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I've never seen those myself but they look like "New", I wouldn't do anything to alter them until you find out for sure what model they are they are. There are some guys on AVS in the "Speakers-JBL Owners" thread that might know,http://www.avsforum.com/avs-vb/showthread.php?t=866797&page=379go to the above spot and post there and you might get some good input from those guys. There was a gentleman "Zilch" who recently passed away who could tell you with a glance at them exactly what you have there but those guys might be of help and a couple guys here might chime in.......enjoy!!! and welcome to AC!!!
It is probable that the original speaker was purchased for mono and later a duplicate was built when stereo came along. I bought a pair of Klipschorns many years ago that came to me with that as an explanation as to why they weren't an exact match. If that is true of yours, it would explain why one has the factory mark and the other doesn't.
That's a good point. IIRC, these speakers predate stereo.
Lansing soon developed a series of components enabling him to put together a virtual copy of the original Iconic system. These included a fifteen-inch theater-type woofer, a high-frequency driver, and a small multicellular horn. The driver, known as the D175, is still in the JBL catalog today. Lansing pioneered the use of four-inch voice coils for low-frequency transducers, and the D130 was the first loudspeaker to incorporate this. The D130 was developed in 1947 and with it the D101 was discontinued. The development of Alnico V material during the war years is what made the new design possible. Working with Robert Arnold of the Arnold Engineering Company in Chicago, Lansing was able to procure a magnet of reasonable size that could saturate a four-inch diameter gap with a field strength of about 12,000 gauss. Such a gap obviously had to be quite small, and the relatively large four-inch voice coil had to be built with a degree of precision that had been unknown in the industry. Other products designed by Lansing during the same time were the twelve-inch D131 and eight-inch D208.
Hey look what I found.http://www.hifilit.com/hifilit/JBL/1956-2.jpghttp://www.hifilit.com/hifilit/JBL/1956-5.jpghttp://www.hifilit.com/hifilit/JBL/No34-2.jpgSo your N2400 x-over is probably like the N2500 and 12db/octave, maybe for a different ohmage? So your old caps are screwing up the sound of both the tweeter and the woofer. What are the ohmages of the tweeter and woofer?Ken
Brian,If the speakers are operated without replacing the capacitors, there is a risk that there could be enough low frequency leak into the tweeter to do some serious damage. It might not be worth the risk to run them without replacing the caps. Bill
Where abouts in South City?
Ted, looks like you may have picked up a combo c36/c38 setup. They are quite nice, and will quickly get extremely loud. I have more then a few of the C series here in south county. The bullet tweeters are more than a little bright and overbearing, so I hold the view that loosing a few dB due to the aged crossovers may actually be a good thing, taming some of the shrill biting high.