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FDP Forum / Fender Amps: Vintage (before 1985) / Jensen C12N in a 75 Twin Reverb

Next 20 Messages  

usa metro detroit

Mar 19th, 2017 05:47 PM   Edit   Profile  

Jensen C12N IMO sound really nice in a Twin reverb

Removed the old Fender Oxfords from my 75 TR they kinda were bland... but not bad, .. tried some Eminence "Texas Heat's" those were just way too much. Made the base frequency prominent. (i.e. more than I cared for)

Had a Jensen C12N laying about, so I bought another and put both in my TR. Totally happy... Nice balance. The originals TR's had C12N's in them I know the new RI has C12K in them ?? (70 watts a pcs) wonder why Fender used the C12k?

Anyway... The Jensen C12N are a nice choice for a TR (at 50watts two of them handles the Twin's 85 watts just fine)

Contributing Member

American Patriot

About as ordinary as you can get.
Mar 19th, 2017 06:49 PM   Edit   Profile  

A C12N is just right for a TR. The last Twin Reverb I sold, a '66, had C12N's in it. I now have a '65 Pro Reverb with C12N's.

Mick Reid
Contributing Member


American-made in Oz!!
Mar 19th, 2017 10:46 PM   Edit   Profile  

I've always been a fan of Jensen speakers.
I had an original Blues Dlx that I put an old C12N in and it sounded great. So much better than the stock Eminence.
I later fitted 2 x C10R's in it and I loved that set up. I have a thing for 10's btw.

If I ever get the itch to do speaker swaps in my current amps (all stock with Celestions atm) I would definitely look at Jensens again.


usa metro detroit

Mar 20th, 2017 04:46 AM   Edit   Profile  

I was a little hesitant at first, the C12N being 50watts. Glad I did.

I just put some P12N ina 74 Pro Reverb (non-master) and they sound awesome! (and they are not even broke in yet!)

And now these C12N in the 75 TR! Totally dig them.

Here in the USA (on the internet mainly) Jensen gets a bad rap.. it's got to be from being bought out by an Italian company. (based on nostalgia type reasons) both the speakers I've just bought I really like and totally scratch that Fender itch.

Yea I hear Weber makes a better Jensen than Jensen. But I kinda shy away from companys that say they clone the original better than the orginal. People say "Jensens don't sound like Jensens." First, untill lately Fender hasn't put Jensen in thier amps, Second those famed Jensen of old are 45+yrs old. Who knows what those Jensens sounded like brand new? For me... these New Jensens sound great, very classic Fender and that's what I'm looking for.



Fender power to the people!
Mar 20th, 2017 07:06 AM   Edit   Profile  

Who knows what they sounded like when they were new?
That would be us old farts that played on them when they were new.


usa metro detroit

Mar 20th, 2017 06:15 PM   Edit   Profile  

So you can remember in the early 60's what brand new American made Jensens sounded like?

That put you close to 80, I wish I had that kind of memory...

I'm 50 and used to gig with Marshall JCM800s in the 80's and I can't tell for sure what they sounded like brand new...

IMO I like these Modern Jensens they sound great out of the box & will only get better as they age

(This message was last edited by pcalu at 09:14 PM, Mar 20th, 2017)



Mar 20th, 2017 10:07 PM   Edit   Profile  

Jensen's were made right up until 1972, when they went belly up. I had '68 Ampeg GU-12, in 1973, with a Jensen C12R. I assure you, the current Italian made C12R sounds nothing like the original.


usa metro detroit

Mar 21st, 2017 06:51 PM   Edit   Profile  

All I can say...

I've NOT had an amp with Jensens till now. I've always played amps with Celestions, Eminences or Oxfords. Having no preconceived notions, or nostalgia bias... I tried Jensens first time in my Black-faced 74 Pro Reverb. A pair of Alnico P12Qs right out of the box sounded amazing! Perfect fit! When those speakers are broken in, that amp is going to sound even better! (and to me that amp sounds like a 10!) I've never had a pair of speakers sound that good right out of the box (yea the amp probably has something to do with it.. but I think it's "Right speakers for the Right amp!") After trying Celestions, and Emineneces in my 75 Twin Reverb (also black faced) nothing worked. Celstions V-types were the wrong color of tone, and the Emeince Texas Heats had to much bottom end, resulting in the amp being muddy on the lower registers. I had a Jensen 2014 C12N that I pulled form the Pro.. bought another new one and dropped both in the Twin. WALA! What I heard is what I think a Twin should sound like! Again speakers sound really great right out of the box (all be it one speaker was already broken in)
love the vintage sound!

I think the modern P and C type Jensens are a real good fit in vintage Fenders, might not be good for other amps, but man they sound great with my vintage Fenders.

'Jensen® "reissues", after intensive research and analysis, are made to the same specifications as the original Jensen® speakers used by Leo Fender and others"

My exclellent results, my experiences with Jensens. I have no reason to doubht that statment.

(This message was last edited by pcalu at 09:00 PM, Mar 21st, 2017)

Steve Dallman
Contributing Member

Merrill, Wisconsin

Age is just a number...mine is big
Apr 7th, 2017 12:05 PM   Edit   Profile  

I put a new C12N in my 67 blackface DR and although it was glorious clean, with any type of distortion it produced harsh, strident, piezo-like highs that sounded awful and could not be eq'd out.

No amount of break in helped. Even a beam blocker did not help. I even doped the edge...then softened the dope. No change.

Then Joe Naylor of Reverend came to the rescue, and told me to remove the hard paper dustcap and replace it with a felt one. BINGO

That speaker went from sitting on a shelf to my favorite Fender speaker. It's been in my 65 PR (actual not RI) for several years now.

I've modded some other new Jensens with that hard paper dust cap. I use some rather stiff felt from a craft store. In all cases, the speakers still had bright, clear trebles, but lost the beaming, harsh highs when using distortion, be it amp or pedal.

Friends of mine did the same with their Jensens and all were thrilled.

I would prefer a modded new C12N to the originals.

FWIW, the C12K does not have the hard paper dust cap but a mesh fabric so does not suffer from the same strident high end of the C12N. I rather like the C12K.


usa metro detroit

Apr 7th, 2017 04:15 PM   Edit   Profile  

I don't hear that with the C12Ns in my Twin.

Sometimes it's the tone stack in the amp. I.e. not the right speaker for the amp...and the speaker is not a bad speaker. Just no matter what you do that speaker isn't going to work.. but its not the speaker. Case in point I tried some Emeinece Texas Heat (I know they are a good speaker I have them in another amp... wonderful speaker) but they just didn't gell in the Twin

Won't that dust cap soften with use and with age?

when you apply that felt what happens? Does it soften the treble like a Alnico? That would be cool... sort of a Ceramic-Alnico hybred. The million dollar question: "What's the long-term outcome of your modifications... will they hold up after years of playing?"

(This message was last edited by pcalu at 11:47 AM, Apr 8th, 2017)

Steve Dallman
Contributing Member

Merrill, Wisconsin

Age is just a number...mine is big
Apr 11th, 2017 07:36 AM   Edit   Profile  

I have speakers from the early 60's with felt dust caps that are in fine condition. I've never seen a felt cap deteriorate. I use adhesives that last.

The hard paper dust cap beamed a harsh treble (with distortion.) Replacement with felt smoothed that high end out. I've done this to many Jensens for myself and customers (I'm a retired amp tech) as well as friends.

There has been no downside. You are right. Some speakers just don't sound right in some amps. I dislike Celestions in Fenders. But a Jensen C12N SHOULD be a perfect speaker. In a Fender, and in my DR, it sounded great clean, but not with distortion. After the mod, it sounds great, clean or with distortion. I just replaced the old Jensen in our guitar player's 65 Ampeg Reverb Rocket. I can't remember if we used a Jensen P or Q, but it had the same hard paper dust cap. I did the mod to it, and our guitar player loves it. He isn't even interested in gettting the original Jensen reconed. (I may do it anyway.)



Apr 14th, 2017 08:21 AM   Edit   Profile  

The Jensen C12N is one of my favorite speakers.
I especially like the older American made ones...and in my experience a recone usually IMPROVES the sound of an old one.

It's a brighter sounding speaker and the cleans really sparkle. The overdrive is nice but a bit more buzzy than a P12N. If I had a particularly bright amp like a blackface Fender that I wanted to overdrive a lot I might go with a P12N.


usa metro detroit

Apr 14th, 2017 06:27 PM   Edit   Profile  

This is my opinion with lot of gear on the internet.

Guy X talkes crap about a product that he doesn't have a clue about... guy Y reads it and believes it and then repeats it to guy Z who then does the same.. Guys X is a hack doesn't know what he's talking about & guys Y & Z are too lazy to go check out the gear themselves. Fast forward on the internet a year and the what Guys XYZ have stated is now the TRUTH!

Case in point with Jensens.. SICA Altoparlanti the Italian company who owns Jensen, has maintained all along they have faithfully reproduced the vintage speakers.. To my ears thay have. Here is a link to a video that makes as good as a case that the SICA wasn't just using marketing hype.

External link



Apr 15th, 2017 09:03 AM   Edit   Profile  

Italian Jensen repros aren't the same as their American counterparts.

For example and American C12N Jensen recone kit will not work at all on an Italian Jensen because the coil is a different size.

Some sort of problem with Metric vs. English standard tooling.

There's also the fact that an older speaker magnet will change it's strength a bit as it ages.

I do think Italian Jensens come close and are a great improvement for a lot of amps using a cheaper speaker, but I still prefer a nice vintage one that's been reconed.

A touch less biting on the high end.


usa metro detroit

Apr 15th, 2017 12:50 PM   Edit   Profile  

Agreed guitarcapo... Agreed. But your talking about a 50yr old magnet and cone (in some cases) that's hard to replicate without paying huge big bucks as in Tone Tubbies etc (who make a Alnico that sounds like its 50yrs old right out of the box. For only $299.00 speaker lol...

For the record I'm not saying Jensen RI's are better than other speakers, I'm giving my opinion that Jensens are a good speaker and well worth using/trying.

I think these RI will soften up with age (why wouldn't they?) mine sounded darn good right out of the box and already have gotten warmer with the high-end getting soft

Makes sense they going to be in metric, they are made in Italy. Probably very little of the original materials are used in the RI. I can see them getting the design correct though, to where the speaker replicates the signature sound waves of the vintage speaker.

I've been using Jensens for a bit now and really enjoy them. IMO they give a real nice "Vintage" tone, i.e the Vintage Alnicos and the Vintage Ceramics.

Not new guitar playing, gear or speakers, been playing and gigging since 18 (I'm 50) What I am new to is Jensen.. being primarily a Celestion and Eminence guy.

I don't normally read internet opinions (with the Jensens RI's I just tried them.. found them quite decent. ) After reading some non-professional opinions on gear site like this... they have one thinking Jensens are real junk. Had me going huh? I also have seen people write RI's don't sound like the originals. The Video kinda debunks that notion that the reissues don't sound like the originals.

Another example of ya can't always believe what you see on the internet

Contributing Member


Jul 15th, 2018 10:53 AM   Edit   Profile  

I just like having a Blackface Fender how Fullerton put them together. Funny that way.


usa Thumb area Mi

Aug 5th, 2018 07:48 AM   Edit   Profile  

Update on SICA Jensen RI's Kinda a "Special Myth Buster's post"

After reading: "In the late 1990s, under a licensing agreement, SICA Altoparlanti, an Italian speaker manufacturer, commenced production of the legendary Jensen® speakers. These Jensen® "reissues", after intensive research and analysis, are made to the same specifications as the original Jensen® speakers used by Leo Fender and others."

Reading much on the internet about how these are not like the originals, I decided to do two things.

A) Delve into the world of speaker science to understand how a speaker works and...
B) Find out if SICA was being truthful in their claims.

After doing my homework on frequency graphs and Thiele-Small Parameter, I decided to look at the C12N as my base study.

Myth #1 SICA (Italian) Jensen RI can NOT be re-coned.


I was able after a simple search to order the re-cone kit for the Jensen RI C12N, along with the two re-cone kits for vintage Chicago Jensen C12N.

Jensen (Chicago) produced two C12Ns

C6969 (a seamed cone) & C8220 (a solid cone)

Examining the re-cone kits and external data i.e. Frequency graphs & TSPs and any "legit" sources on Chicago Jensens I could find. (few exist)

The Jensen Ris C12N have the same nominal diameter and the same voice coil opening of 1.5 as both the vintage C6969 & C8220.

The Jensen Ris C12N has the same seamed cone as the C6969.

The Vintage C6969: Voice Coil: 1.522″ inside diameter, 1.0″ form length, .375″ windings width, 8 ohms. Cup Spider: 4.0265″ outside diameter, 1.5″ VC opening, .275″ cup height

SICA/Jensen RIs: Voice Coil: 1.472″ inside diameter, 1.125″ form length, .375″ windings width, 8 ohms. Cup spider is 4.095″ outside diameter, 1.0″ VC opening, .225″ cup height

The there is a difference of .025 & .125 of an inch between the SICA/Jensen RI and the original C6969 and the cup spider. Same windings on the voice coils. & Both the Vintage Jensens C12Ns and the SICA/Jensen RI have is same magnet weight of 30oz.


Other than the Cup Spider.... the SICA/Jensen RI C12N is indeed a modern copy of a vintage C6969 seamed cone Chicago C12N. And as far as I know the closest in representation in production.

Now it Makes sense why Fender uses SICA/Jensen RIs in their top-shelf HW reproductions.

IMO.. (and this is me) After years of using RI C12Ns, I believe people who say they don't sound authentic, either have C8220s (& maybe some of these sound different than the C6969 seamed cone? IDK...) Or are forgetting they are comparing 50+yr old speakers to new one ???. Or are being topical to be trendy on internet forums like this...

There are Two negative critiques Jensen Ris C12Ns on the internet that I have read and both IMO are valid.

RI C12Ns don't do average to heavy overdrive. (I should point out neither do the original Jensen C12Ns) Pushing the speaker with average OD accentuates the classic American aggressive mids and high end of the speaker too much. This speaker is best suited for clean to light/moderate overdrive.

The long break in time. Sica also replicated the low efficiency of the vintage Chicago Jensen C12N. The speaker has a heavy doping this makes for a very long break in time. (upside.. cuts down on cone cry and ghost notes)

Fenderguru.com recommends speakers that are low in efficiency. They allow the amp to reach it's sweet spot at a lower volume, thus making it easier to play/work with. Huge plus! I use RI C12Ns in a Twin Reverb, makes managing the volume an easy task.

So there you go a detailed look at the SICA Jensen RI C12N.

love'em or hate'em... they are what they are

Contributing Member


Aug 6th, 2018 11:12 AM   Edit   Profile  

Thx for the intensive research, pcalu. Lived in Ann Arbor 10 yrs.

Contributing Member


Aug 6th, 2018 12:46 PM   Edit   Profile  

Nice deep dive!


usa Thumb area Mi

Aug 6th, 2018 06:29 PM   Edit   Profile  

Thanks. As one can tell the difference between the vintage C6969 and the RI are pretty marginal. Close enough where I think someone is really splitting hairs to say there is a difference mechanically

I'll add for the casual reader

Overdrive & the Jensen RI C12N.

What I found what works best is the tried and true Ibanez Tube Screamers. (or the Boss Blues Driver/ i.e. pedals of that nature) These dirt boxes shunt a lot of high frequencies and push a lot of mids.

I experimented with a lot of dirt pedals to see what the RI C12Ns responded best with.

I found transparent pedals like my Archer & by Blue Note (by J Rocket) let too many high frequencies through and was causing that high-end bite that so many complain about with the RIs. In fact, they just sound god awful through an RI C12N, same goes for heavy distortion boxes..

To my amazement... I found the more you dial up the mids on your amp, the more these speakers get sweeter.

My TR's EQ settings Treb 3, Mids 6 & Base 3.

Focus on the mids and these speakers bloom, get a dirt box like a TB.. No high treble bite, only cream and sugar..

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FDP Forum / Fender Amps: Vintage (before 1985) / Jensen C12N in a 75 Twin Reverb

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