Full range Open Baffle with Current Drive - Page 3 - diyAudio
Go Back   Home > Forums > Loudspeakers > Full Range

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 15th November 2010, 12:10 PM   #21
knutn is offline knutn  Norway
diyAudio Member
 
Join Date: Mar 2006
Location: Oslo
Default Series resistance

With current drive you don't need any series resistance, so all the power is delivered to the driver. And you can manipulate the Q value actively or passively, as e.g. in Pass' FIRST WATT F1, where a resistor in parallel with the amplifier output does the job.
  Reply With Quote
Old 15th November 2010, 05:54 PM   #22
The one and only
 
Nelson Pass's Avatar
 
Join Date: Mar 2001
Quote:
Originally Posted by el`Ol View Post
I also think series resistors are bad per se. My main 3-way system runs with a low Qts wideranger and 3.3 Ohm series resistor that brings it to Qts = 0.5. Sounds much less stressed, much more relaxed.
I have run into this observation more than once - Jon ver
Halen has commented that series resistance "sucks the life
out" as an example.

And yet Thevenin equivalency is clear that there is no
difference between a perfect voltage source in series with
a resistor and a perfect current source in parallel with the
same resistor. If there is a difference then we have to
presume that there is either a failure in the perfection of
the cs and/or vs or a flaw in the test / listener.

  Reply With Quote
Old 15th November 2010, 06:49 PM   #23
diyAudio Member
 
Join Date: Mar 2002
> "sucks the life out"

In my experience it not only sucks the life out,
it also mangles the remaining cadaver.
However, a bypass cap seems to raise the dead
to a great extent.
  Reply With Quote
Old 15th November 2010, 07:42 PM   #24
el`Ol is offline el`Ol  Germany
diyAudio Member
 
Join Date: May 2005
Location: Bavarian Forest
Quote:
Originally Posted by el`Ol View Post
I also think series resistors are bad per se. My main 3-way system runs with a low Qts wideranger and 3.3 Ohm series resistor that brings it to Qts = 0.5. Sounds much less stressed, much more relaxed.
Sorry, I didn't post carefully enough. Wanted to say "I also don't think series are bad per se. But that too high values "suck out life" is true. The character of this driver before was a bit what a naim lover calls "energy", I don't like that kind of sound. I didn't make such experiments with other drivers, but with this driver +/- 0.3 Ohm was clearly audible (in the midrange, I don't speak about bass response). Are there different paper mixes that demand weaker/stronger motors?
  Reply With Quote
Old 15th November 2010, 08:03 PM   #25
diyAudio Member
 
nicoch58's Avatar
 
Join Date: Oct 2004
Knuts the new seas will be in the 125$ range....

Papa, Watt's next?
__________________
Sic58
  Reply With Quote
Old 15th November 2010, 10:11 PM   #26
Vix is offline Vix  Yugoslavia
diyAudio Member
 
Vix's Avatar
 
Join Date: Nov 2003
Location: Somewhere on Planet Earth
Quote:
Originally Posted by Nelson Pass View Post
And yet Thevenin equivalency is clear that there is no
difference between a perfect voltage source in series with
a resistor and a perfect current source in parallel with the
same resistor.
"In theory, there is no difference between theory and practice. But, in practice, there is." -Yogi Berra

By the way, I noticed that even simple L/R circuits that are used in series with the fullrange speaker in order to 'correct' their frequency response degrade the sound. Theoretically, they should be just shelving frequencies above the certain point, but...they suck some life out the music. That's why I prefer current source amps, and I (again) removed the feedback resistors (and CCS modulation) from my Zen V9.
  Reply With Quote
Old 16th November 2010, 01:26 PM   #27
knutn is offline knutn  Norway
diyAudio Member
 
Join Date: Mar 2006
Location: Oslo
Default Equalization

Quote:
Originally Posted by Vix View Post
"In theory, there is no difference between theory and practice. But, in practice, there is." -Yogi Berra

By the way, I noticed that even simple L/R circuits that are used in series with the fullrange speaker in order to 'correct' their frequency response degrade the sound. Theoretically, they should be just shelving frequencies above the certain point, but...they suck some life out the music. That's why I prefer current source amps, and I (again) removed the feedback resistors (and CCS modulation) from my Zen V9.
Have you tried active equalization instead of simple L/R circuits? What kind of speakers do you use, and how would you describe the difference between current drive and voltage drive?
  Reply With Quote
Old 16th November 2010, 05:40 PM   #28
Vix is offline Vix  Yugoslavia
diyAudio Member
 
Vix's Avatar
 
Join Date: Nov 2003
Location: Somewhere on Planet Earth
Yes, I tried equalization instead of simple L/R circuits. They do work, but any such circuits would require to be "sandwiched" between two buffer blocks for the best effect, which works well if you use J-fet (or even tube) buffers (I do not prefer opamps). My Open baffle (120x50cm-flat baffle) consists of The Eminence Beta 15 for the bass and Visaton B200 for the highs. It is biamped, so that the the Beta is driven by a voltage source amp (Sony TA-N511) while Visaton is driven by Zen V9 without feedback, i.e. current amp. The whole thing is now actively crossed over, though during the last two years I have been playing with various crossover combination (slopes, frequencies, active, passive, hybrid). The difference, V/I: Current drive changes the damping (hence bass) and the tonal character of the driver, often for the better. In my case, only the fullrange (above 150 Hz) is driven with the current amp, so no effect on the bass here, but some nice things happen in the upper registers as well. Somehow it sounds more musical, there is more "air', it just sounds more natural and less strident. Also, there is a bit of compensation here as well, in order to correct for fullrange nasties. There is Zobel (C+R) in parallell with speaker terminal (B200) to correct for its rising response.
On the paper, you would see that Zen V9 without feedback has actually more distortion than with feedback. However, at normal volumes I do not find it distracting. To me, connecting the feedback (this making it a conventional voltage amp) makes it sound more 'solid' and loose that 'breath of air that makes some instruments sound so lively....
I know it's all subjective, but...
  Reply With Quote
Old 17th November 2010, 08:07 PM   #29
knutn is offline knutn  Norway
diyAudio Member
 
Join Date: Mar 2006
Location: Oslo
Thank you for your feedback. Your description is a further encouragement for current drive!
  Reply With Quote
Old 17th November 2010, 09:53 PM   #30
The one and only
 
Nelson Pass's Avatar
 
Join Date: Mar 2001
Current source amplifiers are great for people who want to
play around with stuff. Not so great for those who just
want "plug and play"

  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
Full Range and the Semi-Open Baffle Capt Zach Full Range 26 29th June 2010 05:13 AM
Edge ? full range open baffle pforeman Full Range 3 12th June 2010 12:47 PM
Looking for Full Range for mid in Open Baffle dcathro Full Range 28 21st March 2010 04:44 AM
Building full range open baffle? Glowbug Full Range 27 22nd January 2007 11:15 PM
full range (open baffle) then_dude Full Range 15 9th March 2004 03:58 PM


New To Site? Need Help?

All times are GMT. The time now is 01:25 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