Could any recommend a good replacement for an aging Jensen 12" (AlNiCo, I think) that is installed in my ca. 1960 tweed Gibson GA20T Ranger amp. The amp is approximately equivalent to a Fender Deluxe of the same period, with two channels with two inputs each, one with a tremolo circuit.
It's such a nice-sounding amp, but the old Jensen seriously farts out in the lower end and has no headroom. Nowadays I am into cleaner sounds and more technical picking than I was even a few years back and I want this amp to be able to handle surf styles at moderate volume.
I'd like a more 'hi-fi' speaker which works well with a small amp like this.
Thanks!

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Dope? Ribs? What are you observations of the sound of this speaker, tubeswell?
I know the 12A 125A is a copy of the original Jensen – but will it make the amp more gigworthy? Like,more bottom end, less breakup at volume?

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I cheaped out and got an Eminence Cannabis Rex, 50W capacity, for $77 + tax, delivered in 36 hrs.

Still breaking the cone in, but right away the heavier new driver brings back some clarity and oomph to the 20 W Gibson that the puny P12Q didn't deliver – especially with the Gibson Reverb III dialed in. The wet signal was so distorted it was unpleasant and the overall lo-fi sound was really discouraging me from playing the amp.

Installing the new Cannabis Rex, I had to torque the right 6V6 tube to clear the very broad magnet housing. The tube is still not entirely clear of it but now it only presses gently against the rubber gasket surrounding the magnet. I foresee some problems eventually with that tube jimmied like that, especially if vibration is transmitted. I folded aluminum foil as a heat sink between the tube and the gasket.

Now I can turn the amp up all the way without overmuch distortion and modulate volume with picking for a smoothly compressed sound. Fuzz works less well than overdrive with the setup. I haven't tried tape delay yet. The Gibson GA20T is a very musical two-channel amp with excellent onboard tremolo. An A/B switch gives me access to both of the differently-voiced channels: Bright w/tremolo and Dark w/o. The Ranger is comparable to the Ampeg Jet and the more famous Fender Deluxe. I'm glad to have something surfable that's smaller and less loud than my Twin.

I haven't noticed anything amiss using a speaker with twice the capacity of the amp's output. One thing I do hear, that also happens with my 12W Gretsch Electromatic Twin, is that there are basically 3 volume levels available. The amp doesn't get appreciably louder from half-cranked to dimed. Only way to go to "11" is with gain stage pedals, of which I have plenty.

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I do have a box full of tubes so I might win after all when I get electrocuted through my flatwounds when this happens.
It's not much pressure, it barely touches the fat rubber grommet surrounding the housing. I just can get it altogether clear unless I can modify the baffle angle or cant the tube socket permanently. Ever done that? I imagine I would have to drill out the rivets, mount the socket with an angled baseplate and re-rivet it back together.
tubeswell wrote:

JObeast wrote:

Installing the new Cannabis Rex, I had to torque the right 6V6 tube to clear the very broad magnet housing. The tube is still not entirely clear of it but now it only presses gently against the rubber gasket surrounding the magnet. I foresee some problems eventually with that tube jimmied like that, especially if vibration is transmitted. I folded aluminum foil as a heat sink between the tube and the gasket.

Yes I agree there will be problems. I wouldn't count on the bottle's glass envelope lasting very long with all the heat and vibration, and once it fails there's the killer voltage still present on the plates, which will be touching the speaker magnet, which if it is metal, will be bad to touch.

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I had one of those awesome amps once too, a two-tone.the tweed version is super-valuable now, hardly 'undervalued' the way Gibson amps all were 15 years ago.

I might do something about reducing the baffle angle a few degrees so I can get correct clearance for the magnet surround. It's nice to have a working 20-watt amp for a change, so I do't have to run the 85 or 100 w Twin every time my fingers itch.

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I understand the that you like the C-Rex speaker but I would not modify a vintage amp to allow tube clearance. You might consider reconing the vintage Alnico Jensen or finding something else with a smaller ceramic magnet to clear the power tube. The ceramic magnet would be typically cleaner when driver hard.

Keep it Drippy Brothers and Sisters!

Does anyone have experience with the Weber 12F150's bell housing – how it compares with the dimensions of a Jensen AlNiCo like the P12R? Apparently it fits Fender Tweed Deluxe amps perfectly (wider cabinet than the Gibson GA20T) Or the NeoMag 12"?

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JO:

The Weber 12F150 doesn't have a bell housing. At least the ones I've seen didn't. It's ceramic magnet, a big, flat magnet in the back. So it takes up space in a different way. Not as deep, but does go wider at the back of the speaker, than the typical alnico with bell housing.
MD

Tone Tubby!!!

-BAM BAM-

You can replace the paper dust covers in the Jensen C12Ns with hard felt and the fizzy, ugly tone when using OD and distortion will go away. They will sound more like vintage Chicago C12Ns.

You can get hard felt at a fabric store or order precut discs from Weber.

Just sayin'

Keep it Drippy Brothers and Sisters!