Interesting. Mine is better, of course. 😀 It's similar enough that I would expect some of the same benefits. The front chamber seems a little large compared to the rear. All the kluged sims at the time seemed to indicate it would be better to go in the opposite direction, with a smaller volume front chamber. I'm still not sold on the curved reflector. 😉
Hi X,
Just wanted to mention that the 0.53x mini-K's w/ Vifa TC9FD drivers are doing an amazing job in our theater rehearsal area! We have theater camp for 8 to 14 yr olds last week & this week...and those little speakers are getting a good work out. Still don't understand how they can make as much SPL as they do, even in bass freqs.
I have been careful to use controls on the Mackie power amp (capable of delivering 300 wpc into 8 ohms, so probably able to do 450 wpc into 6 ohms) to prevent the kids from releasing the magic smoke.
Cheers, Jim
Just wanted to mention that the 0.53x mini-K's w/ Vifa TC9FD drivers are doing an amazing job in our theater rehearsal area! We have theater camp for 8 to 14 yr olds last week & this week...and those little speakers are getting a good work out. Still don't understand how they can make as much SPL as they do, even in bass freqs.
I have been careful to use controls on the Mackie power amp (capable of delivering 300 wpc into 8 ohms, so probably able to do 450 wpc into 6 ohms) to prevent the kids from releasing the magic smoke.
Cheers, Jim
Jim,
Thanks for the feedback! It's a nice feeling to know that these things are putting a smile on your face. 🙂 There was thread a while ago where someone wanted to make speakers for the dart room in his bar. He had a budget of $50 and I recommended these. The idea was poo poo'd by some folks as "never having enough SPL" for large space like a bar. Oh well... Now I know they can do light duty as PA speakers. They reach deep due to GregB's excellent design which I just figured out how to scale. The K-aperture has a big impact on how big they sound.
Thanks again for the kind words.
X
Thanks for the feedback! It's a nice feeling to know that these things are putting a smile on your face. 🙂 There was thread a while ago where someone wanted to make speakers for the dart room in his bar. He had a budget of $50 and I recommended these. The idea was poo poo'd by some folks as "never having enough SPL" for large space like a bar. Oh well... Now I know they can do light duty as PA speakers. They reach deep due to GregB's excellent design which I just figured out how to scale. The K-aperture has a big impact on how big they sound.
Thanks again for the kind words.
X
do you think this new build by thejessman will look good in two tone with dark for the body and natural for the wings? - its only got 1 cubic foot rear chamber before driver displacement so hope there's a stuffing to get qtc in an OK region
https://fbcdn-sphotos-f-a.akamaihd....883_756913747688446_4776318032976429501_n.jpg
https://fbcdn-sphotos-f-a.akamaihd....883_756913747688446_4776318032976429501_n.jpg
I like the two tone look with natural color wings. Nice box - I have never heard a Klam before wonder what they are like? Are you putting Beta 12LT in it? I have never hear a K15 before either. Need to get me one or build one, although I am pretty happy with my new PRV tops and a bass horn sub.
Last edited:
I'll probably run it with a standard `99dB sensitivity Eminence coax with 80oz magnet and a compression driver with very little if any attenuation - 12LTA might work if the back chamber isn't too small - a thin plywood bracket mounted over the front of the baffle could hold a compression driver with extended K-tube
typical K-tube exit
An externally hosted image should be here but it was not working when we last tested it.
typical K-tube exit
An externally hosted image should be here but it was not working when we last tested it.
Cool! Let's not forget to thank John Karlson for coming up with the simple expedient of a variable width slot. Essentially, it makes a bandpass enclosure into a full bandwidth radiator with reasonably smooth response. (depending on who you ask... 😀😱🙄)
I thought I would try my hand at making a pair of wooden K’s. The drivers were rescued from some Sony plastic boxes. Not knowing any specs on them I made 3 foam core models and then went from there. After quite a bit of adjusting the filling they are sounding pretty good; a hell of a lot better than the plastic boxes. 🙂
Next will be a pair built with some better drivers.
Next will be a pair built with some better drivers.
Attachments
Thanks X- the drivers are an oval 2x3". They have a fairly substantial magnet so I figured they would be reasonably decent. The box is 9.5 x 5.5 x 5.5. I really don't have a clue as to how to figure out what size to make these things. It's fun anyway.
hi prezden - those look real good and the size is great - must be one of the smallest K made so far
I don't quite understand the science behind the Karlson aperture. Anyone mind sharing their knowledge?
There are a couple of things at least that the K aperture provides: a non-distinct boundary condition so that a 1/4-wave doesn't "know" where the edge of the TL mouth is and hence has a smoother response. This can be done by drilling varying degrees of holes towards the terminus of a TL; and the edge provides an acoustic lens for the HF to diffract and spread over a wider angle with more uniform directivity. A Karlson aperture makes the speaker sound more spacious and increases the sweet spot.
when one doesn't have access to fullrange or quality coaxial drivers, a K-tube for treble is one way to go. Subjectively, it may outpoint a CD waveguide or horn and can be made from paper for quick evaluation. I've tried to emphasize the K-tube's use for over a decade
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Last edited:
Thanks freddi- I think I would make them a little taller if I were to do them again. Anyway they sound pretty good so I'm happy with them.
Last edited:
Vintage speaker calculation
Hi xrk971,
I have a pair of 12 inch burman xp5012 speakers, pulled from a guitar amp, that I'm interested in making a Karlson or TL enclosure for. These speakers are 50 watts at 15 ohms. I have been researching and I think they were made by Goodmans. They seem related to the Goodmans audiom 12p-d. Attached is some specs. When you have time, can you do some calculation for me to figure the dimensions for Karlson and TL(and the length of the TL)? Thanks for your help.
Hi xrk971,
I have a pair of 12 inch burman xp5012 speakers, pulled from a guitar amp, that I'm interested in making a Karlson or TL enclosure for. These speakers are 50 watts at 15 ohms. I have been researching and I think they were made by Goodmans. They seem related to the Goodmans audiom 12p-d. Attached is some specs. When you have time, can you do some calculation for me to figure the dimensions for Karlson and TL(and the length of the TL)? Thanks for your help.
