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Altair power attenuator?

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10/2/2000 1:45 PM
LOU	Altair power attenuator? Hello all, Is this a safe Power Attenuator to use with my Marshall JMP800 50 watt head. Have not used this yet but I need feed back on this thing. Thanks Cheers Lou

10/2/2000 1:48 PM
LOU	Re: Altair power attenuator?Sorry thats a JCM800 Thats a JCM800 50w head.

10/3/2000 6:45 PM

Hi:
I have used good attenuators for several years on many different amps and never had a problem if certain criteria were followed. I've been using an Altair PW5 and a Sholtz Soak for about a year now with my JCM800 50W & 100W heads without any problems. Most good guitar amp designs can take the extra push, but there are some that are not designed well enough for this type of abuse, either. I think the Marshall amp is a very well designed amp and can really be pushed in several ways "IF" one is sure to get the impedence values checked and properly set by a competent tech, etc "BEFORE" you turn the amp on and push the amp. This way with the correct resistence dialed on the imp.selector on the head(s) and the speakers being used, and the correct setting if the attenuator has this type of selector, there should be no mis-matching and no real problems.

I've come up with the idea over the years and after reading many posts and replys that most people who have blown up amps with power attenuators either had them hooked up wrong to begin with, did not have the proper impedence(s) matched from the amp output to speakers, maybe had a bad transformer and/or parts in the amp and the extra strain pushed it over the edge, simply did not know what they were doing, or some of all of the above.

There are many others here who can post helpfully here!

Good Tone & Good Rockin!
Lee

10/4/2000 12:51 PM
LOU	Thanks for the responce Lee. I'll have the impedence values checked out before I Crank it up. Cheers Lou

10/6/2000 2:31 AM
Lee	PS Lou: If you ever decide to sell your ALtair, let me know. If it's a PW5 and it is in good shape I'd do it in a minute! Keep rockin'! Lee

10/8/2000 12:10 AM

Re: Altair power attenuator?

Lou,

The Altair attenuator was absolutely nortorious for blowing up the Marshalls they were used with back when they first came out in the mid-to-late 70s. Personally, I wouldn't touch one with a ten-foot pole! Try The Airbrake designed by Ken Fischer and made by Komet Amplification in Baton Rogue, LA. Their attenuator sounds very good and is designed for either 8 or 16 ohm impedance loads. I wouldn't want to see your JCM800 go up in smoke, you know?
That JCM800 might be worth something soon with this crazy market for amps? Spare yourself the grief in advance.

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