Squealing 8W SE
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Stevem
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Re: Squealing 8W SE
I think the op should start a new thread to get the topic back onto what his issue is!
When I die, I want to go like my Grandfather did, peacefully in his sleep.
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Re: Squealing 8W SE
Maybe the mods will split the thread to restore this one to the OP. Call the other one "8W from a 5W tube." I'd like to see where it goes, though I don't think we'll be surprised in the end.
Re: Squealing 8W SE
Does this qualify as shielded cable?:Stevem wrote: ↑Fri Sep 17, 2021 10:12 am The first thing I would do would be to use shielded wire to go from the input jack to the board.
The shield should be grounded / connected only at the input jack.
On the other end it should be Heat shrinked off.
In the tight confines of the lunch box type Orange amps that I have kicked the gain up on for people I have had to make a card board and Aluminum foil shield to place around the whole input jack to get the amp to stop back talking at high volumes!
When a input jack / antenna and a speaker jack are within 5 inches of each other in a high gain amp, these are the things that can happen!
Re: Squealing 8W SE
Lol... I don't really mind that it's 5W, it's plenty loud in my homestudio, I can't remember going past 2 o'clock on master volume.
The squealing is what bothers me.
Thanks!
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pompeiisneaks
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Re: Squealing 8W SE
That definitely looks like it. I can't see what the inside wire looks like, or how heavy the outside shielding is, but you usually connect the shield to the circuit - so as to route signals out of the signal path that are 'noise' being injected into the non shielded wires. I.e. ground the noise so it can't go into the signal path.
Normally only done on one side as well to avoid creating ground loops.
~Phil
Normally only done on one side as well to avoid creating ground loops.
~Phil
tUber Nerd!
Re: Squealing 8W SE
Techniforte Mojopath? Low capacitance instrument cable? I guess that will work but not ideal because it has a large diameter. RG59U or RG58 are more typical for this purpose.
Re: Squealing 8W SE
Are you sure? I usually connect the center conductor to the circuit and ground one end of the shield. The ground can be at any convenient spot on the chassis.
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Stevem
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Re: Squealing 8W SE
The accepted rule of thumb for audio and especially XLR balanced cables is “ tie out and lift in”
So the shield would not get landed anywhere near a tube socket, but in the OPs case it would land at the input jack.
So the shield would not get landed anywhere near a tube socket, but in the OPs case it would land at the input jack.
When I die, I want to go like my Grandfather did, peacefully in his sleep.
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
-
pompeiisneaks
- Site Admin
- Posts: 4244
- Joined: Sat Jan 14, 2017 4:36 pm
- Location: Washington State, USA
- Contact:
Re: Squealing 8W SE
I probably should have said
"you usually connect the shield to the circuit negative " not "...circuit -" as "-" can be mistaken for a hyphen... ;D
~Phil
tUber Nerd!
Re: Squealing 8W SE
yes, it was thick lol...
but I managed to install it, now the input cable is shielded.
Still squealing, though!
but I managed to install it, now the input cable is shielded.
Still squealing, though!
Re: Squealing 8W SE
it is a ** construction, send pls those video to the constructor we will wait for the reply
also transformers are mounted in the worst position .. you can try to reduce gain with other tube and that's it, not possible to do too much if you have 0 experience ..
(i would cut gain at least 100% and those pots look like problematic too, have "step" contact, lifting tube grid from the ground-dangerous operation one 500k added resistor over the pot would hep)
also transformers are mounted in the worst position .. you can try to reduce gain with other tube and that's it, not possible to do too much if you have 0 experience ..
(i would cut gain at least 100% and those pots look like problematic too, have "step" contact, lifting tube grid from the ground-dangerous operation one 500k added resistor over the pot would hep)
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Stevem
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- Joined: Fri Jan 24, 2014 3:01 pm
- Location: 1/3rd the way out one of the arms of the Milkyway.
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Re: Squealing 8W SE
The next step I would do if you felt confident enough to disassemble the amp would be to twist together the 3 wires on the input side of the output transformer, and then do the same with the 4 wires on its output side while also cutting them back as short as possible.
As you disassemble take pictures for reference!
As you disassemble take pictures for reference!
When I die, I want to go like my Grandfather did, peacefully in his sleep.
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Re: Squealing 8W SE
I've spoken to him when I bought the amp second-hand... he said "they squeal near max gain, unfortunately" lol... I guess he's not that interested anymore.bepone wrote: ↑Sat Sep 18, 2021 9:22 am it is a ** construction, send pls those video to the constructor we will wait for the reply
also transformers are mounted in the worst position .. you can try to reduce gain with other tube and that's it, not possible to do too much if you have 0 experience ..
(i would cut gain at least 100% and those pots look like problematic too, have "step" contact, lifting tube grid from the ground-dangerous operation one 500k added resistor over the pot would hep)
I'll change the tube, and the 500K resistor over the pot I can do easily, which pot?
Lifting tube grid, I'll pass on that
Twisting transformer wires... I guess I can do that but later, when I'm feeling brave enough.
I have a feeling that getting a 12AT7 will do the trick!
disclaimer: I don't regret buying it, it sounds great and I really don't need all that gain or max volume.