile eliminare. Ho provato in tutti i modi ma non sono riuscito. Ora provo a rifare tutto su un nuovo circuito per capire se precedentemente ho sbagliato qualcosa.
Che tipo di rumore di fondo? Un ronzio, un brusio, uno stridio? Un ronzio basso suggerisce un problema di messa a terra. Uno stridio acuto significa che c'è qualcosa che non va nella pompa di carica. (Prova a cambiare i chip IC.) Buona fortuna!
Grazie Sebastian, ho provato a cambiare chip, sia TL072 che TC1044SCPA ma... il fastidiso rumore basso rimane. Ho ricontrollato tutte le saldature ed eventuali contatti tra le piste facendo passare in mezzo una lama. E' come se l'alimentazione venisse captata nel percorso del segnale.
Frustrante. Non so quale potrebbe essere il problema. L'unico errore che ho notato è che R5 (10k) dovrebbe connettersi al pin 6 dell'IC1, non al pin 7. Forse dovresti controllare che tutti i tagli siano abbastanza grandi?
Ciao a tutti. Finito di assemblare un altro slo ma niente da fare il suono è sovrastato da questo forte rumore di fondo; mi spiace io ci ho provato due volte ma ci rinuncio. Se qualcun altro ha realizzato questo progetto e funziona bene me lo faccia sapere.
Built this and have the same problem as others reported: high-pitched whining that makes it unusable. The circuit does work and I can hear it but the whine is louder than the usable signal. Unverified
Update: I used shielded wire for the input and output jack. It makes the pedal usable at lower gain but the whine comes back once the gain is above 50%.
I'm not sure if this will solve the problem, but sometime I tried it, when the problem is the oscillation (not with the charge pump!).
You could try to make shorter all the tracks with other cut track, if you know what I mean. For example, input stripe R, we can't do too much, but you can interrupt it in R7; C stripe, you can interrupt it in C5 and C8. Every stripes that don't need to be so extended you can make it shorter.
It's just an attempt, some stripe can be more sensitive to pick up noise and oscillation.
OK, so per my previous comment, I tried making this layout and the end result was unusable as oscillations made it unplayable. I ended up buying the PedalPCB circuitboard and building that circuit. Guess what? Oscillations there, too. There were more usable settings but Gain past 9 o'clock and Mids past 12 o'clock were unusable. So I searched the forums and found this thread
1. Wires for IN and OUT need to be routed as per the picture on Page 1. As far away as possible from the board. This is a high gain pedal and those wires are part of the cause of the oscillations. It says that the wires do not need to be shielded but I already had shielded wires connected so I cannot verify that standard wires remove oscillations. Shielded wires definitely do when combined with #2
2. Two component changes are suggested on Page 2. R10, the 1M resistor in the upper left should be changed to 510k. That will eliminate the oscillations. Also, C8, the 100p cap in the upper left should be changed to 220p. That will eliminate the hissing and apparently makes the pedal sound closer to the actual amp.
I made all of these changes in the PCB and all problems re solved. The pedal is usable in all settings of every knob.
Additionally, I also added the Warren Haynes mod which makes the pedal have lower gain when the gain knob is at lower settings. It's an easy mod. You just remove the 1n cap in the upper left - the one between Gain 2 and Gain 3. You can also put the 1n on a DPDT ON/ON switch and connect the middle lugs to the board where the 1n cap should be. That's what I did. It's a lot to shove into a 125B but it fits.
I cannot verify if these changes will work on this layout as I disassembled mine to put the components into the PCB. So hopefully someone here tries it out and can verify.
Correction: The Warren Haynes mod makes the pedal have MORE LOW END when the gain knob is at lower settings. (Not LOWER GAIN like I wrote in the previous comment)
The 1n cap is a bright cap. It filters out low end so the overall tone is brighter. Remove the cap and the low end is added back to the signal making the tone rounder and fuller.
If you are familiar with Warren's tone, it is lower gain but also very full, not bright. When this pedal is set at low gain with the bright cap connected, the tone is very bright. Turn the gain up past 12 o'clock and it's not as bright anymore, so this cap mostly affects the lower gain settings. This mod fixes that problem for Warren. It matters mostly for players who like low gain which I assume is not what most people using this pedal are going for. But I can hear the difference at higher gain also (though it is not as noticeable) and I like having that option to cut the brightness when I feel the need to.
Yeahhhhh, I was wondering if this was coming up soon. I ordered the PPCB board this week, but would love a larger/deluxe version once this is verified. AWESOME!
ReplyDeleteWhy is there 3 dual op amps used when this circuit could have been made using just 2? Is there a difference in performance when only using one side of a dual op amp IC and isolating the other side of each unused channel? Does this technique cause more SAG in the audio path?
ReplyDeleteI saw that and was so confused too. Why not just use both channels or sub singles instead? It seems like it's a waste of an op amp.
DeleteIt just causes a higher current draw. Maybe the reason was the pcb design. It's a high gain circuit and the physical distance between stages, traces etc might make a difference - prevent oscillation... They could have used TL071, but they might be more expensive than the TL072
DeleteI like to trace the layout, and this seems ok.
ReplyDeleteI find weird, too, the unused half dual op-amp. And a bit about the two 22nF in parallel: why not just one 47nF?
R5 10K connects to pin 6 of IC1, not pin 7.
ReplyDeleteCould you please make a smaller version, that fits into a 1590b enclosure? Two opamps are unused, so one TL074 instead of three TL072 would work. And the voltage doubler could be omitted, as most power supplis can deliver higher voltages, if needed.
ReplyDeleteSeeing as how most of your post comments are requests for other layouts, have you at all considered learning how to draw these yourself? The software that Anders, Sebastian, and I use is a free download that doesn't take very long at all to learn your way around. Google "DIYLC" - and as as always, we are all here to help each other out along the way. Good luck!
DeleteHoney, I've been building pedals and drawing my own layouts for twenty years. I just don't have the time anymore
ReplyDeleteBuy the PCB
Deletehttps://www.pedalpcb.com/product/pcb596/
Aww. You called me "Honey" - that's the nicest thing anyone has said to me all week.
DeleteI wasn't asking for help, folks. I just suggested a simplified version of a great pedal.
ReplyDeleteHas this been verified?
ReplyDeleteCiao a tutti. Io ho realizzato questo progetto e funziona ma presenta un forte rumore di fondo che è impossibile eliminare. Ho provato in tutti i modi ma non sono riuscito. Ora provo a rifare tutto su un nuovo circuito per capire se precedentemente ho sbagliato qualcosa.
ReplyDeleteChe tipo di rumore di fondo? Un ronzio, un brusio, uno stridio? Un ronzio basso suggerisce un problema di messa a terra. Uno stridio acuto significa che c'è qualcosa che non va nella pompa di carica. (Prova a cambiare i chip IC.) Buona fortuna!
ReplyDeleteThis comment has been removed by the author.
ReplyDeleteGrazie Sebastian, ho provato a cambiare chip, sia TL072 che TC1044SCPA ma... il fastidiso rumore basso rimane. Ho ricontrollato tutte le saldature ed eventuali contatti tra le piste facendo passare in mezzo una lama. E' come se l'alimentazione venisse captata nel percorso del segnale.
ReplyDeleteFrustrante. Non so quale potrebbe essere il problema. L'unico errore che ho notato è che R5 (10k) dovrebbe connettersi al pin 6 dell'IC1, non al pin 7. Forse dovresti controllare che tutti i tagli siano abbastanza grandi?
DeleteCiao a tutti. Finito di assemblare un altro slo ma niente da fare il suono è sovrastato da questo forte rumore di fondo; mi spiace io ci ho provato due volte ma ci rinuncio.
ReplyDeleteSe qualcun altro ha realizzato questo progetto e funziona bene me lo faccia sapere.
Built this and have the same problem as others reported: high-pitched whining that makes it unusable. The circuit does work and I can hear it but the whine is louder than the usable signal. Unverified
ReplyDeleteUpdate: I used shielded wire for the input and output jack. It makes the pedal usable at lower gain but the whine comes back once the gain is above 50%.
DeleteI'm not sure if this will solve the problem, but sometime I tried it, when the problem is the oscillation (not with the charge pump!).
DeleteYou could try to make shorter all the tracks with other cut track, if you know what I mean.
For example, input stripe R, we can't do too much, but you can interrupt it in R7; C stripe, you can interrupt it in C5 and C8. Every stripes that don't need to be so extended you can make it shorter.
It's just an attempt, some stripe can be more sensitive to pick up noise and oscillation.
if compare with https://dirtboxlayouts.blogspot.com/2021/02/modern-slo-100.html
ReplyDeletejfet j201 who has sound better?
This comment has been removed by the author.
ReplyDeleteOK, so per my previous comment, I tried making this layout and the end result was unusable as oscillations made it unplayable. I ended up buying the PedalPCB circuitboard and building that circuit. Guess what? Oscillations there, too. There were more usable settings but Gain past 9 o'clock and Mids past 12 o'clock were unusable. So I searched the forums and found this thread
ReplyDeletehttps://forum.pedalpcb.com/threads/lead-solder-overdrive.20717/
There are two things useful in there.
1. Wires for IN and OUT need to be routed as per the picture on Page 1. As far away as possible from the board. This is a high gain pedal and those wires are part of the cause of the oscillations. It says that the wires do not need to be shielded but I already had shielded wires connected so I cannot verify that standard wires remove oscillations. Shielded wires definitely do when combined with #2
2. Two component changes are suggested on Page 2. R10, the 1M resistor in the upper left should be changed to 510k. That will eliminate the oscillations. Also, C8, the 100p cap in the upper left should be changed to 220p. That will eliminate the hissing and apparently makes the pedal sound closer to the actual amp.
I made all of these changes in the PCB and all problems re solved. The pedal is usable in all settings of every knob.
Additionally, I also added the Warren Haynes mod which makes the pedal have lower gain when the gain knob is at lower settings. It's an easy mod. You just remove the 1n cap in the upper left - the one between Gain 2 and Gain 3. You can also put the 1n on a DPDT ON/ON switch and connect the middle lugs to the board where the 1n cap should be. That's what I did. It's a lot to shove into a 125B but it fits.
I cannot verify if these changes will work on this layout as I disassembled mine to put the components into the PCB. So hopefully someone here tries it out and can verify.
Correction: The Warren Haynes mod makes the pedal have MORE LOW END when the gain knob is at lower settings. (Not LOWER GAIN like I wrote in the previous comment)
ReplyDeleteThe 1n cap is a bright cap. It filters out low end so the overall tone is brighter. Remove the cap and the low end is added back to the signal making the tone rounder and fuller.
If you are familiar with Warren's tone, it is lower gain but also very full, not bright. When this pedal is set at low gain with the bright cap connected, the tone is very bright. Turn the gain up past 12 o'clock and it's not as bright anymore, so this cap mostly affects the lower gain settings. This mod fixes that problem for Warren. It matters mostly for players who like low gain which I assume is not what most people using this pedal are going for. But I can hear the difference at higher gain also (though it is not as noticeable) and I like having that option to cut the brightness when I feel the need to.