Modded Crack - add bypass cap, choke and Cree diodes

[oguinn]

I tried looking at the original thread where this mod was discussed, but it seems like it's either archived or moved. Does anyone have the full instructions? Link to the original: https://bottlehead.com/smf/index.php?topic=7215.0

[oguinn]

Actually I found this reply in another thread:

Below are some links I have saved for these mods that I intend to do at some point.

For broken links and particularly for images I quite often just do a google image search for something relevant in the threads

Bridge Rectifier
You don't really need the PCB as the circuit is as you would expect and you can replicate on prototyping board or similar.

NB There are reminders that the tabs on the top of the diodes are live and should not touch anything ever.

• PCB - https://www.partsconnexion.com/PCB-77727.html
  
• Cree Diodes https://www.mouser.co.uk/ProductDetail/Wolfspeed-Cree/CSD01060A?qs=%2Fha2pyFaduha8e7L7P6H8AQPAaWzRYR18hPNYjU5%252Bzc%3D.
  
• Wiring guide - https://cdn.head-fi.org/g/9937481_l.jpg
  

Choke

• https://www.mouser.co.uk/ProductDetail/Triad-Magnetics/C-7X?qs=sGAEpiMZZMuMS2dUaCDnDB57UyZo4e84

This replaces one of the two big white 270 Ohm 5W resistors. Most people seem to replace the one between 13L and 15L

Does the "Old Transformer" and "New Transformer" refer to versions of the Crack transformer? I assume so, like a Crack 1.0 or 1.1?

[Paul Birkeland]

Yes, the 1.0 and the 1.1 have different power transformers.

[oguinn]

Got it, thanks. Filing this away under "future upgrades if they can get the PCB back in stock."

[Deke609]

Maybe you could just make one with protoboard using wire in place of the traces as Ianp suggests in the quote?

Or maybe the axial style recitifier board (in stock at Parts Connexion) could be made to work by bending the leads of the diodes?  https://www.partsconnexion.com/PCB-77726.html

[oguinn]

Maybe you could just make one with protoboard using wire in place of the traces as Ianp suggests in the quote?

Or maybe the axial style recitifier board (in stock at Parts Connexion) could be made to work by bending the leads of the diodes?  https://www.partsconnexion.com/PCB-77726.html

The extent of my electrical abilities extends to poorly soldering and following extremely explicit directions written by people way smarter than me; I'm not sure I want to take on protoboards since there's a 95% chance I'll solder my dog to the amp by accident.

I've got some feelers out for the actual PCB, but I might give the other version a shot. Or maybe get the pre-built one and yank out the existing diodes.

[ALL212]

The extent of my electrical abilities extends to poorly soldering and following extremely explicit directions written by people way smarter than me; I'm not sure I want to take on protoboards since there's a 95% chance I'll solder my dog to the amp by accident.

I've got some feelers out for the actual PCB, but I might give the other version a shot. Or maybe get the pre-built one and yank out the existing diodes.

Solder your dog to the amp....

From a comedy standpoint the fun to be had with that comment is almost limitless.
From an animal cruelty standpoint I'm not going there for any reason.

but that's just funny stuff right there...

[oguinn]

I really like my dog and would like to keep her separate from the amp for obvious reasons. That's why I'm leaving protoboards to people with a higher IQ than mine (44).

[Deke609]

Was perusing the Parts Connexion site and just noticed that the radial style rectifier board is back in stock. Grab'em while you can!

[carlman14]

Maybe you could just make one with protoboard using wire in place of the traces as Ianp suggests in the quote?

Or maybe the axial style recitifier board (in stock at Parts Connexion) could be made to work by bending the leads of the diodes?  https://www.partsconnexion.com/PCB-77726.html

Reviving this suggestion to see if anyone knows. The "Discrete Bridge Rectifier PCB - TYPE 2 (TO-220 Radial Style)" seems to be perpetually out of stock. Does anyone know if that axial version of the rectifier board would work for the cree mod? I can't find any posts of anyone actually using the axial board...

[ALL212]

   I have a few of those...just not sure where I put them.  If I find them I'll see if the traces look similar to the other board.  I've never used those...yet.

[oguinn]

Reviving this suggestion to see if anyone knows. The "Discrete Bridge Rectifier PCB - TYPE 2 (TO-220 Radial Style)" seems to be perpetually out of stock. Does anyone know if that axial version of the rectifier board would work for the cree mod? I can't find any posts of anyone actually using the axial board...

They got back to me a couple days after I requested they notify me when they’re in stock. I think they’re just ordering them when people ask.

[carlman14]

Oh ok! I'll contact them and see what happens! I'd definitely prefer to use the board that everyone else is using...

[tim273]

There's some new Schottky Diodes available on Mouser, would one of these work instead?  If so, better or worse then the previous version?

https://www.mouser.com/new/wolfspeed/wolfspeed-c6d-diodes/

[Paul Birkeland]

There's some new Schottky Diodes available on Mouser, would one of these work instead?  If so, better or worse then the previous version?

They are ultimately pretty similar to the 600V/1A parts.  The minor differences are not worth the dramatically increased price IMO.