Karlson

[freddi]

here's one of Carl & Wayne's klams from some years ago - I think it may have used a Polk 675 coax with a k-tube on the dome tweeter

An externally hosted image should be here but it was not working when we last tested it.

 

[IG81]

^^^^
Somewhat more Rocket than Klam? They are close cousins anyway. Pretty box in any case.

IG

 

[freddi]

the KR5 Rocket in a way was the first klam - Karlson in 1961 had a letter to Poppe talking about an early 8 inch klam - - I'm guessing in operation the metronome shaped rocket above was rotated and mounted with a bracket to the ceiling rather than firing straight up. IIRC the cutting angles are typically six and twelve degrees for the Rocket style.

 

[thedoc]

Here's the frequency response for my mini Klam. I get a strong peak around 600 Hz which I assume is the resonance of the front chamber. I may change the size of the front chamber to see if I can shift the peak to someplace where its less obnoxious.

 

[freddi]

Karlson's original klams seemed to use ~25 degree angle - I don't know if that would help in a really small unit

 

[thedoc]

Right now I'm using a 40 degree angle. I may try the longer front chamber. That may shift the resonance down lower and get it out of the most critical part of the vocal range.

 

[freddi]

cardboard might work for prototyping. If results seem usable then a wood or perhaps a diagonally sliced pvc pipe with wood wings would make a finished speaker. It might take a homemade miter box to to get a clean slice with pvc pipe. I'd like to hear the Phase 3 klam made out of 3/4" plywood rather than the original flexy particleboard.

 

[thedoc]

What I may do is extend the front of my current test box out with cardboard to see what happens. I like the pvc pipe idea. My power miter saw slices pvc quite nicely

 

[xrk971]

Try foam core instead of card board for prototyping. Works great.

 

[thedoc]

or I could cut off the front chamber build a new one and attach it with pocket screws

 

[freddi]

one thing Carl mentioned was making little driver K tall out of pvc or cardboard tubing - I think the vertically oriented pipes were around 30" tall, driver angled as with regular Ultra-Fidelity type, a 2/3 height slot. I assume there was some sort of back chamber but maybe not - ?

 

[xrk971]

I think Ryani built this? Forget which thread it was in.

 

[danerius]

Karlson interview

Hi. I was googling for more info on the theory of Karlson speakers and found this: John Karlson of Karlson loudspeaker fame speaks - 1964 radio - YouTube No idea if its come oup before but thought Id share in case it hasnt

Regards /Bo

 

[IG81]

Hi. I was googling for more info on the theory of Karlson speakers and found this: John Karlson of Karlson loudspeaker fame speaks - 1964 radio - YouTube No idea if its come oup before but thought Id share in case it hasnt

Regards /Bo

This is freddi's post on YT, originally from Roger Russel's archive I believe. Thanks for putting it up as it may catch a few new viewers from here, it's great to hear these audio old-timers.

IG

 

[freddi]

I put the whole show up on archive.org - Eric Towline is alive and still working in audio and movies http://archive.org/details/HiFI64PROJECTTRY4

 

[thedoc]

Tomorrow I will be making new test boxes for my mini Klams with a longer front chamber and a different venting scheme. I finally found a good use for all the scrap plywood in my shop

 

[thedoc]

Vented Klam for 3 inch drivers. 17 1/2 inches long 7 inches wide and 7 1/2 inches long with 6 inch by 1 inch port running the length of the cabinet

An externally hosted image should be here but it was not working when we last tested it.

 

[xrk971]

Nice Klam! How does it sound?

 

[thedoc]

It actually sounds pretty good and I think it will sound great after some tweaking. I'm noticing much less cone movement than a bass reflex cabinet of the same tuning.

 

[xrk971]

What is the design principle? Is the back cavity and vent a transmission line or more like a reflex vent?