OKKO Dominator

mundry · Post by **mundry** » 21 Feb 2011, 20:33

Thank to both of you for the info, it seems that I was too excited about this project and had too much hurry to pass it to the forum, I understand that the best solution at last is to keep IC2 supply on Vb and using a TL074.

sansaat · Post by **sansaat** » 28 Feb 2011, 16:41

Hi everybody,
First time poster long time lurker. Just build the Dominator using the vero layout made by hbo and it works very well. I used the 5819 schottkys for the voltage doubler and one of the FETs was BF245C because I only had one BF245A. The voltage doubler produced 16,4V and the 78L15 made it into a 14,8V.

roseblood11 · Post by **roseblood11** » 28 Feb 2011, 18:47

Great!
What about the changed parts values that where posted after that vero layout?

Has someone used the pcb layout?

If someone in germany or nearby etches a board, please contact me, I could need one, too!

sansaat · Post by **sansaat** » 28 Feb 2011, 19:20

hbo updated the vero layout after the changes were made. I forgot to thank Saruman and hbo in my first post so big thanks to you guys!

Post by **audioguy** » 01 Mar 2011, 12:25

Any functional PCB yet?

roseblood11 · Post by **roseblood11** » 01 Mar 2011, 18:46

audioguy wrote:Any functional PCB yet?

what about reading the thread?

sansaat · Post by **sansaat** » 01 Mar 2011, 23:16

Here's a couple of pictures of my dominator. It's really weird that i got only 16,4 volts with the voltage doubler in the okko and 17,7 volts with the voltage doublers in my a/da flanger and in my SFT. Even with 16,4 volts the dominator sounds really good.

ben_allison · Post by **ben_allison** » 26 Mar 2011, 15:51

Just read the thread; awesome work.

I'm still not entirely clear, though, if the schem, layout, and bom are 100% verified?

Post by **audioguy** » 04 Apr 2011, 17:24

mundry wrote:here's the latest version 1.2

-i've changed the IC2 supply from Vb to Va so the supply of IC1 and IC2 is the same, i don't understand what kind of problem can introduce R38

guiddruid wrote:Probably better going the other end of R38 - I assume that resistor is there to affect the distortion stage.
-updated the charge pump diodes with schotty type (i'll try it Roseblood)

who had already made pcb with previous old versions can easily replace the TLC2274 with the TL074 without change anything

Has this PCB been verified yet?

gefi · Post by **gefi** » 05 Apr 2011, 17:38

mundry wrote:here's the latest version 1.2

-i've changed the IC2 supply from Vb to Va so the supply of IC1 and IC2 is the same, i don't understand what kind of problem can introduce R38

guiddruid wrote:Probably better going the other end of R38 - I assume that resistor is there to affect the distortion stage.
-updated the charge pump diodes with schotty type (i'll try it Roseblood)

who had already made pcb with previous old versions can easily replace the TLC2274 with the TL074 without change anything

Hello

This PCB is checked?, it is functional?
Greetings

sansaat · Post by **sansaat** » 05 Apr 2011, 20:58

I accidently used 5,6n for the c22 instead the 1n that was in the vero layout. So i put the correct 1n cap in and the pedal got even meaner. It's also suprisingly quiet even with the gain pot maxed. And apparently i don't know how to upload pictures

irombrus85 · Post by **irombrus85** » 19 May 2011, 20:23

Hi guys,i write from Italy

sorry for my english
Mundry's layout it's VERIFIED because I did and the Dominator is a bomb! coooool
Thanks to all for their work, some pictures of the toy:

roseblood11 · Post by **roseblood11** » 19 May 2011, 20:41

Nice built!

This is my pedal, I used hbo's vero layout:

Ihunda · Post by **Ihunda** » 02 Jun 2011, 12:02

Many thanks for the schematics and layouts!

I was studying the circuits last night and it looks like the dominator doesn't really need those Jfets.
It's applying eq before and after distortion, with the typical rule: remove bass before distortion, add it back afterwards.
But the distortion is coming form opamp overload only...
To those you have built one: have you tried or could you try going direct to the opamp? It seems to me that the circuit can be simplified and still be TEH BROOTAWL BOX.
-- G

roseblood11 · Post by **roseblood11** » 02 Jun 2011, 12:56

I lost interest in this pedal since I´ve listened to Wamplers "Triple Wreck"...

rcustoms · Post by **rcustoms** » 02 Jun 2011, 14:18

i agree with you and also saw and heard on youtube the comparison with mi tube zone awesone

Ihunda · Post by **Ihunda** » 03 Jun 2011, 19:46

Any schematics for the Wamplers "Triple Wreck" or the mi audio?

Ihunda · Post by **Ihunda** » 03 Jun 2011, 19:49

Sorry to answer myself

Triple wreck: https://www.freestompboxes.org/viewtopic.php?f=7&t=10737
Mi Audio tube: https://www.freestompboxes.org/viewtopic ... ve#p110656

Ihunda · Post by **Ihunda** » 03 Jun 2011, 20:03

That's what I though, no jfet in there, distortion is coming from opamps and diode, that's all u need

DimebuGG · Post by **DimebuGG** » 03 Jun 2011, 23:20

roseblood11 wrote:I lost interest in this pedal since I´ve listened to Wamplers "Triple Wreck"...

You should try at least both in a live band situation and compare whose the real killer.

OKKO Dominator [traced]