MISSION 81-LF170-Q Woofer Speakers Repair 81-LF170/Q 781 6-1/2

( Brand: Mission ), ( Manufacturer Part Number: 81-LF170/Q ), ( Compatible Brand: Universal ), ( Type: Woofer ), ( Size: 6.5 ), ( Country Of Origin: France )

Review MISSION 81-lf170/q 781 6-1/2 Inch Woofer Speakers Ohm Needs Repair

The **Mission 81-LF170/Q (Model 781) 6.5" Woofer Speaker** is a high-performance, full-range driver designed for audiophiles and professional sound systems seeking exceptional clarity, power handling, and durability. Part of Mission Audio s renowned LF series, this woofer is engineered to deliver deep, dynamic bass with remarkable precision while maintaining an impressive frequency response that extends seamlessly into the midrange. Crafted with Mission s signature attention to detail, the 6.5" LF170/Q features a **high-efficiency, high-excursion cone assembly** constructed from **high-modulus, lightweight composite materials**, ensuring minimal distortion even at high SPL levels. The **spun-copper voice coil** is wound on a high-temperature-resistant former, providing outstanding thermal stability and longevity, while the **long-excursion dust cap** enhances linearity and reduces cone breakup at extreme displacements. The **high-mass, high-Q suspension system** is meticulously tuned to optimize both transient response and damping, allowing the woofer to handle significant power inputs (up to **170 watts RMS continuous**) without compromising sound quality. The **large magnetic structure** with a **neodymium ferrite magnet** delivers a robust magnetic field, ensuring consistent performance across a wide frequency range while minimizing distortion. Whether integrated into a high-end home audio system, a car audio setup, or a professional PA application, this woofer excels in reproducing rich, detailed bass with remarkable accuracy, making it a staple choice for discerning listeners who demand nothing less than perfection. Its robust build and reliability also make it a favored component for DIY enthusiasts and audio technicians repairing or upgrading speaker systems.

### Pros and Cons of Buying Used Mission 81-LF170/Q781 6.5" Woofer Speakers

1. **High-Quality Sound Reproduction** These speakers are known for their deep bass response and clear highs, making them suitable for audiophiles and home theater setups. The 6.5" woofer is designed to deliver powerful, accurate bass, which is essential for music and film audio.

2. **Durability and Build Quality** Mission Audio is a well-regarded brand in the audio industry, known for robust construction. The LF170/Q781 series features high-quality materials, including aluminum or steel woofers and reinforced cones, which contribute to longevity.

3. **Versatility** These speakers can be used in various applications, including car audio, home theater systems, and professional sound reinforcement. Their robust design makes them adaptable to different environments.

4. **Aftermarket Support** Mission Audio has a strong reputation for reliability, and replacement parts (such as cones, voice coils, and spiders) are often available. This makes repairs and upgrades easier compared to some lesser-known brands.

5. **Value for Money** Purchasing used speakers can be cost-effective, especially if they are in good condition. For the performance they offer, buying used can save significant money compared to buying new high-end alternatives.

6. **Compatibility with Amplifiers** The LF170/Q781 series is designed to work well with a variety of amplifiers, including high-power units, making them suitable for demanding setups.

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1. **Potential Wear and Tear** Since these are used speakers, they may show signs of aging, such as frayed wires, damaged voice coils, or worn-out cones. This could lead to reduced performance or the need for repairs.

2. **Unknown History** Without access to the speaker s service records, it s difficult to determine if they ve been properly maintained or if they ve been subjected to excessive heat, moisture, or physical damage. This could affect their lifespan.

3. **Repair Costs** While Mission Audio speakers are durable, repairs can be expensive, especially if the issue is with the voice coil or motor assembly. Replacing a voice coil, for example, can cost as much as $100 $200 or more, depending on the part and labor.

4. **Compatibility Issues** If the speakers were previously used in a car audio system, they may have been modified (e.g., with custom voice coils or crossover networks). These modifications might not be compatible with your intended setup, requiring additional adjustments or replacements.

5. **Limited Warranty (If Any)** Used speakers typically come without a warranty. If something goes wrong shortly after purchase, you ll be responsible for the repair costs without recourse.

6. **Potential for Hidden Damage** Issues like internal shorts, damaged magnets, or delamination of the cone can be difficult to detect without a thorough inspection. These problems could lead to failure or poor performance.

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Buying used Mission 81-LF170/Q781 6.5" woofer speakers can be a smart financial decision if you prioritize performance and are willing to invest time in inspecting them thoroughly. Their reputation for quality and durability makes them a strong choice for audiophiles, but the risks of hidden damage or repair costs must be carefully considered. If you re on a budget and can find a well-maintained pair, they offer excellent value. However, if you prefer peace of mind and want to avoid potential repair headaches, purchasing new or certified pre-owned speakers with a warranty might be a safer alternative.

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1. **Inspect Thoroughly** Before purchasing, test the speakers for distortion, uneven bass response, or unusual noises. Check for physical damage to the cones, surrounds, and wiring. If possible, have an audio professional inspect them.

2. **Verify the Condition** Ask the seller for documentation (e.g., service records) or proof that the speakers have been well-maintained. If they ve been used in a car, inquire about any modifications or known issues.

3. **Budget for Repairs** Set aside funds for potential repairs, especially if the speakers show signs of wear. Consider whether the cost of repairs would outweigh the savings of buying used.

4. **Compare with New Alternatives** If your budget allows, compare the cost of repairing or replacing used speakers with the price of new or refurbished Mission Audio speakers (or alternatives like JL Audio, Fane, or Kicker). New speakers often come with warranties and may offer better long-term reliability.

5. **Buy from a Reputable Seller** Purchase from trusted sources like audio forums, reputable dealers, or classifieds with positive reviews. Avoid deals that seem too good to be true, as they may indicate hidden problems.

6. **Consider a Refurbished Option** If available, refurbished Mission speakers (with warranties) strike a balance between cost and reliability. These are often professionally inspected and restored to like-new condition.

**Final Verdict:** If you re confident in your ability to assess the speakers condition and are prepared for potential repairs, buying used Mission 81-LF170/Q781 speakers can be a great way to enhance your audio system without breaking the bank. However, if you value convenience and long-term reliability, investing in new or refurbished speakers may be the better choice.

Details:

Removed from a Mission 781 speaker pair. Both 6.5 woofers were non-working, and upon closer inspection, the wire to speaker coils damaged, probably from leaking ferry-fluid. In the close-up photos you can see green copper corrosion.

part #: 81lf170 price

• $10.00

specifications speakerpartgo:

• brand: Mission
• mpn: 81-lf170/q
• compatible brand: Universal
• type: Woofer
• size: 6.5
• country of origin: France

general speakerpartgo:

• TV, Video Audio Parts > Speaker Parts Components > Other Speaker Parts Comp
• condition: For parts or not working

returns speakerpartgo:

• policy: No Returns

seller speakerpartgo:

• rating: 96.7%
• city: Alexandria, Virginia
• # reviews: 290

payments speakerpartgo:

• other
• credit card: Discover
• wallet: Google-pay

shipping speakerpartgo:

• class: Standard
• cost: $11.23
• transit: 5-11 Days
• carrier: USPS
• type: Calculated
• service: USPS Ground Advantage

offer speakerpartgo:

• options: Ship-to-home
• availability: In Stock
• best offers: True
• started: March 7, 2026
• sold: 0
• quantity: 1

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