BenQ TH671ST Review

The BenQ TH671ST is the budget entry point to the BenQ golf simulator projector lineup. At around $950, it costs $150–$200 less than laser alternatives while delivering the same 1080p resolution, comparable throw ratio, and the same 16.67ms input lag. The trade-off is a lamp light source instead of laser — which means eventual lamp replacement and a brightness that will gradually diminish with use. For a first simulator build where budget matters, it's the right choice. For a permanent installation where you don't want to think about maintenance, spend a little more for laser.

Key specifications

Throw ratio — slightly different from 0.5 models

The TH671ST's throw ratio of 0.69–0.83 is notably different from the LH820ST and GT2000HDR's ~0.50. That difference matters for placement. At 0.69, a 10 ft wide screen needs about 7 ft of throw distance. At 0.83, it needs closer to 8.3 ft. A 12 ft screen needs 8.3–10 ft. This means you need more separation between the projector and the screen than with the tighter-throw models.

In a 20 ft room, this is no problem — you have plenty of room to position the projector at 8–10 ft from the screen while keeping the hitting position safely in between. In a 14–16 ft room, the geometry gets tighter and the 0.69 end of the range may be needed to keep everything fitting. The 1.2× optical zoom gives some flexibility — you can dial in the image size without physically moving the projector, which is particularly useful during initial setup.

The practical implication: if your room is 14 ft or shorter from screen to back wall, the GT2000HDR or LH820ST's ~0.50 throw ratio is a better fit. If you have 16+ ft, the TH671ST works well.

Brightness and image quality

At 3,000 lumens, the TH671ST is bright enough for a dedicated room with controlled lighting, and workable in a garage with the door closed and modest overhead lighting. It's 500–600 lumens below the GT2000HDR and LH820ST — noticeable in direct comparison, less noticeable when you're playing. In a well-controlled dark room you won't care about the brightness difference. In a room with some ambient light, the GT2000HDR will look better.

The 92% Rec. 709 coverage is actually slightly higher than the LH820ST's 90%, which means accurate colour reproduction across the course palette. Course greens and blues look natural and well-saturated on properly configured simulator software. The TH671ST doesn't have BenQ's Golf Mode, but the core colour accuracy is strong enough that it's not missed in practice.

The lamp trade-off — what it means in practice

Lamp projectors are not bad projectors. The TH671ST's lamp delivers good brightness and colour for the first several hundred hours of use. The issue is what happens over time.

In Normal mode, the lamp is rated at 4,000 hours before it reaches 50% brightness. That's roughly 5 years at 2 hours per day — but you'll notice the dimming well before the rated end of life. SmartEco mode extends this significantly: 10,000 hours at the cost of some brightness reduction. LampSave mode pushes to 15,000 hours with a more significant brightness reduction. Most simulator users run SmartEco, accepting a modest brightness reduction in exchange for much longer lamp life.

When the lamp eventually fails or becomes too dim, replacement lamps cost around $50–$100. It's not a difficult replacement, but it does require dismounting the projector if ceiling-mounted. For most users, this happens once every 5–10 years of regular use in SmartEco mode — not a huge burden, but a consideration for a permanent installation.

Who should buy the TH671ST

This is the right projector if you're building your first simulator and want to keep total cost under control. At $950, it saves $100–$200 vs the GT2000HDR and delivers a genuinely good 1080p simulator image. The throw ratio works fine in rooms 16 ft deep or more. The lamp trade-off is a real consideration for permanent installs but perfectly acceptable for a first build.

It's not the right choice if your room is under 14 ft deep (the throw ratio is too loose for very short rooms), if your garage is particularly dusty (no IP5X sealing), or if you know you're building a permanent dedicated space and want zero maintenance friction.

Verdict

The TH671ST earns its place as the best-value entry in the golf simulator projector market. The image quality, input lag, and throw ratio are all competitive. The lamp light source is an honest trade-off for the price. If your budget is tight and your room works with the 0.69–0.83 throw ratio, this is the right projector.

Frequently asked questions

TH671ST vs GT2000HDR — which is worth the extra money? For most permanent installs: the GT2000HDR. Laser reliability, HDR support, and no lamp replacement are worth $100–$200 for a projector that will be mounted permanently and used regularly. For a budget-first first build: the TH671ST is perfectly capable and the money is better spent elsewhere in the system.

Does the TH671ST work with simulator software? Yes — it connects via HDMI 1.4a and is compatible with GSPro, E6 Connect, TGC 2019, Creative Golf, and all other major platforms. The HDMI 1.4a input limits you to 1080p at 60Hz, which is fine for simulator use.

How long will the lamp last in a golf simulator? In SmartEco mode at 2 hours per session, 3 sessions per week: roughly 6–7 years before brightness noticeably degrades. In LampSave mode: potentially 10+ years. In Normal mode: 3–4 years.

Can I ceiling mount it? Yes. Use a standard ceiling projector mount with the appropriate adapter — BenQ sells compatible mounts, as do third-party brands. The 1.2× optical zoom gives useful flexibility for fine-tuning image size without repositioning the mount.