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jugglindan
20-04-2020, 07:55 AM
With all my pedal building madness, I have realised that my core tone is not as bright and sparkly as it could/should be (comparing guitar straight into amp vs via pedal chain with all pedals off). The general opinion is to put either a buffered pedal or buffer first in the chain. My first pedal is a tuner which is sadly true bypass.

Which leads me to the baffling conclusion that the answer to tone issues caused by too many pedals is to build another pedal!

Fortunately I already have everything I need to build a stripboard Little Black Buffer (https://tagboardeffects.blogspot.com/2014/05/jhs-little-black-buffer.html) :)

jugglindan
20-04-2020, 09:09 PM
Not as much detail required for this one. Wired it in one session, and the build went more smoothly than the Barber clone (I must have learned something on that). Still waiting for the op amp to arrive so I can test before boxing it up. Given it's a buffer that I built while watching Buffy (it's easy to watch without paying too much attention), I am thinking some sort of Vampire Slayer theme for the enclosure.
34616
Nothing to it, just that board, 2 guitar jacks, a power jack, an LED and a 1590a enclosure. All up around $12 in parts (and $9 is the 1590a). And that sells for $130 plus postage.

jugglindan
21-04-2020, 08:54 PM
Drilled the enclosure and did the external wiring. Substituted a 4558D for the TL072 (since they haven't arrived yet). Hooked up for a test before final boxing:
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Works great!

Everything was smooth sailing to this point, but after boxing all I got was static that went away when I touched the enclosure. There is so little room in the 1590a enclosure that the output jack was shorting against the case. There followed some fun times with insulation tape and jack position adjustments, but after 4 or 5 attempts I got it sorted. And this pedal doesn't even have pots or a footswitch. Conclusion, I hate building in these small cases!

34631

Just a couple of finishing touches to go. Some waterslide decals and a clear coat, a bezel for the LED (currently held in place by tape), and a better way to hold the board in place. I tried a small strip of hook and loop tape (the kind used on pedalboards) to hold the board to the underside of the case lid. But the adhesive won't stick to the board.

jugglindan
21-04-2020, 09:22 PM
Mock decal:
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jugglindan
25-04-2020, 06:56 AM
The real decals are on (a bit different to the mock), and a layer of clear coat is over the top. Was just ready to box it up when the clear started flaking off. It totally failed to bond to the white powder coat underneath. Oh well, live and learn. Now I can't decide whether to box it anyway, or scrape all the clear off, probably losing the decals in the process, then lightly sand the powder coat and start again. Or maybe SCA clear acrylic won't bond to the powder coat at all.

McCreed
25-04-2020, 07:41 AM
I don't think I've ever sprayed over powder coating before, so I can't offer any advice there. You would think they'd get along okay though. (?)

The enclosures I've refinished (just for a custom look, like the Caline pedals) I stripped bare and primed. Then just used duplicolor for base coat. I prefer the Septone Clear, so that's what I used. I think I've used White Knight Clear Acrylic on pedals too. Haven't had issues with either of those adhering.

All the other pedal enclosures I've done have been bare metal off the shelf.

Maybe Andy40 will pop in with advice.

jugglindan
25-04-2020, 08:02 AM
Yeah, all my bare metal enclosures have worked fine with SCA primer, Duplicolor (OD-2) or SCA colour (#5) then decals and SCA clear. It's just the powder coated one that has failed. I bought it thinking it would make things simpler but maybe not. I think sanding might help once I scrape off the old stuff.

jugglindan
25-04-2020, 08:55 AM
to start again or not, that is the question:
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I think I will start again, just for the learning experience. I printed extras of the decals just in case I screwed up somewhere. I will try sanding with 320. Or I could go back to bare metal ...

jugglindan
25-04-2020, 05:13 PM
Well, I changed my mind once again due to a combination of laziness, the desire to move on to other projects, and the fact that mixed in to my pedal board I probably won't notice the chipped clear coat. Once(if?) the decals start showing damage I might refinish then.

Final boxing:
34700
I have started using small pieces of stripboard to mount the LED and current limiting resistor and to provide solder pads for the wires. It works really well and lets me use the left over bits of board. The foam I am using here is packing material from some bathroom taps I bought last year. It's the perfect density and thickness to hold the board in place and to insulate the solder side from the lid.

All plugged in, works great (in that buffer sense of "I can't hear any difference"). I have to rebuild my pedalboard before I can comment on it's buffering properties.
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McCreed
25-04-2020, 06:54 PM
Is that font from Buffy The Vampire Slayer? And that little monster on the side from the production co? (or whatever they show at the end)

I used to have an MI Audio Boost 'n' Buff, and it definitely made a difference in the tone. It was pretty big, like 5 meg or something.

I have since ditched that and switch to all low capacitance guitar and pedalboard leads. I do have at least one buffered bypass pedal (sometimes two) on my board, and I get plenty of sparkle in my tone. I've never run huge lengths anyway, but switching the leads between the pedals made the biggest difference. Previously I had a hodge-podge of DIY and manufactured patch leads that were stupid high capacitance.

Now I make all my own guitar leads with Van Damme cable. It's great stuff with a capacitance of 26 pF/ft.
For my pedals I've gone to all Lava Cable solid core which is 32 pF/ft. No problem with high end loss.

jugglindan
25-04-2020, 08:27 PM
Haha, yes, it's the Buffy font (or rather a free interpretation (https://www.1001fonts.com/rebuffed-font.html)). I have been rewatching Buffy while building pedals in the evening. It works because I know the stories so well I don't need to pay too much attention. The mock decal just had the letter B but I switched to "Buffer" when printing the decals. "Buffer the Capacitance Slayer" was too much text to fit nicely. I might try for that if I ever redo the finish.

I only have one buffered pedal and it's too far along the signal path. Plus my patch cables are a motley assortment. Even a long chain of true bypass pedals can mess with the signal a bit. Before building this I did an A/B test - guitar direct into amp vs guitar through pedal board with everything off.

I wonder if I can measure my lead capacitance with my multimeter? ...

jugglindan
25-04-2020, 08:42 PM
Ok, I measured some of my leads:
cable from guitar to pedal board: 51pF/ft, 9.8ft so 500pf total
my old patch cables: 73pF/ft
some new ones I haven't installed yet: 81pf/ft

Ouch!

But at least I have a buffer :)

Andy40
26-04-2020, 04:20 AM
I need to do this. All my pedals are true bypass

McCreed
26-04-2020, 07:08 AM
Good stuff JD!

I used to think the cable capacitance thing was a load of tone snob hooey until I did the same A/B test... and wow! I immediately bought a buffer!

And once I started measuring the capacitance of my various (and pre-historic) cables... lots got the plug chopped off and cable chucked in the bin. This is also when I decided making 100% of my own cables was the best option.

Here's a great video by Canadian guitarist Pete Thorn (great player btw) that demonstrates the effect cable length has on tone.
The best part is the result is shown electronically (?) not just by the human ear.


https://www.youtube.com/watch?v=YOWeoizp4y0

jugglindan
26-04-2020, 07:54 AM
Thanks for the video link. I like Pete Thorn, he has a great way of explaining technical topics from a guitarists perspective. That's the longest I have seen his hair though!

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jugglindan
26-04-2020, 06:43 PM
Just did a bit of minor surgery to this pedal. The tagboard layout called for a 470r current limiting resistor for the LED. I thought that was a bit low so used a 680r. But the LED was still far too bright. Desoldered and replaced with 2k2. Now it's just right.

Also found this video from That Pedal Show. It's pretty much the same as the Pete Thorn one, but longer, slower, and with more detail. I like how they start with a description of a guitar tone control and then use that to explain the effect of signal chain capacitance.

https://www.youtube.com/watch?v=JSWqLuXUfnY

jugglindan
30-04-2020, 08:04 PM
And this pedal is done. It now has a permanent home as first in line on my board.

jugglindan
02-05-2020, 10:16 AM
How do you know when a buffer is working?

All your EQ settings are now too bright.

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McCreed
02-05-2020, 10:32 AM
How do you know when a buffer is working?

All your EQ settings are now too bright.

I presume you've done A/B testing. I would imagine "chalk and cheese" comes to mind ;).

I was bowled over by the difference when I was running my Boost 'n' Buff. A real eye opener.

jugglindan
02-05-2020, 11:12 AM
I presume you've done A/B testing. I would imagine "chalk and cheese" comes to mind ;).

I was bowled over by the difference when I was running my Boost 'n' Buff. A real eye opener.A/B testing (direct to amp vs through bypassed pedals) is why I built the buffer. But my amp EQ was set for the pedal board and now I am rolling guitar tone back 50%.

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McCreed
02-05-2020, 03:00 PM
A/B testing (direct to amp vs through bypassed pedals) is why I built the buffer. But my amp EQ was set for the pedal board and now I am rolling guitar tone back 50%.

Do you reckon your new compressor is adding to that difference?
I know mine adds "sparkle" FLOABW, but it also 3 adjustable parameters Comp, EQ, Volume. (just like the original Diamond)

jugglindan
02-05-2020, 03:22 PM
Do you reckon your new compressor is adding to that difference?
I know mine adds "sparkle" FLOABW, but it also 3 adjustable parameters Comp, EQ, Volume. (just like the original Diamond)It's not the compressor. Too bright with it off. In fact, the compressor warms things up a bit, feels like it is squashing a little too much. I will have to pull out the multimeter to adjust some more. I might try the voltage setting your Greek pedal builder uses.

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