Earthquaker Devices - Talons

zedsnotdead · Post by **zedsnotdead** » 24 Feb 2015, 18:14

OFF-TOPIC

@darmstat
Could you tell me where do you host your images? Tks!

Edit: oh Forget about it, I think I found the answer ("Upload attachment" below....)

thesmokingman · Post by **thesmokingman** » 24 Feb 2015, 19:24

if you look closely, those LEDs are in a traditional feedback diode arrangement with 100p in parallel to them. traces on the other side back that up

Nocentelli · Post by **Nocentelli** » 24 Feb 2015, 19:39

thesmokingman wrote:if you look closely, those LEDs are in a traditional feedback diode arrangement with 100p in parallel to them. traces on the other side back that up

?
That's what the schematic shows.

zedsnotdead · Post by **zedsnotdead** » 24 Feb 2015, 19:40

Guys, need some help.

This is what I have so far. I named the componentes to make it easier to follow:

Now, I just haven't figured out where C12 is connected, although positive side of C10 gives me connected to 500k pot (drive) lug 3

Don't know if it's correct....

what do you think of this?

thesmokingman · Post by **thesmokingman** » 24 Feb 2015, 19:45

talons 7(the last one I saw on here) showed them in series

darmstat · Post by **darmstat** » 24 Feb 2015, 19:58

Looks better then what i came up with....lol

Nocentelli · Post by **Nocentelli** » 24 Feb 2015, 20:31

thesmokingman wrote:talons 7(the last one I saw on here) showed them in series

Yeah, my bad.

thesmokingman · Post by **thesmokingman** » 24 Feb 2015, 20:34

zed, the missing presence control will come off the first feedback loop just like the zendrive with a 1k in series with a 5k pot with a 3n3 to ground. low pass filter with corners from 8042.2 Hz to 48253.2 Hz

darmstat · Post by **darmstat** » 24 Feb 2015, 21:04

So...The presence is something like this ? ?

thesmokingman · Post by **thesmokingman** » 24 Feb 2015, 21:26

looks like lug 1 runs to the cap and 3 is tied to 2 and they run over to the resistor. and I dunno why I said the cap runs to ground ...

Nocentelli · Post by **Nocentelli** » 24 Feb 2015, 23:36

darmstat wrote:So...The presence is something like this ? ?

I really like the three band baxandall EQ on this, but i'm getting very little dirt with just a 3n3 cap on the presence control.

thesmokingman · Post by **thesmokingman** » 25 Feb 2015, 01:47

Yep ... Your comment fixed that for me ... So throw out the stuff about the presence control. The traces didn't follow like I thought when I blew up the pics plus it doesn't follow the logic. Whole purpose of that filter is to set the frequency of what doesn't clip. Hooray for failure!

zedsnotdead · Post by **zedsnotdead** » 25 Feb 2015, 02:15

Ok, I forgot the filter (presence) part.

here's how it looks like for what I could trace/verufy till now:

Im pretty sure C4 is grounded.

darmstat · Post by **darmstat** » 25 Feb 2015, 02:52

Hi Zedsnot dead. Cam e you confirm if the 10uf capacitor is at the vref ( resistor 93 and resistor 92)? I also think that at the end of the gain pot (500k) there maybe a 10k resistor and 1uf capacitor, then then the capacitor is connected to ground or vref?

thesmokingman · Post by **thesmokingman** » 25 Feb 2015, 03:39

Looks like 1u into 1k.

thesmokingman · Post by **thesmokingman** » 25 Feb 2015, 16:14

stared at it some more. zed's labeling has pin2 of op amp connected to c11 going to r12 to vref. corner frequency of high pass is 159.2Hz. presence is drawn correctly.
c12 goes from r93 to ground best I can tell.
also, you can just eliminate the question mark between pin3 of presence and c10.

zedsnotdead · Post by **zedsnotdead** » 25 Feb 2015, 19:50

Sorry guys, haven't had any time today.
I have to return the pedal tomorrow, so I'll try to check what's left as soon as possible. I think I will shoot again some new photos of the PCB, more detailed ones I hope ...

thesmokingman · Post by **thesmokingman** » 25 Feb 2015, 19:55

what else are you missing?

darmstat · Post by **darmstat** » 25 Feb 2015, 21:49

I think the 3 components i have circled. I am guessing that they go to the 500k pot for the gain?? Please look over.

zedsnotdead · Post by **zedsnotdead** » 25 Feb 2015, 22:06

hmmm.... I think that 500ka pot (gain) right lug (3?) is connected to a cap + resist that goes to the tone stack instead of Vref, much like the guvnor scheme.

Like this:

: marshallguvnor.gif (6.82 KiB) Viewed 2258 times

But let me check that when I get my hands on the pedal later tonight.

Earthquaker Devices - Talons [traced]