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Philco 38-690 tweeter improvement
#6

How do you have the treble/bandwidth control set? You need wide bandwidth to get high frequencies.

What are you using for source material? If your listening to just AM broadcast stations the tweeters will not see much use because most AM broadcast stations these days have very limited frequency response. Their frequency response does not go much past 5 kHz. Back in the day AM broadcast stations went to 10 KHz or more. In the case of WLW in the late 50's and into the 60's 20+ KHz.

If you really want to hear what your 690 can do build a SSTran AM transmitter. http://www.sstran.com/index.html

I built one for my father and he has a 37-690. With good source material the tweeters are noticeable.

Keep in mind a paper tweeter will never perform like a horn, dome or ribbon tweeter as they will roll off big time on the top end. I would guess they are good to 10-15 kHz.

edit: Ron I missed your post as I was working on mine at the time. I agree the tweeters get kind of bright with the bandwidth set full wide on my fathers 37-690. Any chance of popping the tweeters by dropping the crossover point down to 4000 hz on Dave's 38-690?

Bill

It's not what you don't know that hurts you it's what you know that's not so.


Messages In This Thread
Re: Philco 38-690 tweeter improvement - by Syl - 07-25-2008, 11:16 AM
Re: Philco 38-690 tweeter improvement - by Syl - 07-25-2008, 09:19 PM
[No subject] - by Ron Ramirez - 07-25-2008, 10:39 PM
[No subject] - by wonderwrench - 07-25-2008, 10:52 PM
[No subject] - by Ron Ramirez - 07-25-2008, 11:49 PM
[No subject] - by Dave Slusarczyk - 07-25-2008, 11:53 PM
[No subject] - by wonderwrench - 07-26-2008, 12:06 AM
[No subject] - by Ron Ramirez - 07-26-2008, 12:06 AM
[No subject] - by Ron Ramirez - 07-26-2008, 12:13 AM
[No subject] - by Dave Slusarczyk - 07-26-2008, 12:59 AM
[No subject] - by BDM - 07-26-2008, 01:40 AM
[No subject] - by wonderwrench - 07-26-2008, 01:48 AM
[No subject] - by wonderwrench - 07-26-2008, 02:30 AM
[No subject] - by Syl - 07-26-2008, 09:33 AM
[No subject] - by Ron Ramirez - 07-26-2008, 10:20 AM
[No subject] - by Syl - 07-26-2008, 12:52 PM
[No subject] - by Dave Slusarczyk - 07-26-2008, 04:33 PM
[No subject] - by wonderwrench - 07-26-2008, 04:47 PM
[No subject] - by wonderwrench - 07-26-2008, 04:53 PM
[No subject] - by Ron Ramirez - 07-26-2008, 05:40 PM
[No subject] - by Syl - 07-26-2008, 05:51 PM
[No subject] - by Syl - 07-26-2008, 05:55 PM
[No subject] - by Dave Slusarczyk - 07-26-2008, 06:50 PM
[No subject] - by Syl - 07-26-2008, 08:17 PM
[No subject] - by Dave Slusarczyk - 07-26-2008, 10:26 PM
[No subject] - by Syl - 07-27-2008, 12:11 AM
[No subject] - by Dave Slusarczyk - 07-27-2008, 02:02 PM
[No subject] - by Terry Judkins - 07-27-2008, 06:59 PM
[No subject] - by wonderwrench - 07-27-2008, 07:11 PM
[No subject] - by Dave Slusarczyk - 07-27-2008, 07:53 PM
[No subject] - by wonderwrench - 07-27-2008, 10:00 PM
[No subject] - by Syl - 07-28-2008, 11:21 AM
[No subject] - by Dave Slusarczyk - 07-28-2008, 06:10 PM
[No subject] - by BDM - 07-28-2008, 06:17 PM
[No subject] - by Ron Ramirez - 07-28-2008, 06:59 PM
[No subject] - by Dave Slusarczyk - 07-28-2008, 07:12 PM
[No subject] - by Syl - 07-28-2008, 09:33 PM



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