Advice needed: '63 Vibroverb reissue

[king-albert]

I just picked up a '63 Vibroverb reissue this weekend as a "Thanksgiving present" for myself. I love it so far but...it breaks up around 3.5 volume. I'm looking to get some more clean headroom out of it.

The amp has the stock 10" Oxford reissue speakers in it. I've read unfavorable HC reviews about these speakers and I'm looking to replace them. So I'm looking for advice on 10" speakers that will increase the headroom on this amp.

Side question: Can I hook up my 8 ohm Avatar 2x12 speaker cab to the extension speaker out on the back of this amp? Will it cause any damage? Will this possibly increase the amp's headroom (it's loaded w/12" Eminence Legends).

Thanks in advance for any help from you guys.

[topbrent]

While it is not a perfect impedence match....go for it. It really wont hurt a thing. Loads of people do a 50% mismatch on fender amps regularly. The have had extension speaker jacks for decades, and plugging in another speaker immediately goes to mismatch without ill effect.

That avatar speaker setup will sound great with that amp:AOK

[king-albert]

Thanks for the advice. I'm still somewhat uneasy with this. I tried it out last night and played for 20 minutes or so and it sounded amazing! With the tone I was getting, I could have played it all night. But I was still very apprehensive about it so I stopped.

[topbrent]

It's good to be concerned, but it's doubtful that you will hurt it at all.

Fender amps are spec'ed to able to handle the mismatch. If the factory was seriously concerned about it.....there would not be an extension speaker jack.:jo

Play your amp and enjoy it.:AOK

[jkats]

If you 've read the HC review, you've seen what I've done to my 63 VVRI. The biggest improvements are in upgrading speakers and power tubes. On the speakers, I used Jensen RI C10Qs. If you find those too harsh on the high end, you could use the heavier and more expensive Weber 10F125 or 150 -- probably one standard and one "T" cone -- two standard 10F150s may be too dark, if my experience with a 12F150 is any indication. As to power tubes, a paitr of SED 6L6s work well for me.

I also changed the bright capacitor (C-11) from 47 pF to 120pF, but not everybody likes the additional highs. If you have an early VVRI, they were underbiased from the factory, and a Fender Technical note available online (Google the amp) indicates the proper resistor (R58) value to use, or you can have a tech install an adjustable bias (usually a $50 job).