"Into The Abyss", Tweeters in low places

[TN Allen]

It's worked well for me. 16 gage Aluminum also works well. There are 2 additional advantages. If a 1/4" Corian round is used, and is partially set into the back of a guide blank, it can be used to locate the guide in a pocket in the sacrificial surface for milling. For example, a 4" diameter Corian disc can be glued into a shallow pocket on the back of the guide blank before milling. The part of the 4" disc protruding drops into a sacrificial surface 4.01" pocket. This assures the guide contour is concentric to the disc. It also works well when milling multiple guides. The .01" is clearance for fuzz that results from milling plywood or MDF.

The second advantage is that the tweeter can frequently be mounted on a similar 4" disc, and then both are mounted to the disc glued to the guide.

[xmax]

I got a little distracted, hopefully I will have some other sexy curves today.

[KEtheredge87]

New toy? Looks nice! I'd be distracted too!

[xmax]

Yup.

[xmax]

The testing has resumed, here is the RST in Pete's Elliptical WG on axis and 30 degrees off axis.

[xmax]

This is the HD from 10hz to 22K!!! (RST on Petes Elliptical WG)

[xmax]

Wavecor
Satori Ring Ceramic Magnet


SB29SDAC

Slowly gathering data, these all have Pete's Eliptical WG and have their faces ripped off.
Starting @ 2K LR4 and each color is 100-200hz per step down. As you can see the HD
rises as the XO frequency is lowered. Once the correct transfer function is applied to
filter the tweet and correct the rise in mid response the HD will be lowered drastically

[KEtheredge87]

That Wavecor looks awesome Hard for me to tell how audible the dip in the satori at ~13Khz or the bump up above 10K in the SB29 would be. I'm sure all of them are excellent options... and here I am splitting hairs over which one graphs the prettiest!

[xmax]

That Wavecor looks awesome Hard for me to tell how audible the dip in the satori at ~13Khz or the bump up above 10K in the SB29 would be. I'm sure all of them are excellent options... and here I am splitting hairs over which one graphs the prettiest!

As Pete and I were talking about it is interesting to see how the different domes behave in the guide, since the Wavecor usually has it's own
guide it seems they took it into consideration, I'm certainly not sure how, but the measurements were all done within 30 minutes with no
change in the set up. Another thing that is very interesting is how low the RST can go, with extremely low distortion. I am currently revisiting
it in the elliptical WG.

[xmax]

Yes there are wrinkles in the top end (easily workable if a issue) that said there is no other way to describe
Dayton's new RST 28s performance in Pete's WG is as good as it gets. Subjective views may vary.

[guitar maestro]

What are you planning to X them at when it's all said and done?

[scottq]

Would you be interested or willing to test some other tweeters if I send them? I think I have some Morel MDT-30s, MDT-39s, CSS LD22s, Wavecor TWsomething, Vifa D25AG35s, and probably a few others laying around. In the interest of collecting some more data...

[Head_Unit]

Once the correct transfer function is applied to
filter the tweet and correct the rise in mid response...

Now, my understanding is you are using the waveguides to increases the low end of the tweeter response and then essentially use a higher cutoff frequency with a low slope to even that out. On the other hand, if you wanted to use that sensitivity, something like Audyssey *ought* to correct the HF droop. At least that's my understanding. Thoughts?

I find this a really interesting thread because I've long dreamed of moving to higher sensitivity drivers in-wall.* That restricts depth. For HF that seems to mean either tweeters on waveguides or very expensive ribbons. Here I see some not-so-deep not so expensive possibilities. Yay!

*I know, not optimum, it's all about furniture and layout. Actually in-wall eliminates a set of first reflections which in another house did quite nice things for the sound, even though the Luxman in-walls were just like B+ grade. And I'd open the rear wall so at least there's a possibility for interior treatment. Then I find myself wondering about in-wall subwoofers (multiples since that REALLY limits the performance) or in-ceiling...

[xmax]

Would you be interested or willing to test some other tweeters if I send them? I think I have some Morel MDT-30s, MDT-39s, CSS LD22s, Wavecor TWsomething, Vifa D25AG35s, and probably a few others laying around. In the interest of collecting some more data...

Yes, no problem.

[xmax]

Now, my understanding is you are using the waveguides to increases the low end of the tweeter response and then essentially use a higher cutoff frequency with a low slope to even that out. On the other hand, if you wanted to use that sensitivity, something like Audyssey *ought* to correct the HF droop. At least that's my understanding. Thoughts?

I find this a really interesting thread because I've long dreamed of moving to higher sensitivity drivers in-wall.* That restricts depth. For HF that seems to mean either tweeters on waveguides or very expensive ribbons. Here I see some not-so-deep not so expensive possibilities. Yay!

*I know, not optimum, it's all about furniture and layout. Actually in-wall eliminates a set of first reflections which in another house did quite nice things for the sound, even though the Luxman in-walls were just like B+ grade. And I'd open the rear wall so at least there's a possibility for interior treatment. Then I find myself wondering about in-wall subwoofers (multiples since that REALLY limits the performance) or in-ceiling...

Something like "Audyssey" is generally designed for FR correction in the low end as far as I know. That said EQ is EQ whether in the passive XO,
or boosting with a active setup, as long as the results sound good I'm happy.

In wall (or "soffit" mounted for us studio rats.) can do all sorts of good things including eliminate diffraction. Although most housing does not have
walls designed for this sort of thing, with both construction and optimum driver position/angle.

More testing tonight including the TX32 in the same guide.