Before I start out, I need some direction - diyAudio
Go Back   Home > Forums > Loudspeakers > Multi-Way

Multi-Way Conventional loudspeakers with crossovers

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 17th June 2007, 11:46 PM   #1
diyAudio Member
 
Join Date: Sep 2005
Default Before I start out, I need some direction

I need some advice so that I know which direction to take with my project (my first).

1. CAE software: I know, I guess this has been up many, many times but my searches came up with nothing about SPEAK. The only alternative that is reasonably cheap that can handle 5 drivers on the baffle is SPEAK, as far as I know. I don't know about lspCAD Stnd, but lspCAD Stnd seems to be too limited in features. Anyone who has used SPEAK? Is it any good? What about support, I sent an enquiring e-mail some weeks ago, still no reply? Speaker Workshop is not an option. Maybe I want too much?

2. What is the easiest to implement, a three-way speaker or a two-box solution with a sub unit that has a two-way on top of it? I was thinking the two-box, then it will be easier to do changes/upgrades in the future?

My plan is using four, or maybe two 10" or 9" woofers in isobaric configuration coupled in push/pull. Any reason to have one vs. two chambers in the sub-box?

3. Can I concentrate on the sub-box and leave the two-way for later?

4. I have considered the following woofers:
Dayton RSS265HF-4
Scan-Speak 23W/4557T00 9"
SEAS Excel W26FX001 E0026
SEAS Prestige L26RFX/P H1209
because: Fs lower than 25 Hz, no PP-cone, no foam surround, EBP not much higher than 50.

5. The room is 30-35 m^2 and 2.26 m high, and opens up to an additional 10 m^2.

6. The test box, what is mandatory of a test box, that is, how close to the final box does it have to be? Which factors are of importance?
  Reply With Quote
Old 18th June 2007, 04:19 AM   #2
frugal-phile(tm)
diyAudio Moderator
 
planet10's Avatar
 
Join Date: Oct 2001
Location: Victoria, BC, NA, Sol III
Blog Entries: 5
Default Re: Before I start out, I need some direction

Quote:
Originally posted by buggsson
2. What is the easiest to implement, a three-way speaker or a two-box solution with a sub unit that has a two-way on top of it? I was thinking the two-box, then it will be easier to do changes/upgrades in the future?
2 way with a sub is easier i'd say. Even easier is a 1 way with active sub.

dave
__________________
community sites t-linespeakers.org, frugal-horn.com, frugal-phile.com ........ commercial site planet10-HiFi
p10-hifi forum here at diyA
  Reply With Quote
Old 18th June 2007, 08:41 AM   #3
maxro is online now maxro  Canada
diyAudio Member
 
maxro's Avatar
 
Join Date: Dec 2004
Location: Survey says: Least happiest city in Canada
Er, Planet10, perhaps you could move this into the general loudspeaker forum and out of the fullrange section. I suspect more replies will come of it.
__________________
"No one likes jazz that much; even the guy playing it had to take drugs." -Bart Simpson
  Reply With Quote
Old 18th June 2007, 07:15 PM   #4
frugal-phile(tm)
diyAudio Moderator
 
planet10's Avatar
 
Join Date: Oct 2001
Location: Victoria, BC, NA, Sol III
Blog Entries: 5
Quote:
Originally posted by maxro
Er, Planet10, perhaps you could move this into the general loudspeaker forum and out of the fullrange section. I suspect more replies will come of it.
Good idea... done

dave
__________________
community sites t-linespeakers.org, frugal-horn.com, frugal-phile.com ........ commercial site planet10-HiFi
p10-hifi forum here at diyA
  Reply With Quote
Old 19th June 2007, 10:17 AM   #5
sreten is offline sreten  United Kingdom
diyAudio Member
 
Join Date: Nov 2003
Location: Brighton UK
Hi,

In a 2 way + sub all BSC correction is done in the 2-way.

In a 3 way the options for BSC implementation are numerous, most
of these options are not understood (e.g. partial BSC in the mid
driver + some back up from the bass unit), depends on the drivers
used and are impossible to design without decent simulation before
the drivers are chosen (IMO).

/sreten.
  Reply With Quote
Old 21st June 2007, 02:39 AM   #6
diyAudio Member
 
Join Date: Sep 2005
So I guess that I will stick with a sub + a two-way system.

For the sub section, any advantage/disadvantage to have one large chamber for all four drivers, or two chambers for each pair? (If I will need all four drivers for desired response, output etc)

I really would like some input about CAE software an in 1. Especially if anyone have had experience with SPEAK. Sure, I can use it in demo mode, but I would like some input from someone knowledgable that has had experience with it. Now that I have decided on the major design of my project, I need to decide on which software to use, so that I can start some simulations to pick the drivers.

For now, I plan to go active all the way.

I have started to collect info about what other DIY folks say are nice tweeters and midwoofers. What are you to look for when matching a tweeter to a midwoofer, more than that they have some overlapping frequency responses?

sreten,
what is BSC standing for? Audio lingo can be hard as it is, abbrivations even harder..........
  Reply With Quote
Old 21st June 2007, 07:42 AM   #7
frugal-phile(tm)
diyAudio Moderator
 
planet10's Avatar
 
Join Date: Oct 2001
Location: Victoria, BC, NA, Sol III
Blog Entries: 5
Quote:
Originally posted by buggsson
For the sub section, any advantage/disadvantage to have one large chamber for all four drivers, or two chambers for each pair? (If I will need all four drivers for desired response, output etc)
Build 2 push-push subs. Stereo woofers have big advantages over a single woofer. And push-push is even more advantageous.

Quote:
really would like some input about CAE software an in 1. Especially if anyone have had experience with SPEAK.
I can't recall ever running into anyone using SPEAK... the high price is a deterent for most diyers.

Quote:
what is BSC standing for?
Baffle Step Compensation

http://www.t-linespeakers.org/tech/b...intro-bds.html

dave
__________________
community sites t-linespeakers.org, frugal-horn.com, frugal-phile.com ........ commercial site planet10-HiFi
p10-hifi forum here at diyA
  Reply With Quote
Old 21st June 2007, 02:13 PM   #8
sreten is offline sreten  United Kingdom
diyAudio Member
 
Join Date: Nov 2003
Location: Brighton UK
Hi,

Attached are basic sims of two Daytons in a box.

Due to your driver selection criteria vent tuning frequency is low.

If the boxes are too big you could consider one driver with 1 or
2 passive radiators per box. Note that a mono sub amp driving
two seperate boxes gives better room drive than one box.
Its very arguable about having "stereo" low bass.

Personally I'd go sealed two box push push with those sort of drivers.
Sub amplifier with adjustable low bass boost would be a good idea.

sreten.
Attached Images
File Type: jpg guff.jpg (95.7 KB, 996 views)
  Reply With Quote
Old 22nd June 2007, 02:57 AM   #9
diyAudio Member
 
Join Date: Sep 2005
I don't know if I wasn't clear enough initially, but my plan was/is to build two sealed subs, isobaric and coupled in push/pull, using either two or four drivers per sub.

I am mearly brainstorming at the moment and the knowledge is scarce, so my view was that going with the rather smallish 9" or 10" drivers, I might be able to get a desired SPL or whatever, using four drivers rather than two per sub. I really do not know what I need in my room, I just felt that I had to start somewhere.

Would four drivers per sub be overkill?

Regarding SPEAK, as far as cost is a consideration, it is, but it is the least expensive software I have encounterd that can handle 5 drivers on the baffle, which is where I want to go, eventually.

I have read the link about BSC and it was interesting reading, but digesting it will be a while. I'll learn as I go along.

Box size is certainly an issue, so they cannot be to large, the dreadful WAF is a powerful force, and I am surprised that I got the OK for this project. My former speakers was a pair of Totem "Sttaf" and they were rather large, I was told. I would guess 50-60 litres for the subs would max it.

sreten, thanks for the graph. Is the different Qtc values due to varying box volumes? Is the responses to strive for, similar to the green response? Name of the software?

After all this time, it feels like I have finally begun. Software next so that I can mess around myself a bit.

What determines how low your speakers will go? I mean, I have a couple of 12" drivers I've been looking at, but they do not have much different Fs values, all else the same, would they by any reason what so ever, go lower than the 9" and 10"? If not, the smaller drivers will give a smaller box, and therefore higher WAF.
  Reply With Quote
Old 25th June 2007, 09:27 AM   #10
sreten is offline sreten  United Kingdom
diyAudio Member
 
Join Date: Nov 2003
Location: Brighton UK
Hi,

Going isobaric halves box volumes and doubles amplifier power and driver costs.
Basically will not do anything for bass extension or maximum levels.
Given the sort of drivers your considering, isobaric is not a good idea.

Push Push in force cancelling mode is your best bet, 50 to 60L per pair.

Qtc depends on box volume and stuffing, target 0.6 to 0.7 IMO.

Green is not the target, red is better but these are vented, not sealed.

Basically the bigger drivers in bigger boxes will go louder, with similar
parameters the smaller will go as low in smaller boxes but with lower
efficiency.

Sub amplifier with adjustable low bass boost would be a good idea.
This will determine "how low they go".

Try Win ISD PRo or some other sub simulator.

/sreten.
  Reply With Quote

Reply


Hide 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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
...sound direction? rinx Multi-Way 1 11th September 2008 12:50 PM
Point me in the right direction subwoffers Multi-Way 36 21st November 2007 07:42 PM
can someone look at this and point me in the right direction? thermonuclear Chip Amps 1 30th August 2005 02:36 AM
Sub Amp..in need of direction sickss Solid State 2 16th February 2005 04:01 PM


New To Site? Need Help?

All times are GMT. The time now is 02:05 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2