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?
(http://img.tapatalk.com/d/13/01/09/a6yjuhyq.jpg)
(http://img.tapatalk.com/d/13/01/09/rutupy2a.jpg)
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
I got the same exact switches the other day! The switches look cool
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?
Quote from: stecykmi on January 09, 2013, 05:35:41 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.
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.
The layout for Ken Fischer's Trainwreck Airbrake is floating around the internet.
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?
Quote from: Stomptown on January 09, 2013, 08:18:14 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?
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
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!
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.
I need something like this for my tweaker 15 head. Thanks for the links sirbw!
Quote from: Stomptown on January 09, 2013, 08:18:14 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?
Try this:
http://ampgarage.com/forum/viewtopic.php?t=2402&postdays=0&postorder=asc&start=0
Quote from: Haberdasher on January 09, 2013, 01:19:39 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.
Quote from: raulduke on January 09, 2013, 09:57:27 AM
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.
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
Quote from: hammerheadmusicman on January 09, 2013, 09:04:25 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
Would you mind supplying any links etc for the Zbrake build? Thanks
of course not..
http://www.andyharrison.net/files/AirbrakeLayout.jpg
that's verified too, by me! mouser part numbers too :)
be careful when you order though, as from mouser UK, the nig resistor didnt come with the clips that you set to certain ohms.. so i had to send for them seperate and pay postage!
George
Quote from: hammerheadmusicman on January 09, 2013, 10:06:25 PM
of course not..
http://www.andyharrison.net/files/AirbrakeLayout.jpg
that's verified too, by me! mouser part numbers too :)
be careful when you order though, as from mouser UK, the nig resistor didnt come with the clips that you set to certain ohms.. so i had to send for them seperate and pay postage!
George
THANK YOU!!!!!!!!!
You're very welcome, glad i can finally be of some service! ;)
i think the parts inc all hardware cost me about £60-70ish from mouser.. a hefty saving on almost £300!!
it is great attenuator. Transparent. Sounds greta with my Z, just like having a post amp volume knob, unlike the old marshall ones which are tone destroyers apparently!
Quote from: hammerheadmusicman on January 09, 2013, 10:06:25 PM
of course not..
http://www.andyharrison.net/files/AirbrakeLayout.jpg
that's verified too, by me! mouser part numbers too :)
be careful when you order though, as from mouser UK, the nig resistor didnt come with the clips that you set to certain ohms.. so i had to send for them seperate and pay postage!
George
gracias amigo !
One thing that the Amp Garage thread mentions about the big power resistor that has taps on it -- you need to LIGHTLY sand the exposed coil, to make sure that the taps make contact. (Apparently there tends to be some coating over it.)
I added an L-pad attenuator to a Valve Jr combo quite some time back. I didn't bother with all that fancy "additional cap" stuff like you guys. ;D
I put mine in the amp chassis (on the back) to make it more like my Univalve. It works quite well, but the taper is somewhat lopsided.
I should also add that I was modding a V1 Valve Jr, which only had a 4-ohm output. So I added a 4-ohm resistor in parallel to bring it down to 8 ohms. It was a monster 20W resistor, by the way. No sense in taking chances. ;D
Here's the info on it:
http://www.forrestwhitesides.com/node/81
(http://www.forrestwhitesides.com/files/up/img/layouts/attenuator_wiring_sm.png)
Here is the amp (which I sold):
(http://i257.photobucket.com/albums/hh218/reverse_engineer/VJ_rebuild/vjmod3.jpg)
(http://i257.photobucket.com/albums/hh218/reverse_engineer/VJ_rebuild/vjmod5.jpg)
This is a great project! I wonder if the switchable bright cap thing would work with my Weber Mini Mass? I never use it because it sounds like a wet blanket over the speakers.
I built an Airbrake a couple of years ago after reading a ton about attenuators. It works well, and was fairly simple to build. Not particularly cheap though, and I honestly decided I like to use pedals and the master volume better.
I just find that it allows me to crank my maz a little more on stage, it wasn't too cheap, but was less t Han a third of the retail!
I would rather build the brake lite. It is good up to 45 or 50 watts and its a bit cheaper. Anyone have any info on how to build one?
No sorry, the airbrake is good up to 100 watts. i think parts would be a lot cheaper on your side of the pond though!
Quote from: hammerheadmusicman on January 09, 2013, 09:04:25 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
do you have a link to the DrZ project you used?
I did post it earlier in this thread, but here it is again :)
http://www.andyharrison.net/files/AirbrakeLayout.jpg
that's all i had..
Quote from: hammerheadmusicman on January 12, 2013, 11:33:19 PM
I did post it earlier in this thread, but here it is again :)
http://www.andyharrison.net/files/AirbrakeLayout.jpg
that's all i had..
whoops. i missed it earlier. thanks!
No worries dude, it's a useful piece of kit! Use min all the time!