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Altair - PW-5 Power Attenuator

$75 used

The first power attenuator for guitar amps, before the Scholz Power Soak.

The first guitar amp power attenuator. I examined one in a used guitar store ($75). It has a big switch-knob that turns from 4 to 44 dB attenuation, in 4 dB increments. It is a box smaller than a shoebox, with a light brown metal case. No other controls, just two jacks. The metal casing has holes on all sides except the front, so you can see through it. It's almost empty inside - not much to it at all. There is an inch-wide flat strip that goes lengthwise through the box, with a coiled heater wire wrapped around it. It is tapped at various points. Across the connectors of the switch, there are additional resistive wires -- looks a little sketchy. The heater wire is silver, and difficult to solder to. Sometimes the solder connection fails and the Altair jumps to full power; one user had to regularly re-solder the connection.

auction PW-5

>Do the instructions say anything about what setting to use at a given ohm level? Should you NOT use it... say... on a 16 ohm amp (for example)? Is it safe for any ohm level?

Pete wrote, from the manual:

               From 3.9 to 8 Ohms with a 4 Ohm load
               From 5 to 8 Ohms with a 8 Ohm load
               From 6 to 8 Ohms with a 16 Ohm load

Maximum recommended amplifier power  300 watts into 4 Ohms, 150 watts into 8 Ohms

Max current 15 A
Peak voltage 100 V

>Important is, the first sentence in the tech info section is:

"The PW-5 may be used with any amplifier with an output impedance of 8
ohms or less..."

>So if you can switch that amp to 8 Ohms, that would be a really good
idea.  I gotta get this thing scanned!



SonicVision wrote:

>>Does anyone have any info/experience with the Altair PW-5 power attenuator. I heard one being used on a Marshall plexi Super Lead amp at a guitar show. It sounded pretty good. I'm not sure what the final word is regarding these things in general, are they safe to use or will they screw up the output transformers? I'm not sure what type of attenuation this one uses.

Mark Mitchell wrote:

>I used one of these for many years with my Marshall 50 and used the Line Out to go into a parametric equalizer and power amp. The power amp level was like a big master volume and the equalizer put back a lot of the tone that the Altair sucked. You tend to go through tubes a little quicker but it worked great. And yes, the Marshall was turned up all the way, most of the time.

Randall Aiken wrote:

>I recall seeing a tag [saying do not use with any power attenuator] hanging on a new Marshall a few years back, I haven't seen them on the new amps or the reissue stuff. I believe they quit putting it on when they came out with their own Power Brake, or the SE100 rack mount speaker emulator, which had a 6, 12, and 18 dB switch. I wonder how they suddenly made the amps strong enough to handle the load? :)

>I have used these things since the first Altair power attenuator came out around 1978 or so. I used it on a Fender Twin, a Fender Bassman 50, and a 50 and 100 watt Marshall with no problems. The Altair had a rotary switch that switched in different taps soldered onto a piece of nichrome heater wire. It got nice and toasty, and had a bad habit of coming unsoldered in the middle of a set, resulting in instant full volume! Nichrome wire isn't the easiest thing in the world to solder to. The thing looked pretty cool, though. :)

>After the Altair died one too many times, I got one of the Scholz power soaks, which I still have, and occasionally use with my old 50 watt non-master Marshall. It also doubles as a nice dummy load for working on amps. It is composed of several ceramic body power resistors that can be switched in or out to change the attenuation while (supposedly) keeping a constant impedance load on the amp. I've never verified that, but I've never blown up an amp with it either, so it is probably true.

DejaNews query: altair

Messages 1-66 of exactly 66 matches for search altair:

        Date   Scr        Subject                     Newsgroup           Author
   1. 98/11/13 026 Re: Altair PW-5 Power Attenu alt.guitar.amps       marksmitchell  
   2. 98/11/11 025 Altair PW-5 Power Attenuator alt.guitar.amps       |=>SonicVision<
   3. 98/11/11 024 Re: Altair PW-5 Power Attenu alt.guitar.amps       Bobby Owsinski 
   4. 98/10/28 023 ALTAIR POWER ANNENUATOR      alt.guitar.amps       Mark Griswold  
   5. 98/10/28 022 Re: ALTAIR POWER ANNENUATOR  alt.guitar.amps       Mark Griswold  
   6. 98/10/28 022 Re: ALTAIR POWER ANNENUATOR  alt.guitar.amps       Bobby Owsinski 
   7. 98/10/29 021 Re: ALTAIR POWER ANNENUATOR  alt.guitar.amps       marksmitchell  
   8. 98/10/28 021 Re: ALTAIR POWER ANNENUATOR  alt.guitar.amps       Mark Limbeck   
   9. 98/08/25 020 Altair Tube Limiter          alt.guitar.effects    Bell           
  10. 98/08/15 017 Re: Hot Plate: Bad for amps? alt.guitar.amps       Marc Ferguson  
  11. 98/07/02 017 Re: PowerSoak Question       alt.guitar.amps       Bobby Owsinski 
  12. 98/05/23 017 Re: WOLLMANN THE VULAGARIAN  alt.astrology         Edmond Wollmann
  13. 98/05/23 017 Re: Ricky Ellis THE VULGARIA alt.astrology         Edmond Wollmann
  14. 98/05/22 017 Re: RICKY ELLISTHE VULAGARIA alt.astrology         Edmond Wollmann
  15. 96/07/23 017 FS: Altair Power Soak        rec.music.makers.guit Jack A. Zucker 
  16. 98/10/06 016 Re: Page and Plant Rocks!    alt.guitar.effects    Alan Thompson  
  17. 98/08/29 016 Re: What is Jimmy Page using alt.guitar.effects    Steve Conrad   
  18. 98/05/31 016 Re: Open Letter to Edmond Wo alt.sports.basketball Edmond Wollmann
  19. 98/05/22 016 Re: A public apology to Ann  alt.astrology.scam    Edmond Wollmann
  20. 96/05/17 016 Altair Power attenuator      alt.guitar.amps       Charles C.     
  21. 96/05/17 016 Re: Altair Power attenuator  alt.guitar.amps       Jack A. Zucker 
  22. 98/05/23 015 Re: Goodbye                  alt.astrology         Edmond Wollmann
  23. 98/05/22 015 Re: Defamation was-Re: Gee,  alt.astrology         Edmond Wollmann
  24. 98/05/22 015 Re: Defamation was-Re: Gee,  alt.astrology         Fletcher       
  25. 98/05/22 015 Re: Defamation was-Re: Gee,  alt.astrology         anonym         
  26. 98/04/04 015 Re: thd hot plate...    #3/4 alt.guitar.amps       Steve          
  27. 98/02/06 015 Re: Do Valve amp power soaks alt.guitar.amps       Tyrone Shuz    
  28. 98/01/02 015 Re: Marshall Super Lead Ques alt.guitar.amps       Rich Koerner   
  29. 97/08/20 015 Re: Cranked Amps!            alt.guitar            Jeff Vineburg  
  30. 97/06/18 015 Re: Power Soak               alt.guitar            RutledgeTW     
  31. 97/04/09 015 Re: Power Brake              alt.guitar.amps       Duncan Markley 
  32. 97/04/09 015 Re: Power Brake              alt.guitar.amps       Randall Aiken  
  33. 96/05/18 015 Re: Altair Power attenuator  alt.guitar.amps       Mark Duncan    
  34. 98/02/05 014 Re: Marshall 2000 Head  #2/3 alt.guitar            Steve          
  35. 98/01/13 014 Re: THD Hot Plate or Mar#2/3 alt.guitar            Steve          
  36. 98/01/03 014 Re: Marshall Super Lead Ques alt.guitar.amps       TimTube        
  37. 98/01/03 014 Re: Marshall Super Lead Ques alt.guitar.amps       Peter          
  38. 98/01/02 014 Re: Marshall Super Lead Ques alt.guitar.amps       Peter          
  39. 97/12/07 014 Re: Power Attenuators ..#2/3 alt.guitar.amps       Steve          
  40. 97/09/10 014 Re: Can I build a Power Soak alt.guitar.amps       Jeff Vineburg  
  41. 97/08/08 014 Re: PRS Set neck or Bolt nec rec.music.makers.guit Jay Vyas       
  42. 97/06/18 014 Re: Power Soak               alt.guitar            8Ball, corner p
  43. 97/06/04 014 Re: Will a Power Soak Blow u alt.guitar.amps       Joe Breher     
  44. 97/05/31 014 Re: Power Soak               rec.music.makers.guit Rich Lockyer   
  45. 97/05/16 014 Re: THD HotPlate 8ohm        rec.music.makers.guit Peter Stroud   
  46. 97/05/02 014 Re: Help req with Marshall S alt.guitar.amps       TimTube        
  47. 97/03/07 014 Re: Gear List                rec.music.makers.guit Cypher         
  48. 97/01/30 014 Re: Power soak question      alt.guitar.amps       Gino C. Iorfida
  49. 96/08/14 014 Re: THD Attenuator?          alt.guitar.amps       jaybee         
  50. 96/08/13 014 Re: THD Attenuator?          alt.guitar.amps       Steve Milberger
  51. 96/06/13 014 Re: Whats your rig??? Heres  rec.music.makers.guit M. Diewald     
  52. 97/09/16 013 Re: Opinions wanted: Pow#2/3 alt.guitar.amps       Steve          
  53. 97/09/14 013 Re: Can I build a Power Soak alt.guitar.amps       rich-karl      
  54. 97/06/03 013 Re: Questions From the Mothe alt.algebra.help      Anita Whiting  
  55. 97/05/11 013 Re: Aiken Attenuator/Loa#2/3 alt.guitar.amps       Randall Aiken  
  56. 97/04/18 013 Re: Tuning a guitar---DC Lut alt.guitar            Altair Aerospac
  57. 96/07/15 013 Re: HELP..need to make a spe rec.audio.pro         Gordon Gunn    
  58. 96/01/04 013 Re: Powersoaks THD & Mar#1/2 rec.music.makers.guit jaybee         
  59. 96/01/04 013 Re: Powersoaks THD & Marhsal rec.music.makers.guit Randall Aiken  
  60. 97/03/06 012 Re: Gear List                rec.music.makers.guit Cypher         
  61. 96/10/29 012 Re: Rvw of Power Brake, Hot  alt.guitar.amps       Bobby Owsinski 
  62. 96/08/12 012 Re: THD Attenuator?          alt.guitar.amps       David Fung     
  63. 96/04/06 012 Re: Amps with switchable out alt.guitar.amps       TimTube        
  64. 96/01/04 012 Re: Powersoaks THD & Marhsal rec.music.makers.guit David Roach    
  65. 95/06/13 012 How to connect two humbucker rec.music.makers.guit Lykakis Janis  
  66. 96/12/17 011 Re: Power Tube Distortion    alt.guitar.amps       Randall Aiken  

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