Monster Massive - Page 7 - 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 November 2013, 07:53 AM   #61
Juhazi is offline Juhazi  Finland
diyAudio Member
 
Juhazi's Avatar
 
Join Date: Mar 2007
Location: Jyväskylä
A synergy horn with open mids will not radiate like true dipole. A dipole has same kind of radiation pattern front and back and at (nearly) same level. I think that a horn with open mids could act like supercardioid.

Anyway this backside radiation makes lots of frontwall reflections and boosts power response. How it sounds depends on speaker location, it can be for good or bad!.
__________________
AES Associate Member / My DIY speaker history: -74 Philips 3-way, -82 Hifi 85B, -07 Zaph L18, XLS10+PR/Hypex, -08 CSS125FR, -08 Hifitalo AW-7, -08 TangBand FR, -09 MarkK ER18DXT, -13 PPSL470, -13 AINOgradient
  Reply With Quote
Old 23rd November 2013, 04:33 AM   #62
diyAudio Member
 
Patrick Bateman's Avatar
 
Join Date: Oct 2006
Location: San Diego
Quote:
Originally Posted by Patrick Bateman View Post
Yeah I think that's probably the wisest route.
The LeCleach has some decent looking impulse response, but the polars are dreadful. This is mostly due to my crummy horn construction, and the fact that the midranges holes are 'tapped in' at a section of the horn where the area isn't very high at all.

Right now what I'm trying to figure out what type of directivity I want.

I used open back midranges on this Synergy horn mostly because I wanted to minimize the 'giant headphones' effect.

But it's not as simple as running them dipole; I also have to consider that dipole radiation requires different crossover points and requires different EQ than monopole does.

So before making any sawdust, I need to figure that out.
Tonight I ran some sims on various combinations of crossover point and woofers.
Basically trying to figure out if I should use one woofer or two, and what the crossover point should be.

Here's some examples:

Click the image to open in full size.
^^ Here's a sim with one waveguide, one woofer, first order xover, and a xover frequency of 1120hz

Click the image to open in full size.
^^ Here's a sim with one waveguide, two woofers, first order xover, and a xover frequency of 1120hz

Click the image to open in full size.
^^ Here's a sim with one waveguide, one woofer, first order xover, and a xover frequency of 560hz

Click the image to open in full size.
^^ Here's a sim with one waveguide, two woofers, first order xover, and a xover frequency of 560hz

Click the image to open in full size.
^^ Here's a sim with one waveguide, one woofer, first order xover, and a xover frequency of 280hz

Click the image to open in full size.
^^ Here's a sim with one waveguide, one woofer, first order xover, and a xover frequency of 280hz

Some observations:

1) All of the horizontal polars basically look the same, because going from one woofer to two doesn't impact the horizontal response much. Most of the change is seen in the vertical polars.

2) A crossover point of 1120hz sounds a little high for a Synergy horn. But due to the low order slopes, the woofers on the Synergy horn are only down 15dB at 280hz with a 1st order xover at 1120hz.

3) The polars of the 280hz xover look the best, but I'm not sure if the Dayton mids can handle that. With a 280hz 1st order xover the Daytons will only be 15dB down at 70hz and 21dB down at 35hz. Not sure if they can do that. If I *do* go that route, some serious EQ will be required.
  Reply With Quote
Old 23rd November 2013, 08:15 PM   #63
diyAudio Member
 
Patrick Bateman's Avatar
 
Join Date: Oct 2006
Location: San Diego
Click the image to open in full size.

Here's the old design for Monster Massive. I've moved away from these plans for the following reasons:
1) LeCleach sounds really nice, but there is a massive dip in the response due to reflections off the midrange taps. I think that the confined space at the throat exacerbates this. If you look at a Danley Synergy horn, you'll notice that the first few inches expands much faster, due to the walls having flat sides. So there's simply more area by the time we reach the midrange taps, and I think that reduces the effect of the taps.

2) With the LeCleach the frequencies below 1khz sounded a bit 'off' and I think this is due to the quickly broadening directivity. Above 1khz it sounded great, but I think if you want to run a LeCleach down to 250hz you'll need a bigger horn. (IE, the flare rate may be 250hz, but the directivity of my horn was only good to about 1khz. So there's a two octave range where the directivity is basically omnipolar.)

Click the image to open in full size.

Here's the new design. It features:

1) A two way synergy horn on top, using the QSC waveguide sold by Parts Express, which measures 36cm x 25cm. That should give me directivity control down to about 1100hz.
2) The woofer below the QSC waveguide is a TC Sounds 15. I'm going to run this as a dipole.
3) The midranges will be four Dayton ND91s.

I'm hoping for crossover points like this:
tweeter : 1200hz - 20khz (4 octaves)
midrange : 300hz - 1200hz (2 octaves)
woofers : 100hz - 300hz (1.5 octaves)

I'm not 100% sure on what the slopes yet.
First order slopes have the least phase distortion.
Having said that, I've read that there's a way to do 2nd order crossovers and keep everything in phase by putting a narrow bandwidth midrange between the tweeter and the woofer.

Can't find the article ATM, but John Kreskovsky from musicanddesign.com wrote an article on something like this for Speaker Builder about a decade ago.

Click the image to open in full size.
Click the image to open in full size.

Monster Massive I was inspired by the Jadis Eurythmie; Monster Massive II was inspired by the Gradient Helsinki. I basically showed my girlfriend and her daughter as series of loudspeakers and asked them which one they could live with.
  Reply With Quote
Old 23rd November 2013, 08:50 PM   #64
tinitus is offline tinitus  Europe
diyAudio Moderator R.I.P.
 
Join Date: Nov 2005
Quote:
Originally Posted by Patrick Bateman View Post
.... a narrow bandwidth midrange between the tweeter and the woofer.[/b]

Can't find the article ATM, but John Kreskovsky from musicanddesign.com wrote an article on something like this for Speaker Builder about a decade ago.
cue-word ... B&O filler driver

Duelund and Beyond

is that the article ?
__________________
sometimes we know very little, and sometimes we know too much
  Reply With Quote
Old 4th December 2013, 07:14 AM   #65
diyAudio Member
 
Patrick Bateman's Avatar
 
Join Date: Oct 2006
Location: San Diego
I think so, thank you!
  Reply With Quote
Old 4th December 2013, 07:16 AM   #66
diyAudio Member
 
Patrick Bateman's Avatar
 
Join Date: Oct 2006
Location: San Diego
Click the image to open in full size.

Click the image to open in full size.

Here's some pics of the horn coming together.
Waveguide is the ubiquitous QSC PL-000446GP.
Tweeter is the Celestion CDX1-1425. (Mine are rebadged by QSC.)
Midrange is the ND91.
Woofer will likely be a TC Sounds 15.

Click the image to open in full size.
Midrange ports are long and skinny, similar to some of the Yorkville and Danley Synergy horns.
  Reply With Quote
Old 4th December 2013, 10:43 AM   #67
diyAudio Member
 
Join Date: Apr 2010
Is this a QSC 152 WG?
  Reply With Quote
Old 4th December 2013, 03:42 PM   #68
diyAudio Member
 
Patrick Bateman's Avatar
 
Join Date: Oct 2006
Location: San Diego
Quote:
Originally Posted by chrapladm View Post
Is this a QSC 152 WG?
QSC PL-000446GP
  Reply With Quote
Old 4th December 2013, 04:14 PM   #69
diyAudio Member
 
Join Date: Jan 2008
Quote:
Originally Posted by Patrick Bateman View Post
1) LeCleach sounds really nice, but there is a massive dip in the response due to reflections off the midrange taps. I think that the confined space at the throat exacerbates this.

Here's the new design. It features:

I'm hoping for crossover points like this:
tweeter : 1200hz - 20khz (4 octaves)
midrange : 300hz - 1200hz (2 octaves)
woofers : 100hz - 300hz (1.5 octaves)

I'm not 100% sure on what the slopes yet.
First order slopes have the least phase distortion.
Patrick,

1) Did you ever try shorting the midrange drivers out when testing the HF to see if they were acting as a resonant trap, rather than the tap hole reflections being the cause of the massive midrange dip?

2) The acoustical crossover slope will never be "first order" in a Synergy design regardless of the electrical filters used.
What do you mean by "phase distortion"?

Art
  Reply With Quote
Old 4th December 2013, 05:02 PM   #70
diyAudio Member
 
Patrick Bateman's Avatar
 
Join Date: Oct 2006
Location: San Diego
Quote:
Originally Posted by weltersys View Post
Patrick,

1) Did you ever try shorting the midrange drivers out when testing the HF to see if they were acting as a resonant trap, rather than the tap hole reflections being the cause of the massive midrange dip?

2) The acoustical crossover slope will never be "first order" in a Synergy design regardless of the electrical filters used.
What do you mean by "phase distortion"?

Art
While the dip at 1200hz was a bummer, there was a bigger problem with my LeCleach horn.

Here's what I think is going on:

Click the image to open in full size.
On the left is my LeCleach horn, with a mouth that follows the golden ratio. Cutoff is something like 350hz
Click the image to open in full size.
Here's a similar horn made by someone in Sweden named 'Asto' in wood. (From Astos biradial lecleach wooden horns )

Click the image to open in full size.
Click the image to open in full size.

Here's the polar response of our two horns. See how my horn isn't very consistent, and my horn is rolling off the highs?

I think a great deal of this is due to my crummy craftsmanship. The rough and inconsistent shape and surface of the horn is hurting the consistency of the polar response and it's rolling off the highs. At 10khz my horn has lost 10dB of output, Asto's has lost none. (Ignore the green curve, that's the QSC waveguide which I was comparing the LeCleach to.)

Click the image to open in full size.
Here's the response with the crossover; basically I'm TRYING to flatten it out electrically, but failing, because the problem isn't electrical it's physical

Click the image to open in full size.
Here's the QSC with crossover, which is much more consistent



Bottom line - my fiberglass LeCleach horn is pretty hopeless. There's a reason that people pay $500 a pair for horns from Autotech


I'll admit that the dip in the midrange from the taps is probably not the end of the world, but that polar response is un-fixable

Last edited by Patrick Bateman; 4th December 2013 at 05:25 PM.
  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
Massive P3000.1 massive DC offset amc32 Car Audio 5 16th March 2011 05:40 PM
MASSIVE heatsinkS Krisfr Swap Meet 5 17th September 2010 05:59 AM
Massive D400x SS64 Car Audio 33 7th January 2010 02:11 AM
"Monster" Cable vs Monster Vintage MonsterVintage Everything Else 0 18th October 2004 11:35 PM


New To Site? Need Help?

All times are GMT. The time now is 06:42 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