JBL 123A-1 professional woofer speakers working 12\"

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JBL 123A-1 professional woofer speakers working 12\":
$182.50

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This is a pair of amazingprofessionalwoofers jbl type 123A-1.That will go into studio monitor cabinets or other cabinets.They are 12\" speakers.The bass sound in these particular model is so incredible that you will be amazed( had a lot of fun with them and the deep low end sound that you can almost feel or even touch) will usher you into a new dimension of soundappreciation.I havealwaysbeen fascinated by speakers since childhood , and when I heard this particular model y was blown out of the water!!!!Have to put them for sale because I got married and need the extra cash. (I never dreamed that I will have to be forced to sell them) Maybe the buyer will let me listen to them once a year jaja.Well in a moreseriousnote: the quality control and craftmanship that was put into these Alnico 5 speakers was unheard of in its time, and that is why John Lansing was able to obliterate the competition, given excellent sound quality.These areprofessionalspeakers and will go into any of the professional cabinets that where designed for this kind of speakers (as an example the monitor speaker cabinets for sound recording studios)This sound is so amazing that you dont need a cabinet if you dont have one just put the speaker against a pillow and on top of a bed or against the rear seat of your car and you will see how your car will rumble..This kind of quality has endured the test of time, and as you can see in the pictures these units are in mint condition.Their are ideal for a speaker design project (by for example using them in a 60 liter enclosure for more efficient operation) or as a replacement for a non working speaker of the same sizeHere is some info about where these speakers can go:

The James B. Lansing L100 Centuryloudspeaker, the consumer version of the 4310 studio monitor, became the largest selling loudspeaker model of any company in the Seventies and more than 125,000 pairs were sold. By the end of the decade, recording studios in the United States used more of JBL’s monitors than all other brands’ monitors combined. Due to the materials used, the L100 drivers are as good today as when they were produced, but the overall sound can be vastly improved by modern crossover technology.

The kit is suitable for those JBL variants using the 123A woofer, LE5-2 midrange driver and LE25/LE26 tweeters, e.g. 4311.
For the 4310 (LE20 tweeter) you need 3 additional components.Read below.

Response from people buying the upgrade kit

Mail received 12 August 2011 from Mr. Jim Barthell, retired Vice-President of Engineering Administration at JBL:

I truly admire the work you have done to upgrade the JBL L100 Loudspeaker. It’s sort of like you’ve given an old man a new heart.
I am retired now, but I worked in the audio/consumer electronics manufacturing industry for forty years – from 1960 – 2000. During the 1960’s I was Vice-President of Engineering Administration at JBL. I am not an engineer – but I did direct the L100 development program. L100 Design Engineer Ed May was a very dear and close friend. I coordinated the work of industrial design consultant, Arnold Wolf – who, with Doug Warner, was responsible for the visual design. Arnold later went on to become President of JBL and my boss. Larry Phillips created maybe the best audio promotion program ever: “Wednesday for Trombones, Thursday for Drums.” Years later, when I was introduced to Mark Levinson engineer, Tom Colangelo – Tom – smiling when he heard about my past JBL work experience, simply smiled and spoke that now famous marketing phrase.
The best L100 story “never told” is that of JBL draftsman/audio enthusiast Carl Davis from Ottumwa, Iowa. Ed May told us all that microphone wind screen foam material would make an acceptable grille material. Arnold Wolf gave us stunning designs. The problem was that the foam industry was basically the packaging and filtering industry. Pressure cutting foam tolerance was about +/- .25 inch. No foam vendor could meet Arnold’s design requirements. Carl Davis, without degree, without assignment and working on weekends – was the first – in the entire industry – to discover that foam could be hot wire cut – and with the required precision. The L100 project had lingered more than six months in limbo while we struggled with the grille design problem.
Meanwhile, the L100 market got off to a head start when studios began ordering 50 to 100 pairs of walnut 4310’s. We all knew an unauthorized distribution process was under way.
Thanks for giving me a reason to look back, Jim Barthell

While enjoying the soundfrom newly renovatedJBL L26 Decades, I might as well start writing abouttheone and only, JBL L100 Century. A month ago one of my friends threw in these speakers, having bought them from an old fellow for 300 DKK (50 US $) - a total give-away. All drivers in mint condition and the cabs with minor scratches. Tweeter foam had gone but can easily be replaced from sellers.
I won\'t go into historical details on the L100 as so much can be found at:audioheritage.organd in particular about the L100 here:audioheritage.org
A rare opportunity to measure what the L100 did back then where I could only dream of owing a pair of these speakers from \"over there\". I don\'t recall the retail price, but they were very expensive. Having recently experienced theSEAS 503 kit, I now realise the 503 kit was actually a better speaker at that time. Quite similar in size and power handling, the 503 had a better midrange and a better crossover and the 33FWK bass drivers may beat the 123A drivers. But the SEAS drivers didn\'t have the gorgeous looks of the JBL drivers, the white-coated cone of the bass driver and the exquisite finish of the LE5-2 driver. I\'ve always had a week spot for the LE5-2 due to how well it is built. Take a look at how the dust cap is glued to the cone and the fine touch of paint around the edges. It takes great skills to make such fine work. However, the LE5-2 is not an easy driver as we shall see later.

This first partof the my L100 story will not engage in a new crossover, merely try to find out what the L100 was in terms of driver performance and crossover construction. And we might as well take a look at the original crossover right away, because it\'s simplicity itself: 8 uF to the mid and 3 uF to the tweeter. That\'s all! Both drivers connected via an L-Pad for attenuation. Mid connected with inverted polarity. Having a 12\" bass driver running full range is a bold choice and a lot of work must have gone into designing the 123A driver to produce a smooth roll off. The LE25 is a better tweeter than we might think, maybe not from measuring performance, but well equalised, it can deliver some excellent treble integrating well with midrange, actually better than many modern domes in my opinion. I\'ve recently bought some LE tweeters on : LE20, LE25 and LE26. Read here:troelsgravesen.dk

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JBL 123A-1 professional woofer speakers working 12\":
$182.50