Dr Z Airbrake

[surfnorthwest]

As many of you know I am no fan of attenuators, all of them I have used at one time or another have disappointed me. That brings me to the Dr Z Airbrake, from what I have been told is this one drastically lowers the volume and does not suck tone, I don't know. Also no need to set the ohm load on it which worries me a bit as is can be used for both a 16, 8, and 4 ohm load.

It is much different than a THD or Weber.

If anyone uses this thing what are your thoughts

[MKB]

This is the design suggested to Dr. Z by Ken Fisher of Trainwreck fame. It's a bit of a departure from many of the current attenuators in that it is a mostly resistive device, it doesn't have any type of speaker impedance emulation at all like the Marshall Power Soak and others. It's also extremely simple in design. Rumor is that it is a very good sounding device, and being Ken Fisher designed it, it very well could be. I haven't tried one but plan to very soon.

As with any attenuator, the less attenuation you use the better. Most of them color the sound quite a bit if you have a big amp attenuated to bedroom levels.

[MKB]

I recently built a copy of the Airbrake, it's fairly easy to find the plans on the internet. It's also cheap to build except for the bedroom volume control, which is an expensive 100W rheostat. I wanted one mainly to kill the power a little on a 2466 so I can get the master up above 5 without killing our cat. 8) It does this very well, I'm fairly happy with it. I also used it at a gig over the weekend and it helped a lot. I plan to build one in my 2X12 cab as soon as I order the parts.

Concerning the impedance settings, both Dr. Z and Ken Fischer claim that you don't have to be too concerned about impedance switching with the unit, but the Dr. Z manual suggests you switch your Marshall to 8 ohms impedance when using the Airbrake with a 16 ohm cab. I used a 16 ohm cab with the Airbrake copy and a 1987 clone head for a 4 hour gig with no issues at all (with the head set to 8 ohms).

[BNS]

Faze that's good to hear. I got the Dr. to install a Brake Lite in my Maz Jr. at the factory. UPS says the amp will arrive at my house on Monday. I am staying home from work that day!

[bluesbrother]

I also really hated attenuators and almost gave up.....
I am really pleased with a koch loadboxII in the 16 ohms version.
No toneloss at all and very transparent.This one can handle 120 watt and if
necessary you can use the built in cooling fan.
Even more simple than the Dr Z airbrake ...only input jacks so no knobs nothing is
in between that could suck tone. Eric clapton once said about circuits in amps : less is better

[JkGriffin]

I recently built a copy of the Airbrake, it's fairly easy to find the plans on the internet. It's also cheap to build except for the bedroom volume control, which is an expensive 100W rheostat. I wanted one mainly to kill the power a little on a 2466 so I can get the master up above 5 without killing our cat. 8) It does this very well, I'm fairly happy with it. I also used it at a gig over the weekend and it helped a lot. I plan to build one in my 2X12 cab as soon as I order the parts.

Concerning the impedance settings, both Dr. Z and Ken Fischer claim that you don't have to be too concerned about impedance switching with the unit, but the Dr. Z manual suggests you switch your Marshall to 8 ohms impedance when using the Airbrake with a 16 ohm cab. I used a 16 ohm cab with the Airbrake copy and a 1987 clone head for a 4 hour gig with no issues at all (with the head set to 8 ohms).

Sorry for reviving an anchient post here, but...
You seem to know more than average about this Airbrake which is the one I use as well. I've been using this with my Lil' Elvis to be able to crank it... As far as I've heard I can, while having the airbrake in between, have the head on 16ohm and the cab is 16ohm. When I measure the resistance I do measure from 7.9 to 11ohm. I haven't damaged anything (yet), but I am thinking that maybe I should have had the head at 8ohm. The impedance that the head sees is probably that of the airbrake?

Also, since my JCM800 have no MV, I am thinking of using the airbrake with this amp instead... This is a Canadian model which have only 4 and 8ohm outputs... and I want to use it with 2 of 4 off 12" speakers in the cabinet which is 8ohm. So I assume 8ohm out of head into airbrake and 8ohm speaker will be just great... or?

[kissfanps]

Me thinks i need an attenuator for my new tweed twin. I can't get any break up without cranking it. I was thinking about the brake lite, but I am not sure if its enough. Any thoughts?

[surlybastard]

If you get a chance to try a few out that would be ideal. I've got a Weber MASS Lite which is the speaker motor style of attenuation. I like it, but it's all I've ever used so I can't really compare it to anything else. Like all of them I find Attenuating the least amount possible (or a couple of notches from it) is about all it's good for, after that it ruins your tone and isn't worth using. I bring it with me to wherever I go as I play with different people. Some like it loud, some don't so I try to accommodate. Mainly I find with my VM I use it when I run the amp on LDR because I like to run the Master wide open with the gains up fairly high and just use the volume knob. On LDR I run the attenuation on the minimum just to take the edge off for everyone (I personally don't care about volume because I wear plugs). Typically I can find a volume level on the HDR as I don't run it as high (I prefer a tighter sound in that setting) that everyone can be happy with without using the Weber

[TubeStack]

It's worth pointing out that the AirBrake is advertised as "one size fits all" by Dr Z , ohm-wise, but it's really optimized for 8 ohm use. I found this to be true in my own experiences, as well as reading it in a lot of places.

[surlybastard]

My Weber is the same, there's no way to set the impedance it's just plug and play.

[surfnorthwest]

Tue Dec 02, 2008 9:28 pm

This is a pretty old thread that got dug up. For the record attenuators suck.

[surlybastard]

This is a pretty old thread that got dug up. For the record attenuators suck.

Generally speaking ya, I wish it wasn't necessary. I keep mine only to be considerate to others I play with. I do play with one group of people where volume is no object, that's definitely the most fun