BillFitzmaurice.info

A couple more pics of driver layout

Nice progress.

That IS very tight. WOW

How wide are these in the end?

6 3/4" wide at the top of the baffle with the wings in place. The drivers are 6 1/4" outer diameter... yes, very tight.

Thanks for this. There haven't been a lot of Davids built, and I'm very interested to see the construction of one. It's on the tuit list. Has been for, say, the last 4 or 5 years.

Aw shucks,

I used to have a "To It" coin I could have sent you so you could get it done.

NOW I'VE DONE IT! D@mn it! I buit and mounted the electronics then closed the cabinet. Now while laying out the electonics for the next cab I see that I got a 15mh coil from PE instead of the 10mh in the plans and in my order. Nobig deal except I ALREADY CLOSED THE CAB LIKE AN IDIOT. Truely I am my worst enemy. Now I did test the electronics prior to install. I fired up the David today and it sounds good but a bit sterile. I am guessing that the larger coil is moving the low pass down under 100Hz. I will get a proper coil and replace the wrong one but look where I put them. IT WILL BE FUN WORKING IN THERE NOW THAT THE FRONT IS ON.
DAMN IT!

baronvonsteve wrote:IT WILL BE FUN WORKING IN THERE NOW THAT THE FRONT IS ON.
DAMN IT!

There's plenty of room in the woofer compartment.

Thanks for the encouragement, Bill. I did not make an access cover on both sides and the low pass is mounted on the side without a cover. You can bet I will be putting one in now!
BTW How does the substitution of the 15mh coil for the spec'd 10mh unit change the crossover frequency?

baronvonsteve wrote: How does the substitution of the 15mh coil for the spec'd 10mh unit change the crossover frequency?

It will cause a response loss in the midbass.

That is what I'm hearing. The midbass seems weak. Just for my own knowledge, is this a reduction of the midbass performance in the subwoofer section or in themid section of the MTM? If it affects the midbass driver in the MTM how does that happen since this is an error in the low pass unit connected to the sub?
Thanks in advance, Bill.

baronvonsteve wrote:That is what I'm hearing. The midbass seems weak. Just for my own knowledge, is this a reduction of the midbass performance in the subwoofer section or in themid section of the MTM? If it affects the midbass driver in the MTM how does that happen since this is an error in the low pass unit connected to the sub?
Thanks in advance, Bill.

It's reduction in the midbass output from the sub.

Thanks, Bill. Now I understand a bit more.
New coils on the way. I will post some pics in a bit.

I thought the woofer and sub cross around 160ish. Meaning thats where both play around. So does that mean that the midranger woofer doesn't play well by itself?

I know the sub will play the midbass easier but I figured the mid woofer could play to around 120hz just fine....NO?

I am just wondering. Two mids verse a horned sub wont compare but maybe I am looking at this wrong. Thanks.

Sorry about your luck Baronvonsteve. I have been having the same type of luck with my Ikea kitchen lately.

Any pics of the progress?

baronvonsteve wrote:Thanks, Bill. Now I understand a bit more.
New coils on the way. I will post some pics in a bit.

If you still find the midbass thin parallel 20 to 30 uF across the 150uF cap in the midrange filter. Your drivers have more Sd and xmax than than mine, so their high pass frequency can be dropped a bit lower. And if you haven't broken in all the drivers that has to be done before they'll sound right.

Once again; Thanks, Bill. How does one break in the Midbass drivers? I know how to break in the sub driver. I will add the caps to the mid crossover.
Here are pics of the build thus far.