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I just spit my drink out of my nose.

Sorry about the thread necro. I have a some n00b questions about using those planar tweeters in the SLA pros.

Should I wire them in series or parallel? What if I used 3 per cabinet? Is that a better idea than 2 per?

I'm using the Eminence PX2-3K5 crossover, will I need to use the L-pad to attenuate the tweeters? The 4 Alpha-6a's are 400w, two tweeters would be 200w. If I drive these speakers at full volume, would I risk damaging the tweeters? (That's why I'm thinking 3 per side)

On the tweeters, how do I tell the difference between the positive and negative terminals? One is small, one is large.

DJ Nada wrote:Sorry about the thread necro. I have a some n00b questions about using those planar tweeters in the SLA pros.

Should I wire them in series or parallel? What if I used 3 per cabinet? Is that a better idea than 2 per?

I'm using the Eminence PX2-3K5 crossover, will I need to use the L-pad to attenuate the tweeters? The 4 Alpha-6a's are 400w, two tweeters would be 200w. If I drive these speakers at full volume, would I risk damaging the tweeters? (That's why I'm thinking 3 per side)

I believe the eminence crossover is configured for 8 ohm drivers... which means you'll need to use either 2 planars wired in parallel, or 4 in series/parallel (2 banks of 2) to arrive at an overall 8 ohm load for your tweets. Bill would know much better than I, but when I built the Tlah Pro my 4 banks of 5 tweets came out to a 6 (ish) ohm load, for which Bill mentioned my fancy Fostex 8 ohm L-pad would not work correctly.

DJ Nada wrote:On the tweeters, how do I tell the difference between the positive and negative terminals? One is small, one is large.

The smaller is almost always the negative terminal. You may need to experiment with switching the polarity anyway depending on how your response is at the crossover frequency.

Wiring in parallel would give me an impedance of 4 ohms, no? What bad thing would happen if I used the 4 ohm speakers with a crossover designed for 8 ohm speakers?

DJ Nada wrote: What bad thing would happen if I used the 4 ohm speakers with a crossover designed for 8 ohm speakers?

Poor sound and blown drivers.

Bill Fitzmaurice wrote:Poor sound and blown drivers.

So how do I wire it then?

Well, since I can't bi-amp these, and nobody has a good answer for me here, I'm going to go with 4 ribbon tweeters per side. Raises the price quite a bit, but they should sound awesome. Right?

In unknown territory is the reason for a dearth of answers. I hope it's great. But I do think you probably should have designed a custom crossover.

DJ Nada wrote:Well, since I can't bi-amp these, and nobody has a good answer for me here, I'm going to go with 4 ribbon tweeters per side. Raises the price quite a bit, but they should sound awesome. Right?

You tell us. When you follow the plans the guaranteed outcome is known. When you deviate from them you're on your own.

Bill Fitzmaurice wrote:You tell us. When you follow the plans the guaranteed outcome is known. When you deviate from them you're on your own.

Thanks, you've been really helpful.

DJ Nada wrote:

Bill Fitzmaurice wrote:You tell us. When you follow the plans the guaranteed outcome is known. When you deviate from them you're on your own.

Thanks, you've been really helpful.

Let's see here.....you buy plans, then ask the man who designed them to tell you how to change them so the components that YOU decided to use would work.....

Did you really expect an answer other than what you got?

Everyone here, including Bill, will help you build these designs......but, not your designs.

^ Aww c'mon Bruce,
What you said there is totally logical...

Grant Bunter wrote:^ Aww c'mon Bruce,
What you said there is totally logical...

sorry....I know you aren't used to that from me.....

Seeing how he's a speaker expert that I bought stuff from, yes I did expect something other than "you're on your own." Are modifications discouraged or something?
Whatever, I'll figure it out using some other resource. Bring on the BFM fanboy hate.

Bill has a rate for custom design work. It is more akin to heart surgeon rates than the mere price of a CD of plans. The rest of us do it for free but not if you're gonna cop an attitude.