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

Software Tools SPICE, PCB CAD, speaker design and measurement software, calculators

VituixCAD
VituixCAD
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 9th November 2017, 01:24 PM   #131
kimmosto is offline kimmosto  Finland
diyAudio Member
 
Join Date: Oct 2005
Location: Kuopio
Quote:
Originally Posted by DBMandrake View Post
Depending on how I measure it the acoustic offset between the drivers is between 35-50mm.
Not so moderate distance anymore. Few all-pass blocks could be rational enough if you don't modify existing enclosure and tilting causes too much trouble at top octave.
  Reply With Quote
Old 9th November 2017, 02:02 PM   #132
DBMandrake is offline DBMandrake  Scotland
diyAudio Member
 
DBMandrake's Avatar
 
Join Date: Nov 2010
Location: Glasgow, UK
Quote:
Originally Posted by kimmosto View Post
Not so moderate distance anymore. Few all-pass blocks could be rational enough if you don't modify existing enclosure and tilting causes too much trouble at top octave.
Yes it is quite an offset to deal with, tilting is not an option as the the tweeter is a 50mm tall ribbon with significant vertical directivity in the top octave, so really needs to be mounted at right angles near ear height for best results.

Other than mounting the tweeter in a set back pod or using an active crossover with digital delay, I think the all-pass filters are my next best option, and I'm interested to try them anyway as I have not used this approach before in a passive crossover. So it is an interesting experiment.

Yes it's 8 extra components for the two cascade filters needed for enough delay but the close phase tracking through the crossover region, well behaved symmetrical vertical lobe, and symmetric 4th order slopes will be worthwhile in my opinion.

All the other passive options I've SIMed so far (unequal slopes, with/without reversing driver phase etc) have all performed much worse and were serious compromises.

Also they are not large components - 0.22mH and 3.5uF are quite manageable in size even with eight of them, and as the tweeter already needs about 5dB of padding I don't need bulky very low resistance coils. I have room for a crossover board in the bottom panel of the cabinet of up to about 35cm x 28cm, so I think I will have room.
__________________
- Simon

Last edited by DBMandrake; 9th November 2017 at 02:07 PM.
  Reply With Quote
Old 22nd November 2017, 03:13 PM   #133
kimmosto is offline kimmosto  Finland
diyAudio Member
 
Join Date: Oct 2005
Location: Kuopio
Revision 1.1.16.0 (2017-11-22). See changelog.
* SPL Trace improved. Dragging of boundary lines, image renewing etc.
* Added Auxiliary calculator tool. The first version includes Time window and Wave length calculators, but some others will be added later.
  Reply With Quote
Old 22nd November 2017, 10:00 PM   #134
aczern is offline aczern
diyAudio Member
 
Join Date: May 2008
Quote:
Originally Posted by kimmosto View Post
* Added Auxiliary calculator tool. The first version includes Time window and Wave length calculators, but some others will be added later.
I suggest:
Maximum frequency for a near field measurement for the diaphragm diameter.
A time duration and a length of one or a few samples for the definite sampling frequency.
  Reply With Quote
Old 23rd November 2017, 05:48 AM   #135
kimmosto is offline kimmosto  Finland
diyAudio Member
 
Join Date: Oct 2005
Location: Kuopio
^Ok.
Max. frequency calculator and some warning could also be in Merger tool where Sd or Dd is entered and transition frequency finally selected. No problem to locate in Auxiliary calc. fNFmax=c/2/pi/r is quite simplified and rough theory but could be valuable.
  Reply With Quote
Old 24th November 2017, 11:26 AM   #136
kimmosto is offline kimmosto  Finland
diyAudio Member
 
Join Date: Oct 2005
Location: Kuopio
Quote:
Originally Posted by aczern View Post
Maximum frequency for a near field measurement for the diaphragm diameter.
A time duration and a length of one or a few samples for the definite sampling frequency.
Done in rev. 1.1.17.0
  Reply With Quote
Old 24th November 2017, 05:58 PM   #137
aczern is offline aczern
diyAudio Member
 
Join Date: May 2008
Thanks

Could you remove the upper frequency limit for SPL Trace? This tool is useful for creating files for other programs too.
  Reply With Quote
Old 25th November 2017, 01:27 PM   #138
kimmosto is offline kimmosto  Finland
diyAudio Member
 
Join Date: Oct 2005
Location: Kuopio
Quote:
Originally Posted by aczern View Post
Could you remove the upper frequency limit for SPL Trace? This tool is useful for creating files for other programs too.
It's not just a limit. Internal frequency scale (10...22k, 534 points) is global inside whole program package. Individual tool which doesn't have direct response data connection to others can be disconnected from global freq. scale by modifying some public functions. It's doable and preliminary done, but not fully tested.

Could you mention some other programs you would supply with output of SPL Trace?
  Reply With Quote
Old 25th November 2017, 01:40 PM   #139
ergo is offline ergo  Estonia
diyAudio Member
 
Join Date: Mar 2001
Location: Tallinn, Estonia
My last application for VCAD SPL trace for example was to read data from lab microphone calibration chart that came with it... data goes to 40k+ so there such feature would be useful. I then transferred it to CLIO FW as cal file eventually. I had to go through LspCAD though as CLIO accepts max 100 data lines in the file (silently ignores upper frequencies if there are more than that which is quite a bad way to implement something important like calibration).

From this a potential ask would be to also be able to say how many data points should SPL trace output... but not sure how many use cases beside the CLIO case do need that.

LspCAD would support upto data upto 50k.
__________________
Ergo
  Reply With Quote
Old 25th November 2017, 03:47 PM   #140
aczern is offline aczern
diyAudio Member
 
Join Date: May 2008
Quote:
Originally Posted by kimmosto View Post
Could you mention some other programs you would supply with output of SPL Trace?
ARTA - a microphone calibration file made from a picture
LspCAD - frequency and impedance responses from a datasheet
Xover - as above
  Reply With Quote

Reply


VituixCADHide 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


New To Site? Need Help?

All times are GMT. The time now is 11:59 PM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.79%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright ©1999-2017 diyAudio
Wiki