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celestion vox and impedance matching

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I've posted a variety of related questions here and on other sites, so this may seem vaguely familiar, but I've arrived at the following:

Background - I've had a '65 U.S. Vox Berkeley V8 tube amp for decades.  I got it with a Buckingham cabinet which I like and still use (2x oxford alnico 12s.) As part of a restoration project, I finally got a beautiful Berkeley cabinet and trolley, but it came from a solid state version which used different speakers. The "new" cabinet has a pair of 8 ohm Celestion 7424s, instead of the 16ohm 7442s the V8 would have come with. I will keep looking for Vox/Celestion 7442s, but it will probably be a long & difficult search, since the 7442's have achieved mythic status.

Question 1 - Since my 7424s are from same era as the holy grail 7442s and have N1B4 cone stamps, are they identical except for the impedance?  (Would they sound equally grailish?)

Question 2 - I have a half dozen 70V multi-tap transformers lying around that were pulled from very hi-fi N.E.A.R. outdoor speakers.
The primary wires are: Com, 128w, 64w, 32w, 8w, 4w. Secondary: Com, 8ohm, 4ohm.
My minimal web research (a dangerous thing) makes me think the secondary of these is simply an autoformer.  Can I use the secondary (only) as an impedance matcher?  In other words, if I were to completely ignore the primary taps, could I safely try out my 4ohm cab with my 8ohm amp by running the amp into the 8ohm tap of the secondary, with speakers fed by the 4 ohm tap?

Thanks very much.  Please forgive if I post the same question elsewhere.
Randy

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That's a thought, but replacing the OT of an otherwise 100% original ('cept some tubes and a few caps) 55 year old amp, just to audition a pair of speakers seems insane, sacrilege, or both.  I could get a different amp, too. 🙊

To be clear, I'm quite fond of this one and restoring it has been a labor of love.  I'm the lucky and proud owner of one of the sweetest sounding and absolutely THE most beautiful amp in the world.  It's in the eye of the beholder, I know. But just picture the back-line props of every episode of the Monkeys in living color.  (unblemished tolex, showroom shiny chrome trolley and knobs, trapezoid head, all orig from mid 60s w/ foot-switch and vinyl covers...)

It would be sacrilege to replace the tranny instead of getting the right speakers!  I've lived many years enjoying my alnico 12s with it and can continue for many more.  The questions are:

  1. How can I experience a pair of 10s I happen to have, that happen to be nearly identical to ones that seem highly prized?
  2. Is it worth any effort to do so? (WITHOUT changes to the actual amp)

Thanks

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see starting at paragraph 7: http://www.voxshowroom.com/us/amp/berk.html

tldr:

the tube versions used a 8 ohm cab (7442's in parallel?).

the newer solid state versions used an 4 ohm cab (bulldogs in parallel?).

as you must know, two 8 ohm speakers can be wired as 4 or 16 ohms, but not as 8 ohms...

here's their skinny on vox cabs: http://www.voxshowroom.com/us/amp/berk_spkr.html

(all my searches seemed to end up at this one website...)

p.s. - are your oxford's 8 or 16 ohm?  this website says the oxford gold bulldogs were used in the 4 ohm cab whereas the 8 ohm cab used the  7442's...

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HI GUYS

MYTHICAL CELESTION 7442 10 INCH C 15 OHMS & in Black stamped made in England and Celestion on each tab were the wires join.

WAIT THERES More ...They are housed in no less than the Original VOX PA CABINETS.

Circa 1966 with the chrome  legs and the black chequered cloth on one ...the vox sign on BoTh and all 8 speakers look undamaged. 

Now I have plenty pics as I will be selling both cabinets and when you see the beatles selling them and being used in Abbey Road I'm gonna sell to the highest  bidder. 

Ok let me suss the pics.

 

Peace

Oldskool

John

 

 

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12 hours ago, Oldskool66 said:

HI GUYS

MYTHICAL CELESTION 7442 10 INCH C 15 OHMS & in Black stamped made in England and Celestion on each tab were the wires join.

WAIT THERES More ...They are housed in no less than the Original VOX PA CABINETS.

Circa 1966 with the chrome  legs and the black chequered cloth on one ...the vox sign on BoTh and all 8 speakers look undamaged. 

Now I have plenty pics as I will be selling both cabinets and when you see the beatles selling them and being used in Abbey Road I'm gonna sell to the highest  bidder. 

Ok let me suss the pics.

 

Peace

Oldskool

John

 

 

 

You should really re-post this in the HC Classifieds section - first of all, because we ask that people not spam the discussion forums and secondly, because you'll have a lot better chance of people seeing it, since the classifieds are where they go when they're looking for gear, not the discussion forums. :)

Here's the link to the Amps classifieds section for you:

https://www.harmonycentral.com/forums/forum/52-amps/

Welcome to Harmony Central! :wave:

 

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