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Post by larryguitar54 on Jan 7, 2022 16:26:34 GMT -5
My TRRI intermittently will produce static. I turn all the knobs to -0- including the volume, vibrato and EQs. I tap all the tubes with no sound. It has no effect on the static. Is this common?
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Post by Peegoo 🏁 on Jan 8, 2022 4:55:29 GMT -5
Not exactly common, but it happens. One or more power tubes going bad can create this symptom. Power down the amp. There are four power tubes on the left, looking at the back of the amp. Pull the two outside power tubes and switch the amp on. See of the crackle is still there. If yes, power down the amp, replace the outer tubes, and pull the two inside tubes. Power the amp back on. Any change?  |
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DrKev
Wholenote
It's just a guitar, it's not rocket science.
Posts: 418
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Post by DrKev on Jan 27, 2022 8:26:23 GMT -5
What he said! That's precisely what you should do.
If you need to go further after that, pull the preamp tubes, one by one. If it's not any of the tubes, it's time to see a tech.
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Post by Peegoo 🏁 on Jan 28, 2022 12:56:45 GMT -5
What's the verdict, your honor?
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Post by larryguitar54 on Jan 29, 2022 16:06:07 GMT -5
In the meantime it 'just went away'. But that has been the case before. I do intend to put in on the table and take out the tubes.
But I remind my brothers we are talking about Fender Twin Reverb. In other words it's heavier than Thor's Hammer.
I think I will wait until actual flames or blue lightning develops before I try to lift it.
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Post by larryguitar54 on Jan 30, 2022 19:07:31 GMT -5
PS...Spent some time as an amateur amp tech. I have a TRRI BF'08 with Jenson 12s. The findings:
a.) Took back off and powered up and tapped carefully with with chopstick listening for something untoward.
b.) Tube in V4 was slightly microphonic when lightly tapped top of tube.
c.) Volume pot in Reverb channel was scratchy.
d.) When turned volume in each channel to 5 the Reverb channel was a bit more noisy than Normal channel--even with reverb off.
e.) Decided problem is in the reverb channel and start with replacing the tubes. I did replace the V4 with a 12AX7 that I knew was noisy and sure enough it was noisy and was worse than the microphonic tube. I can avoid it by staying in the normal channel.
Doing the research I noticed the reverb tubes in V3 and V4 are different than V1 to V6.
One of the things that has always bothered me about the TRRI is that the Reverb and Tremelo is way too sensitive. At 2.5 it's already too much and anything more than 3 is unusable for me. I also noticed V4 is a preamp tube for Tremelo. So that explains why the reverb and tremelo seem to have the same related issue.
I am thinking I might like a lower powered tube in V3 and V4 so I can get better control with a broad sweep. Also as I might want to go with higher quality I am looking for consensus on what is the best tube set for a TRRI. I see the usual suspects JJ, Mullards, GT etc.
Thoughts?
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Post by Peegoo 🏁 on Jan 30, 2022 22:46:20 GMT -5
Call me crazy but I like the sound of Sovtek 12A-7s. They do sound fantastic.
I'm no Mullard snob...because modern Mullards are rebranded offshores anyway. And the cost of actual NOS tubes is stupid. The law of diminishing returns is strictly enforced when it comes to NOS tubes. You really do not get what you pay for.
Vendors of NOS tubes will swear I'm an idiot--but remember they make a living selling NOS tubes.
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Post by roly on Feb 5, 2022 1:00:48 GMT -5
I suggest that you get the amp working properly with correct tubes before you start switching things out.
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Post by larryguitar54 on Feb 5, 2022 16:15:45 GMT -5
Yup that makes sense.
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Post by bluzcat on Feb 13, 2022 15:18:00 GMT -5
I had some static on mine that progressed to eventual static/intermittent volume. Turned out to be a cold solder joint on the bias cap. Since I had to flip the board over anyway I just decided to replace all the electrolytics.
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