First Test of 18 Watt build - Sounds great but has a steady loud hum - Help

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JMPGuitars
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Re: First Test of 18 Watt build - Sounds great but has a steady loud hum - Help

Post by JMPGuitars »

Yamariv wrote: ↑
Sat 05/23/20 11:40 am
Keep me posted on your results when you swap the OT on the one amp in question..Curious to see your results! 8)
Swapping out the OT made a huge difference. The phaser sound / excessive crossover distortion is gone, and now I can finish tweaking the circuit, though I may leave it as it is.
Bieworm wrote: ↑
Sun 05/24/20 2:38 am
I don't like replacing OT's as a solution...rather spend that money for an new OT in a new amp 😁
Nobody does. I've never had a bad OT before, but this time I did. I'd rather have a great sounding amp than make excuses for a bad OT. ;)
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Re: First Test of 18 Watt build - Sounds great but has a steady loud hum - Help

Post by zaphod_phil »

I really hope you get a refund for the bad OT, Josh.
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Re: First Test of 18 Watt build - Sounds great but has a steady loud hum - Help

Post by JMPGuitars »

zaphod_phil wrote: ↑
Mon 05/25/20 3:57 pm
I really hope you get a refund for the bad OT, Josh.
No worries at all, they're sending a replacement.
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ampmadscientist
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Re: First Test of 18 Watt build - Sounds great but has a steady loud hum - Help

Post by ampmadscientist »

Is this a combo amp?
If so, ground the metal speaker frame to the amp chassis.
Then re-test to see if the hum is gone.
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Re: First Test of 18 Watt build - Sounds great but has a steady loud hum - Help

Post by zaphod_phil »

ampmadscientist wrote: ↑
Tue 05/26/20 12:06 pm
Is this a combo amp?
If so, ground the metal speaker frame to the amp chassis.
Then re-test to see if the hum is gone.
Sorry to say, but I'm pretty skeptical about that one. But it certainly won't hurt to try it :D
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Re: First Test of 18 Watt build - Sounds great but has a steady loud hum - Help

Post by Yamariv »

JMPGuitars wrote: ↑
Mon 05/25/20 7:11 am
Yamariv wrote: ↑
Sat 05/23/20 11:40 am
Keep me posted on your results when you swap the OT on the one amp in question..Curious to see your results! 8)
Swapping out the OT made a huge difference. The phaser sound / excessive crossover distortion is gone, and now I can finish tweaking the circuit, though I may leave it as it is.
Bieworm wrote: ↑
Sun 05/24/20 2:38 am
I don't like replacing OT's as a solution...rather spend that money for an new OT in a new amp 😁
Wow, amazing that you had the same issue as me and the OT fixed it totally, awesome news!! hurray hurray I'm totally blown away that a new OT could be faulty like that but I guess you never know!

I've been playing my TMB daily and it's finally every bit the amp I was hoping it would be when I first built it! It's also one of the quietest amps I own which is a crazy turn about..I've forgotten it on more than once cause it's so quiet! lol I've also had it cranked a few times (with earprotection on) and it is shockingly loud! Sounds friggen great at all volumes and would easily keep up in a decent sized venue!

Thanks for the update on your amp, very happy I fluked out with my issue and was able to help fix yours!
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Re: First Test of 18 Watt build - Sounds great but has a steady loud hum - Help

Post by crgfrench »

JMPGuitars wrote: ↑
Fri 05/22/20 12:53 pm
I think I'm gonna swap out the OT and see if it's cured.
What brand of OT was it?
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Re: First Test of 18 Watt build - Sounds great but has a steady loud hum - Help

Post by JMPGuitars »

crgfrench wrote: ↑
Mon 06/01/20 1:15 am
JMPGuitars wrote: ↑
Fri 05/22/20 12:53 pm
I think I'm gonna swap out the OT and see if it's cured.
What brand of OT was it?
GDS/Heyboer, and GDS took care of it. I've been through a lot of them, it was bound to happen eventually.
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