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Thread: Anyone ever used an In-Line High Pass Filter? |
    
Gold Member Username: Edster922
Abubala,
Ababala
The Occupation
Post Number: 2566
Registered: Mar-05
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| Posted on Friday, October 14, 2005 - 01:00 am: |
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http://www.crutchfield.com/S-4QD1AAde9qk/cgi-bin/ProdView.asp?g=82600&id=essenti al_info&i=069900074#Tab
I think Jan recommended something like this (unfortunately I just can't find the original thread with the link) as an alternative to this:
http://www.hsustore.com/high-pass.html
I did a Google search and found some conflicting opinions as to whether a 12db reduction (identical on both the $28 F-Mod and the $100 Hsu, funny enough) makes any significant difference. Some were saying that when measured it was more like a 6db reduction on the HPFs.
A few people on other forums suggested cascading the F-Mods to get a 24db roll-off, though at the expense of maybe 3-4db in sensitivity.
Just wondering if anyone has ever used these things. I originally started looking at them for my truck, since I bought a cheap Pioneer amp that doesn't have a HPF and this $30 might be better than reselling it and buying an amp that has its own adjustable HPF.
But now am wondering if I can use it between my CDP and receiver at home, or if it'd only be usable with my NAD separates? |
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Gold Member Username: Edster922
Abubala,
Ababala
The Occupation
Post Number: 2567
Registered: Mar-05
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| Posted on Friday, October 14, 2005 - 01:07 am: |
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also was wondering if this one, which costs 3 times more, would be worth it:
http://www.crutchfield.com/S-4QD1AAde9qk/cgi-bin/ProdView.asp?g=82600&id=essenti al_info&i=20603KX2#Tab
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Gold Member Username: Jan_b_vigne
Dallas,
TX
Post Number: 6140
Registered: May-04
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| Posted on Friday, October 14, 2005 - 10:27 am: |
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Whatja actually trying to do with it, ed?
The Fmods are an inexpensive way to get a job done. They are not absolutely accurate as far as roll off nor specific frequency for the action. I've ordered an adjustable unit to begin my experiments with this DIY subwoofer. I haven't received the Adire driver yet, so I can't tell you about the actual quality of the Fmods but one reviewer from The Absolute Sound considers them a usable, if not very good, choice for bi and tri amping a system. I found them through T8's web site and asked him about using them. He still uses them in limited applications with his preference (if I can speaker for Tim) being an active Xo (at a substantially higher price) with more control over what is happening with the signal.
It's again a bit of a trade off between a passive device which will add no noise but is not the most accurate way to get the job done. On the other hand, the active device gives you more control at the expense of more circuitry and therefore more noise and distortion product. A very good active Xo is a better way to do the job than either of your options but is going to follow the general rule of very good = very expensive.
In a car system, I can't imagine why the Fmods wouldn't be a decent solution unless you are very critical of your car system. (Check out the Harrison Labs web site.) Look at what the active unit gives you (for the price it may not be any more accurate or useful than the Fmods) and decide if it is worth the money. The Fmod with the adjustable frequency is worth using over a fixed device IMO. Get them direct from the manufacturer off eBay.
http://www.hlabs.com/technical/crossovers/
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Gold Member Username: Edster922
Abubala,
Ababala
The Occupation
Post Number: 2576
Registered: Mar-05
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| Posted on Friday, October 14, 2005 - 10:55 pm: |
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The reason I'm looking at these F-Mods is because I am accursed with these lousy 80Hz crossover points in my Panny at home and my Pioneer HU in the truck, and both my home and car speakers roll off at 50Hz so I certainly don't want to miss that 30Hz in between. If I decide to keep the NAD separates in my bedroom I might want to add some F-Mods there too, but first I have to buy some decent speakers for that system.
I've done a search on eBay for the F-mods but no luck. Parts Express has them for $3 cheaper than Crutchfield though.
What I wonder is, what would happen if I connected one of these F-Mods to my analog cable between the CDP and receiver? Does it only work with a separate amp? |
Gold Member Username: Edster922
Abubala,
Ababala
The Occupation
Post Number: 2577
Registered: Mar-05
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| Posted on Saturday, October 15, 2005 - 12:56 am: |
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oh never mind, just found HL on eBay. Geez, they charge more than even Crutchfield!
God bless Parts Express! |
Gold Member Username: Edster922
Abubala,
Ababala
The Occupation
Post Number: 2581
Registered: Mar-05
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| Posted on Saturday, October 15, 2005 - 12:33 pm: |
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bump (the forum software isn't showing new replies on the section list for some reason) |
Gold Member Username: Edster922
Abubala,
Ababala
The Occupation
Post Number: 2582
Registered: Mar-05
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| Posted on Saturday, October 15, 2005 - 12:33 pm: |
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bump (the forum software isn't showing new replies on the section list for some reason) --- "Internal Server Error" keeps popping up after I hit "post this message" |
Gold Member Username: Edster922
Abubala,
Ababala
The Occupation
Post Number: 2583
Registered: Mar-05
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| Posted on Saturday, October 15, 2005 - 12:36 pm: |
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bump (the forum software isn't showing new replies on the section list for some reason) --- "Internal Server Error" keeps popping up after I hit "post this message" |
