[Elecraft] [KX3] New Product: SPX3 External Speaker

[Robert Morris]

First of all, I want to say thanks to everyone for all the great 
feedback I've been getting on the speaker. Here's are some requested 
features:

1. One stereo channel to speaker driver and another channel to output 
jack (already in first prototype)

2. 12V input (planned is 9-15V, like the KX3)

3. Separate powered (active) and unpowered (passive) speakers
The reasons I've gotten for this is that it would save on the weight of 
and inconvenience of charging a second battery

4. Separate volume controls for the internal speaker driver and the 
output jack
The reason I've gotten for this is that a computer will need the volume 
set separately from the speaker.
Some have stated the computer's software can adjust the gain on the 
input, and that there only needs to be one volume control for the 
speaker driver. I'll need consensus on this from the digital mode folks.

5. USB power output
This would be convenient for those who wish to use their speakers as 
phone chargers.

Things to consider:

A. Making two different speakers substantially increases manufacturing 
costs for the most expensive part; the enclosure. Since most folks will 
be fine with just one speaker, then the lower production numbers of the 
passive speaker would make its per unit cost much higher than the active 
one. However, folks would expect a lower price on the passive one. So, 
I'd have to sell them as pairs to justify manufacturing the passive 
ones, which would mean a higher cost to consumers who only want the 
active one. It would also increase the cost to those who want both 
because of the two different enclosures instead of just one enclosure 
twice.

B. The one issue which would force making both an active and a passive 
speaker is the need stated by some respondents that the active one would 
require a second volume control for the output to the computer for 
digital modes. It would be expensive and time consuming for me to try 
every digital mode software on every operating system, so I need 
confirmation whether this is truly necessary.

C. If a second volume control is not truly necessary, then that 
simplifies things tremendously. I'll wait for consensus on this before 
going into why.

D. A USB power output port is beyond the scope of the speaker's intended 
utility. Also, it would draw down the battery at the cost of 
significantly limiting how long the speaker could be used before needing 
a recharge. Furthermore, the extra hole and port would increase the cost 
while reducing ingress protection. Lastly, there's not much room in the 
small enclosure to accomodate nonessential items.

Thanks and 73,
Robert (AG6ZZ)