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I have a black label CE -2, serial number 0000 on the bench. I can't get this thing to stop ticking both on and off. The ticking changes with the rate and increases with the volume. I've read up a lot on this issue and it sounds like it is a common problem. I've replaced all the power supply caps. The only thing left are the 1uf caps. I've checked the caps that I have pulled and they all test okay. ESR checks good on the remaining 1uf's. Surely they didn't let this thing leave the factory with this issue so I'm struggling to figure out what to fix. Since this is such an early model I hesitate to mod it. I may try to add shielded cable to the rate pot. Others have said this helps. Thoughts or suggestions?
Last edited by tdlunsfo; 04-13-2019 at 05:52 PM.
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That's it. It actually works fine and sounds decent, minus the ticking.
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Just realized I posted this within the amp forum. Mods, can you move this to effects?
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I have a black label CE -2, serial number 0000 on the bench. Pedal works well but has a ticking on or off and also notice a volume loss when comparing the pedal in and out of the chain. I've replaced all the power supply caps. The only thing left are the 1uf caps. I've checked the caps that I have pulled and they all test okay. ESR checks good on the remaining 1uf's. Surely they didn't let this thing leave the factory with these issues so I'm struggling to figure out what to fix. Weak chips? I may try to add shielded cable to the rate pot or Mark's mod with the resistor on pin 6 of the LFO. Any other thoughts or suggestions?
Last edited by tdlunsfo; 04-14-2019 at 02:44 PM.
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Does the ticking rate correspond to the modulation speed setting?
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Changes with the rate pot. I assume that is the modulation speed?
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The dual op-amp handling the LFO duties (IC2A/B) should be a low-current unit, either TL022 or LM358. IF it's a higher-current unit, like a TL072 or 4558 or 5532, it will pull enough current whenever it generates a basic square wave to create a spike in the audio path.
Another approach is that adopted by Boss for the BF-2, which you can read about on page 2 here: http://moosapotamus.net/files/stompb...-mo-tremlo.pdf
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Thanks for the replies. Looks like I have an original JRC4558. Think it's been doing this since it was manufactured? Saw you mention the R and C mod in another forum. Sounds like I may have to go that route. I just hate to modify this thing since it is such an early version.
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Looking at this a little closer and I think I'm more worried about the volume loss at this point. Coming out of the output of the first op amp I am losing almost half of my signal. I am no boss chorus expert but this seems excessive. Any thoughts here? I have some tl022 on order so can try those in place of the 4558 in a few days.
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First is the bias ref set? Upper left VR3. Set so outputs of IC1 are at half its supply voltage. If it is off center, your sweep could be banging the rails.
Does the ticking remain when you turn off the effect for dry pass through? Or only tick when effect is on?
Education is what you're left with after you have forgotten what you have learned.
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The ticking is there with the effect on or off. I did set the bias using the pot but it was days ago. It could've gotten bumped with all the moving around. Will check it again when I get back to it.
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Does it do the 'ticking' with a battery?
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The ticking actually should be there whether the effect is "on" or "off".
LFO ticking occurs because the standard 2-op-amp LFO produces a square wave and then smoothes that out into a triangle for modulation purposes. The initial square wave produces a sudden current draw, which is heard as a spike on the power line shared with any other parts of the circuit, including the audio path.
If it was the case that the CE-2 was true bypassed, then when "off" the straight wire would be unaffected by any nonsense going on with the power line. HOWEVER, the CE-2, like indeed the vast majority of chorus pedals, keeps most of the audio path in circuit, during both bypass and effect modes, and simply uses a single FET to disable the wet signal for "bypass". Any spikes on the supply line are experienced by the dry path as well.
De-ticking such pedals benefits from a multi-pronged approach. One prong is certainly to use a low-current op-amp, like a TL062, TL022, or LM358 - commonly used in such applications - such that the current-draw is reduced. A second prong is to decouple the supply line for the LFO-dedicated chip from the overall supply line. So, normally, the V+ pin (pin 8) of the chip would be tied directly to the 9V supply. To decouple it, one would insert a small-value fixed resistor between pin 8 and V+, like 10-100R, in tandem with a medium-small electrolytic cap value (10-33uf) from pin 8 to ground. Think of the RC combo as being a bit like a micro-battery or pocket money. If what you want to buy is cheap enough, then pocket money is sufficient and you don't have to go to the bank or ATM. If the expense is big enough, though, you DO have to resort to a deeper current-well, like the bank. IOf teh current stored in the cap is enough for the chip to produce that initial square wave, then there is no draw on the overall supply, and no spike/tick produced.
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Yes the ticking was happening battery or power supply. I swapped the 4558 for a TL022 per Mark's instructions and the ticking stopped. I seem to have my volume back as well. Pedal sounds amazing. Thank you all for your suggestions. Now if I could just figure out this Line 6 echo park power problem...
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Great to hear! Or should I say, great to NOT hear?![]()
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