No sound since speedball install. [resolved]

Clmntbnr · 2195

0 Members and 2 Guests are viewing this topic.

Offline Clmntbnr

  • Jr. Member
  • **
    • Posts: 12
on: May 29, 2015, 01:40:06 PM
Hi !

I had no problem with the stock crack.
I installed the Speedball today and I just have no sound coming out...
I do have to say that I installed the heat sinks upside down, then I tried to remove them but it was really hard to do so I made sure to do the good wirings.
Beside that the voltages looked good, but some were pretty high (Those are 230V voltages), here they are:
2 & 4: 210
7 & 9: 130
15: 215
21 220
Note: I do hear a whispering of the high frequencies of the track when the volume is at it's maximum, both tubes a glowing normally.

Thanks for your help !

« Last Edit: June 19, 2015, 07:49:08 PM by Caucasian Blackplate »



Offline fullheadofnothing

  • Global Moderator
  • Hero Member
  • *****
    • Posts: 1487
  • A noble spirit embiggens the smallest man
Reply #1 on: May 29, 2015, 02:01:54 PM
Are you saying you built the board upside down?

Joshua Harris

I Write the Manuals That Make The Whole World Sing
Kit Packer Emeritus


Offline Clmntbnr

  • Jr. Member
  • **
    • Posts: 12
Reply #2 on: May 29, 2015, 10:10:33 PM
Only the heat sinks are on the wrong side of the board. It seemed really impossible to desolder them...



Offline Clmntbnr

  • Jr. Member
  • **
    • Posts: 12
Reply #3 on: May 29, 2015, 10:23:04 PM
Just received an email from Bottlehead saying some of us received faulty transitors marked "korea", witch mine are.
Maybe the problem is coming from this ?
Any advice in how to desolder the heat sinks ?



Offline Rocketman248

  • Full Member
  • ***
    • Posts: 156
Reply #4 on: May 29, 2015, 10:54:49 PM
If your heat sinks are on the opposite side of the board, and I presume the TIP-50 transistors are attached to those heat sinks, then the TIP-50 transistors will likely be backwards. 

To desolder those, you'll need some desoldering wick to try and get as much solder off as possible.  Getting the heat sinks off will be difficult, but not impossible.
« Last Edit: May 30, 2015, 03:34:00 AM by Rocketman248 »

Nick DeBrita
Yokosuka, Japan


Online Paul Birkeland

  • Global Moderator
  • Hero Member
  • *****
    • Posts: 19584
Reply #5 on: May 30, 2015, 08:52:52 AM
Can you post some photos of what you have built?

The defective Korean transistors are noisy, but otherwise functional. 

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Clmntbnr

  • Jr. Member
  • **
    • Posts: 12
Reply #6 on: June 01, 2015, 07:02:53 AM
Hi again !

Rocketman was right, so I reversed the TIP-50 transistors (I really tried to desolder the sinks and didn't manage to).
Now it's working, I've got sound + a big buzz on the left.
It is completely on the left at 0 volume and a little on the left when the volume is not down, and the gain of the buzz stays the same wherever the volume pot is.



Online Paul Birkeland

  • Global Moderator
  • Hero Member
  • *****
    • Posts: 19584
Reply #7 on: June 01, 2015, 09:30:53 AM
Now it's working, I've got sound + a big buzz on the left.
See the sticky about the Korean 2N2907 transistors.  If you don't have them, let us know here and we can continue debugging.

-PB

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Clmntbnr

  • Jr. Member
  • **
    • Posts: 12
Reply #8 on: June 04, 2015, 01:33:51 AM
Hi !

I do indeed have the faulty korean transistors, waiting for the new ones to arrive.
Meanwhile, I noticed something that may help, when I hold my jack while touching the chassis, the buzz almost stops completely (almost inaudible but still there)
Any recommendations ?
« Last Edit: June 04, 2015, 01:43:02 AM by Clmntbnr »



Online Paul Birkeland

  • Global Moderator
  • Hero Member
  • *****
    • Posts: 19584
Reply #9 on: June 04, 2015, 04:31:46 AM
when I hold my jack while touching the chassis, the buzz almost stops completely (almost inaudible but still there)
Any recommendations ?
Tighten all your #8 hardware, as you may not be making a super solid ground connection.  (Though the Korean transistors buzz on their own, so don't chase your tail until you get those replaced)

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Clmntbnr

  • Jr. Member
  • **
    • Posts: 12
Reply #10 on: June 19, 2015, 01:37:55 PM
The buzz was coming from the korean faulty transistors. Installed the new ones, my BC is working great. Thanks for the advices though !