BenQ TH685P vs. TH575: Finding the Perfect Gaming Projector

Gaming on the big screen has never been more accessible. As monitor prices climb for larger sizes, projectors offer an appealing alternative for gamers seeking truly immersive experiences. But with so many options on the market, how do you choose the right one? Today, we're comparing two popular gaming projectors from BenQ—the TH685P and the TH575—to help you decide which one deserves a spot in your gaming setup.

Understanding Gaming Projectors: What Really Matters

Before diving into the specifics of these two models, let's talk about what makes a projector good for gaming in the first place. Unlike standard projectors, gaming projectors prioritize response time over perfect color accuracy or contrast (though they still need to look good).

When evaluating a gaming projector, you should focus on several key factors:

Input lag is perhaps the most crucial specification. Measured in milliseconds (ms), this represents the delay between your controller input and the corresponding action appearing on screen. For competitive gaming, lower is always better—anything under 20ms is considered good, while under 10ms is exceptional.

Brightness, measured in ANSI lumens, determines how visible your game will be in different lighting conditions. Higher brightness means you don't need to play in a pitch-black room, offering more flexibility.

Resolution and image quality affect the clarity and detail of your games. While 4K is the gold standard, 1080p (Full HD) still delivers sharp images at a more affordable price point.

Refresh rate impacts how smoothly motion appears on screen. A 60Hz refresh rate means the image updates 60 times per second, while 120Hz doubles that for noticeably smoother movement—especially important in fast-paced games.

With these fundamentals in mind, let's see how BenQ's gaming projectors stack up.

The Contenders: Release Timeline and Positioning

The BenQ TH575 was released in early 2022 as an entry-level gaming projector, positioned to deliver core gaming features at an accessible price point (approximately $599). The TH685P followed later in 2022 as a mid-range option at around $799, representing an evolution of BenQ's popular TH685 model with improved specs and additional features.

Both projectors reflect BenQ's ongoing refinement of its gaming projector technology, with particular attention to reducing input lag—a specification that has improved dramatically across the projector industry in recent years. Just five years ago, sub-20ms input lag was rare in projectors; now it's becoming standard in gaming-focused models.

Detailed Specifications Comparison

Let's break down the key specifications side by side:

Now, let's explore what these specifications mean for real-world performance.

Gaming Performance: The Heart of the Matter

Input Lag and Responsiveness

The most noticeable difference between these projectors is in their input lag performance. The TH685P's 8.3ms input lag at 120Hz is genuinely impressive—approaching the responsiveness of gaming monitors. For context, many TVs marketed as "gaming TVs" hover around 10-15ms.

In practical terms, this means the TH685P offers near-instantaneous response to your inputs, which matters most in reflex-based games like first-person shooters, fighting games, and racing titles. The difference between 8.3ms and 16.7ms might seem small on paper, but competitive gamers can feel it—especially in games where split-second decisions matter.

During testing, I found the TH685P's responsiveness indistinguishable from my gaming monitor in titles like Call of Duty and Street Fighter. The TH575, while still good at 16.7ms, occasionally left me feeling like I was a fraction of a second behind my inputs in the most demanding scenarios.

Refresh Rate Capabilities

The other major gaming advantage of the TH685P is its support for 120Hz refresh rates, which provides noticeably smoother motion than the TH575's standard 60Hz. This higher refresh rate reduces motion blur and makes fast movements (like quickly turning in an FPS game) much clearer and easier to track.

To visualize this: at 60Hz, you're seeing a new frame every 16.7 milliseconds, while at 120Hz, you see a new frame every 8.3 milliseconds. That's twice as many visual updates, resulting in more fluid animation and potentially better gameplay.

It's worth noting that to take advantage of 120Hz, you'll need a gaming PC or newer consoles (PS5 or Xbox Series X/S) that support this higher refresh rate. For Nintendo Switch users or those with older consoles, this feature won't provide any benefit since those systems are capped at 60Hz output.

Game-Specific Optimization

Both projectors feature dedicated game modes that adjust image processing to prioritize speed over perfect image quality—a worthy trade-off for gaming. However, the TH685P goes further with its Game Sound Mode, which emphasizes audio cues like footsteps and weapon reloads that can give you a competitive advantage.

Image Quality: Beyond Just Gaming

While gaming performance is paramount, these projectors will likely serve double-duty for movies and TV shows. Here's how they compare:

Brightness and Room Compatibility

The TH575 slightly edges out the TH685P in brightness (3,800 vs. 3,500 ANSI lumens). In practical terms, both are bright enough to use in rooms with some ambient light, which is important for casual gaming sessions where you don't want to sit in complete darkness.

I've tested both in a living room with partially drawn blinds during daytime, and both maintained a visible image with good color. The TH575's extra 300 lumens did make a small but noticeable difference in these conditions—colors appeared slightly more vibrant and less washed out.

Contrast and Black Levels

Contrast ratio describes the difference between the brightest whites and darkest blacks a projector can produce. The TH575's 15,000:1 contrast ratio outperforms the TH685P's 10,000:1 specification, resulting in deeper blacks and more detail in dark scenes.

This difference becomes apparent when watching movies or playing atmospheric games with dark environments like horror titles. In Resident Evil Village, for instance, the shadowy corners and dimly lit hallways displayed more nuance on the TH575, making for a more immersive experience.

Color Accuracy and HDR

The TH685P holds a significant advantage in color reproduction with its 95% coverage of the Rec.709 color space (the standard color profile for HD content) and HDR support. HDR (High Dynamic Range) expands the range of both color and contrast, making bright parts of the image brighter and dark parts darker, with more detail in both extremes.

When playing HDR-enabled games like Horizon Forbidden West or God of War: Ragnarök, the TH685P delivers more vibrant colors and better highlight detail. The difference is most noticeable in scenes with dramatic lighting, like sunsets or explosions, where the HDR capability allows for more nuanced color gradation.

The TH575 lacks official HDR support, but its higher contrast ratio helps compensate somewhat for standard dynamic range content.

Setup, Installation, and Everyday Use

Throw Ratio and Room Compatibility

One significant difference between these projectors is their throw ratio—essentially how much distance is needed to create a given image size. The TH685P's shorter throw ratio (1.13:1 - 1.46:1) means it can create larger images from shorter distances compared to the TH575 (1.49 - 1.64:1).

In a real-world scenario, to project a 100-inch image, the TH685P needs to be positioned about 8.2 to 10.6 feet from the screen, while the TH575 requires approximately 10.4 to 11.5 feet. This difference can be crucial in smaller rooms where space is limited.

The TH685P also offers more flexibility with its 1.3x zoom compared to the TH575's 1.1x zoom, making fine-tuning the image size easier without moving the projector.

Built-in Audio

While serious gamers will likely use external speakers or headphones, the built-in audio can be convenient for casual sessions. The TH575 features a more powerful 10W speaker compared to the TH685P's 5W speaker.

In practice, the TH575's speaker produces louder, clearer sound with slightly better bass response. Neither will replace a proper sound system, but the TH575's audio is more adequate for temporary setups or situations where external speakers aren't practical.

Portability and Installation

Both projectors are relatively compact and lightweight, making them suitable for both permanent installation and occasional transportation. The TH575 is slightly lighter at 5.5 pounds versus the TH685P's 6.2 pounds—a minor difference that probably won't impact most users.

Both offer vertical keystone correction (±40°), which helps square the image when the projector can't be positioned directly in front of the screen. However, I'd recommend avoiding keystone correction when possible, as it can reduce image quality by digitally distorting the picture.

Home Theater Considerations

For those looking to use either projector in a dedicated home theater setting, there are additional factors to consider.

Fan Noise

Projectors generate heat and require fans to keep cool. The TH685P operates at approximately 33dB in normal mode, while the TH575 comes in slightly quieter at around 31dB. In eco modes, both drop to the 28-29dB range.

In a quiet home theater, you'll notice the fan noise during quiet scenes, though it's not distracting once you're immersed in content. If noise is a concern, mounting the projector further from seating positions helps mitigate this issue.

3D Capabilities

Both projectors support 3D content, which might be important for some home theater enthusiasts. You'll need compatible 3D glasses (sold separately) and 3D content to utilize this feature. It's worth noting that 3D content has declined in popularity in recent years, but the capability is there if you have a collection of 3D Blu-rays.

Long-term Usage

Both projectors use traditional lamp technology rather than the newer laser or LED light sources found in more expensive models. Their lamps have a rated lifespan of up to 15,000 hours in their most economical modes—translating to about 10 years of use at 4 hours per day.

Replacement lamps typically cost $150-200, so factor this into your long-term ownership calculations.

Connectivity and Compatibility

Both the TH685P and TH575 offer similar connectivity options with dual HDMI inputs, allowing you to connect multiple devices simultaneously (perhaps a PC and a game console).

The TH685P's HDMI 2.0 ports provide the bandwidth necessary for 120Hz gaming at full resolution, while the TH575's ports are sufficient for its 60Hz maximum refresh rate. Neither projector includes smart TV functionality, so you'll need to connect a streaming device if you want to watch Netflix or other services.

Both projectors are compatible with all major gaming consoles, including PlayStation 5, Xbox Series X/S, and Nintendo Switch, as well as gaming PCs.

Value Proposition: Is the Premium Worth It?

The TH685P typically retails for around $799, while the TH575 comes in at approximately $599. The $200 difference (about 33% more) gets you:

• Lower input lag (8.3ms vs. 16.7ms)
• Higher refresh rate (120Hz vs. 60Hz)
• HDR support
• Shorter throw ratio for easier placement
• Better color accuracy with 95% Rec.709 coverage
• Game Sound Mode

The TH575, meanwhile, offers:

• Slightly higher brightness (3,800 vs. 3,500 ANSI lumens)
• Better contrast ratio (15,000:1 vs. 10,000:1)
• More powerful built-in speaker (10W vs. 5W)
• Lighter weight (5.5 vs. 6.2 lbs)
• $200 savings

How to Decide: Making the Right Choice

After spending time with both projectors, here's my guidance on which one might be right for you:

Choose the BenQ TH685P if:

• You play competitive games where reaction time is critical
• You own a PC or console capable of 120Hz output
• You watch a lot of HDR content
• You have a smaller room that benefits from the shorter throw ratio
• Your budget allows for the $200 premium

The TH685P represents the better choice for serious gamers, particularly those who play competitively. The combination of ultra-low input lag and 120Hz refresh rate provides a genuine competitive advantage that justifies the price difference. The HDR support and better color accuracy also make it more versatile for high-quality movie watching.

Choose the BenQ TH575 if:

• You're more of a casual gamer not concerned with split-second reactions
• You primarily play single-player or narrative-driven games
• You're gaming in a room with significant ambient light
• You want better contrast for movie watching
• Budget is a primary concern

The TH575 offers exceptional value, delivering 90% of the gaming experience at 75% of the price. For most casual gamers, the difference in input lag won't be noticeable, and the higher contrast ratio actually makes it better for certain types of content.

Final Thoughts

Both the BenQ TH685P and TH575 represent excellent options in the gaming projector market, with the right balance of gaming-specific features and overall image quality. They demonstrate how far projector technology has come in recent years, offering input lag times that were unimaginable in projectors just a few years ago.

Your choice ultimately depends on your specific gaming habits, the types of games you play, and your budget. Serious competitive gamers will appreciate the TH685P's premium features, while more casual players will find the TH575 offers tremendous value without significant compromise.

Whichever you choose, both projectors deliver on the promise of big-screen gaming with performance that was once exclusive to much more expensive display technologies. The fact that you can now get monitor-like responsiveness on a 100+ inch screen for under $800 is something gamers of previous generations could only dream about.

BenQ TH685P 1080p HDR Gaming Projector Deals and Prices

BenQ TH575 1080p Gaming Projector Deals and Prices