That amp is very hard on rectifier tubes!
Be sure to but one that has the glass the same diameter as the black plastic base.
Other ones not made as such are not real 5AR4 / GZ34 tubes, but glorified 5Y3GT tubes.
JMI AC30/6 NO SOUND
Moderators: pompeiisneaks, Colossal
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Stevem
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Re: JMI AC30/6 NO SOUND
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!
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pdf64
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Re: JMI AC30/6 NO SOUND
For goodness sake, no!Travis8 wrote: ↑Tue Aug 10, 2021 5:08 pm Could be better buy this one?
https://www.tubeampdoctor.com/en/tad-so ... -rectifier
That will put the output valves etc under far more stress.
The sales text seems extremely misleading to say the least, ie that the solid state module can just be straight swapped with the rectifier valves listed.
Last edited by pdf64 on Tue Aug 10, 2021 11:18 pm, edited 1 time in total.
https://www.justgiving.com/page/5-in-5-for-charlie This is my step son and his family. He is running 5 marathons in 5 days to support the research into STXBP1, the genetic condition my grandson Charlie has. Please consider supporting him!
Re: JMI AC30/6 NO SOUND
I had Sovtek 5AR4, if I use JJ GZ34/5AR4 It would fit?
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Stevem
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Re: JMI AC30/6 NO SOUND
Yes, and the JJ is of a better internal construction then then Sovtek.
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: JMI AC30/6 NO SOUND
mI can turn on and play a little but it blow fuses every 40 seconds.
Every time it blow one fuse a Blue Shine come from tubes
Every time it blow one fuse a Blue Shine come from tubes
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Stevem
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1 others liked this
Re: JMI AC30/6 NO SOUND
It sounds like one of the 4 output tubes are bad and since you do not have a tube tester or another amp to prove them out in all you can do is to order up a new quad of them.
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!
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johnnyreece
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Re: JMI AC30/6 NO SOUND
Just a tip: Depending on what you mean by "quickly", that can toast a rectifier tube. You want to give the rectifier time to cool before switching it back on, or it can flash over. 30 seconds or so should be plenty.
Re: JMI AC30/6 NO SOUND
HT fuses are great, but their rating needs to be chosen with a modicum of thought; T500mA in an AC30 is pretty pointless.
Mine runs fine on F250mA.
And why put it after the rectifier? As it is, it’s completely missing a likely, high potential failure mode, ie GZ34 anode to cathode short.
Does the fuse hold if all EL84 valves are removed?
Mine runs fine on F250mA.
And why put it after the rectifier? As it is, it’s completely missing a likely, high potential failure mode, ie GZ34 anode to cathode short.
Do you know that the new rectifier is good? eg have you got another amp you can try it in?
Does the fuse hold if all EL84 valves are removed?
https://www.justgiving.com/page/5-in-5-for-charlie This is my step son and his family. He is running 5 marathons in 5 days to support the research into STXBP1, the genetic condition my grandson Charlie has. Please consider supporting him!
Re: JMI AC30/6 NO SOUND
Today I changue the fuse and now it doesnt blow any fuse
Rectifier is working good and everything is working, but still getting no sound
I try new power tubes and the problem still there :/
This is frustrating
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Stevem
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Re: JMI AC30/6 NO SOUND
All your fuse blowing may have over loaded and now opened the power transformer.
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: JMI AC30/6 NO SOUND
You need to go back to checking idle VDC at relevant circuit nodes, eg EL84 cathodes, preamp valve anodes.
https://www.justgiving.com/page/5-in-5-for-charlie This is my step son and his family. He is running 5 marathons in 5 days to support the research into STXBP1, the genetic condition my grandson Charlie has. Please consider supporting him!
Re: JMI AC30/6 NO SOUND
The amp is working now.
The rectifier was bad, HT Fuse too and one resistor was open.
Thanks you guys
The rectifier was bad, HT Fuse too and one resistor was open.
Thanks you guys