Argh! Speaker touches tube!

George · Post by **George** » Thu Jun 17, 2010 6:05 pm

The magnet on my new speaker is so deep and wide that it now makes actual contact with one of the power tubes. Is this acceptable? The tube still fits and every thing.

benecol · Post by **benecol** » Thu Jun 17, 2010 6:57 pm

Nope. That's not good long term.

laterallateral · Post by **laterallateral** » Thu Jun 17, 2010 7:35 pm

I've heard somewhere that tubes being in very close proximity to magnets causes them to go microphonic prematurely.
I don't know if that's true and if so, to which extent but considering the components inside of tubes are made of metal and the functioning of tubes relies on electron flow, I can't imagine direct contact with a magnet to having any useful application...

Other than that, though. I wouldn't move the amp around too much. Like, at all. Tubes banging on metal and all...

George · Post by **George** » Thu Jun 17, 2010 9:05 pm

I fired it up for a few seconds just to see what the new speaker sounds like more than anything. It didn't seem right knowing it was touching the tube though, part of me was nervous the whole time. Tube got really hot too.

Speaker goes back. Bummer.

dub · Post by **dub** » Fri Jun 18, 2010 1:38 am

Maybe try front mounting the speaker?

Will · Post by **Will** » Fri Jun 18, 2010 7:04 am

dub wrote:Maybe try front mounting the speaker?

Brilliant. Try this!

But yeah, the speaker will rattle the insides of the tubes apart if it's making contact.

Post by **Doog** » Fri Jun 18, 2010 7:42 am

Could you not build up the lip of the "speaker hole" in the baffle by like half an inch or so, bringing the speaker forward?

George · Post by **George** » Fri Jun 18, 2010 8:22 am

It's already front mounted unfortunately.

I suppose I could build the lip up as Doog suggested but if I did that it might be "touching cloth" with the grill so to speak. I Can't really build up the grill because it's already flush with the edge of the cabinet.

I'll check tonight, if there's an inch or so space between the speaker and grill I'll look further into it. It's the 2nd day of my 7 day "no quibble return policy" though

dub · Post by **dub** » Fri Jun 18, 2010 9:48 am

Rubber washers/spacers around the screws between the speaker and the baffle maybe?

You could try and take the chassis of the amp out of the shell and sit it on the top and play through the speaker safely to see if its worth the hassle. You may as well come out of the situation with an impression of the speaker.

What's the amp?

George · Post by **George** » Fri Jun 18, 2010 10:10 am

Amp is a Sound City 30C Mark 6 (very small and densely packed with flush edges).

Speaker is an Eminence Cannabis Rex.

Rubber washers might be a plan but I'll need an inch or so to get a safe distance from the tubes which may end up sitting further out than the grill. I'll experiment with sitting the chassis atop the amp tonight. See if it's all worth it.

George · Post by **George** » Fri Jun 18, 2010 4:50 pm

The speaker grill frame hugs the speaker so I've not go no way of using the washers. I've had to resign myself to the fact that I'm gonna have to return the thing.

Going up for sale in Classifieds too over the weekend. Why not eh?