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slowpat
03-30-2018, 06:31 PM
Trying to put everything back on the Minigon C46 as I just got the cabinets refinished and woofers refoamed. The previous owner installed the LE10 and the LE30 into another system, so when I bought the Minigons, the drivers and the crossovers were provided to me with custom made baffles. Based on my understanding, the drivers should be connected to the LX3 crossover’s LF and HF wires. The crossovers I have included a Tru Ohm 20 resistor in parallel on the HF and a large coil(?) in series for the LF. Is that a mod of the time?

dadofshane
05-03-2018, 11:30 AM
I think you are right. I have never seen a recommendation from anyone to add on or change the circuit on the crossover for this system. I have heard that the LE30 was not a very good sounding tweeter and it was discontinued shortly after it came out. I believe the resistor on the HF will reduce the HF volume, and the coil or inductor on the LF will limit the low frequency but I don't know by how much. I would listen to what you have with and without the extra inductor and resistor, then make a decision which sounds best.

It seems to me, to tune a crossover today, you need to analyze the frequency response starting with good mics and end up in a computer program, then adjust the circuit peaks and dips, to attempt to get a flat response. I don't have enough knowledge or equipment to do this, so I tend to use the stock components that JBL recommends. But that said, I read at this site that there are options that are good, and I trust most of the people at this site for their years of knowledge and experience.

I have never listened to a LE30 so I don't know what's wrong or right with it. It may just be a matter of taste or hearing. You could sell the LE30's for a lot and replace them with something better and put money in your pocket. If you use them, and blow them, you will pay a lot to replace them, I don't think they are repairable because there are no parts available . I might ask if there is a compatible JBL tweeter to replace the LE30 with? The LE20 has been matched with the LE10 but with a different xover.

Places like Kenrick upgrades some of their JBL speakers with beryllium dome tweeters occasionally with good results, but it is again, it's a matter of taste or sound. In adding different tweeters you will probably need a different xover circuit to balance the sound unless you find a tweeter with the same output specs as the LE30, but I can't find any specs on the LE30. I did see that the crossover frequency of the LX3 is at 1kH. Someone with the equipment could test a LE30 and give specs on it, then it may be possible to match it to another tweeter.

You have a valuable and cool looking speaker. Sorry if I strayed from the original post too much. good luck and I hope you enjoy your music through JBL speakers, Mark