8 driver SLA center channel crossover?

[Fastskiguy]

So I found a thread that talked about using 8 of these in the curved SLA center channel array and am building it up

https://www.parts-express.com/4-Treated ... hm-299-320

My question is about the crossover.....should I use the crossover for the 9 driver array like in the plans or the 8 ohm crossover in the TLAH plans? And then what about the 8 tweeters, I'm using these 8 ohm guys here

https://www.parts-express.com/Goldwood- ... shopping=F

Thanks

Joe

[Bill Fitzmaurice]

I believe that thread showed how to wire them and what alterations of the crossover component values are required.

[Fastskiguy]

I am having a hell of a time finding the thread with the info....would it be insane to just add a 9th tweeter inside the box and wire it up with 9 as in the plans? The 8 midbass line....I've got that under control. Thanks again

Joe

[Bill Fitzmaurice]

You must use a crossover that's been configured for the impedance load. Since that driver is 16 ohms the low pass filters in the plans won't work.

[Fastskiguy]

I was thinking I'd just use the 8 ohm low pass TLAH crossover for the midbass line...would that work?

Joe

[Seth]

Bill, it looks like he's dialed in on the 16 ohm mids and is inquiring about how to best cofigure the accompanying 8x 8ohm tweeters.

[Fastskiguy]

Yeah that’s exactly it thanks Seth

[Bill Fitzmaurice]

The high pass filter in the plans is for 8 ohm tweeters.

[Seth]

The plans include instructions for either a 6 element array or 9 element array, but not an 8 element array.

In the other thread you said to use 4 ohm tweeters, 4 in series to get 16 ohms, parallel the 2 banks to get to 8 ohms, which would certainly be the way to go. Except that, in this case, he's using the 16Ω mids, which dictate the 8 element array, but he also has the recommended (8Ω) Goldwood tweeters... which is where the question arises.

Given the drivers on hand, seems to me he can either wire the tweeters up as a 4Ω or 16Ω circuit and select appropriate crossover component values based on that. Which way would be the optimum way to wire this up? 4Ω, 16Ω, something different?

By the way, Joe... Very clever of you to consider wiring up a tweeter inside the enclosure to enable the 9 driver wiring solution and resultant 8Ω load. As "outside the box" as it is, it may not be a ridiculous idea.

[Bill Fitzmaurice]

TBH I got confused with what he's doing, talking about TLAH and SLA and an eight driver SLA at that. Using eight 8 ohm tweeters at 4 ohms the component values would be 6.6uF, 20uF and 0.12mH, +/-10%. I'd wire them for 4 ohms as you'd rather cut the HF EQ to balance it out than boost it.

[Fastskiguy]

Awesome, thank you guys!!

Joe

[Fastskiguy]

I happen to have the stuff for the 9 tweeter line and an extra tweeter so I might just try throwing an extra tweeter in the box and see how it goes but I sure appreciate the exact components, thanks again.

But today I found a woodworking issue. The driver frame is a little bigger than the recommended size and it doesn't quite fit. I'm thinking...sand the bottom of the driver frame or route a little, narrow groove where the frame "dips into the bottom", if that makes any sense. Is there a better way I'm not seeing? Thanks

Joe

[Bill Fitzmaurice]

That outer frame could be squared off with the right tool. This is definitely a 'measure twice, cut once' situation.

[Seth]

I'd use an abrasive blade in the table saw and make a sled jig to make the cuts perfect and identical. I have a hadful of those drivers, and best I can tell from the photos, trimming that portion of the driver frame doesn't look like it would interfere with the gasket.

[Fastskiguy]

OK got it, thanks!

Joe