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CS 7 PROBLEMS

 
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Bazoozoo
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Joined: 14 Jan 2005
Posts: 6
Location: Nova Scotia, Canada

PostPosted: Mon Mar 24, 2008 12:48 pm    Post subject: CS 7 PROBLEMS Reply with quote

My 20+ year old pair of CS7's are really sick. I had recently replaced the T33 with Peerless units and bought a new Yamaha receiver and they sounded absolutely wonderful. The T33's were really dead. Anyway, progressive distortion of the higher frequecies ensued after about 2 months and severe breakthrough of the bass interfering with the mids and highs, one channel a little worse than the other. I guess I was running at fairly high power but the new receiver is rated at 100W per channel and I never cranked it right up. I am assuming that my crossover units have basically died of old age. I plan to open them up but would appreciate any guidance from the experts out there. I did hook up to another amp to rule out the new receiver and they performed equally as bad. Don't know where I'd get new xovers.
Thanks & Happy Easter.
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proffski
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Joined: 22 Aug 2003
Posts: 1297
Location: Tewkesbury UK

PostPosted: Mon Mar 24, 2008 2:45 pm    Post subject: CS7 PROBLEMS Reply with quote

Check Crossovers!
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speakerguru
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Joined: 18 Nov 2005
Posts: 959
Location: Green Hut, Tovil

PostPosted: Fri Mar 28, 2008 9:18 am    Post subject: Re: CS 7 PROBLEMS Reply with quote

Bazoozoo wrote:
I guess I was running at fairly high power but the new receiver is rated at 100W per channel and I never cranked it right up.

Famous last words.... and I bet the volume control doesn't even go up to 11! LOL

Seriously though, "normal" music has a high peak to mean power ratio. It is not difficult (or particularly loud) to clip a 100W amplifier. Those old capacitors may well have broken down on voltage peaks. After 20 years I would change them all. You can check resistors with a simple meter. You can get a software test tone generator and check the response of each XO section at spot frequencies and compare channels. Don't forget to connect loads to the XOs. The speakers will do as loads. As long as you don't test above 2V rms you shouldn't deafen yourself and you won't blow up the tweeters. If the XOs are on a printed circuit board, don't dwell on any one spot with the soldering iron else you'll lift the track. Oh, and don't put beans in you ears Wink
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proffski
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Joined: 22 Aug 2003
Posts: 1297
Location: Tewkesbury UK

PostPosted: Fri Mar 28, 2008 3:53 pm    Post subject: Re: CS 7 PROBLEMS Reply with quote

Beans? Shocked
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I contend that for a nation to try to tax itself into prosperity is like a
man standing in a bucket and trying to lift himself up by the handle.
-Winston Churchill
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speakerguru
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Joined: 18 Nov 2005
Posts: 959
Location: Green Hut, Tovil

PostPosted: Sat Mar 29, 2008 12:06 pm    Post subject: Reply with quote

Nor peas Cool
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thelandlord
Introductory Contributor


Joined: 23 Oct 2008
Posts: 9
Location: Near Bristol, UK

PostPosted: Tue Oct 28, 2008 8:00 pm    Post subject: Re: CS 7 PROBLEMS Reply with quote

proffski wrote:
Beans? Shocked


He's a Pete Seeger fan - you have to make allowances... Wink
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