Author Topic: L-Pad Attenuator  (Read 14097 times)

sirbergersworth

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L-Pad Attenuator
« on: January 08, 2013, 08:54:13 PM »
I built this L-Pad attenuator yesterday. $15 8ohm/100watt L-Pad, a few $2 switches, jacks, couple of caps, wire from a broken computer power supply and a $5 aluminum enclosure.
I installed a true bypass switch on-off-on bright switch with a 4.7uf cap on one side and a 10uf cap. Both non polarized caps. All 18 gauge stranded wire. I haven't drilled holes for the venting yet but from my tests with my amps I will not need a fan. I wouldn't use this with anything over 15-20 watts.

I haven't decided on a paint job or decals yet. Any ideas?





I plan to use this with my vht special 6 head for very quiet bedroom levels (kids right above sleeping)
Tested last night and today and it works good. Worked just as well with a tweaker15 to be able to hit its sweet spot and not irritate the neighbors.
With the s6 it was very nice. I will be able to practice with a real amp instead of sims (don't own amp with headphone out)

Thanks for allowing me to brag.

Rob
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Guitar Master

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Re: L-Pad Attenuator
« Reply #1 on: January 08, 2013, 10:26:11 PM »
I got the same exact switches the other day! The switches look cool

stecykmi

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Re: L-Pad Attenuator
« Reply #2 on: January 08, 2013, 11:35:41 PM »
wow very cool project, i bet a lot of people are gonna be interested in this one.

Is it your design? source on the attenuator?

sirbergersworth

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Re: L-Pad Attenuator
« Reply #3 on: January 09, 2013, 12:15:31 AM »
.
Is it your design? source on the attenuator?

Not my design at all. I just googled "DIY attenuator" and found this page.
http://guitarprojects.weebly.com/diy-attenuator.html
i added two different bright switch options. I guess that's a mod ;-)
Very cool, cheap and useful project.
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sirbergersworth

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Re: L-Pad Attenuator
« Reply #4 on: January 09, 2013, 12:21:35 AM »
L-pad is here
http://www.parts-express.com/pe/showdetl.cfm?partnumber=260-262

There are other l-pads on parts express as well. Don't pay attention to wattage. These are intended to be a tweeter control after a crossover, etc.

One guy used a stereo 8ohm 100 watt and wired to switchable to 8.or 16 ohms. I can't find that link at the moment.
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alanp

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Re: L-Pad Attenuator
« Reply #5 on: January 09, 2013, 12:31:05 AM »
The layout for Ken Fischer's Trainwreck Airbrake is floating around the internet.
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Stomptown

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Re: L-Pad Attenuator
« Reply #6 on: January 09, 2013, 02:18:14 AM »
very nice! I would love a DIY attenuator but I need 40 watts! Does anyone know how to build a Dr Z Brake Lite clone?

Ettore_M

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Re: L-Pad Attenuator
« Reply #7 on: January 09, 2013, 03:13:18 AM »
very nice! I would love a DIY attenuator but I need 40 watts! Does anyone know how to build a Dr Z Brake Lite clone?

I think the Dr Z Brake is based on the Airbrake (the one about alanp posted above).. You'll find it on the net. A little more complicated than the L-Pad attenuator, but it's supposed to sound better...

Hector
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raulduke

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Re: L-Pad Attenuator
« Reply #8 on: January 09, 2013, 03:57:27 AM »
Nice build dude.

I would give it a nice hammertone finish.... but then I would say that wouldn't I  :D

An amp attenuator has been on my 'to do' list for ages now. Thanks for posting the links/info!

pryde

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Re: L-Pad Attenuator
« Reply #9 on: January 09, 2013, 06:54:45 AM »
Nice build. I whipped up a simple LPAD for my 5E3 Tweed and it works great. Used a 3.3uf cap on the attenuator to retain some treble in the signal.

Haberdasher

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Re: L-Pad Attenuator
« Reply #10 on: January 09, 2013, 07:19:39 AM »
I need something like this for my tweaker 15 head.  Thanks for the links sirbw!
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tenwatt

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Re: L-Pad Attenuator
« Reply #11 on: January 09, 2013, 08:11:07 AM »
very nice! I would love a DIY attenuator but I need 40 watts! Does anyone know how to build a Dr Z Brake Lite clone?

Try this:

http://ampgarage.com/forum/viewtopic.php?t=2402&postdays=0&postorder=asc&start=0
Not too bright....

sirbergersworth

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Re: L-Pad Attenuator
« Reply #12 on: January 09, 2013, 02:43:00 PM »
I need something like this for my tweaker 15 head.  Thanks for the links sirbw!

It works fantastic with my tweaker 15.
Just remember that you still have to make sure you have a speaker plugged into the attenuator so you don't blow your amp transformer.
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sirbergersworth

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Re: L-Pad Attenuator
« Reply #13 on: January 09, 2013, 02:44:43 PM »
Nice build dude.

I would give it a nice hammertone finish.... but then I would say that wouldn't I  :D

Thanks for the complement. I think I will do hammertone copper finish with a lawyer clear coat to make it alligator like crazy. Nah, that will take 4 weeks to cure out.
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hammerheadmusicman

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Re: L-Pad Attenuator
« Reply #14 on: January 09, 2013, 03:04:25 PM »
This looks good man! I recently built a DrZ AirBrake for my Maz18, best decision ever, great live to give you more power tube saturation at lower volumes, and the bedroom playing too!

George
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