JCM 900 with Bugera PS1 Attenuator Smoked!

[Ryan Kirk]

I purchased a Bugera PS-1 100W attenuator and followed the instructions with proper functioning speaker cables and matched impedance @8ohms.

Sounded great for about 5 minutes, I let the 50W JCM900 4500 series warmup for about 20 minutes then started dialing in an awesome tone and I started smelling burning parts. I stopped playing and noticed the PS-1 was smoking just a little bit. Little smoke signals is the best way to describe it. I turned it off immediately. Is this a product error or are the JCM 900’s just not cut out for attenuators? Your thoughts please and thank you guys. I’m new by the way. Been playing since I was 13 and I’m 30 now.

Side note* Used a 4x12 Marshall cab 8ohms

 

[houseofrock]

Is the amp ok?
If so my guess would be the attenuator. I would try the Weber Mass 200. https://www.tedweber.com/mass-200
others will chime in with a different opinion.
Check your speaker cabinet wiring.

 

[Micky]

What model cab?

 

[charveldan]

Hate to say i told you so but not surprised in the least.
Boogera stuff is bottom of the barrel.
Mass produced garbage.

 

[JohnH]

A 100W-rated attenuator should be able to deal with a 50W amp (though arguably not a 100W amp). I call faulty PS1!

Ps. .is PS1 a shortened form of PoS1?

 

[Ryan Kirk]

What model cab?

MG412A it’s for my bedroom really.

 

[Ryan Kirk]

Another guitarist sent me this and I’m assuming it could be what’s going on but from what I’m hearing on Facebook and in here, I need to just dump it and get my money back.

 

[ibmorjamn]

Doesn't the JCM 900 have a issue that burns the board ? I forget what it was but there are threads about it. Check the PC board visually. Not the re-issue ones.

 

[charveldan]

Only attenuator that i knew had a speaker motor was the Weber Mass unless some of the newer ones do.
The PS-1 is a Jettenuator knock off.
Its purely a resistive load.
Have you ever measured the impedance of your cab with a meter ?
Does your cab have 1 or 2 speaker jacks ?

 

[ampmadscientist]

I purchased a Bugera PS-1 100W attenuator and followed the instructions with proper functioning speaker cables and matched impedance @8ohms.

Sounded great for about 5 minutes, I let the 50W JCM900 4500 series warmup for about 20 minutes then started dialing in an awesome tone and I started smelling burning parts. I stopped playing and noticed the PS-1 was smoking just a little bit. Little smoke signals is the best way to describe it. I turned it off immediately. Is this a product error or are the JCM 900’s just not cut out for attenuators? Your thoughts please and thank you guys. I’m new by the way. Been playing since I was 13 and I’m 30 now.

Side note* Used a 4x12 Marshall cab 8ohms

I think I warned about using attenuators made in China...
(maybe will listen now?)
Well, lucky if it didn't melt the output transformer...hope you learned a lesson.

The lesson was: use only professional attenuators.

 

[ampmadscientist]

Doesn't the JCM 900 have a issue that burns the board ? I forget what it was but there are threads about it. Check the PC board visually. Not the re-issue ones.

The amp (for some reason) can burn a hole through the output (rear) board, I am guessing impedance mismatching ?

 

[Mitchell Pearrow]

I purchased a Bugera PS-1 100W attenuator and followed the instructions with proper functioning speaker cables and matched impedance @8ohms.

Sounded great for about 5 minutes, I let the 50W JCM900 4500 series warmup for about 20 minutes then started dialing in an awesome tone and I started smelling burning parts. I stopped playing and noticed the PS-1 was smoking just a little bit. Little smoke signals is the best way to describe it. I turned it off immediately. Is this a product error or are the JCM 900’s just not cut out for attenuators? Your thoughts please and thank you guys. I’m new by the way. Been playing since I was 13 and I’m 30 now.

Side note* Used a 4x12 Marshall cab 8ohms

Welcome to the forum.
I have never played with an attenuator so I am not much help.
I do hope your amp is ok.
Cheers Mitch

 

[Ufoscorpion]

I’ve been using a jettenuator for a couple of years now on many amps including a 2203x master on 7 and absolutely no problems whatsoever . A faulty attenuator I would say.

 

[67Mopar]

I hate it when the OT melts through the chassis... Dammit!

 

[ibmorjamn]

Another guitarist sent me this and I’m assuming it could be what’s going on but from what I’m hearing on Facebook and in here, I need to just dump it and get my money back.

So is the amp dead or alive ?

 

[ampmadscientist]

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[Mitchell Pearrow]

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[bad565ss]

I have one of these. It works good with my 1987 but for some reason it gets hot with the 2204. I would not use it with a 100 watter myself.

 

[charveldan]

You get what you pay for. For a little more than the price of Boogera crap you can have something nice that will last & not blow up your amp.
I wish i had $10 bucks for every Boogera story ive heard of something catching fire or blowing up.
Definetly a problem.

 

[houseofrock]

You get what you pay for. For a little more than the price of Boogera crap you can have something nice that will last & not blow up your amp.
I wish i had $10 bucks for every Boogera story ive heard of something catching fire or blowing up.
Definetly a problem.

I have two of these. 1 is 16ohm and the other is 8ohm. works well.