Greets!
Yes, correct.
Have you measured them yet?
FWIW, based on the FF125's 60 Hz Fs, 0.24 Qo published specs and recommended 8 L cab, then Vas would be around 11.52 L. As already discussed though is that time has probably changed their specs somewhat, so curious what each driver measures.
GM
Yes, correct.
Have you measured them yet?
FWIW, based on the FF125's 60 Hz Fs, 0.24 Qo published specs and recommended 8 L cab, then Vas would be around 11.52 L. As already discussed though is that time has probably changed their specs somewhat, so curious what each driver measures.
GM
Anytime someone mentions two per side, I automatically think of the Castle microtower - I've built a total of 3 pairs now, so it's probably clear that I quite like them for smaller drivers.
Small footprint floorstanding MLTL- I like them the most with panel for top firing driver tilted forward at 10dg.
Shown here with Mark Audio CHBW70 and ERT26 tweeters
Small footprint floorstanding MLTL- I like them the most with panel for top firing driver tilted forward at 10dg.
Shown here with Mark Audio CHBW70 and ERT26 tweeters
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Hi Dave.
Unfortunately, the person had only 4. Sorry.
I measured the resonance frequency of one ff125 at 84 hz! It has approximately 12 hours of functioning.
It seems to me high while the specifications indicate 60 hz.
To be sure of my measures, I measured one fe108 ez which has already worked a lot and I obtained 78 hz (77 hz in the specifications).
This ff125 is approximately 30 years old. It had stayed in its original packing. The suspension and the spider had to stiffen ! I am going to run them in free air with a frequency of 5 hz during at least a day, I shall see if it improves.
Meanwhile, I am going to reinstall Speaker Workshop to measure thiele and small completly.
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Hello to all.
I ran 4 ff125 with a variable sinusoidal frequency between 3 and 30 hz during a day.
The resonance frequency fell between 71 and 73 hz for the 4. It is better but still above the specifications.
60 hz adorned me optimist especially for a 12 cm driver. In the specifications of the FF125n (modéle according to) the frequency indicated is 70 hz.
Out of curiosity, I also measured my FE127e, they did not work a lot lately, I obtained 85 HZ!
I also measured my fe103s ACR, and I obtained 100hz! I have the impression that fostex tends a lot to stiffen in time.
I made a mixture of acetone and petroleum jelly.
I applied the mixture to the spider and the suspension of fe103s and I ran them 24 hours.
The resonance frequency then was in + or - 80 hz (79 hz in specifications). It is better tuned in, the bass are deeper and the sound is softer. Enclosure are Suzy Chang.
Anybody has already noticed these problems with Fostex?
I ran 4 ff125 with a variable sinusoidal frequency between 3 and 30 hz during a day.
The resonance frequency fell between 71 and 73 hz for the 4. It is better but still above the specifications.
60 hz adorned me optimist especially for a 12 cm driver. In the specifications of the FF125n (modéle according to) the frequency indicated is 70 hz.
Out of curiosity, I also measured my FE127e, they did not work a lot lately, I obtained 85 HZ!
I also measured my fe103s ACR, and I obtained 100hz! I have the impression that fostex tends a lot to stiffen in time.
I made a mixture of acetone and petroleum jelly.
I applied the mixture to the spider and the suspension of fe103s and I ran them 24 hours.
The resonance frequency then was in + or - 80 hz (79 hz in specifications). It is better tuned in, the bass are deeper and the sound is softer. Enclosure are Suzy Chang.
Anybody has already noticed these problems with Fostex?
It's not specific to fostex. Surrounds and spiders get stiffer when they get old, driving up Fs. If you want an extreme solution, apply some silicone oil to the spiders. Beware that this stuff is horrible for woodworkers though. Use very cautiously. Even microscopic amounts on your workbench can potentially cause finishing problems (fish eyes) later on.
Nevertheless, I have other old drivers who have no this problem. But they are not fullrange. I am going to try the silicone on the spider. Thanks
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