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1 Page 1 of 10 START NEW THREAD REPLY Top of Thread LIST Read 383 times Date: 8/18/2001 2:52 PM ATTENUATORS Has anyone compared the Hotplate, Airbrake and Powerbrake attenuators? I use to own a Powerbrake but foolishly sold it with my 100 watt marshalls thinking my homebrew 50's wouldn't need it. So now I need attenuation but not sure which of the three are the most transparent. db Read 363 times Greg (MusicWard@aol.com) Date: 8/18/2001 6:50 PM Of the 3 you mentioned I would compare the Airbrake and the Hotplate and forget about the Powerbrake. I own a Komet Airbrake and up to 3 clicks its the most transparent attenuator I've heard IMHO. Good luck Greg Read 350 times Date: 8/18/2001 8:34 PM Thanks for the reply Greg, what kinda amp/cab ya using? Read 349 times Lee (lmholbrook@mindspring.com) Date: 8/18/2001 8:51 PM

2 Page 2 of 10 Hey Guys: I have an old Altair PW5 and an old Scholz attenuator. I use 'em with BF Fender's and my Marshall JCM800 50W & 100W amps. I have very good ears for tone, and I've never noticed that they color the sound at all. What is it I should be hearing? Perhaps I'm missing something. I was very careful with both at first, because I had heard bad things about them blowing tranny's a lot, but with speaker imps matched correctly to output, I have never had a problem with them, and I really push 'em hard. Plus, they actually make my $hitty sounding $ovtek EL34's sound good. Without the attenuation, the $hiteks sound just like $... (I'm sure y'all know this, though) When I'm burning good quality power tubes, (Siemans, NOS 6CA4's etc) the attenuators allow the amps to sound even better, without the ear splitting volume. (Of course, when I play gigs outside, the Marshalls are set on "Full Stun" because we know nothing else would do!) No offense meant by my post, I just wonder if I am missing something, or I maybe got a couple of rare "good quality" attenuators here??? Rock On! Lee Read 344 times John Kelley Brown (ledboots@home.com) Date: 8/18/ :08 PM I had the Altair, I bought it new along with a new 100 watt Hiwatt back in 1978, within 2 months I had to replace a transformer, I had to wait 5 months for the Partridge transformer to arrive from England, there were no impedance missmatches with the 4x12 Hiwatt cab. But I never had problems with the Sholtz Powersoak. The Hot plate was a very noticable improvement over the Powersoak and the Airbreak is a slightly noticable improvement over the Hot Plate. I only played through the Powerbreak once, it was with a BF Bandmaster head, it sounded like crap, real raspy. So, of all these the Airbreak is the best according to my ears. Soon I want to try the M.A.S.S. speaker motor from Weber, this requires building the circuit around the M.A.S.S., but I don't need to take on any new projects at this time, so I can't give a critique. Kelley Read 291 times Date: 8/19/2001 3:03 PM John, what is M.A.S.S.? Yeah your right, the powerbrake is somewhat raspy especially in the lower settings down. You mentioned the airbrake sounding somewhat better than the hotplate,is it a cleaner sound? thanks db

3 Page 3 of 10 Read 282 times Mark H. (mark999@cybernex.net) Date: 8/19/2001 3:20 PM Mass is Webers coneless speaker, developed for use as a reactive load for power attenuators & such. They're still in the development stage for a speaker emulator design, but you can buy the mass "motor" if you want to design something yourself. Mark Read 280 times Date: 8/19/2001 3:29 PM cool idea, anyone try this? db Read 288 times Mark H. (mark999@cybernex.net) Date: 8/19/2001 3:36 PM I haven't seen any posts about it, but I ordered one last Friday to replace the purely resistive load that I'm

4 Page 4 of 10 currently using. Don't know what the sonic results will be, but hey it was only fourty bucks Mark Read 275 times Date: 8/19/2001 4:02 PM yeah,if it sounds good for that price! Read 263 times Greg (MusicWard@aol.com) Date: 8/19/2001 5:03 PM David Im using a Komet head with various cabs: 4x12 Marshall w/greenies 2x12 with Blues 2x12 w/pre Rola G12H30s Greg Read 272 times Date: 8/19/2001 5:29 PM Nice rig! never had 30's,they alot different than 25's? Kinda cautious about using the Airbrake with my homebrew cuz at the Komet site they say safe operation with Komet amps ONLY! db

5 Page 5 of 10 Read 257 times hogy Date: 8/19/2001 9:22 PM David, that's not what it says on the Komet website. Here's the quote: "The Airbrake will work with other manufacturer s amplifiers, but Komet Amplification, L.L.C. guarantees safe operation with Komet amplifiers only." The important word is "guarantees". It simply means that if our Airbrake damages your KOMET in any way, we'll fix it for free. The Airbrake has been around for a very long time, long before the Hotplate, I believe? Ken Fischer's been making them since the early eighties, originally for use with Trainwrecks, but people used them with Marshalls, Voxes, Fenders, etc. Neither Ken nor I have ever heard of a single amp being damaged by an Airbrake in almost 20 years. The Komet's been around for less than two years, so obviously most Airbrakes have been used with amps other than the Komet. I'm just not going to go out on a limb and guarantee it, not knowing the type and condition of the amp it's going to be used with. Actually, the condition wouldn't even matter, since the Airbrake doesn't stress either the tubes or the output transformer more that playing straight into a speaker, but somebody is bound to use it with a rusted up, waterlogged, undersized, 40 year old transformer that would have died anyway, and blame us when it finally goes. That's what I'm trying to avoid. When chosing an attenuator, there are only 2 aspects that matter: 1. Is it safe for the amp? 2. Do you like the sound of it? If can answer both questions with "yes", you've found it. Resistive, reactive, active, hyperactive, distractive, who cares? Hogy Read 158 times Date: 8/20/2001 1:12 PM Thanks Hogy, I see your point and agree, just fussy about my newest homebrew!now there's that rebate check haha BTW nice looking and sounding amps! db Read 272 times Ed DeGenaro (ed@thdelectronics.com) Date: 8/19/2001 5:31 PM

6 Page 6 of 10 This might be a silly question, but aren't all the attenuators out there...airbrake, Muzzle, etc...designed with reactive loads? I mean ours is, and just assumed all the stuff that came after would be too. Ed DeGenaro THD Electronics, Ltd. Read 271 times Mark H. (mark999@cybernex.net) Date: 8/19/2001 6:06 PM No, not silly, I mistakenly used the term "reactive load" too vaguely. But how do you describe the mass thing, "mechano-reactive"? Transducer without a cause"? Mark Read 242 times steve b Date: 8/19/2001 8:42 PM I believe aron,over at the effects forum uses the mass.give him a shout and ask him about it and how to wire it up. Read 226 times aron (aronnelson@bigfoot.com) Date: 8/19/ :15 PM Ed, First of all no. Not all attenuators out there are "reactive". In fact, I, like most people, thought that a reactive attenuator _would_ be best. In fact, I have found, that again - like

7 Page 7 of 10 everything in electronics - it depends on the circuit. The Airbrake is NOT reactive. It is purely resistive, yet it sounds great. The MASS speaker system I think is great. I use em on my amps and it delivers a good tone. NO, it is not the same as without it, but it works very well. Possibly as good or better than most solutions out there. Aron Read 127 times Ed DeGenaro (ed@thdelectronics.com) Date: 8/20/2001 4:00 PM Aron I suppose the reason I thought the Airbrake was reactive was becuase of its line-out function. I've been using a Hotplate to load down heads, and if you believe Bob Bradshaw it's the "amp can't sound perfect without a reactive load" thing. But I looked into it and realised that I was just making an assumption. And yes all things being equal an amp will be more happy seeing a reactive load. Ed Read 234 times John Kelley Brown (kelbrown@cisco.com) Date: 8/19/ :44 PM David, I like both the Hot Plate and the Airbreak. I don't think when cranking up an amp and then attenuating it down that the player is really looking for a cleaner tone, but if you mean a more transparent tone preserving the distortion qualities of the cranked amp without the attenuator mucking things up, then I would say this. The Hot Plate and the Airbreak both sound about as good when attenuating a little bit, as you start to attenuate a little more, to my ears anyway, the Airbreak is a little more transparent. But heres the thing, you need the speaker(s) to move air and add distortion qualities of it's own, when you start to attenuate down to the point where the speaker can't lend it's magic to the tone, say the output of a 10 watt amp, (which is still loud), the tone starts to suffer. I don't think even the most revolutionary attenuator could compenate for that. Kelley Read 172 times

8 Page 8 of 10 Date: 8/20/2001 1:24 PM Yes John transparent is the word I was looking for loud! For my use I just wanna set it a couple notches to tame it down so as not to drowned out the band! even a 50 watter is too thanks db Read 163 times Tom-Andrew (e97_tos@e.kth.se) Date: 8/20/2001 2:16 PM Since we're talking attenuation... I'm wondering what you guys think of the plug-in things, like the Ruby Tone-Bones/THD Yellow Jackets, exchanging the output tubes to EL84's? Anyone tried them?! I'm thinking of getting a pair of Tone-Bones or Yellow Jackets for my Laney VC50. The Laney is by the way going to be sold, so I can buy a Marshall 1987 from What do you think about the plug-ins in a 1987?! Would I be better off buying an attenuator? Thanks! /Tom-Andrew Read 126 times Ed DeGenaro (ed@thdelectronics.com) Date: 8/20/2001 4:12 PM

9 Page 9 of 10 I've been using Yellow Jackets in a 74 Super Lead 100 watter. And also load it down to slave it into efx and the power section of a 50 watter. The sound is Marshall meets Vox, output drops by about half. And twith a Strat sounds reminiscent to the first Scott Henderson Blues album. In terms of tone, not that I could play like him. Ed Read 144 times John Kelley Brown (ledboots@home.com) Date: 8/20/2001 3:35 PM David, Either the Hot Plate or the Airbreak will suit you fine for the uses you are describing. Both will sound great attenuating a 50 watt amp down to the output of say, a Vox AC30, the Airbreak will start sounding better than the Hot Plate attenuating the amp down to Fender SF/BF Deluxe levels then start to suffer at about the output level of a Fender Princeton, to attenuate more than that where the speaker can't give anything, even the Airbreak will not sound good. Kelley Read 154 times anonymous Date: 8/20/2001 3:46 PM Kelley made a great point about the speakers you use. It makes sense to try a different cabinet with fewer and lower capacity speakers. Also, when you get whatever you buy, experiment with it as a parallel load. 3dB may be all you need to drop. Then switching to a less efficient cabinet may bring it down to just the right place. I had a drummer complain about my volume being a bit low with a cranked 18watt amp. With the same guy, a 50W marshall was too loud. I switched to the 50 Watt marshall with a parallel load, into a 1-12" open back V30. That seemed to hit just the right level (that day). Read 7 times Doug H (dhammond@nospam_cfl.rr.com) Date: 3:33 PM Soon I want to try the M.A.S.S. speaker motor from Weber, this requires building the circuit around the M.A.S.S., but I don't need to take on any new projects at this

10 Page 10 of 10 time, so I can't give a critique. For just doing attenuation, the ckt is pretty simple: a 100 ohm/2w resistor and 100 ohm/1w pot in a divider parallel to the Mass. They have the example ckt at the Weber site. The main trick, as I understand it from Aron, is isolating the motor (in a box with some foam or etc) so you don't hear it, as it will vibrate and produce sound. If you're building a "speaker emulator" for line-level recording, you will need to do more work with filtering and so forth. My Mass is being shipped today. I've got a 5W wirewound pot and a power resistor waiting to be wired up.;-) I'll be glad to give my opinions after I get it set up, if anyone's still interested. In my case I've got a little 10W amp and I'm trying to push the 6L6 without disturbing everyone in my house. Doug alternate display for printing