Jims 3 way speaker build

[jimbones]

Hi all, sorry for the delay. Between Hurricanes, illness and things taking a bit longer than anticipated I anticipate that I will be ready to start posting the fun stuff next week. This will be the drivers mounted in the cabinet and doing measurements. This is where I could use some guidance. Until then I just have a few things ti button up. Thanks. Ohh and more pics too

[jimbones]

A progress photo of the cabinet ready to accept drivers. Should start Monday.

[Drummer]

Wow, that veneer is yummy! Is that spalted maple, Jim?

[johnny5jz]

They are looking great!! Can't wait to see the finished product!

[jimbones]

Wow, that veneer is yummy! Is that spalted maple, Jim?

Yes!!Wormy Maple it is. It is not veneer it is solid wood. Thanks.

[Wolf]

Warning, the lip from the top panel will cause some major diffraction.
Wolf

[Billet]

Will an edge like this be audible or just measurable? It certainly looks nice.

[Wolf]

In my Cecropia Supreme build it was very audible (3/8"), and the felt made a world of a difference. It also made a huge difference in my OSFA bluetooth speaker with the frame around it (0.5").

Bill, your thin wall cab only has about a 0.25" lip, so I feel it might be minimal, but Jim's build looks closer to a half inch, and the effect will likely not be as subtle.

Either way, felt will subdue the effects if the aesthetics are required.

[jimbones]

Warning, the lip from the top panel will cause some major diffraction.
Wolf

GAA!!! I was waiting for you to say that Lol!! So lets see what the measurements bear out I was thinking of applying this adhesive backed thick felt to make a smooth transition to minimize the effects.

[jimbones]

OK I am ready to do FRD measurements on the baffle. As I understand I am to measure each driver individually (no xo with exception of a cap on tweeter). Am I to measure drivers in pairs?? I'll measure with mic between mid and tweet 1m out.

[rpb]

OK I am ready to do FRD measurements on the baffle. As I understand I am to measure each driver individually (no xo with exception of a cap on tweeter). Am I to measure drivers in pairs?? I'll measure with mic between mid and tweet 1m out.

I do things differently than many here. What I would do first, is to measure each driver, on axis, and maybe 45 degrees off axis, and just look at the measurements. Post them so we can look too. No need to make an frd right away. Move the mic around, and just look for diffraction, or driver issues. Up, down, etc. See what range each can cover comfortably. Look for big peaks, or dips.

It may take some time for you to really get good measurements, and questions may arise about your measurement setup. Measuring the tweeter is usually easy, but the mid will require measuring lower frequencies, and that requires a decent setup to keep out the room reflections. The woofer is even harder, but I have some workarounds that I use. PCD purists may scoff at how I might arrive at a 3-way x_over. To do things my way, you would need some caps, coils, and resistors on hand. If you want to trust a sim, some of the other guys will be of more help.

[jimbones]

I do things differently than many here. What I would do first, is to measure each driver, on axis, and maybe 45 degrees off axis, and just look at the measurements. Post them so we can look too. No need to make an frd right away. Move the mic around, and just look for diffraction, or driver issues. Up, down, etc. See what range each can cover comfortably. Look for big peaks, or dips.

It may take some time for you to really get good measurements, and questions may arise about your measurement setup. Measuring the tweeter is usually easy, but the mid will require measuring lower frequencies, and that requires a decent setup to keep out the room reflections. The woofer is even harder, but I have some workarounds that I use. PCD purists may scoff at how I might arrive at a 3-way x_over. To do things my way, you would need some caps, coils, and resistors on hand. If you want to trust a sim, some of the other guys will be of more help.

Thanks Ill start with response of individual drivers.

[jimbones]

General question, is there a way to just jump to the last page of the thread rather than indexing through each page?

[Wolf]

Click the "down arrow blue blob" on the front page next to the thread you want to open, as well as having your display settings as oldest first. This will take you to the first new post since you last looked.

Wolf

[jimbones]

Click the "down arrow blue blob" on the front page next to the thread you want to open, as well as having your display settings as oldest first. This will take you to the first new post since you last looked.

Wolf

BINGO!! lol thanks

[rpb]

OK I am ready to do FRD measurements on the baffle. As I understand I am to measure each driver individually (no xo with exception of a cap on tweeter). Am I to measure drivers in pairs?? I'll measure with mic between mid and tweet 1m out.

Have you made any measurements yet?

[jimbones]

Have you made any measurements yet?

Close I had to order some wire, should be coming today. Last night I read up on Omnimic User manual so Thursday looks good for zma and frd. Thanks for your patience. Ive been doing a lot of detail work on the speaker to get it to the point I can close it up. I lined the walls with mlv and felt padding (jute) I assume I dont put any stuffing at all?