Question for the Fender amp gurus!

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KRamone27
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Question for the Fender amp gurus!

Postby KRamone27 » Tue May 11, 2010 7:01 pm

Does anybody know what grade of pine was used on the 50s' tweed amp cabinets? measurements of a 2X12 cab would be nice as well but not 100% needed. Thanks

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Re: Question for the Fender amp gurus!

Postby dubtrub » Tue May 11, 2010 7:43 pm

I recovered a 72 Champ amp and it was a crappy grade of knotty pine.

Here's a site with the dimensions of a Bandmaster speaker cabinet. http://www.ampwares.com/amp.asp?id=17
Danny Ellison

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Re: Question for the Fender amp gurus!

Postby KRamone27 » Wed May 12, 2010 5:50 pm

dubtrub wrote:I recovered a 72 Champ amp and it was a crappy grade of knotty pine.



That's what I was afraid of. Thanks for the link Danny. I'm thinking of down sizing from a 4X12 to a 2X12.

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Re: Question for the Fender amp gurus!

Postby KRamone27 » Sun May 16, 2010 5:30 pm

Not Fender amp related but I need some help. My Marshall JCM-900 has been acting funny lately and one of the power amp tubes isn't glowing as brightly as the rest. Mainly what the problem is that when I'm playing the sound fades in and out like there is a power drop. Could dull glowing power tube be the culprit? I'd like to know before I go spending $70.00 on tubes.

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Re: Question for the Fender amp gurus!

Postby Veenture » Mon May 17, 2010 12:50 am

KRamone27 wrote:Could dull glowing power tube be the culprit? I'd like to know before I go spending $70.00 on tubes.
Kevin, is there no way of having a suspect tube tested before deciding to replace it (music store etc.)?
Good luck.

Paul

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Re: Question for the Fender amp gurus!

Postby GattonFan » Mon May 17, 2010 5:13 am

Remember when - you could just take your tubes into a store and plug them into a tube tester? Does anyone still offer that service???
So many guitars; So little time ..

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Re: Question for the Fender amp gurus!

Postby Mr. Bill » Mon May 17, 2010 12:49 pm

If you switch the tubes around, does the less glowing one work in a different socket or does it still glow less? And by glow, do you mean the orange filament glow or something else?

Have you tried cleaning the FX loop sockets? Or the tube sockets? Or the controls?

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Re: Question for the Fender amp gurus!

Postby KRamone27 » Mon May 17, 2010 3:47 pm

Mr. Bill wrote:If you switch the tubes around, does the less glowing one work in a different socket or does it still glow less? And by glow, do you mean the orange filament glow or something else?

Have you tried cleaning the FX loop sockets? Or the tube sockets? Or the controls?



No I haven't tried switching the tubes around at all but the pots are a bit scratchy but not enough to effect anything but I'll spray some deoxit in them and see if that helps. And yes I'm talking about the orange glow at the bottom of the tubes. And I have never used the effects loop at all would this effect the tubes at all? Thanks

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Re: Question for the Fender amp gurus!

Postby zarfnober » Mon May 17, 2010 4:50 pm

KRamone27 wrote:Does anybody know what grade of pine was used on the 50s' tweed amp cabinets? measurements of a 2X12 cab would be nice as well but not 100% needed. Thanks


Yep, knotty pine, the baffleboards were just regular plywood. You can get clear pine at Home Depot, about $3 a foot. BTW, it's 3/4" pine.

I can make you any Fender/Marshall style cab you want, opened my shop just last week and showed some cabs at our booth at the Chicago Vintage Show this past weekend , sold a ProTV 15" and a Bassman cab. Website will be up by end of week www.rockometeramp.com with photos.

Rocco
www.rockometeramp.com Vinatge spec American and British style cabs, custom cabs, recovers, regrills and restorations.

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Re: Question for the Fender amp gurus!

Postby Mr. Bill » Tue May 18, 2010 9:33 am

KRamone27 wrote:And yes I'm talking about the orange glow at the bottom of the tubes.

That's the filament or heater of the tube. Differences in the manufacturing process can cause them to look different, but usually if they light up they are fine. If you do see a dramatic difference in how bright the glow is after moving the tube, then there is a problem with the socket.
KRamone27 wrote:And I have never used the effects loop at all would this effect the tubes at all? Thanks

No not the tubes, but it can cause the amp to cut in and out or cause the volume to rise and fall. The return jack has a contact that is normally closed, that completes the signal path through the amp. If this contact becomes oxidized or dirty it can cause the resistance of the connection to increase causing the signal to drop out. This can cause a complete signal loss or just a drop in volume.


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