Infinity REF607F Reference Series 6.5 in Coaxial Speakers - Clear

In this review the Infinity REF607F Reference Series 6.5 in coaxial speakers are evaluated as a direct upgrade for drivers wanting clearer highs and stronger bass from a factory system. The single biggest reason to buy is the combination of Infinity's edge-driven textile tweeter and Harman's Plus One cone design, which together produce smooth, non-fatiguing highs and increased low-frequency output; those two traits make these speakers an easy choice for anyone prioritizing sound quality and fitment for common vehicle speaker locations.

Key Features

• Edge-driven textile tweeter: Delivers smooth, clear high frequencies that remain non-fatiguing even at higher listening levels, preserving detail in vocals and cymbals.
• Plus One cone design: Provides more cone surface area than typical cones in this class, resulting in higher sensitivity and stronger low-frequency performance from a 6.5 in driver.
• Tweeter output control: Adjustable tweeter level on larger Reference systems helps tune high-frequency balance to compensate for installation location or personal taste.
• Compact, vehicle-friendly basket: Newly engineered baskets fit most factory speaker locations, making these speakers a straightforward upgrade without major modifications.
• Range of available sizes: The Reference series is offered in many standard sizes so shoppers can find matching speakers for a multi-position install and consistent sound across the car.

Who It's For

The REF607F is aimed at drivers who want a tangible improvement over stock speakers without adding external amplification or complex processing; audiophile-leaning listeners will appreciate the non-fatiguing tweeter and the emphasis on accurate midrange and stronger bass from the Plus One woofer. Installers and DIYers who need a compact speaker that drops into common factory locations will also find the fit and packaging convenient.

Those who need the absolute maximum SPL and extension for professional competition use, or anyone requiring a dedicated two-way component system for custom door panels, should look at larger Reference multielement or component models instead; the coaxial REF607F shines as an accessible, all-in-one upgrade rather than a dedicated high-power competition driver.

Pros & Cons

Pros

• Clear, smooth high-frequency presentation from the edge-driven textile tweeter that reduces listener fatigue.
• Enhanced bass and midrange output thanks to Harman's Plus One cone area, improving perceived loudness and impact.
• Compact basket and common sizing make replacement quicker and reduce fitment issues in most vehicles.

Cons

• As a coaxial design, it cannot match the imaging precision or upgrade flexibility of separate component speakers for audiophile installations.
• Tweeter level control is available on larger Reference multielement systems but not on this 6.5 in coaxial, limiting on-the-fly high-frequency tuning.

Specifications

Model	REF607F Reference Series 6.5 in coaxial
Tweeter type	Edge-driven textile tweeter
Woofer design	Plus One cone (oversized surface area)
Speaker size	6.5 in coaxial
Fitment	Compact baskets for most factory locations
Adjustable tweeter	Available on larger Reference multielement/component models (not on this coaxial)

Our Verdict

The Infinity REF607F 6.5 in coaxial is a sensible, well-rounded upgrade for most drivers who want clearer highs and stronger bass without changing speaker locations or adding amps. It balances refined high-frequency behavior with the Plus One woofer's increased output, offering strong value for anyone replacing worn factory speakers and seeking noticeably better sound.

Frequently Asked Questions

Will these fit standard 6.5 in factory locations?
Yes, the Reference series uses newly engineered compact baskets designed to drop into most 6.5 in factory speaker locations without major modification.

Do these include a tweeter level control?
The coaxial REF607F does not include an external tweeter level control; that feature is offered on larger Reference multielement and component systems.

Are these suitable without an external amplifier?
Yes, the speakers are designed to perform well as a direct upgrade to factory systems and provide improved sensitivity and bass output without requiring added amplification.