Bottlehead Forum
Bottlehead Kits => Legacy Kit Products => Topic started by: kohked on July 10, 2013, 01:48:51 PM
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All,
I've been working from my "home office" lately (the living room) and sit just a few feet from one of my S8's. The tweeter domes are mashed in a bit, and I was wondering how they actually *sound*. So....I ran my Paraglow's to them directly and as expected, they sound like crap. Some noodling around here in the Bottlehead galaxy has the FedEx man dropping off ST324 tweeters at the gate. After looking at the two little boxes for a week, out comes the router and in go the new tweeters.
Understand that I didn't modify the existing (latest version) crossover at all; just wired in the new tweeters and surface mounted them. Am I wrong to think these sound GREAT!? Maybe I got used to the crappy old ones, but I'm hearing air and sound and nuance I haven't heard in a long time. I play them non-stop just to confirm they sound so good. I'm really happy I did this.
I suppose I'm wondering though....what's the acoustic result of these tweeters with the original crossover? They seem *louder*, but overall I'm really happy and not inclined at the moment to build a new X-over. Should I bother?
best,
Dennis
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Very cool
I have a pair to put into my Straight 8's. One of the many projects I have.
Deb
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Deb,
You really need a router to enlarge the existing hole...but after that it's only about an hour (tops) to do this job.
best,
Dennis
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Yeah look at the relatively recent thread on this. The woofer crossover should stay the same. The tweeter crossover should be a single cap, but I do not recall the value. It's in the thread. The dome tweeter crossover is not optimal for the slot tweeter.
And yeah, it's way better than the old dome tweeter.
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Deb,
You really need a router to enlarge the existing hole...but after that it's only about an hour (tops) to do this job.
best,
Dennis
Never used a router, it will be a good oppertunity to get one and learn how to use it!
Deb
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The value of the cap is .6 i got that from Paul J.It somehow sets the level.
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That value will get you in the ballpark, but it can be worthwhile trying other values nearby as well. Bigger cap - more treble.
Search the threads for much more detail, including the Climax design which was the best we ever did with that tweeter (also - of course - the many mechanical mods).
The tweeter has a peak around 3200Hz. It rolls off at 6dB/octave above there, and 8dB/octave below. By itself it's a fairly crappy tweeter! But a single-cap highpass at 20kHz changes that to flat 3200Hz-20kHz and -24dB/octave below 3200 - a classic 4th order Linkwitz-Riley response.
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Rather than spend a fortune in capacitors buy some inexpensive metalized PP film caps. Find the value then buy a nice one to match your findings.