Buchardt A500 評測：可下潛至 25 Hz 的緊湊型書架喇叭

引言

Buchardt A500 是一款緊湊型書架喇叭，但背負著異常進取的使命。其箱體前方裝有一枚 6 吋低音單元及一枚 3/4 吋半球形高音單元，背面另有一枚 6 吋低音單元；載入合適的調校後，它在無響室條件下量測平坦，在室內更可下潛至 25 Hz。對這個體積的喇叭而言，這是相當認真的數字。

定價約為 3,500 EUR，折合約 4,100 USD。Buchardt 亦另行發售一款無線 hub，可接受 HDMI、光纖、同軸、USB 音訊及模擬 RCA 訊源，然後以無線方式將訊號傳送至每隻喇叭。這款 hub 正是解鎖應用程式 EQ 與房間校正的關鍵，也是將一對 A500 變成完整系統的一環。

Buchardt A500 適合哪些人

這款喇叭針對的是想要一套細小、高質素系統、又不想擺放一堆獨立器材的聆聽者。它會回報任何願意花時間處理均衡的人。應用程式允許手動調整，而 hub 可執行房間校正程序，播放粉紅噪音並利用手機內置麥克風識別房間模態，然後著手將其撫平。喜歡將系統調校至配合自己房間的聆聽者，會從中獲得极大樂趣。

它對極大型房間，或任何想在四米或更遠距離以高音量聆聽的人來說，則不太自然契合。在該情況下，A500 會觸及其自身保護限制，此時更安全的調校加上超低音喇叭會是更明智的路線。主要追求任何距離下最大輸出的人，應在決定前仔細衡量這些取捨。

主要優勢

The A500 gets the fundamentals right. Its on-axis response stays linear to within about plus or minus 1 dB, and the listening window and early reflections track that on-axis response closely, which means the sound arriving directly and the sound reflecting off the room share a similar tonal character. That consistency also means the speaker responds predictably to equalization, so adjustments in the app behave the way you would expect them to.

高音單元與波導設計

The 3/4-inch dome tweeter sits in a large waveguide, and the design is more clever than the small dome suggests. The flare of the waveguide is steeper close to the tweeter and opens up further out, which raises sensitivity at the bottom of the tweeter’s range and allows a lower crossover point, while still controlling dispersion at higher frequencies. In effect the design behaves partly like a horn at low frequencies and partly like a waveguide higher up.

The practical payoff is controlled horizontal dispersion of roughly plus or minus 50 degrees, which is enough to give the speaker a convincing sense of width and room involvement. The trade-off appears in the vertical plane, where there is some lobing above and below the tweeter, but that sits outside the plus or minus 10 degree vertical window most listeners occupy, which makes it a reasonable compromise.

平坦響應與輸出能力

Bass extension is the headline. With the correct tuning the A500 reaches down to 25 Hz, and it does so while staying flat rather than simply adding a hump. That extension comes with a caveat. The lower you push the response, the more output capability you give up, and the built-in DSP applies hard limiting to the woofer to protect it. Measured distortion reaches roughly 3 percent THD around 80 Hz at 86 dB, which is acceptable for a cabinet this size.

In practice the speaker handles normal listening well. A pair reached around 103 to 105 dB at three meters without mechanical noise or audible distortion, and that was near the point where pushing further stopped making sense. For most rooms and most music, that is more than enough headroom.

購買前需考慮的事項

The A500 is not a speaker for every room or every listener. Off-axis behavior includes a resonance around 600 Hz in the horizontal response, which becomes more noticeable beyond roughly 50 degrees off axis. The estimated in-room response also carries a slight upward trend that can sound bright in rooms with hard, reflective surfaces, though the speaker takes equalization well enough that this is straightforward to address.

Output limits deserve attention as well. Hard limiting on the woofer is present from 76 to 86 dB and increases at 96 dB and 102 dB, with additional limiting in the mid band and through the tweeter. None of that was audible at normal levels with a pair in a room, but it is a genuine consideration for anyone planning long listening distances or very dynamic material.

房間互動與無線 hub

The hub is not optional in practice if you want the full experience. It is a separate purchase, currently around 300 USD on sale with a regular price closer to 500 USD, and it is what enables app-based equalization, the room correction routine, and the ability to switch between the roughly 11 master tunings Buchardt offers. Those tunings, loaded from a USB stick into the back of the speaker, include the theoretical new setting, theoretical standard, theoretical all-around new, a warm profile and a neutral high pass 60 Hz option. They change both tonal balance and output capability, so there is plenty of room to find a profile that suits your room.

購買建議

For anyone already considering the A500, the hub should be part of the plan rather than an afterthought. Saving a little longer to include it makes far more sense than running the speakers without it, because so much of what the A500 can do lives in the app and in the master tunings. It is the difference between a good speaker and a system that adapts to your room.

If you listen from roughly four meters or more, or you favor very high volumes and wide dynamic swings, choose a tuning that protects the drivers and add a subwoofer rather than pushing the A500 harder on its own. The high pass tunings exist precisely for that kind of setup, and they let the speaker play to its strengths while a subwoofer handles the low end.

In a treated room at moderate distances, though, the A500 is a genuinely impressive compact speaker. The combination of flat response, deep bass for the size, and flexible tuning makes it easy to recommend within its intended use case.

總結

The Buchardt A500 delivers on a difficult brief. It is a small speaker that measures flat down to 25 Hz with the right tuning, controls its dispersion well through a thoughtfully designed waveguide, and responds beautifully to equalization. Add the wireless hub and it becomes a flexible, room-aware system rather than a passive pair of boxes.

The caveats are real but specific: output limits, a bright-leaning in-room estimate in untreated rooms, and vertical lobing outside the main listening window. Buyers who understand those trade-offs and who plan for the hub will find a compact speaker that performs well beyond what its size suggests.