first total crossover...advice...dayton 7" alu. and hi-vi k1

[nerd of nerds]

hello fellow diy speaker fanatics!

well, i finally decided that it was go time for this project...

The goal? a good, budget, diy loudspeaker with a crossover i designed myself (or if someone is feeling generous, designed by someone else...)

I think the dayton 7" are great candidates for this project for several reasons:
1: cost, they are cheap
2: They perform well as zaphs graphs (that rhymes...) depict
3: i prefer aluminum woofers
4: They are dead sexy!


I think that i should get some ok bass out of these becuase of room gain and such...i DO plan on adding a sub later on but for now i'd like these to go fairly low and get ok output...

My question is this: I'm planning on crossing over at around 1800 to 2100hz, what order crossover should i use?

What other things will i need to incorperate into the crossover for this to work well?

Should i go ported for good bass or sealed?

I have never designed or built a crossover before and would like to keep this somewhat minimalistic (without building a crap speaker that is...) so i don't have too much i can bugger...

[nerd of nerds]

forgot to mention...

i know the tweeter will probobly have to be padded down a bit to blend well with the woofers...


I'm thinking of making it either a largish bookshelf tm or a floorstanding tmm or floorstanding mtm...

decisions decisions

[morbo]

If you are referring to the normal Dayton aluminum 7" drivers, rather than the RS 7"ers, have you looked at the Vifa/Dayton aluminum kit that PE sells? Seems like the simplest solution.

**edit*** sorry, I'm stupid and missed the K1 tweeter requirement.

[chainenoble]

i think your crossing that tweeter too low.also it has a low power rating witch could damage it if you cross to low

[nerd of nerds]

Originally posted by chainenoble
i think your crossing that tweeter too low.also it has a low power rating witch could damage it if you cross to low

That is the tweeter that zaph himself recomended to me a while back...but if you know of another tweeter that would work well in that crossover range that is around or less than 30 bucks then by all means tell me...

The reason i don't wanna go using exotic, expensive, super nice tweeters (this is already a very good woofer...) for this project is that it is a lot easier to kill a tweeter than it is a woofer...

This will be my first project with a self designed crossover...i'm already pretty good at building the boxes, so that isn't an issue at all...

And as for the kit...no

I really don't like the idea of a kit...i like building my own boxes and i don't want to have some crappy predesigned crossover...

[RJ]

I have used the 7" Aluminum in quite a few projects and I've always mated them with the PT2 Planars. In your case I would try the Seas H1212.
http://www.madisound.com/cgi-bin/ind....7743&pid=1005

I've crossed it as low as 1450 but I'm now crossing it at 1750 with 2 MCM Aluminum midbass drivers.
I've had really good results using Jon Marsh's Cauer Ellyptic crossover design.
Jon's web site;
http://www.htguide.com/forum/forumdisplay.php4?f=6

I've been using LspCad 6 demo version to design them;
http://www.ijdata.com/l_demo.htm




Good Luck on yours,Rudy

[Landroval]

RJ, what's that alu bass driver in the 3-way design? Lookswise it would go well with the Aura 3" and 4" widebands.

[nerd of nerds]

Originally posted by Landroval
RJ, what's that alu bass driver in the 3-way design? Lookswise it would go well with the Aura 3" and 4" widebands.

if i'm correct that is a 6.5" aluminum driver from mcm electronics.

Someone should order one and send it away to zaph for some testing



When are you bringing those tweeters in? And do you have any measurements to go with those?

Thanks!

[RJ]

Mark K has tested the Seas 27 TBFC/G (H1212);
http://206.13.113.199/ncdiyaudio/mar...eas_27tbfc.htm

The Midbass units in the first MTM are;
5" MCM - 55-1870
6.5 " MCM 55-2311
http://mcminone.com/
Unfortunatley, they're out of stock right now of the 6.5's.

I haven't done a frequency sweep yet, because they're just starting to break in.
I might do it today and also write down what I used for a crossover.
I've tweaked it a couple of times since.

Funny, looking at that pic it somewhat resembles a snowman.

[nerd of nerds]

i'm VERY interested to see some measurements of those 6.5" drivers from mcm...i've always loved the look of drivers without the dustcap...concave or whatever...

Well, looking at the k1 i think it suites this project just fine. Later on i'm gonna build some uber speakers with the rs180 and the seas 27tdfc in a proac esque enclosure...

now i need to start looking at what kind of enclosure to build...I've heard people talking about using the golden ratio to figure box size...are they talking about PHI?

http://www.troelsgravesen.dk/TJL_2W.htm

I REALLY like the look of that speaker...there is just something very simplistic about it that makes it beutiful...

I'd really like to build my enclosures as similar to those as possible (while still tuning them for the drivers i'm using...). Would it be okay if i just copied these? I was plaing around in winisd a while back experimenting with the dayton 7" aluminums (NOT the reference series) and it looked like i could get it tuned almost flat to about 30hz...seems pretty good...

Ok, so, once i choose my crossover point and get all that calculated and get the tweeter padded down enough for the woofer, what else do i need? Baffle step compensation? I plan on Flush mounting the tweeter in the upper (inner) corners of the speakers and centering the woofers just below them.



I plan on building the enclosures out of MDF in a few weeks so that i can get the drivers (the woofers at least) mounted and measured.

Wheew, i think thats about it for now...