Subwoofer Tests Round 5, 6th of October 2007, Test Summary ***READ ME*** - Page 3 - Home Theater Forum and Systems - HomeTheaterShack.com

 
Thread Tools
post #21 of 71 Old 12-27-07, 04:11 PM
Shackster
 
texfrazer's Avatar
Tex
 
Join Date: Oct 2006
Location: Knoxville, TN
Posts: 46
Re: Subwoofer Tests Round 5, 6th of October 2007, Test Summary ***READ ME***

Once again, you have outdone yourself!!!! Thanks!!!!
texfrazer is offline  
Sponsored Links
Advertisement
 
post #22 of 71 Old 12-29-07, 01:25 AM Thread Starter
Elite Shackster
 
Ilkka's Avatar
Ilkka
 
Join Date: Jun 2006
Location: Finland
Posts: 1,468
Re: Subwoofer Tests Round 5, 6th of October 2007, Test Summary ***READ ME***

Quote:
croseiv wrote: View Post
Why no 115 dB sweep for the Ultra? Just curious.
I tried it but the internal fuse blew right after the start (same thing happened during the AV Talk tests so I was sort of expecting it). Same thing happened during the 110 dB when using the sealed mode (at around 14 Hz).
Ilkka is offline  
post #23 of 71 Old 12-29-07, 01:25 AM Thread Starter
Elite Shackster
 
Ilkka's Avatar
Ilkka
 
Join Date: Jun 2006
Location: Finland
Posts: 1,468
Re: Subwoofer Tests Round 5, 6th of October 2007, Test Summary ***READ ME***

Hi all,

I'm heading out on a short New Year holiday so I won't be online for a few days. But when I'm back, I will tackle all the questions regarding the subwoofers measurements you have made.

Happy New Year to everyone!
Ilkka is offline  
 
post #24 of 71 Old 12-29-07, 12:07 PM
Shackster
chuck
 
Join Date: Nov 2007
Posts: 24
Re: Subwoofer Tests Round 5, 6th of October 2007, Test Summary ***READ ME***

Quote:
Ilkka wrote: View Post
I tried it but the internal fuse blew right after the start (same thing happened during the AV Talk tests so I was sort of expecting it). Same thing happened during the 110 dB when using the sealed mode (at around 14 Hz).

Okay. Thanks for the info.
croseiv is offline  
post #25 of 71 Old 12-31-07, 01:33 PM
Shackster
 
darrellh44's Avatar
Darrell
 
Join Date: Aug 2007
Location: North Dallas
Posts: 74
Re: Subwoofer Tests Round 5, 6th of October 2007, Test Summary ***READ ME***

Hi Ilkka,

Do you have the means to measure/record amplifier and sub output distortion at the same time. For your next round of tests, it would be informative to see how much distortion/compression the amp is contributing along side the sub measurements. It seems like the CSS 2xSDX15 had an unfair advantage in the latest round of testing since it used two CE4000s. Since it's impractical to use two amps with every sub, at least knowing a single-amp sub's input distortion would help interpret the overall results.
darrellh44 is offline  
post #26 of 71 Old 01-03-08, 09:01 PM
jakeman
Inactive
 
Posts: n/a
Re: Subwoofer Tests Round 5, 6th of October 2007, Test Summary ***READ ME***

Quote:
Ilkka wrote: View Post
Hi all,

I'm heading out on a short New Year holiday so I won't be online for a few days. But when I'm back, I will tackle all the questions regarding the subwoofers measurements you have made.

Happy New Year to everyone!
Hi Illka

Trust you had a Happy New Year and a relaxing holiday. I was idling away some time today during my ski trip here in the Canadian Rockies and went looking for some spectral contamination charts for your latest sub tests and see you have not posted them. While I agree with you that the cross-section of charts does provide a pretty good indication of performance, I found the spectral contamination charts useful as all encompassing charts of distortion and noise.

As per your definition;
Quote:
Spectral contamination test will show all non-linear distortions and mechanical ‘self-noises’ (panel vibrations, driver motor noise, port noise etc.). Also the limiting circuits often became very audible during this test.
While many readers may not appreciate its significance, this chart does provide a very useful measurement of real time performance. Generally speaking, many larger subs at higher output can produce significant port or resonance noise and do not fair as well as other subs such as several sealed subs in this area. Accordingly, it would be useful information when comparing the relative performance at high output between these two types of alignment and also among vented subs.
post #27 of 71 Old 01-05-08, 02:47 AM Thread Starter
Elite Shackster
 
Ilkka's Avatar
Ilkka
 
Join Date: Jun 2006
Location: Finland
Posts: 1,468
Re: Subwoofer Tests Round 5, 6th of October 2007, Test Summary ***READ ME***

Quote:
allredp wrote: View Post
Which one would you buy for yourself, representing the best cost/performance ratio?
If looking at the commercial subwoofers only, the SVS PB13-Ultra stands out as having a very high cost/performance ratio. But then again it's physically quite large so it doesn't come without expenses. For example the JL Audio Fathom f113 represents another kind of approach: it's very small yet very powerful subwoofer. Then again it costs much more than the PB13-Ultra. Pick your poison, as they say.
Ilkka is offline  
post #28 of 71 Old 01-05-08, 02:50 AM Thread Starter
Elite Shackster
 
Ilkka's Avatar
Ilkka
 
Join Date: Jun 2006
Location: Finland
Posts: 1,468
Re: Subwoofer Tests Round 5, 6th of October 2007, Test Summary ***READ ME***

Quote:
rubbersoul wrote: View Post
I to am curious as to your personal opinion on the JL Audio Fathom 113....I happened to buy one a month ago and recently as Dec 23rd actually got to calibrate it and use it and I was blown away. It has everything I think a sub should be.
Feel free to sendind a PM.

Merry Christmas to everyone!!!!

Frank
Quote:
tweakophyte wrote: View Post
Now... was the JLA's distortion that audible? In other areas people have compared that sub to the Ultra... now I am doubting their ears
I'll reply to these in the Fathom f113's own test thread.

http://www.hometheatershack.com/foru...-f113-new.html
Ilkka is offline  
post #29 of 71 Old 01-05-08, 03:03 AM Thread Starter
Elite Shackster
 
Ilkka's Avatar
Ilkka
 
Join Date: Jun 2006
Location: Finland
Posts: 1,468
Re: Subwoofer Tests Round 5, 6th of October 2007, Test Summary ***READ ME***

Quote:
darrellh44 wrote: View Post
Hi Ilkka,

Do you have the means to measure/record amplifier and sub output distortion at the same time. For your next round of tests, it would be informative to see how much distortion/compression the amp is contributing along side the sub measurements. It seems like the CSS 2xSDX15 had an unfair advantage in the latest round of testing since it used two CE4000s. Since it's impractical to use two amps with every sub, at least knowing a single-amp sub's input distortion would help interpret the overall results.
When it comes to commercial subs, it's not possible since I would have tear them apart to be able to access the speaker wires. DIY subs with external power amplifiers are another case; it would be possible to measure and record the amplifier distortion, and in fact I have some preliminary plans for this.

I wouldn't say the dual CSS SDX15 had an unfair advantage since it used two amplifiers. DIY means that one can use as much power as his wallet allows so I decided to see how far I could push those woofers. And as you can see from the results, the woofers became the limiting factor, not the amplifier power. Also remember that 2x power means only 3 dB higher output.
Ilkka is offline  
post #30 of 71 Old 01-05-08, 03:53 AM Thread Starter
Elite Shackster
 
Ilkka's Avatar
Ilkka
 
Join Date: Jun 2006
Location: Finland
Posts: 1,468
Re: Subwoofer Tests Round 5, 6th of October 2007, Test Summary ***READ ME***

Quote:
jakeman wrote: View Post
Hi Illka

Trust you had a Happy New Year and a relaxing holiday.
Thank you, John!

Quote:
While many readers may not appreciate its significance, this chart does provide a very useful measurement of real time performance. Generally speaking, many larger subs at higher output can produce significant port or resonance noise and do not fair as well as other subs such as several sealed subs in this area. Accordingly, it would be useful information when comparing the relative performance at high output between these two types of alignment and also among vented subs.
Both ported and sealed subs can (and usually will) start to sound stressed when pushed high enough. Whether this is port chuffing, amp clipping, driver noise etc, it's always not wanted and usually very audible. But neither me or the results I have measured won't agree that larger (ported) subs would be more prone to these kind of noises than small sealed subs. Instead of being a size or an alignment difference, it's usually noticed because some subwoofers have much aggressive and/or transparent output limiters than other subwoofers. Some subwoofers can be pushed several dB into compression without sounding stressed or outputting excessive distortion. Some others let the amplifier clip and/or the woofer excursion run out, and that will usually sound much worse than heavy limiting. In either case, the subwoofer is being overdriven and it isn't operating in its linear range anymore. If this happens constantly, you should buy one more subwoofer (or more if even two won't give you enough clean output).
Ilkka is offline  
 

Bookmarks

Tags
2007 , 6th , october , read , round , subwoofer , summary , test , tests

Quick Reply
Message:
Options

Register Now




PLEASE COMPLETE ALL REQUIRED FIELDS BELOW... THANKS!

REQUIRED FIELDS ON THIS PAGE
YOU MUST COMPLETE ALL OF THESE

Username
Password
Confirm Password
Email Address
Confirm Email Address
Random Question
Random Question #2




User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
PLEASE READ BELOW PRIOR TO ENTERING AN EMAIL ADDRESS!

ATTENTION!

YOU MUST ACTIVATE YOUR ACCOUNT!

Activation requires you reply to an email we will send you after you register... if you do not reply to this email, you will not be able to view certain areas of the forum or certain images... nor will you be able download software.

AN INVALID EMAIL ADDRESS WILL CAUSE YOUR ACCOUNT TO BE DELETED!

See our banned email list here: Banned Email List

We DO NOT respond to spamcop, boxtrapper and spamblocker emails... please add @hometheatershack DOT com to your whitelist prior to registering or you will get nowhere on your registration.


Email Address:
OR

Log-in









Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



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 is not allowed!
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

 


For the best viewing experience please update your browser to Google Chrome