# Princeton Reverb RI: Can I run an extension cabinet?



## White Horse (Feb 15, 2010)

Hi folks, 

I have a Princeton Reverb reissue, which I like, but I want a bit more bottom-end for gigs. So, I'm wondering if I can run an extension cabinet like a 2X12? 

The owner's manual says the amp's external speaker jack must be hooked up to a 16 ohm speaker while the internal speaker must also be hooked up to 16 ohm speaker. This baffles me. I understand two 16 ohm speakers create an 8 ohm load, but can't I just hook up the external speaker jack to an 8 ohm load? 

Or, if the internal jack _must_ be used, can I somehow combine them to run an 8 ohm 2X12 cabinet? 

Any help would be appreciated.


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## Voxguy76 (Aug 23, 2006)

Is it possible that by hooking up an external speaker, the internal speaker is then bypassed? This would make sense with the manual as both would be seeing a 16 ohm load.


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## parkhead (Aug 14, 2009)

Translation: They are saying they don't trust the OT with an extension cab and don't want to get sued when you cook the thing..
two 16 ohm speakers in parallel make an 8 ohm load 
the simplest solution is to rent or Borrow an 8 ohm 4-12 for gigs and disconnect the internal speaker 

What I would do...

replace the Output transformer with something Bigger 

ie a deluxe reverb OT or 

an allen to26 looks lie the ticket 

Allen Amplification - Parts Order Page

get a 10 inch speaker with a bigger magnet, and have your tech add 20mfd to the main B+ filter (max 60mfd with a tube rectifier) 

and hook up any cabinet you want 

you still have a 13 watt amp but now you have bottom end 

If this sounds too complicated to you, you don't really want bottom end 

I will add that I have done this "mod" upgrade to many amps 

the key is you need to like the amp you start with & for the most part 

it shouldn't be a "vintage amp" ... 

I have not used the allen OT but have a Deluxe OT in my 63 princeton
its a drop in replacement & my original OT is safely put away 
a previous owner cut the baffle for a 12 & the amp has a geunine 
60's vox alnico ...
With the deluxe OT I have gigged the amp at 3.2 ohms 
that is a 4 ohm 2-12 extension cab + the internal speaker
and run the amp on 10 all night ...
Deluxe OT's are cheap & its a 20 minute drop in replacement, and I have spares 
(I have yet to cook one !) 

You have to be careful doing the filtering upgrade since most tech's go crazy 
thinking more filtering = less noise
but the tone and touch of the amp disappear if you filter to heavily 

imagine a race car with no suspension travel and the lowest hardest springs
available ... great at the track, fatigueing and terrible to drive to work and back 

When adding filtering just bump it up a little at the power transformer 
ie add 30% at the B+ filter anywhere else will affect the "touch" of the amp

In the living room added filtering will make the amp harsher on the gig it will 
be a little tighter its always a trade off 


P


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## White Horse (Feb 15, 2010)

parkhead said:


> Translation: They are saying they don't trust the OT with an extension cab and don't want to get sued when you cook the thing..
> two 16 ohm speakers in parallel make an 8 ohm load
> the simplest solution is to rent or Borrow an 8 ohm 4-12 for gigs and disconnect the internal speaker
> 
> ...


I've got a Ragin' Cajun in it already. Is the Allen OT better than a Deluxe Reverb OT? And once I put this in I can run different loads without a worry? Thanks for your help.


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## parkhead (Aug 14, 2009)

email the allen people and ask Its supposed to be a further upgrade 

I've never used it ... but it looks like the solution 

I once had a Twin OT in a 59 deluxe it barely fit but sounded glorious ... talk about bottom and punch 

p


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