Best Full Range Driver for Mini Monitor Size HT Use

[Melo theory]

Originally Posted by Ben_Tech

Thanks Melo.....

Since we are already talking about box design, I came up with a quick and dirty one for the A7.3 as follows:

Volume: 0.25 ft^3
Tuning: 65 Hz
Inside Dims: 8.5 x 6 x 8.5 in (HxWxD)
Vent: Slot 0.5" x 6" x 5.13" length @ mach 0.04

-3 dB at about 57 Hz.

3/4" thick MDF box with veneer on both sides and coated with borosilicate internally and stuffed with sheep's wool.

I'm also considering a solid hardwood box - I am pretty sure I can do it in layers - would be interesting and unique.

With the above rough design in mind, along with the promises of additional midrange detail (which I do want for vocal clarity) on the A7, and the likely crossover at, say, 100 Hz, do you still think the A10 is the better choice?

Go here for tvrgeeks stuffing report...
Stuffing test report

I think the design is great.
But I'm sure Dave (planet 10), will be bye to discuss MDF with you

I think the 10.2 is better for the reasons I stated, but the 7.3 is great as well, and cheaper.

[Ben_Tech]

Originally Posted by Melo theory

Go here for tvrgeeks stuffing report...
Stuffing test report

Thanks for the link. Recycled blue jeans, huh? Or, I could just treat the walls internally with a dappled latex tile adhesive and sand mixture and call it done.

In any event, I need to decide for sure which way to go with the driver (A7 or A10). Decisions, decisions....

[planet10]

Originally Posted by Melo theory

But I'm sure Dave (planet 10), will be bye to discuss MDF with you

Maybe better than nothing, but with all those moving from MDF boxes to OBs maybe not.

MDF is common in speaker building because it is cheap & easy to finish (ie cheap to finish). Not because it has any significant audible benefits.

dave

[Melo theory]

Hey, I would definitely go with BB on my builds, and I have with the "event horizon" but it is 3 times more expensive than MDF here. Also, I have to order it from woodcraft and it needs to be shipped to me. So no mistakes or I have to wait for another shipment.
When I start commercial sales, I will be using BB

[Ben_Tech]

Originally Posted by planet10

Maybe better than nothing, but with all those moving from MDF boxes to OBs maybe not.

MDF is common in speaker building because it is cheap & easy to finish (ie cheap to finish). Not because it has any significant audible benefits.

dave

While this is off topic to the thread, I thought MDF had the benefit of high mass for the thickness. High mass cabinets are the traditional approach for good sounding cabinets used by most high end companies, no?

[planet10]

Originally Posted by Ben_Tech

While this is off topic to the thread, I thought MDF had the benefit of high mass for the thickness. High mass cabinets are the traditional approach for good sounding cabinets used by most high end companies, no?

Hign mass is a myth (lots of myths started by marketing departments to help them shrink costs). If you have 2 materials with the same stiffness, the light one is better. MDF is both less stiff and denser. A good receipe for energy storage. On a system with not much DDR not that big a deal, but as you push for greater DDR, the low level time smeared ooze of sonic energy from an MDF cabinet makes it impossible to go beyond a certain level.

Also when shopping, you can't directly compare thicknesses, you should be comparing 3/4" MDF to 12mm BB. 18mm BB to 1 1/4" MDF.

Particle board is better than MDF, but harder to work with.

dave

[Ben_Tech]

Originally Posted by planet10

High mass is a myth
dave

OK, you have convinced me. I've used many sheets of MDF over the years building speakers, but no more.

Baltic Birch if I go the easy route on these.

However, I'm thinking of something more artistic made out of layered exotic hardwood.

[planet10]

Originally Posted by Ben_Tech

I've used many sheets of MDF over the years building speakers, but no more.

Baltic Birch if I go the easy route on these.

However, I'm thinking of something more artistic made out of layered exotic hardwood.

It should be noted that, if we used MDF, we could probably cover our needs by rescuing offcuts that go into the bin at Chris's work.

Shop grade BB was our material of choice, a decrease in consistency has had us move a bit up-market to Oregon made Murphy Ply (more $$ goes into the material and less on the boat ride across the Atlantic).

We are playing with solid woods, you have to know what you are doing, and the results can be surprising. We are now in the midst of prepping for a direct comparison of the saem (small) enclosure in murphy ply (or maybe BB scraps), Locust, Yew, Black Walnut, Douglas Fir (a pine) and western red Cedar.

A very stable, exotic sheet material that is VERY good is stranded bamboo plywood (vertical block surfaces are next down in quality and still good, solid or horizontal surface probably not worth pursuing). I'd like to add a set in that material to the test above but to get 1 sheet of 12mm we have to buy 10 sheets, just not in the budget. 18mm is the commonly available size, but far too think for the box in the test.

dave

[Ben_Tech]

Thanks Dave, I'll be looking forward to that test.

I was thinking Purpleheart from South America.... I've used Bloodwood from the same continent before..... pretty stuff. Finding enough of it is the hard part.

I've also been looking at those Bamboo cutting boards. Have you considered those before? I'm sure you have.

[planet10]

Finding enough of it is the hard part

One of the reasons why the widest variety of species are in the smallest boxes. (depending on timimg i might be able to add Garry Oak to the above list)

Chris' set.

I've also been looking at those Bamboo cutting boards. Have you considered those before?

Yes. Breadboard style solid chunks, and when you actually calc the per ft^2 cost, more expensive than the ply. Might be good for an accent ie supraBaffle or some such.

dave