I ran the simulations, and my back of the envelope scaling relations worked. A 0.60x scale Karlsonator will give super high sensitivity of circa 94dB at 2.83v but modest bass extension around 57Hz (-3dB point). a 0.90x H & D and 0.40x W scaled Karlsonator (6in wide x 27.6in high) will give deep 36Hz (-3dB) bass extension but about 88dB sensitivity - and will require a BSC to attenuate the highs to balance the lower bass sensitivity. Not sure how good it will be for deep bass as cone mvovement is limited.
Perhaps a 0.75x and adjusted width to get 1500 cu in box might be a better tradeoff of bass extension and sensitivity? Although 57Hz -3dB gets the kick drums just right and will work for 95% of music to sound rich and full.
Perhaps a 0.75x and adjusted width to get 1500 cu in box might be a better tradeoff of bass extension and sensitivity? Although 57Hz -3dB gets the kick drums just right and will work for 95% of music to sound rich and full.
Attachments
Last edited:
I ran the simulations, and my back of the envelope scaling relations worked. A 0.60x scale Karlsonator will give super high sensitivity of circa 94dB at 2.83v but modest bass extension around 57Hz (-3dB point). a 0.90x H & D and 0.40x W scaled Karlsonator (6in wide x 27.6in high) will give deep 36Hz (-3dB) bass extension but about 88dB sensitivity - and will require a BSC to attenuate the highs to balance the lower bass sensitivity. Not sure how good it will be for deep bass as cone mvovement is limited.
Perhaps a 0.75x and adjusted width to get 1500 cu in box might be a better tradeoff of bass extension and sensitivity? Although 57Hz -3dB gets the kick drums just right and will work for 95% of music to sound rich and full.
Holy mother of speakers...that 94db of 0.60x Karlsonator is simply amazing.I think it is the best choice to make.Losing SPL for a weak low bass seems like a lost cause. That 36HZ bass doesn't look too promising and it comes with only 88db, wasted loudness. 57hz bass at -3db looks nice, if not I could compensate with a subwoofer.I think the 0.60X choice is the way to go even if the boxes will be big.The best trade-off.I can have loud mids with good bass. Thank you very much for playing with both scenarios, I really appreciate it.Once again , the Karlsonator is a great design.🙂
Very nice looking build Mas Penk! Good luck on getting it all buttoned up and playing music! 
Let us know how it works out when you finish.
Let us know how it works out when you finish.
Yes, this is sort of getting into Lowther and other high end, high sensitivity full range driver terrritory, but without the "shout".
I just finished my first-ever DIY speaker--a 0.53 Karlsonator in foam board, with a Dayton PA130-8 driver. The sound is a bit like coming from a tin can. There is bass, but not much treble. I used a few handfuls from the inside of a pillow to stuff it like the photos. Did I mess up, or do I need to give it time?
The PA130-8 is a known good sounding driver in this speaker. It may not have dazzling highs above 12kHz, but that's not what would make it sound like music from a tin can. If you remove the Karlson aperture, does it sound better? If that's the case, maybe slowly enlarge the aperture cutout. Some photos would be helpful to help debug.
@xrk971 Do you have an idea if the Dayton CE65W-8 could be used as driver? It's small, but with a separate sub maybe? I'm curious as it's a very cheap driver (€6,45).
Yes, on the inside area adjacent to the back of the driver, line with foam. Melamine miracle eraser sponges are the best. But thick felt or even grey open cell foam is better than nothing. You want to line any direct line of sight area from the back of the cone.
An example here:
Mini Karlsonator (0.53X) with Dual TC9FD's
An example here:
Mini Karlsonator (0.53X) with Dual TC9FD's
Last edited:
Great, thanks! I didn't do that the first time around. Hopefully, Mr. Clean will erase any unwanted resonances.
On my XKi with 2x PA130-8, the 'boominess' was coming from the front chamber behind the Karlson aperture. I ended up lining the sides and the top section sloping down to the driver with wool carpet underlay. I also put semi circles of underlay behind the wings, directly over the driver. This drastically improved the sound.
If I were to line the closed-end section with thinly sliced melamine, would I still need the pillow stuffing? I know the melamine is to dampen reflections--what is the purpose of the poly-fil?