3 way crossover help?

Hi,
Any suggestions?
I am making a 3 way syestem with a hivi rt1c-a tweeter hivi dmn-a mid and 2 4 ohm dayton dc 160s-4 woofers in series...
I think crossing the tweeter at 600hz and the wooffers at800hz with a 24db slope on the mid. I am just working seven days a week now and need some help with a design..too much to ask?
Thnaks
B
 

BlueWizard

Member
2007-06-29 8:49 pm
I don't think it is really clear what you are trying to do. For one thing, a little punctuation might help.

How am I to interpret this? -

3 way syestem with a hivi rt1c-a tweeter hivi dmn-a mid and 2 4 ohm dayton dc 160s-4 woofers in series...

Is that -

hivi rt1c - a tweeter
hivi dmn - a mid
Two 4ohm Dayton dc160's

..but then '4 woofers in series' makes no sense. And why series, and why 4 ohm?

Next we have -

crossing the tweeter at 600hz and the woofers at 800hz with a 24db slope on the mid.

So much of that makes no sense at all. First can I assume that you are crossing from mid-to-tweeter at 6,000hz (not 600hz)?

The HiVi DMN is a soft dome fabric midrange with a frequency response of 800hz to 9,000hz. You are OK on the high end with a 6,000 crossover, but not on the low end with a 800hz crossover. You need to be well within the frequency range of the speaker, which means about a 1500 to 2000hz crossover low-to-mid.

The HiVi RT1C is a Planar Isodynamic Tweeter with at 3,000 to 21,000hz response. So you are OK for the mid-to-high crossover at 6,000hz.

The Dayton DC160 6.5" woofer is available in 8 and 4 ohms, shielded and unshielded, and has a freq response of 33hz to 4,000hz. So, I'm guessing any crossover up to 2500 (or possibly 3000hz) would be fine. So, you are safe there.

I'm guessing the reason you want 24db/octave crossovers is to make up for the limitations of the midrange, but even with that sharp slope you can't crossover right at the limit of the frequency response (800hz).

If you insist on using HiVi, then I would go with one of these Mid/Bass drivers -

HiVi B3N 3" Aluminum Driver Round Frame ($9.97)
http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=297-428

HiVi B4N 4" Aluminum Midbass Round Frame ($14.88)
http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=297-429

The only other HiVi mid/bass options that seem compatible are in the $50 to $70 range each.

There are certainly people here who are far more knowledgeable than I am on this subject, but from the components you seem to be using, I don't think it can be done as I've interpreted your statements.

I think the best you can do with the components you've selected is to move the woofer-to-mid crossover up into the 1,000hz to 2,000hz range. Which would also allow you to use 12db/octave slopes.

Anyone else have any better ideas?

Steve/bluewizard
 
Hello Blue Wizard,
You are definately right about my punctualtion and typing.
I am sorry for that.
My idea about the Dayton 4 ohm woofers in series was to make a combined load of 8 ohms and at the same time boost the sensitivity to around 93db...the same as the mid and tweeter.
I have these driver around the house so I thought I would use them. I also don't have any software to design circuts .That is why I asked for suggestions
Thanks for you help.
Bruce
 

BlueWizard

Member
2007-06-29 8:49 pm
800hz is a very typical crossover from bass-to-min IN GENERAL, but in your case it simply won't work.

If you have the speakers and insist on no modifications of substitutions, then you simply need to move your crossovers up to about 1200hz to 1800hz with 1600hz being ideal.

If you really don't have software to design the crossovers, you can search the internet for free crossover design software. I'm sure others here can recommend both crossover software and full speaker modeling, testing, and design software; all free.

Here are a few I have collected-

FDR Consortium-
http://www.rjbaudio.com/Audiofiles/FRDtools.html

Speaker Workshop-
http://www.speakerworkshop.com/

Linear Team WinISD (very popular) and WinISD Pro-
http://www.linearteam.dk/default.aspx?pageid=winisd

Jeff Bagby's Loudspeaker Design Software including Crossover Design-
http://audio.claub.net/software/jbagby.html

Speaker Calculator -
http://www.mhsoft.nl/SpeakerCalculator/

There is another really good one that is a combination of 3 or 4 programs but I can't find the link to it even though I've downloaded the software. Can anyone else help with this one?

Ahh... I found it on my computer, it is ARTA, search google and you should find it.

There is also -

Basta
Edge
BoxCircuit3
PassiveCrossoverDesign6.12
ResponseModeler2
WooferBoxandCircuitDesigner
Etc...

If that is too time consuming then simply buy ready made crossovers. In you case you will need two per speaker; one to crossover the lows and another to crossover the highs.

Here is a sample, although they don't have specifical what you need, it should give you some idea.

Part Express-
http://www.partsexpress.com/webpage.cfm?webpage_id=3&CAT_ID=48&ObjectGroup_ID=193

Other sources are-

Madisound-
http://www.madisound.com/index.html

MCM Electronics-
http://mcmelectronics.com/

Anyone have any other ideas?

Steve/bluewizard