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Harrison Labs FMOD Inline Crossover Pair 50 Hz Low Pass RCA

Brand:|Part # 266-250
FMODs™ feature a 12 dB per octave crossover slope and are compatible with all RCA type input amps. Sold in pairs.
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Part # 266-250

Product Details

Harrison Labs FMOD Inline Crossover Pair 50 Hz Low Pass RCA

What is an FMOD™? The FMOD™ is an active crossover simulator. It is better than a much more expensive electronic crossover that requires power to operate. FMODs™ are packaged in pairs and can be combined with other FMODs™ to obtain bandpass ranges or with other types of crossovers to change the slope and crossover frequency point. FMODs™ feature a 12 dB per octave crossover slope and are compatible with all RCA type input amps...simply place the FMOD™ in-line with the patch cable running between the source (head unit) and the amplifier. 24kt gold over brass construction, 10 volts maximum RMS input. One-year manfacturer warranty. Made in the U.S.A.

Product Specifications
  • Crossover TypeLow Pass
  • ConfigurationInline Line Level
Harrison Labs FMOD Inline Crossover Pair 50 Hz Low Pass RCA
  • BrandHarrison Labs
  • Part Number266-250
  • UPC844632053139
  • Product CategoryIn-Line Crossovers
  • Unit of MeasurePR
  • Product Rating
    (7 Reviews)
  • Weight0.0908 lbs.
  • California Prop 65

    Warning: California residents only. Please note per Proposition 65 that this product may contain chemicals known to the State of California to cause cancer and birth defects or other reproductive harm.

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Harrison Labs FMOD Inline Crossover Pair 50 Hz Low Pass RCA
Harrison Labs FMOD Inline Crossover Pair 50 Hz Low Pass RCA is rated 4.2857 out of 5 by 7.
Rated 1 out of 5 by from DON'T waste your time or moneyThese cut the total signal so much as to be useless, I suggest getting a real crossover.
Date published: 2015-12-29
Rated 5 out of 5 by from Best electronic/passive crossovers for the money!I've bought many sets of FMODs over the past 10 years or so, and for $12 each they are amazing for filtering out unwanted frequencies from subwoofers, midrange, and tweeters. Most of the FMODs I've bought have been low pass crossovers. In most cases they're less expensive than a good quality low pass passive crossover which reduces the amount of power going to the sub(s). And usually you only need to use one FMOD with a home or car car audio audio system, since you only need a mono sub pre-out from your receiver going to the amplifier then to the sub(s). If you want or need to to use stereo left and right inputs to your amplifier you can buy a $2 RCA Y-splitter, and use only 1 FMOD instead of 2 FMODs ($25), even if you are using multiple subs, unless a mono signal will not work. They do a great job at filtering out high frequencies, you can use 2 FMODs with a inexpensive RCA 3 dB attenuator in line between each FMOD to give you a 24 dB/octave slope. You can also change the frequency point by using 2 FMODs together which have different frequencies points. The Harrison Labs website explains how to use 2 FMODs, or different crossover types to create different bandpass ranges for your midrange speakers, different crossover slopes, and different crossover frequency points. I've bought many passive crossovers in the past and wish I had never wasted my money. For about the same money as a single FMOD ($12), in most cases you'll only be able to buy a good qualiy single passive 1st order 6dB/octave crossover. I cannot say enough good things about FMODs because they are so easy to use, and work so well for very little money. I am constantly using FMODs in every stereo system in my home, usually with an older receiver that does not have a built in crossover, or with a mini amplifier that doesn't have a built in crossover, and sometimes in my car (if my amplifier does not have a built in crossover). FMOD crossovers are an absolutely amazing product, one of the best on Parts Express. I tell all of my friends and family about how well FMOD crossovers work, they're high quality, and inexpensive price.
Date published: 2015-12-16
Rated 5 out of 5 by from Works as advertisedHave the 50Hz low pass on my sub. The gradual slope makes the sub blend well with the main speakers, IMO. Let me clear up one mystery: these are directional. There is some debate whether these are directional or not, and they are. Flipping them over and plugging them in to the preamp output changed the sound quality negatively. The male side should face down stream at the end of your interconnects.
Date published: 2015-03-24
Rated 5 out of 5 by from WorksBought the 50’s and 70’s – taking out the honkieness from my added subwoofer on my car. Though tough the amp had a low-pass, it was preset at 120Hz, way too high allowing too much mid bass. Went with the 50’s – much happier now.
Date published: 2013-12-09
Rated 5 out of 5 by from Great productGood price and fast shipping. will buy again.
Date published: 2009-08-19
Rated 5 out of 5 by from These are a MUST OWN for anyone with bass shakers!Since these come as a pair, I doubled them up and now they do an amazing job at filtering out all the unwanted shake during movies. After installing these I can crank up the bass shakers and now they only come on during the high tension/ high action parts of movies. 5 STAR Product all around and 5 star service from Parts Express!
Date published: 2009-02-23
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Product Q&A

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Harrison Labs FMOD Inline Crossover Pair 50 Hz Low Pass RCA

Sorry if this has already been answered elsewhere... But does it have to be between the head unit and the amp or can it be placed between the amp and the speaker?

Asked by: Dilip
This is a line level filter that goes between the source and the amplifier.
Answered by: MattP
Date published: 2016-01-06

I currently have the 50Hz low pass on my subs. If I add 50Hz high pass on my mains, will that create a smooth crossover? Or should I try 30Hz high pass? Do the high pass ones affect the sound at all? I don't want to decrease the clarity of my system.

Asked by: KBob
The actual effect will really depend on the speakers in room response, but I think I would go with the 50 Hz high pass over the 30 Hz, I usually try and keep the crossover points consistent.
Answered by: Chrisf
Date published: 2015-04-02

How are these oriented?  Does it matter?  Is the input the female end, and the output the male end?  Or the other way around?  I may need a gender changer depending on how this hooks up.

Asked by: compaudiopro
In my experience the orientation matters. They are directional. Input is female end so that they are on the end of the interconnects going to the subwoofer amp. I tried flipping them over and plugging them to the output of my pre but that destroyed the soundstage and degraded the sound quality due to too much hf going to the sub.
Answered by: KBob
Date published: 2015-03-24

How does it work using them with a 1-to-2 Y-cable?

If I use a mono-to-stereo RCA cable and put one FMOD each on the L/R stereo ends, is that the same as stacking 2 end-to-end, doubling the slope to 24dB/octave? Thanks in advance!
Asked by: SamH
Unfortunately no, the FMODs much be stacked in order for the slope to increase.
Answered by: MattP
Date published: 2013-06-11

if i use 2 f mods 50hrz low pass together will it now become 25hrz?

Asked by: raymondeast
No, I believe 1 F-Mod has a 12db per Octave slope, if you use 2, it will still be 50hz, but it will be at a 24db per Octave slope.
Answered by: Rickskal
Date published: 2014-12-29
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