Bluesbreaker Build Report

[Barcode80]

So, three pedals in a week! Now that I've become fairly decent at making PCB's, my output is increasing exponentially! I just put together the Bluesbreaker off the tonepad layout. This thing sounds pretty good! at least good enough that I'm in the process of boxing it right now (pics to come). The distortion is good, if a little less gain than I expected. I'm starting to realize that overdrive is my preferred distortion "type," though, as this type of distortion is starting to sound a little artifical to my ears. But the bluesbreaker is a pleasant surprise. I wouldn't say it would be my top distortion, but it does sound nice to my ears.

I only made one sub, i had no 68k resistors so i used 56k (i think, i'm at work and don't remember too well right now).

Great sounding circuit. I can see the link to blues...

[Hanglow]

I got a pcb from GGG for the bluesbreaker, it's my favourite OD so far. Having said that I've only built a TS clone and the BB  But it is very nice. Goes well with my SS amp as well, the TS less so. I boxed it in an ABS box as I get them free, but will probably put that one into a proper metal enclosure as I know I'll be using it a lot

[markm]

The Blues Breaker is a nice circuit for sure.
It's more OD than Distortion per-se.
Lots of players love the BB.
Congrats!!

[MartyMart]

BB is a good "meat and potatoes" tone to have, I never built one as I have two
originals from the early 90's , moved one on but still use "No 1" quite often

MM

[Barcode80]

hmm. boxed it all up, still sounds great, but there is a HUGE pop when i turn it on. I've already placed a 1M from input to ground, but no luck. thoughts?

[jrc4558]

Check for DC on the output! Sometimes a leaky capacitor does it...

[Fp-www.Tonepad.com]

cool

[Barcode80]

okay this is just odd

so, i tried every anti-pop method i could find in the search. no luck, still pops. not only that, but if i leave the effect of for a few seconds then turn it on, the pop is significantly louder and the signal cuts out for a split second and fades in quickly. anyone experience this before? this is infuriating since the circuit sounded so good before i wired the switch and boxed it. it still does, but that freakin pop is KILLING me.

i tried replacing the .1 uF on the output, no difference. i tried the 2 resistor 1 cap network from jack's site for LED bleed. no difference. i've grounded the effect input on bypass. no difference. i've increased and decreased the pull-down a few dozen times. AAARRRGGGHHH!!!

I really want to put this pedal on the rig, but i can't use it with that pop!

[John Lyons]

If the signal goes away for a second and then comes back it may be an electrolytic cap in backwards.
Take a deep breath and rechaeck everthing with a layout map. Sometimes switches are "poppy" but if the signal is dropping and then coming back up there is something else wrong I believe.

John

[Barcode80]

yeah, i swapped out the switch and it isn't that. I only have on electro in the layout and if i'm reading it right, the neg goes to ground on that cap, which is how i have it. any other ideas? (thanks guys for all your help, i love this place!)

[John Lyons]

How about with the LED disconnected?
Are the pulldown resistors the first and last things in the circuit?
Measure to see if you read DC voltage on the in or output switch lugs when the circuit is bypassed.
John

[Barcode80]

YOWZA! I've got like 7.3 volts on the output lug when bypassed. that can't be good....

[MartyMart]

YOWZA! I've got like 7.3 volts on the output lug when bypassed. that can't be good....

There's your "pop"  source  !!

[Barcode80]

what does that usually mean? how can i fix?

[analogmike]

Your output capacitor is SUPER LEAKY. Replace it and you should be fine.

[Barcode80]

crap, i already replaced it once Okay, i'll give that a shot.

[Barcode80]

okay, i've replaced the input cap,as well as the output cap (twice) and the next cap in the signal path after the input cap. i made a typo earlier, the voltage is on my input lug when bypassed, not the output. it is only there on bypass, which is odd. still getting the pop and the dc on the switch. any other ideas? I'm going to give it a few more debug attempts then i'm either going to put a rat in the enclosure or build a new breaker.

EDIT: oh yeah, i forgot to mention that i took voltages on the IC and all pins except 4 and 8 show about half voltage, 8 show full and 4 shows 0. the only exception is pin 3, which seems to carry a slightly lower voltage than the others. this also makes me think it is at the input, since pin 3 is input (right?).

[Barcode80]

SUCCESS!!! What a dummy! I had the ground from the board connected to the led - which was also connected to ground. problem with that was that the voltage drain from the LED when it shut off got dumped onto the board! pop is gone now... Thanks for all your help!

[Fp-www.Tonepad.com]