[Elecraft] K3s Internal Speaker

[Ron D'Eau Claire]

Hi Steve. Ron (Tech writer) AC7AC here. 

After r/r the speaker in a K3, K3 and K3S many times, I have managed to make
little dimples in the frame ears around the lock washers and nuts. But that
does not damage the performance of the speaker. 

As you probably know, the distortion and buzzing occurs with the voice coil
attached at the center of the cone rubs against the magnet. That happens
when the entire frame is distorted. 

Such distortion can result from aggressively tightening the mounting screws
so that the ring were the voice coil is attached is bent, which is why the
warning in the assembly procedure. But it takes being very aggressive. 

It can happen as a result of handling too, particularly if the speaker is
dropped, even when in its box. The magnet is heavy enough that it can bend
the frame members supporting the magnet on impact. I did that once right on
my workbench. 

It sounds like the factory accidentally may have sent you a defective
speaker, since you obviously are aware of the distortion issue. Or it's
possible the box containing the speaker was the victim of a shipping company
"gorilla" dribbling it across the sorting table. Elecraft packages shipments
very well, but I never underestimate the abilities of shipping companies,
Hi! 

73, Ron AC7AC



-----Original Message-----
From: Elecraft [mailto:elecraft-bounces at mailman.qth.net] On Behalf Of Wayne
Burdick
Sent: Saturday, December 5, 2015 12:11 PM
To: Steve Ellington
Cc: elecraft at mailman.qth.net
Subject: Re: [Elecraft] K3s Internal Speaker

Hi Steve,

Sorry to hear about this. I've never heard this complaint before (and there
are tens of thousands of these speakers in use, in both the K3 and K3S). The
frame should not bend if the correct fibre washers are used and the hardware
is not over-tightened. I'll check with our manufacturing lead to see if the
wrong ones were shipped.

I'll also check with our tech writer. Perhaps the instructions could be
clarified. 

The internal speaker is certainly of high quality, so I hope you can get one
installed (I'm sure customer support will send another, given your issues).
It has excellent sensitivity (95 dB SPL, due in part to the very large
shielded magnet) and a wide frequency response range. Given the large top
cover mounting surface, the internal speaker is quite loud, with a low
natural resonance point.

73,
Wayne
N6KR

On Dec 5, 2015, at 11:59 AM, Steve Ellington <steven4lq at gmail.com> wrote:

> I've made 2 attempts to install a speaker in my new K3s but they bend 
> like butter and distort. I was very careful to use the fiber washers 
> and to not over tighten the bolts. The frame of the speaker can bent with
2 fingers!
> I've never seen such a flimsy speaker.
> 
> I had a brand x speaker in the junk box that worked great but I wanted 
> it to be original especially since the speaker is necessary to hold 
> down the sub receiver's shield. The junk speaker worked fine while I 
> awaited a replacement but the new  replacement did the same. Basically it
is junk.
> I wonder if they washers they sent are too thin?
> 
> I never use the internal speaker anyway but feel like it should at 
> least work.
> 
> Has anyone else noticed this? Otherwise I love the K3s!
> 
> Steve N4LQ



______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft at mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html Message
delivered to ron at elecraft.com