Modded Crack - add bypass cap, choke and Cree diodes

ALL212 · 24031

0 Members and 1 Guest are viewing this topic.

Offline ALL212

  • Sr. Member
  • ****
    • Posts: 542
Reply #15 on: April 13, 2015, 01:39:09 PM
nice modding ALL! What do the cree diodes do for sound?

Can I just call it "Magic" and get away with it? ::)

Keep in mind that within 10 days I did the choke, bypass and Cree's so there wasn't a bunch of listening time with the cree's out of the mod.

With all three changes:
Bass is better, tighter, deeper.  Background is inky dark - you hear the room acoustics without effort.  Placement of individuals and instruments is precise. 

This "minor" mod goes a long way in proving the design of this headphone amp is spot on.  Very nice job Doc!

Aaron Luebke


Offline Jimb0

  • Sr. Member
  • ****
    • Posts: 289
Reply #16 on: April 13, 2015, 07:50:32 PM
Very interesting. I'm going to have to try it! Anything to make my Crack sound better!


James



Offline ALL212

  • Sr. Member
  • ****
    • Posts: 542
Reply #17 on: April 14, 2015, 05:36:20 AM
Please be careful of the Cree's - that silver tab is live and is a heatsink so you shouldn't cover them and they cannot touch anything - ever!

Aaron Luebke


Offline i luvmusic 2

  • Full Member
  • ***
    • Posts: 235
Reply #18 on: April 14, 2015, 11:36:34 AM
What tubes are you using?  And what headphones? 

Stalker alert!!   :o

Chatham 6AS7G and Tung-Sol 6SN7GTB(Tall Bottle),HD650 and DT 880 600R.



Offline ALL212

  • Sr. Member
  • ****
    • Posts: 542
Reply #19 on: April 16, 2015, 01:50:21 AM
You converted yours to use the 6SN7's?!  Nice!  Much better than 12AU7's?

I've got a RCA long black plate 5963, Tung-Sol5998 with HD650.  Source is a Squeezebox Duet with a Stello DA-220. 

Just bought another Crack kit.  Going to use it for testing and then, maybe, what I think I'll call a BAC (Big A$$ Crack).

Aaron Luebke


Offline borism

  • Full Member
  • ***
    • Posts: 158
Reply #20 on: April 21, 2015, 05:12:20 AM
This topic has encouraged me to add the Cree diodes to my already quite modified Crack (speedball, choke, output and last power supply film capacitors). I wasn't expecting as much improvement as it turned out to be. Still having difficulty putting my finger on it, but the Crees make it definitely sound better to my ears.

Boris


Offline daltonljj

  • Newbie
  • *
    • Posts: 4
Reply #21 on: May 19, 2015, 05:28:12 PM
i'm interested in modding my crack with the cree diodes But where do i get the board ??



Offline grausch

  • Full Member
  • ***
    • Posts: 126
Reply #22 on: May 19, 2015, 10:45:45 PM
You can get the pcb from PartsConnexion.

Here is a reference to the thread where this was first posted - http://bottlehead.com/smf/index.php?topic=7215.0. You can find a link to the pcb in there.

Gunter Rausch

Modded Bottlehead Crack
Modded Stereomour with Two-tone Orcas


Offline Jeb Jeb

  • Full Member
  • ***
    • Posts: 89
Reply #23 on: March 22, 2016, 09:50:09 AM


Parts Connexion have been out of stock since last year and I can't find a similar alternative.  Is there an alternative pcb that could be used  ?

Thank you!

James

« Last Edit: March 24, 2016, 04:43:09 AM by Jeb Jeb »

James Barker,
UK


Offline grausch

  • Full Member
  • ***
    • Posts: 126
Reply #24 on: March 22, 2016, 11:34:27 PM
Odd - I clicked on the link I provided in richmi's thread and it does not look out-of-stock to me.

Link ot the pcb - http://www.partsconnexion.com/product26996.html

Gunter Rausch

Modded Bottlehead Crack
Modded Stereomour with Two-tone Orcas


Offline Jeb Jeb

  • Full Member
  • ***
    • Posts: 89
Reply #25 on: March 23, 2016, 01:50:56 AM
Hi Gunter,

Yes Parts Connexion don't seem to have any real-time stock control, so I just place an order and then they email me and let me know if any items are out of stock.   They have been out of stock of these since late last year.  I've checked in with them every 5 weeks or so, but no luck.   They mentioned that everything is still way behind after Chinese new year.  I'm not in a hurry but thought I would check here just in case....

I think I'm sorted now -  this community is awesome.  :)


James Barker,
UK


Offline Chris65

  • Sr. Member
  • ****
    • Posts: 341
Reply #26 on: March 23, 2016, 02:23:19 AM
Yes Parts Connexion don't seem to have any real-time stock control, so I just place an order and then they email me and let me know if any items are out of stock.

That's right, they don't have real-time stock availability, you have to ask.



Offline larcenasb

  • Full Member
  • ***
    • Posts: 151
Reply #27 on: May 19, 2016, 05:52:03 AM
For anyone curious, I e-mailed Parts Connexion and they told me the PCB for this mod is back in stock!

Google "Discrete Bridge Rectifier PCB - TYPE 2 (TO-220 Radial Style)," and it's the second link.

I ordered mine and will post my impressions once installed. Happy listening and take care!

Lowell B.


Offline Colin

  • Jr. Member
  • **
    • Posts: 34
Reply #28 on: July 02, 2016, 12:45:26 PM
Is there a possibility use cree without the board? I've already changed the stocks with telefunken byt238, want to try these cree.



Offline ALL212

  • Sr. Member
  • ****
    • Posts: 542
Reply #29 on: July 11, 2016, 02:37:06 AM
One of our moderators posted that replacing any one of the existing diodes with just one Cree would do the job.  I've done it to one of my kits - maybe the Reduction?  You just have to be very careful of placement because of the tab.  Remember that they do have to go in the correct way.

Might be best to start a new thread so that you get attention to this before doing it?

Aaron Luebke