Bare Knuckle Pickups Forum

Forum Ringside => Guitars, Amps and Effects => Topic started by: willo on January 17, 2006, 11:16:48 PM

Title: Amp Myths
Post by: willo on January 17, 2006, 11:16:48 PM
Here's a cool website I found debunking some of the common myths regarding amplification. I'm sure quite a few of you here already know all this, but I'm sure plenty of people may find some of it surprising.

http://www.guitarnuts.com/amps/myths.php

 :D
Title: Amp Myths
Post by: indysmith on January 17, 2006, 11:18:50 PM
hey thanks for that man! i'll be having a read
Title: Amp Myths
Post by: froglord on January 17, 2006, 11:25:15 PM
Good site, Willo.

ALL guitarists should know about the wattage thing. So many people write off "low" wattage amps for gigging based on a misconception that watts are a linear indication of loudness.
Title: Amp Myths
Post by: willo on January 17, 2006, 11:28:30 PM
Quote from: froglord
ALL guitarists should know about the wattage thing. So many people write off "low" wattage amps for gigging based on a misconception that watts are a linear indication of loudness.


Indeed, I learnt that off my electrician brother-in-law. He explained to me that doubling the wattage DID NOT mean doubling the volume. It's hard to get your head around - you'd think the increase was directly proportional - but, well, it's not. Still don't exactly understand why, although I'm sure HJM explained it a while back, something about 100W being 3db louder than a 50W, and a db is an audible (to the human ear) difference in volume. I think :?
Title: Amp Myths
Post by: froglord on January 17, 2006, 11:37:17 PM
Quote from: willo
something about 100W being 3db louder than a 50W...


No - 3dB more is a doubling of volume.

The problem is that - as far as volume is concerned - watts aren't linear, decibels aren't linear, bloomin' nothing's linear! It's no wonder people get confused.
Title: Amp Myths
Post by: willo on January 17, 2006, 11:50:20 PM
Quote from: froglord
Quote from: willo
something about 100W being 3db louder than a 50W...


No - 3dB more is a doubling of volume.

The problem is that - as far as volume is concerned - watts aren't linear, decibels aren't linear, bloomin' nothing's linear! It's no wonder people get confused.


ha...i thought I had it sussed! Meh...I'm only a guitarist, I just stomp on boxes and hit strings. All this electronic stuff baffles me :P
Title: Amp Myths
Post by: lulusg on January 18, 2006, 01:41:03 AM
It has been a long time since I read it, but I think that the brain measures or translates the changes in acoustics in a Logaritmic way. I think.
Title: Amp Myths
Post by: HJM on January 18, 2006, 12:43:52 PM
10db is a doubling of percieved volume, 3db doubling of wattage.
Title: Amp Myths
Post by: froglord on January 18, 2006, 01:23:44 PM
Quote from: HJM
10db is a doubling of percieved volume, 3db doubling of wattage.


Oh, bum. So I still don't understand it.  :D
Title: Amp Myths
Post by: The amazing Phil on January 18, 2006, 04:14:18 PM
That's pretty awesome, and it's deffinitely worth getting the word out there. I already knew a lot of that thankfully, but it's suprising how people get set in their ways. The stuff about "all tube" circuits was something I wasn't aware of though.
Title: Amp Myths
Post by: Ratrod on January 18, 2006, 04:23:51 PM
Many so called 'all tube' amps have a solid state rectifier. Oh well, as long as it sounds good.

If there's anyone who thinks his small combo isn't good enough, hook it up to a speaker cabinet before you buy a new amp.
Title: Amp Myths
Post by: The amazing Phil on January 18, 2006, 04:28:01 PM
Hell yeah, I've been tempted to take my C7 combo down to Coda and see if they'll let me run it through an Orange 4X12 to see how it sounds.
Title: Amp Myths
Post by: _tom_ on January 18, 2006, 05:11:31 PM
haha, this site looks like Another Job for the Mythbusters Team!! Mythbusters is awesome!
Title: Amp Myths
Post by: 38thBeatle on January 18, 2006, 07:39:32 PM
That was a great site Willo. It made me smile a bit remembering a guy I used to play in a band with years ago who had a rich father and whatever gear he decided he wanted and when he went to buy a 100w amp cost it would be "twice as loud" as the other guitarists 50w amp.
Title: Amp Myths
Post by: FELINEGUITARS on January 18, 2006, 07:42:43 PM
I always thought that a 10W amp was half as loud as a 100W amp due to the non linear thing.
Title: Amp Myths
Post by: dave_mc on January 18, 2006, 08:54:41 PM
Quote from: Ratrod
Many so called 'all tube' amps have a solid state rectifier. Oh well, as long as it sounds good.


yeah, most modern, high gain all-tube amps have ss rectification. things like vox ac30's have tube rectos...

And, yeah, feline, i think doubling the volume means (approximately) multiplying the wattage by 10.

EDIT: my savage se has a half power switch (switches from pentode to triode operation), and it's definitely not "twice" as loud in full power mode- it's "perceptibly" louder...
Title: Amp Myths
Post by: schmendict on January 18, 2006, 09:55:17 PM
My god, what a fool ive been.
I was once a "hormonal weenie" when it comes to amps, but now i have been enlightened. I didnt think 65w was loud enough for gigging....but now im just so happy.
Hoorah!!!
Title: Amp Myths
Post by: tewboss on January 18, 2006, 09:56:28 PM
anyway you can always mic an amp
Title: Amp Myths
Post by: sambo on January 18, 2006, 10:04:28 PM
me exactly same as tmhh (too much hiphop) lol.

what amp do you have tmhh?? i cant think of many amps with 65watts apart from my crate gt65..
Title: Amp Myths
Post by: balde on January 19, 2006, 12:56:12 AM
Quote from: FELINEGUITARS
I always thought that a 10W amp was half as loud as a 100W amp due to the non linear thing.


I think thatīs correct too...
Title: Amp Myths
Post by: sambo on January 19, 2006, 08:19:46 AM
yer a 10 watt amp is half as loud as a 100watt.
Title: Amp Myths
Post by: HJM on January 19, 2006, 11:58:20 AM
Quote from: FELINEGUITARS
I always thought that a 10W amp was half as loud as a 100W amp due to the non linear thing.


Yep - 10dB rule...10-100w is 10dB, 50 to 100 is closer to 3dB
Title: Amp Myths
Post by: Gary on January 19, 2006, 06:42:15 PM
I run my 40w amp through a hot plate set to -8dB for normal gigging levels. Does this mean that an equivalent 10w amp with no attenuation would be louder (all other things being equal)?
Title: Amp Myths
Post by: Kilby on January 19, 2006, 07:49:29 PM
Jeez Ive been calculating the loss of a wifi signal through 2 stud walls, 2 windows and a 75 meter airgap.

Please allow me to escape such calculations

rob...
Title: Amp Myths
Post by: MDV on January 25, 2006, 04:08:15 PM
3 db is double real normal hearing type percieved volume.

3.05db really, but hey, who really cares that much?