Mod 12-70

Mod 12-70

General Characteristics
Nominal Overall Diameter 306 mm 12 in
Nominal Voice Coil Diameter 38 mm 1.5 in
Magnet Weight 640 g 23 oz
Overall Weight 2.4 kg 5.29 lbs
Flux Density 1.16 T
Thiele-Small Parameters
Nominal Impedance 16Ω
Voice Coil DC Resistance RE 3.53 Ω 5 Ω 12 Ω
Resonance Frequency ƒS 74 Hz 78 Hz 83 Hz
Mechanical Q Factor QMS 14.63 13.77 7.84
Electrical Q Factor QES 1.20
Total Q Factor QTS 0.9 0.89 1.04
Mechanical Moving Mass MMS 30.6 g 29.6 g 30.3 g
Mechanical Compliance CMS 151 µm/N 141 µm/N 125 µm/N
Force Factor BxL 7.23 Wb/m 8.28 Wb/m 12.56 Wb/m
Equivalent Acoustic Volume VAS 51.7 lt. 48.1 lt. 42.4 lt.
Maximum Linear Displacement XMAX ± 1.5 mm ± 1.5 mm ± 1.5 mm
Reference Efficiency nO 2.1 % 2.09 % 1.88 %
Diaphragm Area SD 490.9 cm2 490.9 cm2 490.9 cm2
Losses Electrical Resistance RES 51 Ω 67.7 Ω 80 Ω
Voice Coil Inductance @ 1kHz LE 0.43 mH 0.58 mH 1 mH
Constructive Characteristics
Magnet Ferrite
Voice Coil Winding Copper
Voice Coil Former Epotex
Cone Material Paper
Surround Material Integrated Paper
Dust Dome Material Non-treated Cloth
Basket Material Pressed Sheet Steel
Electrical Characteristics
Nominal Impedance 16Ω
Rated Power 70 W 70 W 70 W
Musical Power 140 W 140 W 140 W
Sensitivity@1W,1m 96 dB 97.5 dB 96 dB
70 watts
Available in 4Ω, 8Ω, 16Ω

The MOD12-70 is loud, dynamic, and well defined. It has a defined warm crunch response to overdrive distortion.

Guitarist Description
Loud, dynamic, and well defined. Has a defined warm crunch response to overdrive distortion
Bassist Description
Straightforward, bottom-heavy punch
Sound Samples
Want a more in-depth demonstration of our speakers? Try our Jensen speaker demonstration.
Having trouble playing our sound samples? Access the files directly.
Specification Sheet
Product Dimensions
User Reviews

The stock CTS ceramic speakers on my 1980 LAB Series L5 were far from bad, but a little lacking in high end and with a little too much lower midrange for my taste. According to reviews and its frequency response chart, the MOD 12-70 would theoretically cure these slight shortcomings. Indeed, it worked! This amplifier is now everything I've wanted. My main guitar is a stock CS Jazzmaster with heavy flatwounds, and I mostly play with a clean or lightly distorted sound (a DOD 250 gray clone and a Fulltone OCD are my main sources of dirt, with the occasional use of a Turbo RAT), but on some songs I use flat-out fuzz (Zvex Fuzz factory and a Superfuzz clone). I also use a lot of complex rhythmic delay (emulating early tape delays like the Meazzi), which tended to confuse things a bit with the old speakers. But with the Jensens, every single sound I use is articulate and well-defined. This might not be the best choice for blues players, but these speakers work well for pretty much everything else, in my opinion. I have not tried (and will not try) mid-scooped metal sounds on them, but I'm pretty sure they'll handle that too, as they seem to have a very controlled and tight low end.


Totally awesome Speakers. Very transparent. Allows the amp to shine uncolored. 


I just want to say that the pair of 12" MODS I bought and installed in an older Kustom cabinet sound fantastic. I have used many Jensen products over the years and they have always been my first choice. The reason is simply - they are the best. In my opinion anyhow. I have never been dissapointed with any Jensen speaker I have ever had. You can hand them a hefty beating and they hold up well. They will remain my first choice.

William in Benton, KY

I've been playing guitar for nearly 50 years and designing and building speakers systems for musicians for more then 40 years. I bought a new Trace Elliot Bass amp a few years back that had a Jensen MOD12-70. It ended up in my Fender Deluxe, exactly the sound I've been searching for for years. Now I've got another MOD12-70 and P12Q, they make all other speakers sound muddy (no not Mr. Waters). All my amps are being changed to Jensen. If it ain't broke don't fix it.

Reinhard in Gehrden, Germany

I installed a Mod 12-70 in my Lab L3 and i was immediately knocked out by the sound - the low end was tighter and the mids were more complex. Clean or distorted it was the sound I had wanted for years. On a whim I installed a Mod 8-20 in an old Peavey Rage 158 - the sound opened up with more lows and mids and volume. This small 15W amp is now my go-to for small rooms and recording.

Matt Richards

I've used the Mods. Love the 12 incher. Hope to be able to use more in the future.