[Elecraft] K3 Speaker, Season finale

[Wayne Burdick]

As the party responsible for the K3's speaker selection and orientation, I thought I'd weigh in here.

The speaker selected has extremely high sensitivity (95 dB SPL) and excellent audio response, thanks in part to its large (and shielded) magnet. It met our fidelity and drive-level goals for an internal speaker.

The speaker is mounted on the top cover rather than facing forward based on our experiments with the K3 and earlier radios. We tried mounting the same speaker (and others) in an enclosure the same height as the K3, on the front panel. While mid and high-range audio was a little louder in this orientation, bass was significantly weaker. It turns out that response is accentuated by mounting the speaker on the top cover due to enclosure geometry (larger surface area). 

In most home installations the speaker audio is also reflected off the wall or equipment directly behind the radio. This, too, favors a top-mounted speaker.

If you want more audio power and wider response range, you can use two passive (or powered) external speakers. The K3 was designed to drive two passive (non-powered) external 4 to 8-ohm speakers such as the KLH970 to quite high volume levels. These speakers are about 8x4x4" (HWD), so they are indeed taller than the K3, but they're black and nicely styled and look very nice on either side of the radio. I put mine on a shelf above it.

The K3 was designed from the ground up to be full stereo, so I do recommend using two speakers rather than one. This gives you audio effects such as simulated stereo, as well as main/left and sub/right when using the sub receiver.

We may offer our own matching speakers someday, though we have no such project in the works since (in our opinion) the K3's internal speaker does an excellent job. You can also achieve excellent results with two external unpowered speakers that may set you back $20.

73,
Wayne
N6KR