808 snare PCBs

duff · Post by **duff** » Fri May 23, 2014 1:23 am

Thanks for the info on adding LEDs - I'm a sucker for blinking lights - the ken stone driver looks simple enough to perf board.

duff · Post by **duff** » Fri May 23, 2014 1:23 am

Edit : double post - damn interwebs. That was my 100th too!

falafelbiels · Post by **falafelbiels** » Fri May 23, 2014 5:41 am

duff wrote:Edit : double post - damn interwebs. That was my 100th too!

Will we be seeing a 808 snare PCB set in B/S/T soon?

falafelbiels · Post by **falafelbiels** » Fri May 23, 2014 5:44 am

qp wrote:
duff wrote:How hard would it be to add an led to this such that it lit up when the trigger fires, ideally for both cv and button? Would it be as simple as adding an led and resistor between the trigger pad on the front panel board and ground?
You'll need a transistor and a couple resistors for that. Ken Stone's LED driver works great. I've used it in several designs. You can also sub the 547 for a 3904, but the pinout is swapped if I remember correctly.

Also, you would rather connect that LED driver to the output of the module is my guess. Maybe tap it form the envelope driving the noise VCA. Now where the hell is that on the PCB eh?

Try one of the two spots in yellow circles.

rosch · Post by **rosch** » Fri May 23, 2014 9:16 am

soo, i would say it sounds good with the 2N3904 B and C pins swapped.

but i'm not sure if it functions quite right. well i haven't tried adjusting the trimmer yet but here's what it does for now:
trigger and external trigger work fine.
the snappy pot seems to dampen the signal, kind of like a low pass filter, tune works like i would expect it.
the accent pot actually seems to set how much of the noise is coming in, i.e. if i turn it all the way up, at a certain level the noise is always present while i can trigger the rest of the sound.

i will make a short video later tonight to show how it works!

falafelbiels · Post by **falafelbiels** » Fri May 23, 2014 9:21 am

I know how to fix this and will be posting about that tonight. I need my laptop online for that, right now I'm on my phone...

Edit: actually it is very easy; on the panelcomponentboard, replace the resitor marked "8k2*" right there in the middle with something a tad higher, say 10k. This sets the upper limit of the lvl control and replacing it should offset the voltage that is on the accent input on the voice board.
Whenever an accent + a trigger signal are applied to the module, +12v (delivered by the and-gate, comprised of the two bc547) is "mixed" with this potential momentarily, making the snare sound louder and harsher.

duff · Post by **duff** » Fri May 23, 2014 9:46 am

falafelbiels wrote:
duff wrote:Edit : double post - damn interwebs. That was my 100th too!
Will we be seeing a 808 snare PCB set in B/S/T soon?

No, one is for my euro, the other is going in a box of drums for my kids to trigger from some home made pads.

I will give those pads a try for the led source. Thanks

rosch · Post by **rosch** » Fri May 23, 2014 10:36 am

alright thanks! i've first tried a 12K then added another 12k in series, that almost got rid of it. so now i subbed the 8k2 with 30k and it works fine as far as i can tell. i'm on +/- 15V maybe that's the reason.

so, it seems like the snappy pot only sets how much noise is permitted to the output? it doesn't seem to affect the tone itself. is that correct?

i'll post a video later, just to see if everything's as it supposed to be
thanks again, sounds great so far!

falafelbiels · Post by **falafelbiels** » Fri May 23, 2014 11:08 am

Yeah +/-15v must be the reason, I designed it for my eurorack so yeah...

The snappy pot determines how much of the trigger signal is used to run the noise VCA/ envelope. So it pretty much determines how much of the noise tail is heard.

falafelbiels · Post by **falafelbiels** » Fri May 23, 2014 11:11 am

duff wrote:
falafelbiels wrote:
duff wrote:Edit : double post - damn interwebs. That was my 100th too!
Will we be seeing a 808 snare PCB set in B/S/T soon?
No, one is for my euro, the other is going in a box of drums for my kids to trigger from some home made pads.

I will give those pads a try for the led source. Thanks

Heh I was referring to the 100 post rule...

Nice that my stuff is used for kiddie drums, I really like that.

Barcode · Post by **Barcode** » Wed May 28, 2014 12:05 am

Arrived in Utah today.

falafelbiels · Post by **falafelbiels** » Wed May 28, 2014 6:28 am

Cool! Took a while though didn't it?

mome rath · Post by **mome rath** » Wed May 28, 2014 8:21 am

Got mine, thanks

falafelbiels · Post by **falafelbiels** » Wed May 28, 2014 9:33 am

I loves it!

qp · Post by qp » Wed May 28, 2014 9:33 am

Oh yeah, mine with a hot pink panel came last week some time. Bought a white button. Considering painting it neon green.

falafelbiels · Post by **falafelbiels** » Wed May 28, 2014 9:35 am

You kids and yer bright colors...

Oh do post a picture when it's done eh?

falafelbiels · Post by **falafelbiels** » Sun Jun 08, 2014 3:13 am

Okay the kicks and hihats are not doing too well. For both the voiceboards are good, but the panelcomponentboards are not. The kick does work straight out of the box (after soldering up), but I am having a real hard time conjuring up infinite BOOOM out of it because of wrong placement of the resistor that should accomplish that. I f you are not looking for infinite BOOOM then it is just fine as is though.
The hihat however has a real problem. I have somehow inverted the trigger connections to the voiceboard which means the trigger inputs and go buttons are the other way around from what I would have preferred (no real problem, it works) and there is a trace that touches another (stupid, stupid, stupid). The latter is a real problem which can be fixed with a cut and a kludge, but that is not how things should be.

So yeah I am thinking about ordering a revision for both and hoping that my fix for infinite BOOOM will do the trick. I had this working on my very first ones with some kludging and don't get why I am having these problems now...

Everybody got their snare? I have received no complaints so I assume it's all good.

horstronic · Post by **horstronic** » Sun Jun 08, 2014 7:40 am

Yep, got mine.
Just didn't have the time to build it yet...

falafelbiels · Post by **falafelbiels** » Sun Jun 08, 2014 7:42 am

take your time, although I would love to see it in one of your slick panels!

horstronic · Post by **horstronic** » Sun Jun 08, 2014 8:40 am

falafelbiels wrote:take your time, although I would love to see it in one of your slick panels!

Here's a quick layout I did when I received the PCBs:

falafelbiels · Post by **falafelbiels** » Sun Jun 08, 2014 9:36 am

cool!

qp · Post by qp » Thu Jun 12, 2014 6:58 pm

finally got all of the parts! Well, most of em. The 100k pot is backordered, so I threw a 10k in there just to make sure all works and it does. I decided against the neon green.

falafelbiels · Post by **falafelbiels** » Fri Jun 13, 2014 7:02 pm

qp wrote:finally got all of the parts! Well, most of em. The 100k pot is backordered, so I threw a 10k in there just to make sure all works and it does. I decided against the neon green.

Love it

clean work also, mines don't look much like that (well to my eyes at least)

does it sound any good? that 10k could be alright, does it "crossfade" between between the low and high oscillator?

qp · Post by qp » Sat Jun 14, 2014 5:33 pm

falafelbiels wrote:
Love it

clean work also, mines don't look much like that (well to my eyes at least)

does it sound any good? that 10k could be alright, does it "crossfade" between between the low and high oscillator?

Thanks! Some of the parts were the wrong package (1u caps and the trimmer) so it doesn't look as clean as you think.

I've got some troubleshooting to do. The tone has no effect at all with the 10k. Also found the accent jack has no effect. Bummer is I don't have any time for the next couple of weeks to dig into it. I'm sure it's something stoopid.

Still may bust out the neon green paint...

falafelbiels · Post by **falafelbiels** » Sat Jun 14, 2014 8:50 pm

This here is the schematic for the panelcomponentboard, you may need it.

Some values are different on the PCB, like 8k2=10k...

Pd is for pulldown (100k) and bypass caps are left out in the schematic.

Acc in isn't really normalled to 12v, it used to be in an earlier version.

The pot is the little plastic shaft one. The other pots are in the main board schematic, which is the one by Eric Archer found here

MOD WIGGLER

MOD WIGGLER

808 snare PCBs