JBL K120

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sahlomonic

sahlomonic

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I got this in a Seismic 1x12 with a Crate BV60 for freaking $50 this week. No idea what this speaker is intended for or how it sounds, but I'm trying to see if anyone here has experience with them at all?

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Sam Braintheory is a big fan of these. He’ll be chiming in guaranteed.
 
I think it's like a D-120

Both designations have an Alnico magnet, but the design is slightly different.

"K" series has more RMS capability, but "D" series apparently has a rounder sort of tone.
 
I think it's like a D-120

Both designations have an Alnico magnet, but the design is slightly different.

"K" series has more RMS capability, but "D" series apparently has a rounder sort of tone.
Sam says the K has huge lows.
 
All the vintage 12" JBL's are great speakers. You should check the number on the cone to see if it's original or not (very important). I find the K's need more volume to do their thing vs others, but sound great once loud enough and have a more low mid presence vs the other JBL's IME

JBL's have very big, tight, punchy lows, very sharp, aggressive, intense highs, (high and lows that no Celestion's get) and very scooped, hollow mids. They are to me some of the best vintage speakers (especially the orange D120F's), but they need sometimes the right cab or other speakers mixed to get the best results to work with their hollow mids and intense highs. My 2 cents would be don't give up on them if you don't like them at first. When used well they're amazing

The price you got it for is a steal regardless if the cone is original or not
 
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I think it's like a D-120

Both designations have an Alnico magnet, but the design is slightly different.

"K" series has more RMS capability, but "D" series apparently has a rounder sort of tone.
I find actually the D's to sound sharper and punchier/tigther (at least for the orange back D120F's), but really vs most Celestion any of these JBL's will come off pretty sharp and aggressive in highs. If you want a rounder sort of tone stay the hell away from any JBL LOL
 
I find actually the D's to sound sharper and punchier/tigther (at least for the orange back D120F's), but really vs most Celestion any of these JBL's will come off pretty sharp and aggressive in highs. If you want a rounder sort of tone stay the hell away from any JBL LOL
They work great to blend with a Greenback, tho'

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They work great to blend with a Greenback, tho'

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They do, particularly the 20w Greenbacks, but they work well with a bunch of different speakers. My favorite combo so far has been with Redbacks on top and either D120F's or E120's on bottom. Those Celestion’s I think fill in the mids the JBL's lack
 
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They do, particularly the 20w Greenbacks, but they work well with a bunch of different speakers. My favorite combo so far has been with Redbacks on top and either D120F's or E120's on bottom. Those Celestion I think fill in the mids the JBL's lack
The JBL D-120s remind me of the Altec 417-8H

Very efficient speakers.
 
The JBL D-120s remind me of the Altec 417-8H

Very efficient speakers.
Yeah the JBL's and Altec's sort of sound like cousins to me. I find the JBL's still have more low and highs, but the Altec's are more warm, woody and less scooped. I don't like the 417H as much, but the 417C and 417B are some of my favorites, top 3
 
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Those K's have been harder to find for me than the D series. The ones I have seen lately were exorbitant. So unless you get a deal from someone who doesn't know or care. That is my favorite JBL and favorite all time speaker because it takes a lot more abuse than a D series will and still gives the classic tone. I would def hang on to that speaker especially if it's in good cosmetic shape also. NICE score.
 
Those K's have been harder to find for me than the D series. The ones I have seen lately were exorbitant. So unless you get a deal from someone who doesn't know or care. That is my favorite JBL and favorite all time speaker because it takes a lot more abuse than a D series will and still gives the classic tone. I would def hang on to that speaker especially if it's in good cosmetic shape also. NICE score.
I'm happy you found one !

You told me you'd been looking for the D for some time.
 
Just an FYI guys....
A lot of JBL's are reversed phase.
Before mixing them with other speakers, you need to check the cones are moving in the same direction with a battery click.
You'll most likely have to wire the JBL's in reverse when wiring them with other speakers.
 
Yeah the JBL's and Altec's sort of sound like cousins to me. I find the JBL's still have more low and highs, but the Altec's are more warm, woody and less scooped. I don't like the 417H as much, but the 417C and 417B are some of my favorites, top 3
I have my 2 120F orange frames in with 2 Altec 417Cs. Great combo.
 
I have my 2 120F orange frames in with 2 Altec 417Cs. Great combo.
I find those combos can be cab dependent, but I preferred in mine both of those either as full quads or with 20w GB’s (heritage is what I had in 8 ohms to use with) or RB’s to better complement their voicings
 
I find those combos can be cab dependent, but I preferred in mine both of those either as full quads or with 20w GB’s (heritage is what I had in 8 ohms to use with) or RB’s to better complement their voicings
The upper mid zing of the Altecs go great with the scooped 120s, in a Marshall B cab.
 
The upper mid zing of the Altecs go great with the scooped 120s, in a Marshall B cab.
Altec’s across the board IME (B’s, C’s and H’s) are very subdued in the uppermids (you might mean higher frequencies that add zing?) and part of their unique hollow character in that region that I also hear in RR and Santana’s recordings, but that also might be why imo they can work very well with Marshall’s and my SLO. Both JBL’s and Altec’s have that American flat/subdued midrange (JBL’s just a lot more so), which is why I felt they actually weren’t the best functional match, at least in my KW cabs

As a whole quads there’s a nice cohesiveness to their sound I find and with the right Celestion fill in the mids and upper mids they lack
 
Altec’s across the board IME (B’s, C’s and H’s) are very subdued in the uppermids (you might mean higher frequencies that add zing?) and part of their unique hollow character in that region that I also hear in RR and Santana’s recordings, but that also might be why imo they can work very well with Marshall’s and my SLO. Both JBL’s and Altec’s have that American flat/subdued midrange (JBL’s just a lot more so), which is why I felt they actually weren’t the best functional match, at least in my KW cabs

As a whole quads there’s a nice cohesiveness to their sound I find and with the right Celestion fill in the mids and upper mids they lack
We hear differently; the JBLs in my cab are clearly scooped while the Altecs are not. To me, it's a great combo. But, maybe my Cs are a little different than yours? The 417Hs I had, are WAAY more mid scooped than my Cs. Huge difference there.
 
Its odd because even though I hear differences in my Altecs, according to Bill at Great Plains Audio, who is THEE go to guy, the 8C,8H, Etc are all supposed to sound the same. Yes, different construction but for the most part "Supposed" to be identical sounding. I have never had it done but I wonder if re-magnetizing some of these would bring them in closer to spec. When I asked Bill about it he said as long as it sounds good then you're good so I left it alone.
 
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