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

Audio Physic Avantis and DIY improvements
Audio Physic Avantis and DIY improvements
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
Thread Tools Search this Thread
Old 18th September 2010, 04:25 AM   #1
jeffreybehr is offline jeffreybehr  United States
diyAudio Member
Join Date: Mar 2005
Location: Phoenix, Arizona USA
Default Audio Physic Avantis and DIY improvements

After enjoying a pair of (ugly) DIY open-baffle line-arrays for a few years, I decided I didn't have the energy to build good-looking ones, so I investigated a pair of speakers, the Audio Physic Scorpio, I heard and enjoyed at the '06 CES. Found them but also found a pair of the next-up-in-the-line Avanti IIIs close enough to listen to and bring home. These have turned into a fairly substantial improvement project.

Mine are in ebony...
Click the image to open in full size.
...and sounded quite good--and LOTS different than my OBLAs.

First thing I did was discover that all 3 sections of the 2 crossover boards are driven by separate cables all the way back to the binding posts. I separated the bass cable and drove that separately with an old-but-good Hafler 9120 poweramp (with level controls). Last week I started using a pair of Marantz MA-500 monoamps driven by the middle section of a dbx DriveRackPA digital speaker-management system I had been using with the OBLA system. (The MR/treble runs diredt from the preamp to the poweramps and NOT thru the dbx.) That allowed much experimentation with lower crossover points and some eqing, and this week I removed the original bass-only crossover boards and wired the bass drivers, four 16-ohm Peerless 7"ers, directly to the same kind of 11g. bass cable I've used on several projects.

Last week I removed the MR/treble crossovers from the boxes...
Click the image to open in full size.
...and rewired the tweeter and MR drivers with hi-quality Audioquest speakercable. I've temporarily wired a pot in series with the input of the tweeter section--the pot is now soldered to the board --to adjust its output; eventually probably I'll wire a rotary switch with various resistors to have treble output adjustable in perhaps-several levels.

Late this week I made the biggest improvement yet--I removed the hi-pass caps* from the 2 MR x-over sections** and 'replaced' them with 1-each new coupling caps in my 12-watt tubed monoamps***. I chose for this new coupling cap a lower hi-pass filterpoint to get a bit more lower-MR and upper-bass energy from the system. This was a resounding success. The sound is now a bit warmer but not at all thick, and a layer of obfuscation and grittiness has been removed from the sound. WOW!

I've ordered some custom-configured long spikes--of 8mm/1.25 thread--that'll go thru my carpet to the concrete below from Brass and Granite Audio ( Speaker Spikes Floor Cones Audio Tweaks Stands ). Yet to do is replace the 2 caps in series with the tweeter and improve some other x-over parts, but I'm VERY happy with these speakers.

I thank Jeffrey Glowacki of Sonic Craft for again assisting in pointing me in new directions and keeping me out of trouble.

Comments and suggestions are always welcome.

* 55uF of inexpensive plastic-film caps
** the lower of the 2 MR drivers handles lower MR only...about 200 - 500Hz; the other handles 200Hz - c. 2.5KHz.
*** Music Reference EM7-12 SET mono poweramps
  Reply With Quote
Old 18th September 2010, 06:34 AM   #2
jeffreybehr is offline jeffreybehr  United States
diyAudio Member
Join Date: Mar 2005
Location: Phoenix, Arizona USA
Default Here's a pic of that ugly OBLA system

Click the image to open in full size.
  Reply With Quote


Audio Physic Avantis and DIY improvementsHide 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
Why do Audio Physic prefer aluminum over magnesium cones? capslock Multi-Way 6 9th December 2009 09:35 AM
audio note P1SE improvements Charles Wasserf Tubes / Valves 0 1st September 2008 07:07 PM
Speakers like Audio Physic and VA? seve Multi-Way 0 5th August 2005 08:23 PM
DIY Music from DIY Live Audio Gear peterpan73 Parts 7 13th April 2004 06:55 AM
Audio Physic Virgo baffle thickness? Nordmann Multi-Way 1 17th March 2002 12:40 AM

New To Site? Need Help?

All times are GMT. The time now is 01:12 PM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.79%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio