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Harrison Labs FMOD Inline Crossover Pair 70 Hz Low Pass RCA

Brand:|Part # 266-252
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 # 266-252

Product Details

Harrison Labs FMOD Inline Crossover Pair 70 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 70 Hz Low Pass RCA
  • BrandHarrison Labs
  • Part Number266-252
  • UPC844632053146
  • 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 70 Hz Low Pass RCA
Harrison Labs FMOD Inline Crossover Pair 70 Hz Low Pass RCA is rated 5.0 out of 5 by 7.
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: 2015-12-15
Rated 5 out of 5 by from Great way to repurpose an old ampI built a passive subwoofer and was not wanting to spend a lot of money on a subwoofer amplifier. These are a great way to use an old Sony amplifier to power my sub project. Great clean sounding filter. My only complaint is they amount of clearance required because the stick out so far from the back of the amp.
Date published: 2015-05-16
Rated 5 out of 5 by from Used with TK2050 amp board for sub xoverI used these in my garage stereo set up by putting these on 2 channels of the TK2050 Class-T Digital Audio Amplifier Board and fed them to some closed enclosure woofer bins with Dayton classic 8" woofers in them and sent a full signal to some Tri Trix speakers in sealed enclosures and have the TriTrix on an Axxess AALC 2-Ch Remote Level Controller for tone control since the TriTrix are more sensitive. Works GREAT!! It was definitely more convenient than a separate sub woofer amp and of course the price of a passive crossover at that low of hz would cost way too much.
Date published: 2014-04-20
Rated 5 out of 5 by from Brings out the BASS!!For years I've tinkered around with bass/bandpass subwoofers only to be disappointed by the muddy sound due to higher frequencies being reproduced. I wanted a sound that rounded out the lowest bass frequencies of the free standing 3-way 12" Klipsch's I'm using without being muddied! Lately my issue has been what to do with unused amps and subs. I'm a man on a budget and these 70 HZ FMODs fit the bill for the kind of bass sound I had been searching for!I'm presently using an older Carver HR752 to drive my system, and an old Sony receiver to drive just the sub with these FMOD's from Parts Express inserted in the inputs to the Sony. I am very impressed with the sound! The sub now produces only the lowest frequencies you can feel, coupled with the Klipsch's I'm using provides me with a very pleasant and loud (enough for me anyway) clear sound for movies and music programming. It's not all about how loud, but how dynamically clear the music is which is why I still employ my Carver. It just sounds good to me.My system may be the "Millenium Falcon" of HT, and now with the FMOD's, it kicks butt until I can afford the entire HT system I need.
Date published: 2012-05-10
Rated 5 out of 5 by from PLUG AND GO!!I have an "old school" HiFonics Thor VII amp. It has no built in crossovers. I bridged the amp mono to run my single MTX T45 Sub. I had voice highs coming thru the sub. I read up on crossovers and came across these. Read reviews on how well they work. So I purchased them to see. I received 2 in the package (only used one due to wiring my amp mono. Other one is a spare). Plugged it in BEFORE the amp and presto!! The highs and mids coming thru were gone!!Very simple. I highly recommend this product.
Date published: 2010-03-04
Date published: 2009-10-26
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Product Q&A

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Harrison Labs FMOD Inline Crossover Pair 70 Hz Low Pass RCA

Hello, I want to boost the bass to compliment/dis-locate Polk RC60i In-Ceiling Speakers (40Hz - 20kHz) for background music; bought a Yamaha YST-FSW050BL2 Subwoofer (35 - 160Hz). Y-splitter from source feeds sub too much treble. Which crossover is best? T

Asked by: tigerninety
Please contact our tech support for more help with this question, or 800-338-0531 x1.
Answered by: MattP
Date published: 2015-12-15

If i use the 70hz for subs...

...what would be recommended in a high pass for my mains? i am running dahlquist dq-12s as mains in a stereo/music only setting. they drop of around the mid 50s (sealed 8" woofers), fed by a 35-ish rms per channel tube amp. the subs are going to be (passives i'm building atm) powered by a tube pre/solid state 2 channel pro amp, signals for both mains and subs out from a dac attached to my computer.
Asked by: m0reilly
my preferred crossover point is between 100 and 125 hz.
Answered by: Nitnub
Date published: 2015-12-15

Fmod slope increase.

If you put 2 in series (ex. 70 hz low pass) does the slope double to 24 db/oct starting at 70 hz ? Thanks, Stan
Asked by: Stan 6969
Stacking these, with an attenuator, would give you 35 Hz Lowpass (according to Harrison Labs website).www-hlabs-com/technical/crossovers/
Answered by: Circuitsoft
Date published: 2016-01-06
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