Amp is really quiet--did I screw up my power tube? [resolved]

ohshitgorillas · 1514

0 Members and 1 Guest are viewing this topic.

Offline ohshitgorillas

  • Full Member
  • ***
    • Posts: 61
To start, my stock Crack worked perfectly well.

While installing Speedball, my power tube fell onto the floor off of my coffee table, ~1.5 ft. Now, I've double and triple checked my Speedball wiring. I've made extra sure that none of the solder joints for the smaller transistors are overlapping, that everything is clean and in the right place. I'm about 85% sure that the Speedball is properly assembled, but open to suggestions if someone's had a similar issue.

But the sound coming out of the amp is really quiet--full volume on the amp is a low to moderate listening level in the right channel, and the left channel is present but significantly quieter still. The bass is a little warbley at times too.

Does this sound like a tube that took too hard of a fall, or do y'all think that the issue is in the Speedball? Any suggestions?
« Last Edit: April 23, 2015, 05:49:34 PM by Caucasian Blackplate »



Offline fullheadofnothing

  • Global Moderator
  • Hero Member
  • *****
    • Posts: 1487
  • A noble spirit embiggens the smallest man
Reply #1 on: April 22, 2015, 10:38:22 AM
Voltages...?

Joshua Harris

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


Offline ohshitgorillas

  • Full Member
  • ***
    • Posts: 61
Reply #2 on: April 22, 2015, 01:23:21 PM
Everything checked out. Here are the measurements in V:

1. 72
2. 183
3. 0
4. 183
5. 181
6. 0
7. 109
8. 0
9. 179
10. 0
11. 0
12. 0
13. 183
14. 0
15. 201
20. 0
21. 218



Offline fullheadofnothing

  • Global Moderator
  • Hero Member
  • *****
    • Posts: 1487
  • A noble spirit embiggens the smallest man
Reply #3 on: April 22, 2015, 01:30:31 PM
Your voltages are off at 5 and 9. One of your small boards has a 31.6Ω resistor where there should be a 237Ω resistor. Find the 237Ω on the big board, where it shouldn't be.
« Last Edit: April 22, 2015, 01:33:30 PM by fullheadofnothing »

Joshua Harris

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


Offline ohshitgorillas

  • Full Member
  • ***
    • Posts: 61
Reply #4 on: April 22, 2015, 03:08:29 PM
You were right! Thanks so much!