Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Multi-Way Conventional loudspeakers with crossovers

Mid and high range speakers
Mid and high range speakers
Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 23rd January 2018, 08:42 AM   #11
AllenB is offline AllenB  Australia
diyAudio Member
 
Join Date: Oct 2008
Quote:
Originally Posted by gagashagy View Post
So if understand you correct, then makes no sense to do what I had in mind.
I didn't mean that, most of us have probably done it that way before, and might again because neither way is wrong. I guess that it would seem more ordered with separate amps because it makes level matching easier. It also gives you the option to put your crossover after the amp, before it, or both. It also allows you to choose an amp that suits the bass and one that suits the treble, but that is at nitpicking level. Whatever you decide there should be experience here to help.
  Reply With Quote
Old 23rd January 2018, 09:20 AM   #12
Juhazi is offline Juhazi  Finland
diyAudio Member
 
Juhazi's Avatar
 
Join Date: Mar 2007
Location: Jyväskylä, Finland
Time to learn - useful starting points!

http://www.aes-media.org/sections/pn...sign_rev_c.pdf
Loudspeaker Design, Measurements, Theory | Audioholics
DIY Audio Articles
Speaker Building, Speaker Design, Loudspeaker Enclosure Design & Construction
__________________
AINOgradient speaker project
  Reply With Quote
Old 23rd January 2018, 11:39 AM   #13
Mrcloc is offline Mrcloc  South Africa
diyAudio Member
 
Join Date: May 2016
Location: Pretoria
I suggest the links posted, learn.

A great starting point is to just go ahead and build - get yourself some tweeters, buy a 2kHz crossover off the shelf, put everything in a 25 litre vented box (a port of 5 cm diameter by about 10 cm length should be fine). You may need a 10 ohm resistor (10W) in series with the tweeter, so try to get a crossover that has a resistor in. Bang it all together and see how it sounds. Then start refining it. Doing something helps you to understand the literature, and your only loss would most likely be (at the most) the wood and crossover.
  Reply With Quote
Old 23rd January 2018, 06:49 PM   #14
PeteMcK is offline PeteMcK
diyAudio Member
 
Join Date: Feb 2002
Location: Western Sydney
re:'this won't be needed' - I looked them up anyway :-):
Fs 60; Re 6.5; Qm 6.59; Qe .65; Sd 106; Vas 3.9
seems to model well in 10L tuned to 50Hz
__________________
Impedance varies with frequency, use impedance plots of your drivers and make crossover calculations using the actual impedance of the driver at the crossover frequency
  Reply With Quote
Old 24th January 2018, 12:44 PM   #15
Mrcloc is offline Mrcloc  South Africa
diyAudio Member
 
Join Date: May 2016
Location: Pretoria
Well, there you go. 10L does look good for these. A tool I use says a 14L box with a 41Hz vent will be quite good.

My 25L wasn't so bad after all. And the 10cm port would have tuned to about 40Hz. And I pulled these values from my thumb. There are great tools available to help you design decent enclosures and crossovers. I still say build now and refine later.

BTW, some pics of your stuff might be nice for everyone to see...
  Reply With Quote
Old 29th January 2018, 07:45 PM   #16
gagashagy is offline gagashagy
diyAudio Member
 
Join Date: Jan 2018
Quote:
Originally Posted by PeteMcK View Post
Fs 60; Re 6.5; Qm 6.59; Qe .65; Sd 106; Vas 3.9
seems to model well in 10L tuned to 50Hz
Hi, thank you very much! I am in looking these parameters up in spare time, but maybe someone could put these in more simple words?

Fs 60 - Frequency bellow which the driver should not be used (Otherwise it will selfdestruct)

Re 6.5 - DC resistance. I got 10.6 ohms on my multi-meter and somewhere saw that rule of thumb is to round the number to closest value, 8 ohm in this case?

Qm 6.59 and Qe .65 - From these I got Qts 0.592 and in multiple sources I see, that qts between .4 and .7 is suitable for sealed enclosure. I mean, a lot of you suggested vented enclosure, or sealed enclosure can be tuned as well?
Could someone please explain in somewhat simple terms, how is enclosure tuning done?

Regards
  Reply With Quote
Old 30th January 2018, 02:31 AM   #17
AllenB is offline AllenB  Australia
diyAudio Member
 
Join Date: Oct 2008
Quote:
Originally Posted by gagashagy View Post
Frequency bellow which the driver should not be used (Otherwise it will selfdestruct)
No. The output will fall below Fs. Many woofers are run full range so they receive low bass, they just don't respond to it.

Quote:
I got 10.6 ohms on my multi-meter and somewhere saw that rule of thumb is to round the number to closest value, 8 ohm in this case?
10.6 is rounded to the first decimal place. This is a useful level of rounding. Have you subtracted the meter lead resistance?

Quote:
.4 and .7 is suitable for sealed enclosure. I mean, a lot of you suggested vented enclosure,
You can put anything in a sealed box, but a low Q might give a less useful rolled off response.

If you divide the resonant frequency by the Q, you can assess motor strength and higher numbers can show suitability to vented or horn loaded enclosures.
  Reply With Quote
Old 5th February 2018, 09:45 AM   #18
gagashagy is offline gagashagy
diyAudio Member
 
Join Date: Jan 2018
Quote:
Originally Posted by AllenB View Post
You can put anything in a sealed box, but a low Q might give a less useful rolled off response.

If you divide the resonant frequency by the Q, you can assess motor strength and higher numbers can show suitability to vented or horn loaded enclosures.
I've cut out plywood pieces and now before putting all together, - am trying to figure out, what kind of tweeters to order. (Most likely this is not the best order of steps, but I had materials laying around and I was bored) My preferred design is to have small towers with ~10 L for woofer but it can be adjusted by moving the inner wall, to increase volume, therefore make the setup vented if sealed fails. (I've decided to go 'test and trial'). Then cut out the back where tweeters would be, thus having two separate compartments for each driver woofer and open back in same enclosure.
Now what I cannot quite figure out is - where to cut off the woofer. Would it make sense to make a mock-up box, put the woofer in it and see at which frequency it starts to sound bad?
Since I don't have the driver's graph and don't know where the woofer cuts off, I'm thinking about getting a pair of broadband's which goes down all the way to 80 hZ, so I'd have headroom. Then again, this idea does not work with the open back enclosure, since broadband would require sealed/vented box.

Regards
  Reply With Quote
Old 5th February 2018, 01:57 PM   #19
gagashagy is offline gagashagy
diyAudio Member
 
Join Date: Jan 2018
Additional thing that I encountered - if I would like to create 2-way crossover with frequency 100 Hz (assumption based on previous amp output for the woofer that I have) then I have to find fairly big inductor. Around 24 mH or higher. So this once again, raises question if I could reliably tell where the woofer falls in frequency without special equipment. (Fingers crossed it was just set up bellow 120 Hz and it can actually work up to 400 Hz. - this would make things easier)
  Reply With Quote
Old 7th February 2018, 01:48 AM   #20
Tweet is offline Tweet  Australia
diyAudio Member
 
Join Date: Jan 2015
A 170mm woofer would reasonably be expected to work up to 2Kc/s, so you could make your crossover that high which would generally work in with most tweeters with a low resonance of around 600 - 700 c/s. Use a LR2 crossover at 2Kc/s and pad down the tweeter to match the woofer.

Get some 'free' basic software tools to put yourself in the game of crossover design. The crossover will make or break your efforts in getting a satisfactory result.

This bit of free software will allow you to measure the impedance of your speakers and by deduction through impedance measurement ....capacitance and inductance. You will need to make up a simple jig to do so, and through the use of a sound card in your computer. It allows you to export zma files to X-Sim.
See below.....
AcustikA signal analysis software tools

There is X-Sim too, a very useful tool for fine tuning.
http://libinst.com/Xsim/XSimSetup.exe

Some chat on it..........
XSim free schematic-based crossover designer program - Techtalk Speaker Building, Audio, Video Discussion Forum.
There are many 'free' box design software out there too. Also on-line Passive Crossover Designers which will give you target values for filters rather than guessing at values.

2-Way Crossover Calculator / Designer

Hope this might help somewhat, but beware, loudspeaker design can be habit forming.

C.M

Last edited by Tweet; 7th February 2018 at 01:52 AM.
  Reply With Quote

Reply


Mid and high range speakersHide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Speakers full-range with a high resistance. Svjatoslav Full Range 67 1st June 2018 01:15 AM
High quality floor standing speakers,full range plans for diy anyone have a link? nautilusdave Full Range 34 22nd February 2017 08:06 PM
Building a high pass filter / crossover for my small full range speakers Howard Full Range 3 24th October 2013 01:15 PM
How to build simple, cheap, high WAF, full range speakers scigu63 Full Range 15 6th June 2013 02:17 AM
Power supply:Universal AC input/ Full range,High Efficiency, and High reliability hang Vendor's Bazaar 12 24th July 2009 03:46 AM


New To Site? Need Help?

All times are GMT. The time now is 02:54 PM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 14.29%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio
Wiki