Jubilee wild overtone issue? Speaker?

[xmacvicar]

Hey guys,

Just bought a well loved Jubilee 2554 1x12 from my local shop. Everything seemed great until I took it home. Now I am experiencing alot of crazy overtone/buzzing/farting which is very loud with certain bends and notes. Can anyone help diagnose this? I plan on taking it to the shop tomorrow where I purchased it, but anything input here will just help me further.

You can really hear it at 0:57 onward on this video. It is not buzz from the iPhone microphone; this is present when playing the amp as is. On another post someone thought it might be a torn speaker flapping at certain frequencies/notes?

[youtube][/youtube]

[surlybastard]

That is weird. Cone cry or perhaps a loose screw somewhere on the cabinet?

[Dave W]

Reminds me of the dreaded Class 5 combo buzz. The Class 5 buzz was caused by the chassis rattling.

Not trying tyo be a bummer, but people often trade amps with issues in to shops because they do not want to pay to fix them.

Sounds to me more physical than electrical.

Does the combo have a speaker out jack on it......plug it into your Avatar 2-12" that should rule out internal speaker or chassis buzz.

Other options are tightening all chassis and speaker screws

Press all around the cab, chassis and back of speaker cone to see if it eliminates the buzz.

Pull the chassis and leave it plugged into the speaker, then pull the speaker.

If its a physical thing, then it can be diagnosed with patience.

Could be a tube too that buzzes at certain frequencies or vibrations.

There are many options. all you can do is start ruling them out or take it back for a refund.

Best wishes and hope you find the source of the irritating buzz.

[Dave W]

This may sound stupid, but does it do it when you have the cab in the middle of the room?

You will be getting sound waves bouncing off that wall back into the cab as its close to the wall.

I have a wall on the inside of my closet that vibrates even when my Vintage Modern sits in my room. Took me days to figure out that as when cranked the buzz sounded like it was from the amp. Good Luck!

[xmacvicar]

Thanks Dave W...

I am starting to think maybe thats why this amp was brought in? It's certainly possible.

The avatar cab I have is 16ohm. This amp has options for 8 and 4 ohm only. I am still unsure if its safe to run the 16ohm avatar cab in the back?

I also was curious, how do you pull the chasis on these things? I am not understanding how you pull it out all the way (I was wondering this especially since changing the tubes was an option)

[JkGriffin]

This may sound stupid, but does it do it when you have the cab in the middle of the room?

You will be getting sound waves bouncing off that wall back into the cab as its close to the wall.

I have a wall on the inside of my closet that vibrates even when my Vintage Modern sits in my room. Took me days to figure out that as when cranked the buzz sounded like it was from the amp. Good Luck!

Weird enough, but this is true... the placement of the speaker may be a huge difference. When I had the Marshall JCM800 1987 I could dial in sweet Gilmour like tones on acceptable home levels not using an attenuator... then I placed it back against another wall and the amp totally "died". It sounded flat and transistor like. Same room, same furniture, same settings, same guitar, different placement.

The avatar cab I have is 16ohm. This amp has options for 8 and 4 ohm only. I am still unsure if its safe to run the 16ohm avatar cab in the back?

2x12? If so 2x12 in series? If you have 2x12 in series with 16ohm total, disconnect one speaker (make sure the ends don't short circuit) and use it as 8ohm. If you are unsure, measure the resistance. You'll not see 8ohm exactly but thereabout...

If in doubt, ask again

Oh, and yeah... as someone mention, doesn't have to be torn speaker as I suggested, but a loose screw may also cause the fizziness like that...

[xmacvicar]

Speaker was blown. a new v30 did the trick. I got the impression from the store manager that he thought I blew the speaker because I had the master volume up eight or nine. He told me to never put the master volume on 10 which makes sense... but historically isn't that what ppl do with marshalls? to crank them to get that creamy distortion?

I was playing it around 7-8 master volume. I didn't think that would damage anything?

[JkGriffin]

I don't buy it...

I guess you have a 50/25W switch... if so, what was it set on?
Crazy to crank a 50W at home at least...

So... if my internet sources are correct, your Silver Jubilee is 50W RMS and able to produce (in 50W mode) up to 90W output.
It was fitted (still is) with a Celestion V30 that is rated to 60W RMS and should be able to handle peak power twice that (120W).

If you were playing 25W that the sales guy is definitely bullshitting you... but if you used the 50W then I believe the sales guy may be bullshitting you....

[xmacvicar]

So nothing but bullshit from the sales guy?

Im confused...I have a Class 5 and I often have the volume at 10 to push the amp as far as it can go...should I NOT be doing that? Will I blow a speaker? The impression I got was to crank this guy and let the amp overdrive and just riff!

[MKB]

According to Steve D, one of the tests they perform on new Marshall designs is to crank the masters to 10 and feed simulated guitar signals into them, basically running them all the way up for an extended period of time. Marshalls are designed to be played full up. The store manager is either ill informed or pulling your leg a bit.

What speaker was in the amp, the one that you replaced? Was it the original speaker?

[xmacvicar]

it was the original celestion v30

[JkGriffin]

From what I can read you have two choices here...

1. You have a great amp... enjoy it. Just keep the lessons here in mind the next time...

2. Go back and ask for a discount as the speaker needed replacement. Tell him that a V30 can handle a 50W amp. You shouldn't expect a full V30 in discount as you are replacing an old speaker in an old amp with a brand new speaker... but...

Regardless... you have got yourself a great amp... the important thing is to keep that in mind and enjoy it.

[xmacvicar]

From what I can read you have two choices here...

1. You have a great amp... enjoy it. Just keep the lessons here in mind the next time...

2. Go back and ask for a discount as the speaker needed replacement. Tell him that a V30 can handle a 50W amp. You shouldn't expect a full V30 in discount as you are replacing an old speaker in an old amp with a brand new speaker... but...

Regardless... you have got yourself a great amp... the important thing is to keep that in mind and enjoy it.

Thanks JK....

Regarding point 1, what lessons am I to take from this? Sorry but I just misunderstanding....

They put the speaker in for free, all covered under warranty. The speaker replacement didn't cost me a thing. Do you think the new speaker warrants a discount on the overall amp because its not original? Or did you mean discount on the replacement speaker.

[Dave W]

I think it was not clear if you put the speaker in or the store.

Cool! Amp works!

Someone real picky could say that the amp is not stock if it has a new V30 in it from China as opposed to an older one from England. I think who cares....The store made good on their sale, thats great.

I will say this real clear though.....the guy at the store is a dumbass and does not know what he is talking about telling you to never play the amp at 10. Marshall would have put red warning paint on the volume dial from 7-10 if you played there at your own risk! Its a conservative rating of 60 watts on a V30. In have pushed speakers over their listed limit before. Your speaker just went bad, it happens, it was not necessarily abused. Your speaker was bad before you took the amp home in all likeleyhood. its possible no one was aware of it, maybe not even the guy who traded it in. It don't matter now.

If its a brand new speaker it will sound even better once broken in. If its already broken in then thats fine too.

Glad to hear the store treated you right and that your amp is up and running without the BUZZ! Enjoy!

[xmacvicar]

You guys here on the Roadhouse are amazing. You really helped me through the purchase and finding the defect in the speaker. I have so many more replies from you guys here than the "marshallforum" - not a single reply there.

Moving forward, I am super pumped to be a part of the bigger marshall family and look forward to your advise and knowledge for the years to come!