Myth Busters: 1000W amp is only twice as loud as a 100W amp - Page 4 - diyAudio
Go Back   Home > Forums > Amplifiers > Solid State

Solid State Talk all about solid state amplification.

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 13th January 2013, 08:17 AM   #31
JMFahey is offline JMFahey  Argentina
diyAudio Member
 
JMFahey's Avatar
 
Join Date: Mar 2009
Location: Buenos Aires - Argentina
Let me add that in the PA world they use very good and properly set limiters , same with crossovers, and they avoid clipping like the plague.
They have the tools , of course.
Anybody who does not care, soon has a series of very expensive "lessons" teaching him.
  Reply With Quote
Old 13th January 2013, 08:49 AM   #32
balerit is offline balerit  South Africa
diyAudio Member
 
balerit's Avatar
 
Join Date: Apr 2011
Location: South Africa
Quote:
Originally Posted by cotdt View Post
In the PA world, they use amps with twice the power handling of the speaker to avoid this. In the hifi world, whose ears are going to take heavy clipping continuously long enough to blow a tweeter? Today's tweeters could also handle more power than in the past.
Only with the correct crossover, tweeters can only handle about 5w.
  Reply With Quote
Old 13th January 2013, 01:52 PM   #33
JMFahey is offline JMFahey  Argentina
diyAudio Member
 
JMFahey's Avatar
 
Join Date: Mar 2009
Location: Buenos Aires - Argentina
Agree, and forgot one extra detail: *standard* practice in mid price PA cabinets, such as those bought and operated by Musicians themselves (vs. hiring a Pro Sound Company) is to add a power limiting car type lamp in series with the tweeters, just in case the operator is careless.
So much so, that typical 12V 15W car lamps are called "Tweeter Lamps" in speaker accessories catalogs.
For those interested in the Math, such lamps dynamically limit current to slightly over 1A, so 8/10W *max* into the tweeter.
Any extended abuse and the lamp blows like a fuse.
  Reply With Quote
Old 13th January 2013, 02:03 PM   #34
djk is offline djk
diyAudio Member
 
djk's Avatar
 
Join Date: Feb 2001
Location: USA
"under powered amps will blow tweeters in no time flat. "

It's not the clipping of the underpowered amp that causes the tweeter to blow.

It is either the increase in long-term average-power of the undistorted portion of the program material, or mechanical damage to the tweeter that causes it to fail (single-strand lead-out wire).

The increase in HF from the bass line clipping the amplifier is of short duration and trivial compared to the increase in average power during the much longer time the amplifier is not clipping.

From examining thousands of tweeters that failed over a 30+ year period of time, and deliberately trying to blow tweeters on the bench, I can recognize the failure mode from an autopsy.
__________________
Candidates for the Darwin Award should not read this author.

Last edited by djk; 13th January 2013 at 02:06 PM.
  Reply With Quote
Old 13th January 2013, 02:11 PM   #35
djk is offline djk
diyAudio Member
 
djk's Avatar
 
Join Date: Feb 2001
Location: USA
"Any extended abuse and the lamp blows like a fuse. "

Use the #211-2 (about 1A) to protect an 8Ω 1" voice-coil.

Use the #1156 (about 2A) to protect an 8Ω 1-3/4" voice coil.
__________________
Candidates for the Darwin Award should not read this author.
  Reply With Quote
Old 13th January 2013, 04:42 PM   #36
diyAudio Member
 
kevinahcc20's Avatar
 
Join Date: Apr 2009
Location: Farmington Hills, MI USA
Quote:
Originally Posted by cotdt View Post
And what if you listened to the concert when you were 20 years old, fell in love with the music, and now you are 65 years old, and you listen to the reproduction of said music? The reproduction would sound vastly different from the music you fell in love with when you were young.
Only if you have a superhuman ability to precisely remember sound details from years ago...but our brains don't work that way. That is why anecdotal reports of "this (cable/capacitor/Shakti stone/etc.) sounds better than that one" are unreliable without closely controlled listening tests in close sequence. Hearing is a very accommodative sense and the gradual shelving down of high frequencies over decades is more subtle than you would think. Only when the losses reach down into the mid-frequencies that are critical for speech comprehension do we notice, and even then many geezers will insist that they are hearing fine and the problem is that everyone around them mumbles. As a 60 year old who now wears hearing aids, you may be assured that I speak from experience.
__________________
Kevin(ahcc20)...I'd rather have a bottle in front of me than a frontal lobotomy!
  Reply With Quote
Old 13th January 2013, 05:49 PM   #37
a.wayne is offline a.wayne  United States
diyAudio Member
 
a.wayne's Avatar
 
Join Date: May 2008
Location: Front Row Center
While it is reconized that 10db is the difference to sound twice as loud this does not compensate for percussive energy. Easy to understand , listen to 6.5 fullrange driver playing at 93 db and then a big fullrange system playing at that same 93 db..

The loudness perception will be different for both ....

Quote:
Originally Posted by cotdt View Post
I see that people need some treble boost as older, especially males!

People age 65 lose at least 6dB hearing at all frequencies, 40dB (!) hearing at higher frequencies! This means older people need an amp with 4x the wattage.
Funny , i use less now than at 25, listen to music now at a lower level and can still hear 16k last hearing test ...

I'm almost as old as Pano and dirt ...

Quote:
Originally Posted by djk View Post
"Any extended abuse and the lamp blows like a fuse. "

Use the #211-2 (about 1A) to protect an 8Ω 1" voice-coil.

Use the #1156 (about 2A) to protect an 8Ω 1-3/4" voice coil.

I usually use a 10 amp speaker fuse to protect my amplfiers ...
__________________

Last edited by a.wayne; 13th January 2013 at 05:57 PM.
  Reply With Quote
Old 13th January 2013, 06:40 PM   #38
djk is offline djk
diyAudio Member
 
djk's Avatar
 
Join Date: Feb 2001
Location: USA
A 10A fuse is worthwhile with a Hafler 500 sized amplifier faced with a dead short, been there, done that.
__________________
Candidates for the Darwin Award should not read this author.
  Reply With Quote
Old 13th January 2013, 06:44 PM   #39
balerit is offline balerit  South Africa
diyAudio Member
 
balerit's Avatar
 
Join Date: Apr 2011
Location: South Africa
Quote:
Originally Posted by djk View Post
"under powered amps will blow tweeters in no time flat. "

It's not the clipping of the underpowered amp that causes the tweeter to blow.

It is either the increase in long-term average-power of the undistorted portion of the program material, or mechanical damage to the tweeter that causes it to fail (single-strand lead-out wire).
What do you think clipping is, it's the increase in average power when the top of the sine wave is cut off almost approximating a square wave.
  Reply With Quote
Old 13th January 2013, 06:51 PM   #40
diyAudio Member
 
Wavebourn's Avatar
 
Join Date: Sep 2006
Location: Pleasant Hill, CA
Send a message via Skype™ to Wavebourn
Hmmm... I have very good and well trained hearing. Can reproduce frequency by memory. Can hear distortions, imagine waveform, and guess schematic that can produce such distortions. But how can I tell if the sound is louder TWICE, but not say 1.8 times, nor 3 times? I have no scale to measure. Who really does? I am curious.

Quote:
Originally Posted by kevinahcc20 View Post
Only if you have a superhuman ability to precisely remember sound details from years ago...but our brains don't work that way.
Mine does. I remember mom's, dad's voices, voices of my friends, sounds of gramophone, sounds of different radio receivers, guitar amps, studio reproduction of our ensemble when we were recorded, and so on. I am 55 now, and remember at least 50 years' old sounds.

...but I don't hear differences in cables. :-)
__________________
The Devil is not so terrible as his math model is!

Last edited by Wavebourn; 13th January 2013 at 06:58 PM.
  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
100w to 1000w class ab wattaniya Solid State 81 12th February 2014 02:20 PM
solid state amp warm-up time, myth or fact? AJT Solid State 100 16th December 2012 10:19 AM
Why can 8W sound as loud as 100W? AudioIsFun Tubes / Valves 19 26th January 2004 03:05 PM


New To Site? Need Help?

All times are GMT. The time now is 03:11 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