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

silk purse from sows ear contest?
silk purse from sows ear contest?
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 25th September 2018, 02:07 PM   #251
DonVK is offline DonVK  Canada
diyAudio Member
 
DonVK's Avatar
 
Join Date: Jan 2017
Location: Ottawa
I preferred the 2way BR with electrical XO. BTW thanks @drewmc for the improvement suggestions on the BP6 version.

Both designs work and are very listenable, and surprising for $30, but they both have their flaws and some explanation is required. In the 100Hz-500KHz range the TC6028 sounds better than one PC83 and in the >3Khz range the TD20F sounds better than the PC83. In the <80Hz range the TC6028 BP6 sounds better than the TC6028 BR.

I tried to use the pure acoustic roll offs that are inherent in both designs to reduce component costs. The BP6+Fullrange has 3 pure acoustic slopes, while the 2way has 1 pure acoustic slope + 2 electrical slopes. The pure acoustic slopes, like the sealed Fullrange LF rolloff at 180Hz, are due to decreased efficiency. The same power is going to the driver at LF and it still moves alot, generates decreasing output, can exceed Xmax and the SQ suffers. You would not notice that SQ issue from the swept sine FR test. It also occurs in the BP6 below its VLF rolloff (needs a HP to prevent low power Xmax) and above its LF rolloff (MF residue, needs a LP). Music with a high VLF content would unload the TC6028 (both BP6 and BR), xmax may be exceeded, and SQ would suffer across its entire range. I was not expecting the "in band" SQ to suffer as the drivers see their "out of band" frequencies, and I was incorrectly expecting just an acoustic efficiency drop.

The 2way electrical XO actually decreases the power to the drivers in the range where they misbehave (out of band). So less misbehaviour and the SQ is better. In my next project (modular 3way) I plan on making the electrical XO dominant to avoid using the pure acoustic slopes. So every driver will have a bandpass and will only be fully powered for its intended "in band" well behaved range.

Last edited by DonVK; 25th September 2018 at 02:08 PM. Reason: format
  Reply With Quote

Reply


silk purse from sows ear contest?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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
A Silk Purse! Guarnera Digital Source 31 20th December 2015 06:21 PM
The silk purse project: a musical studio monitor ... fas42 Multi-Way 102 4th July 2012 01:26 AM
SILK 4" out to 20k RAW Multi-Way 18 30th April 2004 05:41 AM
DIY Silk screen maylar Solid State 3 20th March 2004 05:21 PM
silk purse from 2 sows' ears leadbelly Multi-Way 15 10th February 2003 01:40 PM


New To Site? Need Help?

All times are GMT. The time now is 11:28 PM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.00%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio
Wiki