Welcome to Solid State Guitar Amp Forum | DIY Guitar Amplifiers. Please login or sign up.

July 25, 2024, 02:28:01 PM

Login with username, password and session length

Recent Posts

 

Recent posts

#1
The Newcomer's Forum / Re: NEWB needs help with an El...
Last post by J M Fahey - Today at 01:51:11 PM
Is it the Electro Harmonix Freedom amp?
There are a couple gut pictures floating around.

Never heard of Freedom "Brothers" though.

Post a picture or two for identification.
#2
Tubes and Hybrids / Re: Tube Amp Trouble
Last post by The Dude - July 24, 2024, 10:25:03 PM
FWIW: Unless board mounted and covered up, there is usually an accessible hole in the center of a 9 pin socket. You can use a chop stick or something of the sort to help push the tube out of the socket from the bottom side.
#3
Amplifier Discussion / Re: Reverb Sidekick 35 Buzz
Last post by The Dude - July 24, 2024, 06:57:15 PM
That's not corrosion. It's flux. Not a problem. If you turn the master all the way down (as Juan suggested) is the noise still present? Also, grab the top of those caps and give them a SLIGHT wiggle. That might tell you if any are loose.
#4
Amplifier Discussion / Re: Reverb Sidekick 35 Buzz
Last post by jasper2021 - July 24, 2024, 06:56:44 PM

Good.
To my ears it's too buzzy raspy rather than deep hummy, I suspect you lost some ground between amp input and preamp

What happens if you set Master to 0?

What if you short power amp input terminals together?

Trying to find *where* buzz gets in.
[/quote]

I turned on the board with the speaker disconnected, and I could hear a similar buzz (quieter, obviously) that seemed tk be coming from the transformer... does that help?

Turning the pots didn't affect the speaker buzz at all...

By short the power amp input terminals you mean connect them? And see if it buzzes or am I checking voltage at the speaker leads again? Forgive my inexperience - I know basic circuitry and can do house wiring and car stereos, but that's about as much troubleshooting as I've done.
#5
Amplifier Discussion / Re: Reverb Sidekick 35 Buzz
Last post by jasper2021 - July 24, 2024, 06:42:52 PM
Quote from: The Dude on July 23, 2024, 10:29:36 PMThat sounds like poor power supply filtering to me. I'd check caps C30, C31, C26, & C27. First, make sure they are properly soldered to the circuit board. It's quite possible you just have a cracked solder joint on one of the caps.

Ok, so it looks like some corrosion (?) on the solder, and some of the connections aren't pretty. I think there might also be problem spots on the bass pot and what I think are fuses(?) Have a look at these pictures and tell me what you think: https://flic.kr/s/aHBqjBBdor
#6
Amplifier Discussion / Re: Reverb Sidekick 35 Buzz
Last post by J M Fahey - July 24, 2024, 06:21:19 PM
Quote from: jasper2021 on July 24, 2024, 05:17:23 PM
Quote from: DrGonz78 on July 23, 2024, 08:13:57 PMRemove the speaker from the amp. If there is DC voltage leaking into your speaker it may damage it. Next use a multimeter set to read dc voltage across the speaker leads. What does it read?

Multimeter reads 0.15V across the speaker while it's buzzing..
Good.
To my ears it's too buzzy raspy rather than deep hummy, I suspect you lost some ground between amp input and preamp

What happens if you set Master to 0?

What if you short power amp input terminals together?

Trying to find *where* buzz gets in.
#7
Amplifier Discussion / Re: Reverb Sidekick 35 Buzz
Last post by jasper2021 - July 24, 2024, 05:17:23 PM
Quote from: DrGonz78 on July 23, 2024, 08:13:57 PMRemove the speaker from the amp. If there is DC voltage leaking into your speaker it may damage it. Next use a multimeter set to read dc voltage across the speaker leads. What does it read?

Multimeter reads 0.15V across the speaker while it's buzzing..
#8
Amplifier Discussion / Re: Reverb Sidekick 35 Buzz
Last post by The Dude - July 23, 2024, 10:29:36 PM
That sounds like poor power supply filtering to me. I'd check caps C30, C31, C26, & C27. First, make sure they are properly soldered to the circuit board. It's quite possible you just have a cracked solder joint on one of the caps.
#9
Amplifier Discussion / Re: Reverb Sidekick 35 Buzz
Last post by DrGonz78 - July 23, 2024, 08:13:57 PM
Remove the speaker from the amp. If there is DC voltage leaking into your speaker it may damage it. Next use a multimeter set to read dc voltage across the speaker leads. What does it read? We don't want to accidentally short them together and definitely remove the speaker. If it is not DC voltage on the output it may be something right in the preamp. But first test the power amp side to be careful.
#10
Amplifier Discussion / Reverb Sidekick 35 Buzz
Last post by jasper2021 - July 23, 2024, 06:58:54 PM
My Sidekick Reverb started giving me issues out of the blue. Lots of humming with nothing plugged in. Here's a video of the issue.  I found a wiring schematic and I opened it up to see if there was any obvious signs of damage but it all looks OK to my beginner's eyes.

Can anyone help me diagnose this issue?  If anyone can point me in the direction of some good troubleshooting resources, I have yet to find anything on my own.