Capacitor audibility: fact or fiction? - 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 8th September 2010, 10:03 PM   #1
jcandy is offline jcandy  United States
diyAudio Member
 
jcandy's Avatar
 
Join Date: Feb 2009
Location: San Diego
Default Capacitor audibility: fact or fiction?

In the last few days I have been trying to sort out the issue of capacitor choice for use in passive crossovers. There seems to be an inordinate number of people (both seasoned designers and technically incompetent "audiophiles" alike) who express strong opinions and actual preferences for certain capacitors. For example, bizarre claims like "Xcap really opens up the speaker while Ycap sounds gritty" are not uncommon. Yet, I can find ZERO objective testing data. Not a single SPL trace.

Does anybody have some objective data on this issue. I've heard all the opinion, now I'd love to hear some facts.
__________________
"Beer makes you feel the way you ought to feel without beer." - Henry Lawson
  Reply With Quote
Old 8th September 2010, 10:27 PM   #2
diyAudio Member
 
dantheman's Avatar
 
Join Date: May 2008
Location: Mountain View, CA
There is some evidence that caps can have an audible effect:

AES E-Library: Audio Capacitors. Myth or Reality?
and this discussion on it makes it seem more dubious:
Need impressions of capacitors
Then there is this:
ABX Double Blind Test Results: Capacitors

Don't set fire to your caps!

Dan
__________________
My Blog
My Music Recordings
  Reply With Quote
Old 8th September 2010, 10:40 PM   #3
badman is offline badman  United States
diyAudio Member
 
badman's Avatar
 
Join Date: Sep 2003
Location: Sunny Tustin, SoCal
Note that the listener environment was critical in the results... I've always said that listening in a home system at your leisure makes differences much easier to hear and interpret.
__________________
I write for www.enjoythemusic.com in the DIY section. You may find yourself getting a preview of a project in-progress. Be warned!
  Reply With Quote
Old 8th September 2010, 11:04 PM   #4
jcandy is offline jcandy  United States
diyAudio Member
 
jcandy's Avatar
 
Join Date: Feb 2009
Location: San Diego
No doubt a poorly-made capacitor will exhibit non-capacitive artifacts (that is, it will behave in a non-ideal way). I'm surprised we haven't seen anyone do some SPL and distortion sweeps using a selection of audiophile-grade polypropylene capacitors using a simple, say, high-pass filter. When corrected for differences in capacitance (there will be small variances in overall capacitance which could bias some tests), it seems very unlikely to me that differences are audible. But who can say without the data?
__________________
"Beer makes you feel the way you ought to feel without beer." - Henry Lawson
  Reply With Quote
Old 8th September 2010, 11:08 PM   #5
RIP
 
pedroskova's Avatar
 
Join Date: Dec 2002
Location: C'ville VA, USA
Steve Bench showed electrical differences between different cap constructions on an O-scope -- his site is archived somewhere on the web.
  Reply With Quote
Old 8th September 2010, 11:52 PM   #6
diyAudio Member
 
Join Date: Feb 2004
Location: Queensland Australia
Many years ago when "AudioXpress" was just a monochrome "Audio Amateur" there were CRO results published. Cyril Bateman in "Electronics and Wireless World" UK did harmonic distortion measurements a few years ago. (Magazine now may be called by another name.....) The same mag published work on the effects of the mechanical changes in the dialectric and how that might change the results. That was more recent. "Audio" also published distortion results for ceramic caps, I think. That would be 30 yrs old now.
But what is more interesting is the dynamic effects that are harder (or impossible) to see in steady state results.
There is a decisive result in this country (Australia) of how a large polyester cap had a quite distinct "memory" of a previous charge appear after the operators had assumed it had been fully discharged. Can't quote chapter and verse off hand. But it is that sort of quality that makes some of us suspect that we are hearing a "smearing" or other change when comparing caps of different types.
I know some of the terminology is a bit vague but I am committed to serious hard science and that when we know what to look for and how to measure it appropriately then things will appear more rigorous.
__________________
"It was the Springtime of the year when aunt is calling to aunt like mastodons bellowing across primeval swamps." P.G. Wodehouse.
  Reply With Quote
Old 9th September 2010, 01:08 AM   #7
diyAudio Member
 
dantheman's Avatar
 
Join Date: May 2008
Location: Mountain View, CA
Check this out as well:
http://www.classicspeakerpages.net/I...e=post&id=5415

Badman, have you read the AES article? If so, could you summarize it a bit?

Thanks,

Dan
__________________
My Blog
My Music Recordings
  Reply With Quote
Old 9th September 2010, 01:35 AM   #8
diyAudio Member
 
Join Date: Nov 2005
The classics:
http://waltjung.org/PDFs/A_RealTime_...or_Quality.pdf

http://waltjung.org/PDFs/Picking_Capacitors_1.pdf

http://waltjung.org/PDFs/Picking_Capacitors_2.pdf

I realize with surprise that I am very weary of such posts and discussions. I guess I'm coming to feel:
Try it yourself, with some moderately highly recommended types, and some with bad reviews, in the crossover prototype. Use good assembly practice, good solder joints, star ground, etc., installing all the "good" and then all the "bad" caps; or just build two prototypes. If you hear a difference, it exists, if not it doesn't. If you're not willing to try it yourself, then the (no doubt unworthy) suspicion of trolling is raised.

Last edited by Curmudgeon; 9th September 2010 at 01:49 AM. Reason: Added 2nd para.
  Reply With Quote
Old 9th September 2010, 01:38 AM   #9
diyAudio Member
 
Join Date: Feb 2002
Location: Western Sydney
buy a couple of pairs of caps and a switch.....
__________________
Impedance varies with frequency, use impedance plots of your drivers and make crossover calculations using the actual impedance of the driver at the crossover frequency
  Reply With Quote
Old 9th September 2010, 01:43 AM   #10
Pano is offline Pano  United States
diyAudio Moderator
 
Pano's Avatar
 
Join Date: Oct 2004
Location: Kona, Hawaii
Blog Entries: 4
There was a rather good article with great measurements of caps posted on here a little while ago. Will see if I can find it.

Also check out the polypro vs ceramic files in the demo downloads of Audio DiffMaker. Both are compared to a piece of wire.
Audio DiffMaker
__________________
Big Altec Moving Sale!
  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
Class A electronics ban?? fact or fiction qusp Solid State 118 5th February 2013 10:43 PM
Burning/running in, fact or fiction? nad Solid State 47 17th January 2010 10:31 PM
Extemis - Fact of Fiction sbolin Multi-Way 15 23rd January 2005 04:29 PM
load line - truth or fiction tenderland Tubes / Valves 4 29th July 2004 04:08 PM
Found on Ebay - fact or fiction? Nuuk Multi-Way 53 24th April 2004 07:10 PM


New To Site? Need Help?

All times are GMT. The time now is 08:30 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