Boss Delay TB Pop

[FlyingZ]

Boss delay pedals DD-3 and DD-5 pop in TB loops for the first 5 or so activations. I tried a 1.5M dropdown at the output but maybe it needs more of a ground. It's is weird that it goes away after being activated several times.

I searched Google for half an hour with no useful results. I was wondering if anyone has implemented a quick fix like bypassing the output mixer or something.

This has been an issue since I can remember so please only reply if you have successfully resolved this exact problem.             DD-3 or DD-5, TB loop only pop,  Thanks!

Sorry for my laziness 

[Mark Hammer]

You need a terminating resistor on the input.  Most Boss pedals I've seen have no terminating resistor on the input but do have one on the output.  Their working assumption is that once you plug into their pedal (producing a little thump), all subsequent switching will be done internally via their electronic switching.  Since they assume the input cap will never be lifted from a potential drain-point until you unplug, they don't see a need for a terminating resistance on the input.

If you rehouse such pedals with a TB stompswitch, or even if you leave them in their original chassis and use a TB loop selector pedal to use them, you will experience a pop in exactly the way you describe.  That is, it will pop, but after several on-off cycles, it will have drained off enough via the terminating resistance of whatever is before it, such that there is no audible popping.  Of course, if you use it (i.e., keep it in circuit) for any length of time, then bypass it, when you go to use it again, you WILL hear a pop.

Thankfully, installing a terminating resistor on that input cap solves the problem.

That was easy, wasn't it? 

[FlyingZ]

Thanks! I will try that.  I assumed it was not the problem because other boss pedals do not pop and the only schematic-wise difference is that the delay's outputs are always connected.

Worked! I would never have guessed Boss would skip such a simple fix for a gamebreaker.

[FlyingZ]

Update: Maybe I see why... Added a 10M terminating resistor at the looper send and it added noise.

I'll try terminating in the pedal only next year. These are not pedals I will use live hence my laziness.

[Mark Hammer]

You can't get less "loading" on the input of a circuit than infinite resistance, right?  So Boss had good reason to NOT use a terminating resistor.  At the same time, many of their designs were not, and are not, predicated on people using TB loopers in their pedalboards.  The pedalboard they imagine has a series lineup of nice compact Boss pedals, all left connected to each other all the time.