Marshall Origin 50H hum

[Ruslan S]

Good day. I recently got a brand new Origin 50H, which is my very first (!) valve amp. It works and sounds real great, with one minor issue: some hum noise (not too loud) from guitar cabinet as soon as I turn it on, without guitar plugged in and even on 0 gain/master volume. What can that be? Is that something I should be worried about?
P.S. I'm located in Ukraine with 220V/50Hz supply and no grounding at all, dunno if that's important.
Thanks in advance!

 

[marshalltsl]

The ground must be connected! This is the hum noise that your amp has.

to the forum.

 

[tce63]

As @marshalltsl says, use the ground.

And to the forum

Cheers

 

[marshalltsl]

You must use a grounded transformer. It gives you an artificial ground.
230va input 230vac output

 

[Ruslan S]

Guys, thanks A LOT! I will try that, will test with real grounding this weekend. Will drop results here, maybe this can be useful for someone else

 

[marshalltsl]

You must use a grounded transformer. It gives you an artificial ground.
230va input 230vac output

I have one that I bought 20 years ago for a band practice place that don't have ground conection.

Also you can make one if you have Iron radiators in your House and you can connected it into the land floor.

 

[Mitchell Pearrow]

Guys, thanks A LOT! I will try that, will test with real grounding this weekend. Will drop results here, maybe this can be useful for someone else

Yes it is useful and.
Welcome to the forum my new brother, please report back with your findings, as they are great amps.
Cheers Mitch

 

[BluesTone]

Good day. I recently got a brand new Origin 50H, which is my very first (!) valve amp. It works and sounds real great, with one minor issue: some hum noise (not too loud) from guitar cabinet as soon as I turn it on, without guitar plugged in and even on 0 gain/master volume. What can that be? Is that something I should be worried about?
P.S. I'm located in Ukraine with 220V/50Hz supply and no grounding at all, dunno if that's important.
Thanks in advance!

Hi Ruslan, just wondering if you ever found anything out about your origin 50 hum? Mine does the same exact thing you described, no grounding or electrical issues but when I switch it on there’s a low hum coming from the speakers. When I found your post, it got me to thinking that this may be normal.

 

[BluesTone]

Just wondering does anyone else’s Marshall Origin 50 Head hum through the speakers when you turn it on? I’m trying to find out if a small amount of hum is normal, thank you.

 

[solarburn]

Just wondering does anyone else’s Marshall Origin 50 Head hum through the speakers when you turn it on? I’m trying to find out if a small amount of hum is normal, thank you.

Yep. Mine does. Always has. Tube changes and bias adjustments haven't changed it either. Also cab changes didn't matter.

I don't find it killing my fun but it's there in the background. Ive heard worse.

 

[solarburn]

Since we're talking about humming Marshallz. Know what else hums just like it? My DSL40C when I switch to half power mode. Same hum. No hum at full power. Hum at half. It's always done that too no matter the bias/new tubes.

 

[BluesTone]

Thanks for that valuable information Solarburn, I’ve been wondering about it for quite some time. It’s good to know it’s normal, I was about to drop $90.00 on a matched pair of Tung-Sol EL34 tubes.

 

[solarburn]

Thanks for that valuable information Solarburn, I’ve been wondering about it for quite some time. It’s good to know it’s normal, I was about to drop $90.00 on a matched pair of Tung-Sol EL34 tubes.

Yah I always buy matched(usually apex matched)for amps with "one" bias pot. Tubes I've been putting in it have been closely matched. Still hummed.

I just swapped some new Svetlana 34's in and hum was the same. I've tried a few different power tubes for shitz and giggles and got the hum every time. I like to experiment.lol

 

[ThreeChordWonder]

Yep. Mine does. Always has. Tube changes and bias adjustments haven't changed it either. Also cab changes didn't matter.

I don't find it killing my fun but it's there in the background. Ive heard worse.

+1.

When it's working.

On the subject of which, can anyone recommend a good amp tech in the Houston / Austin / San Antonio area. I live in Houston but will travel to Austin or San Antonio for the right tech.

 

[solarburn]

+1.

When it's working.

On the subject of which, can anyone recommend a good amp tech in the Houston / Austin / San Antonio area. I live in Houston but will travel to Austin or San Antonio for the right tech.

Awh bummer man. Is it past warrantee? If not make Marshall take care of it.

Don't know any techs in your area. Hope it gets fixed!

 

[ThreeChordWonder]

Awh bummer man. Is it past warrantee? If not make Marshall take care of it.

Don't know any techs in your area. Hope it gets fixed!

I think it's still in warranty, I need to get a printout from GC to verify. Parts will still be covered, I think, but not labor.

What I'd like to do is have a tech who actually knows and understands old fashioned tube circuits go over it and make sure  everything is hunkey dorey, make all the recommended service mods, upgrade some of the iffy resistors, etc., not just fix the problem or swap one PCB out for another.

I just replaced all the tubes, but I'm still having the same issues: random sounds like it's being overloaded crackles when I strum, loud noises when I switch between low, middle and high outputs, some outputs not working at all, and now only seeming to work when the FX loop switch is engaged.

I'm going to have to sit down and catalogue them all before I take it in.

 

[jagrenet]

The ground must be connected! This is the hum noise that your amp has.

to the forum.

Agreed

 

[ThreeChordWonder]

You can buy an electrical outlet tester to check your wall socket ground is actually connected for about 12 bucks at Home Depot, Lowes, etc.
All you've got to do is plug the tester into the socket and the built in LEDs will tell you if you have a fault.

 

[Mike Sadler]

Mine NEVER hums... and no, it is not 'normal'. I think I see the pattern though... is everyone with hum issues in the USA? We have 240V here in Australia, and our earthing system is also very good... the US seems quite variable. If I had *just bought* an amp and it hummed (with no input cable, and especially no/low volume) I'd be returning it, but I know lots of my US mates have hum they can never seem to get rid of.

 

[Ronquest]

The transformers are coupling. This is a design issue of this amp. You may have hum from other things, but the fact is these amps have transformer induced hum and the hum exists even without any tubes in the amp.
The fix is to move the output transformer, live with it or sell the amp.