Speaker system gurus. Help. SWR content.

[MuthaFunk]

So I have been slowly upgrading my SWR Baby Baby Blue 110 combo:

Upgrading my SWR Baby Baby Blue II 110 Combo (long w/pics)

gerryjazzman has been most helpful in that thread but I wanted to start a thread a little more specific to the crossover and speaker system as I have some new questions that could apply to other bass cabs.

While looking into replacing the Le-Son tweeter in my SWR combo I found the polarity of the tweeter was wired in reverse polarity from the woofer. I know on my old JBL Summit L300 speakers the horn driven mids are wired in reverse polarity from the tweeter and woofer intentionally. All the documentation I've read on Piezo Tweeters says to wire them up in the same polarity as the woofer. What's the deal? Is this perhaps an assembly flaw from the fine "hand crafters" at Fender or does this make sense?



The Le-Son tweeter says "high efficiency dome tweeter" on it and model LJ. All SWR documentation says it's a TLX-1 piezo tweeter. In my upgrade thread gerryjazzman suggested I put a ohm meter across it to note if I read a coil resistance or infinity like a piezo. From what I've read about the Le-Son piezo's is that they have a built in transformer. I've measured a resistance of about 6 ohms. Can anyone tell me if this is a dome tweeter or a piezo with a transformer? The Le-Son brand has been out of business for a while and it seems as though all documentation has been removed from the net.

If you guys have any insight to the Le-Son brand or the SWR crossover circuit and respective polarities I'd like to hear it.

[Matthijs]

Mostly the polarity is switched because of the fase shift caused by a crossover. With just the one cap in front of the tweeter normaly the polarity does not need to be reversed. Reversal is normal for a 12db/2nd order crossover. I've never heard of piezo vs dome tweeter having anything to do with this.
Maybe the transformer you mentioned is a filter coil built inside the tweeter? If that's the case it might form a 2nd order filter together with the cap.

As long as you're upgrading: a steeper filter might be a good thing as one cap offers very little protection.

[MuthaFunk]

Yes I plan on upgrading the crossover as well. My ears tell me the crossover frequency is currently set very high and the purpose of the upgrade will be to get more sizzle from the horn down to just below 4KHz...

The whole piezo vs dome tweeter thing is just an unrelated question since I'm taking it out no matter what. I was curious as the more I looked for info the more interesting these LeSon tweeters got. There's only archived forum talk about them and the odd reference to the built in transformer that works in tandem with a specific cap recommended by LeSon. I would really like to get some info on it. I've tried looking into the internet archives to see if I could pull http://www.leson.com.br/tweeters.htm out but I wasn't able to get it to work.