That's too bad. My SAMMI 3 inchers go down to an FS of 102, with a 3.6 mm Xmax(huge for such a small speaker). But I cross them at 165hz. In a group of 17 per side, they sound fabulous.

It was one of the requirements when I built the array. The mids needed to be able to cover the range from about 150 to 2500. Handling only 5.8% of the total sound per side, they do great, and with EASE.

My preference is to do the designing first rather than the buying first. I did purchase one of them to start. I hooked in up in a tube cabinet, and disconnected the woofer from the other speaker. So they were handling low volume. It was the SAMMI running full range against a Vifa BC and an Audax tweeter. As long as the volume was low, in a direct comparison, both my wife and i agreed that the Sammi was more transparent and had greater clarity.

Marlboro

I am hip to the SAMMI drivers too.
Some look quite impressive, and prices seem very reasonable.
They SURE have a large selection.

I have nothing against Korea, been driving Daewoo's for years.
Hyundai's are reliable cars, not so sure about Kia's ?

I know you are using fiberglass in your tuves, but have you ever considered Kapok ?

Do a Google Search for Kapok speaker damping, and the US Patent will come up.
Check out the Patent claims ?

I learned about it from my Kid.
He does Bass Competition, and many of the Bass sound off champs use it instead of Fibefgalss and Wool.

I have used it, and feel it is superior to fiberglass.

But, that is only my opinion, and have just my seat of the pants feel to back me up.

The PVC tubes might allow easy damping experiments in your design.

You can try different materials, and graduated density of the materials themselves ?

I wish you lived here in Tampa, I would love to hear those speakers!

BTW, when you said CHEAP drivers, I thought of some transistor radio cheapies, LOL

The SAMMI May be a cheap driver, but it is FAR from a shit driver.

The X Max alone of the little guys tells you that!

You got one hell of a deal, jumped on it, and now you got your babys!

As an audiophile, I share your excitement.

I was gonna buy Fred in Texas Needles array he had for sale, but he is in Texas, me in Florida!

A DIY rule: Don't fall prey to marketing propaganda

I wouldn't use a driver that has a weak bottom and top end
because it can create more problems to solve, assuming
the driver you want has those issues.

If you want to build a line array, have you auditioned any arrays
to establish a reference point?

What is wrong with a coned driver 4" - 6" mated to a line of
tweeters $4 - $118 ?

The first is in the 6th edition of Vance Dickason's THE LOUDSPEAKER COOKBOOK. In this he determined after extensive testing the the most attenuating stuff between acoustistuff, pillow fill and fiberglass was fiberglass. And the most effective density is 4 lb cu ft. There are some caveats but they don't apply between 500hz and 4500 hz.

The second is a study sponsored by Rod Elliot on his site that showed the effectiveness of the insulation is dependent on the size of the filament. Pillowfill and acoustimass ar int he vicinity of .05 mm and fiberglass is .01. Acoutical fiberglass is even better at .005.

Marlboro

SUMMARY OF THE INVENTION

One object of the present invention is to provide an acoustic damping material which does not suffer from the limitations of the known art.

A further object of one embodiment of the present invention is to provide a sound attenuating material suitable for use in a loudspeaker enclosure, comprising kapok material, the kapok for reducing enclosure resonance and driver resonance.

The use of the kapok material is an alternative material that comes from the seed of kapok trees "Ceiba pentandra". This material is a natural fibrous material and is relatively inexpensive. The kapok material also has a very low density and thus is ideal for acoustic damping. By selection of the appropriate amount of kapok, the result is lower resonance within the enclosure. It has been found that by making use of the kapok that the resonance is greatly reduced relative to other materials. In addition, the kapok is essentially uninfluenced by the heat generated within the enclosure as the speaker drivers are used. This is in marked contrast to synthetic materials, particularly acoustic foam, which inherently would experience property changes due to thermal degradation.

I WAS going to build an array, but a "DEAL" came uo locally on these used VMPS RM 40's.

I have had them over a year, and I just can't seem to make them sound right.

Yeah, I can get em to sound decent on SOME stuff, but then they change radically on other stuff.

I also own 14 other pairs of speakers, including B&W 801's Von Schweikert VR 4 JR's, and JBL L 7's.

All these speakers seem to sound decent, if not good, on most material.

The VMPS are not like that, when you set their levels for one recording, other recordings sound bad.

I REFUSE to believe that they are simply "more revealing".

I have owned Electrostats for many years, and never had this problem.

Plus,, I owned Magnepan MG 3A's with long ribon tweeter,a most revealing speaker, and they did not sound like this.

These VMPS came up used here local for a fair price.

I do.

They are hi-passed by the manufacturer at 200Hz.

They sound good, .. but are a bit soft on top