#1
Hey there, so I've decided to make an attenuator for my new jvm210h. After browsing the interwebs it looks like I need an L-pad which does that actual attenuation. My question is how many watts do I need it rated for my 100w amp? I've seen people say at least double but some say around 150. Also, I would appreciate it if anyone has a diagram or guide, this will be my first time making or soldering anything for my guitar or amp.
#2
I'd generally not trust an L-pad for anything more powerful than 5-15W.

It's not expensive or difficult to build an attenuator (a resistive one, at least). An inductive attenuator (like the Webers that use a speaker motor) is probably better, but will cost you around $100 to build.

Here's one that I know will work: http://www.guitarplayer.com/miscellaneous/1139/power-attenuator-project/12561
#3
I'd generally not trust an L-pad for anything more powerful than 5-15W.

Quote by dspellman
I'd generally not trust an L-pad for anything more powerful than 5-15W.
It's not expensive or difficult to build an attenuator (a resistive one, at least). An inductive attenuator (like the Webers that use a speaker motor) is probably better, but will cost you around $100 to build.

Here's one that I know will work: http://www.guitarplayer.com/miscellaneous/1139/power-attenuator-project/12561


This^^ An L-pad will melt with 100w output unless you spend large $$$ on a really expensive one. Off the shelf is pretty reasonable and if you only cut 8-12db they sound pretty good. When people get in trouble is adding an attenuator, cutting 24db and expecting it to still sound like a big amp. It won't. They think there is something wrong with the attenuator making the amp sound weak but it was just a clueless loose spacer adjusting the knobs.
"Your sound is in your hands as much as anything. It's the way you pick, and the way you hold the guitar, more than it is the amp or the guitar you use." -- Stevie Ray Vaughan

"Anybody can play. The note is only 20 percent. The attitude of the motherfucker who plays it is 80 percent." -- Miles Davis

Guthrie on tone: https://www.youtube.com/watch?v=zmohdG9lLqY
Last edited by Cajundaddy at Sep 4, 2016,
#4
Quote by dspellman
I'd generally not trust an L-pad for anything more powerful than 5-15W.

It's not expensive or difficult to build an attenuator (a resistive one, at least). An inductive attenuator (like the Webers that use a speaker motor) is probably better, but will cost you around $100 to build.

Here's one that I know will work: http://www.guitarplayer.com/miscellaneous/1139/power-attenuator-project/12561


Quote by Cajundaddy
This^^ An L-pad will melt with 100w output unless you spend large $$$ on a really expensive one. Off the shelf is pretty reasonable and if you only cut 8-12db they sound pretty good. When people get in trouble is adding an attenuator, cutting 24db and expecting it to still sound like a big amp. It won't. They think there is something wrong with the attenuator making the amp sound weak but it was just a clueless loose spacer adjusting the knobs.


It looks like I can get an L-pad rated at 200w for $56 at 200w at https://www.madisoundspeakerstore.com/l-pads-attenuators/fostex-r82b-200w-l-pad/. Will this be enough? It looks like I'd spend the same amount on materials if I go with this or with the setup you suggested. It seems like an L-Pad gives you more control. All the parts ordered from mouser comes up to $105 after shipping.
#5
Quote by wellmandellie
It looks like I can get an L-pad rated at 200w for $56 at 200w at https://www.madisoundspeakerstore.com/l-pads-attenuators/fostex-r82b-200w-l-pad/. Will this be enough? It looks like I'd spend the same amount on materials if I go with this or with the setup you suggested. It seems like an L-Pad gives you more control. All the parts ordered from mouser comes up to $105 after shipping.


Those are specifically designed to control HF drivers after the xover above 800hz. Big fat waves of LF energy is what draws current and kills L-pads. Look deeper into the specs and if they rate it as a full range L-pad, give it a try. If it melts it's only a $60 lesson in electronics design and application.
"Your sound is in your hands as much as anything. It's the way you pick, and the way you hold the guitar, more than it is the amp or the guitar you use." -- Stevie Ray Vaughan

"Anybody can play. The note is only 20 percent. The attitude of the motherfucker who plays it is 80 percent." -- Miles Davis

Guthrie on tone: https://www.youtube.com/watch?v=zmohdG9lLqY
#6
Quote by Cajundaddy
Those are specifically designed to control HF drivers after the xover above 800hz. Big fat waves of LF energy is what draws current and kills L-pads. Look deeper into the specs and if they rate it as a full range L-pad, give it a try. If it melts it's only a $60 lesson in electronics design and application.


Is there any danger to the amp if anything melts or I make it wrong?
#7
Quote by wellmandellie
Is there any danger to the amp if anything melts or I make it wrong?


Of course.
#8
Worse case scenario, it melts the amp output transformer, catches fire, and burns your house down. But that hardly ever happens.
It might be simpler and cheaper to just turn down the master on your amp, and then warm up the sound with a little increased bass to compensate for the Fletcher-Munson curve. Attenuators are for amps that don't have a good master volume control. Yours does.
"Your sound is in your hands as much as anything. It's the way you pick, and the way you hold the guitar, more than it is the amp or the guitar you use." -- Stevie Ray Vaughan

"Anybody can play. The note is only 20 percent. The attitude of the motherfucker who plays it is 80 percent." -- Miles Davis

Guthrie on tone: https://www.youtube.com/watch?v=zmohdG9lLqY
Last edited by Cajundaddy at Sep 5, 2016,