Need help with Modeling Software - 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 12th November 2003, 09:51 PM   #1
Wright is offline Wright  United States
diyAudio Member
 
Join Date: Apr 2003
Location: Seattle, WA
Send a message via AIM to Wright Send a message via MSN to Wright
Question Need help with Modeling Software

Hey Guys,

I have been trying to model up a subwoofer for my friend using the Tangband 8" W8-740c. The parameters for this woofer can be found here and here. We decided to use the plate amp from Partsexpress
here. We are looking to do a vented design with a long port to save money over pr's. I have tried to model the sub in "subwoofer simulater" and "winisd" but I'm not having much luck. I think I have all of the parameters entered in correctly but I wasn't sure about the "PE", "Z", or "dia". Is that the diameter of the voice coil or of the cone? Also for Le does the software want it at 1khz or 20 khz?
My goal in using these programs was to determine necessary box size and port length, and hopefully get an idea about how low it will go and how flat it will be. I was also confused with winisd about the power tab. I entered in 100 watts as opposed to 1 watt and the spl graph went off the chart, is that supposed to happen?
I appreciate the help, hopefully I can get up to speed with these programs.

George
  Reply With Quote
Old 12th November 2003, 11:06 PM   #2
Ron E is online now Ron E  United States
diyAudio Member
 
Ron E's Avatar
 
Join Date: Jun 2002
Location: USA, MN
Probably not a good idea to use that sub without a PR.

LE won't matter much so it doesn't matter what you enter.

To get a response shape that works OK with that bass amp - it has ~6dB boost at 30Hz - I tried a 12 liter box tuned to 28Hz with a 2" diameter by 24" long port. Port velocity reaches 40+m/s, which is high and you will likely have noise, even if flared. Using a 3" port 55" long, your port velocity goes down to 17m/s, which is better, but the port is ridiculously long...

Tuning small boxes to low frequencies is a job for a passive radiator.
__________________
Our species needs, and deserves, a citizenry with minds wide awake and a basic understanding of how the world works. --Carl Sagan
Armaments, universal debt, and planned obsolescence--those are the three pillars of Western prosperity. —Aldous Huxley
  Reply With Quote
Old 12th November 2003, 11:13 PM   #3
tg3 is offline tg3  United States
diyAudio Member
 
tg3's Avatar
 
Join Date: Nov 2002
Location: Seattle, WA
No experience with above programs.

But have you tried UniBox from the FRD Consortium? Very easy to use.

And I'm always amazed at the number of Seattlites on the audio forums...
__________________
Folly befits a fool.
  Reply With Quote
Old 12th November 2003, 11:32 PM   #4
Ap is offline Ap
diyAudio Member
 
Ap's Avatar
 
Join Date: May 2002
Location: Sydney, Australia
The only parametes you need to model sub volume
are qts, fs, vas.

For tuning & vent velocity you will need power (pe) & Qes.

I get 10litres tuned to 40hz using winisd with a port 2 x 13"yields flattest response

This driver is very inefficient at 84db & low Re so will require high power & stable amp.

The parts express one looks up to the taks but hard to comment unless tested.
  Reply With Quote
Old 12th November 2003, 11:41 PM   #5
Wizard of Kelts
diyAudio Moderator
 
Join Date: Sep 2001
Location: Connecticut, The Nutmeg State
Default Re: Need help with Modeling Software

Quote:
Originally posted by Wright
Hey Guys,

I have tried to model the sub in "subwoofer simulater" and "winisd" but I'm not having much luck. I think I have all of the parameters entered in correctly but I wasn't sure about the "PE", "Z", or "dia". Is that the diameter of the voice coil or of the cone? Also for Le does the software want it at 1khz or 20 khz?

George
Since I haven't modeled the TangBand, I cannot comment on the advisability of using a port or Drone Cone, (the original term for Passive Radiator, coined by it's inventor, Harry Olson), but I can give you the terms.

Pe = Max Continuous Power, (not instant peak power).

Z = Nominal impedance. Generally either 4 ohms, 8 ohms, or nowadays, even 6 ohms. Never 4.7 ohms or 6.8 ohms or whatever. It is the ohmage the manufacturer gives to fit into the 4 ohm/8ohm mold.

dia = The diameter of the circular frame around the cone. A speaker with a 10 inch circular frame and a 8˝" cone will be called a 10 incher. It corresponds to the popular 15", 12", 10", 8", and 6˝" that everyone uses anyway.

The actual cone itself is generally given as "Sd", and that is the area of the cone surface itself. It is a different number entirely from "dia".

Le is generally given as the Le at 1,000 Hz.
__________________
"A friend will help you move. A really good friend will help you move a body."
-Anonymous
  Reply With Quote
Old 13th November 2003, 01:29 AM   #6
Ron E is online now Ron E  United States
diyAudio Member
 
Ron E's Avatar
 
Join Date: Jun 2002
Location: USA, MN
Applying boost below the tuning frequency is a no-no Tuning to 40 Hz, no matter how flat it might appear in a simulator that doesn't account for amplifier response, is likely to cause overexcursion below resonance. A 2" port in a 10L box would have a velocity of ~47m/s when tuned to 40Hz, with ~35V input. Pretty cool if you want port noise and be able to blow out candles at 30 paces.

Without a PR, I'd probably use a small ~5-7L sealed box.

It'd make a nice (small) car woofer. There are better choices for use with a plate amp in a home.
__________________
Our species needs, and deserves, a citizenry with minds wide awake and a basic understanding of how the world works. --Carl Sagan
Armaments, universal debt, and planned obsolescence--those are the three pillars of Western prosperity. —Aldous Huxley
  Reply With Quote
Old 13th November 2003, 10:10 AM   #7
Wright is offline Wright  United States
diyAudio Member
 
Join Date: Apr 2003
Location: Seattle, WA
Send a message via AIM to Wright Send a message via MSN to Wright
Default Thanks!

Wow thanks for all the helpful replies! It is good to know what those t/s parameters mean. I wasn't having much luck with the other two programs, but I did try unibox, and found it to be more user friendly. I enjoyed entering some values and seeing it calculate the rest of them right on the money! (I am easily amused). The only thing I'm not fond of is that I can't figure out how to enter my own port length; seems the program does that for me?
Anyway about the subwoofer: I was talking to Al (RAW) before and he also encouraged me to use a passive radiator/drone clone, but since they run $50 for the high excursion version it is over our budget. He made it sound like I could go ported if I was desperate but perhaps it's a bad idea. Considering our target price range of $30-$50 for the driver, do you guys have any other driver suggestions that I could run in a ported box? The application is computer system/HT use to be coupled with a pair of SuperElf's and a pair of Elf1.0's in the rear. I would love to try and get down into the lower 30's (frequency, not price) if possible, but that might be asking to much of a small driver. Amp is as stated above, unless you have other suggestions at or below that price point. I really appreciate your suggestions, and I'm sure my buddy does too.

George
  Reply With Quote
Old 13th November 2003, 01:53 PM   #8
Wizard of Kelts
diyAudio Moderator
 
Join Date: Sep 2001
Location: Connecticut, The Nutmeg State
How about a Peerless CC 260, or 831727 in a 28 liter, (1 cu ft) box, tuned to 30 Hz?

The box is only a little bigger than your planned box, the 10 inch has a pretty long throw. I will explain later, but it has a symmetrical magnetic system that in a ported box, will give much less distortion than a non-symmetrical system-and the TangBand does not mention a symmetrical system, which means it probably does not have one.

The Peerless is more efficient.

The simulation is by Subwoofer Simulator, written by our own F4ier.

The lower line is the response not counting the room, like most modeling programs do it.

The upper line includes standard room response-actual room response may vary.

The room response was an option added by our own member, Serow.

As you can see, at 30 Hz, even without room response, you are down to around 80 dB.

With room response, you are up to around 86 dB-more efficient than your TangBand even in the midband!

Price isn't much more than the TangBand.
http://www.partsexpress.com/pe/pshow...=297-616&DID=7

You can always make the box bigger if you want, for even better response.

To tune it so low, you might get some port noise, but not too outrageous. This is a computer system, right? And a slight increase in box size leads to less port noise, if you want to get bigger.

Nice deal, I think.
Attached Images
File Type: gif peerless cc 260 1 cu ft.gif (27.7 KB, 316 views)
__________________
"A friend will help you move. A really good friend will help you move a body."
-Anonymous
  Reply With Quote
Old 13th November 2003, 02:32 PM   #9
f4ier is offline f4ier  Australia
diyAudio Member
 
f4ier's Avatar
 
Join Date: Sep 2001
Location: Sydney
Quote:
The room response was an option added by our own member, Serow.
Hi kelticwizard, once again thanks for the vote of confidence on SubSim, but what did you mean by this? Room response plotting has always been a feature of Subwoofer Simulator from day one


Wright, with which part of SubSim did you have trouble while designing your sub? It would help me improve the user interface of SubSim if you could be more specific. I know a number of SubSim users find the interface to be odd at first. While they email me for feature suggestions, no one really comments on the user-interface


Cheers,

Isaac
Attached Images
File Type: png in-room.png (17.9 KB, 295 views)
__________________
Crossover/Subwoofer Simulator
  Reply With Quote
Old 14th November 2003, 12:14 AM   #10
diyAudio Member
 
mikee12345's Avatar
 
Join Date: Nov 2002
Location: NZ
f4ier=

i think that, that member,,just submitted a room gain graph for people to use,thats all\

the user interface is alternative

i like 3db scales with lines going across,it ran slowly on my old stuffed 133mhz so i stayed with winisd.

  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
Acoustic Modeling Software HK26147 Multi-Way 0 24th November 2008 11:53 AM
I need 3D CAD Cabinet ONLY Modeling Software sdep777 Multi-Way 5 18th November 2008 09:08 PM
HELP with Box Modeling Software 69stingray Multi-Way 5 1st January 2006 04:40 PM
Crossover modeling software idea BAM Multi-Way 0 6th September 2004 09:59 PM
Speaker modeling software ogp Multi-Way 5 26th September 2001 07:36 PM


New To Site? Need Help?

All times are GMT. The time now is 06:40 PM.


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