110dB 3 Way

[sumsound]

Hey all I made the mistake of posting in the full range speaker section, not realizing that meant 1 tiny speaker in a big box.

So here is my repost of my first official thread here on DIY Audio

This is my first thread here besides what I wrote in the tapped horn section many moons ago.

This is a little 3way I designed a while ago and have had on the back burner for a little bit.










My design criteria was to have all sealed boxes, and have enough SPL head room to reach Full Scale Cinema SPL (with Bass Management). In a small to medium room. I also wanted the cabinets to have as broad a polar response, including polar at xover points.

One of these little guys will do 110dB SPL @ 1 meter. From 80Hz to beyond 20kHz (-3dB @ 55Hz).

I chose components that have very linear response curves in their intended band pass.

Originally I designed a passive Xover, but it was very complex and hard to make since My woofers are 4ohms mids 8 ohms tweeter 4 ohms. It was going to have some very expensive inductors and Capacitors in it.

I ended up using a 3 channel ICE amp with on board DSP and went all active.

The drivers I used are

2 Peerless 830667
1 SEAS MCA15RCY
1 VIFA DX25TG05-04

Absolutely stunning sound!

[bzfcocon]

Looks interesting, but...
- you might get some significant diffraction effects from the "baffle" (or lack of it ) with unsmooth transitions
- the "110dB" title is a bit msleading: I thought at first that this would be the sensitivity of your speakers - rather, it seems to be the max SPL.

[sumsound]

Yah I guess its a little misleading.

But 110 dB is pretty good max spl for a home environ (actually its more like 113 for some of the range.)

I made most of my edges 1/2 round so its not a sharp transition.

Where do you think the most significant defraction happens 1/4 wave from center to edge?

I was thinking of getting some yellow board ( 6lb fiber glass board) and making a damping baffle.

That should absorb any would be defracted energies and prevent pattern narrowing since the energy would be absorbed instead of acting like a baffle.

Thoughts?

[sdclc126]

What is the crossover network design? Crucial part of any speaker system.

I would widen the cabs all around and flushmount the drivers.

Great choice of drivers and excellent effort - no small feat to build something this ambitious. Congrats.

[454Casull]

First thing that popped into my head was "holy crap diffraction".

[sumsound]

The ICE amp has a nice 96khz DSP I'm using all 4th order LR.

As well as various Parametric EQ's almost exclusively on the HF.

By the way here's some great information about "Baffle Diffraction"

http://www.linkwitzlab.com/diffraction.htm

I think I'm Ok with my design the way it is. It looks like the Larger the Baffle the more ripple in response.

[sumsound]

So whats worse having more ripple and peaks from a larger Baffle or less from having a smaller Baffle.

I did see the rise around 3.3kHz from the Vifa ~ 4"baffle. I used some Parametric to take care of it on axis.

If I really wanted to do it right I would have made spherical enclosures but, that's not very easy.

I don't think there is going to be too much significant diffraction in the woofer or mid range.

I think most of it is really going to happen in the tweeter range.

But I could be wrong.

[wigginjs]

Where did you get your xover / amp modules?

[sumsound]

If I told you I'd have to kill you...

[BionicSniper]

looks great! what's the benifit of the push-pull on the woofer?