oh right. I was curious about the curved double mini Karlson in #4335 as a center for a pair of upright 0.53 Karlsonators.
Among the Karlsonator builders, is there a preferred 0.53 driver? My hunch is the PA130's bass will be my prefernce, but curious about the collective impressiosn of the benefits of the options.
Among the Karlsonator builders, is there a preferred 0.53 driver? My hunch is the PA130's bass will be my prefernce, but curious about the collective impressiosn of the benefits of the options.
- single PA130-8
- dual TC9FD18-08
- dual 3FE25-8
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When using two drivers in parallel, it's advisable to use the 16 Ohm versions for a total impedance of 8 Ohm.
I'd vote for FaitalPro's. I've been listening to mine every day for the past 7 years and I'm very happy with them. If bass is a concern, I use a sub.
Definitely build an identical second, otherwise you won't have proper stereo. These speakers excel in making a great soundstage.
Build another set with different drivers if you want to know what it sounds like.
Build another set with different drivers if you want to know what it sounds like.
Enjoying the pair. Initial impressions.
I checked the resistance of the 3FE25 drivers; they’re reading 12 instead of 16 ohms, with 6.2 ohms at the speaker terminals. Is that common? 12 seems pretty far off.
I’ve only screwed the front baffles in place. I may glue them in place since I believe I’m hearing some resonance when I’m pushing them a little bit with Daniel Villareal’s Sunset Cliffs.
I’m about ~7’ away from the speakers with an average of about 70db, hearing a wide and dynamic range easily getting down to 50hz. I’m impressed with the little Faital Pro drivers, and I’m excited to hear the difference between these and the larger Dayton drivers.
I checked the resistance of the 3FE25 drivers; they’re reading 12 instead of 16 ohms, with 6.2 ohms at the speaker terminals. Is that common? 12 seems pretty far off.
I’ve only screwed the front baffles in place. I may glue them in place since I believe I’m hearing some resonance when I’m pushing them a little bit with Daniel Villareal’s Sunset Cliffs.
I’m about ~7’ away from the speakers with an average of about 70db, hearing a wide and dynamic range easily getting down to 50hz. I’m impressed with the little Faital Pro drivers, and I’m excited to hear the difference between these and the larger Dayton drivers.
6.2 Ohms is also what I measure on mine for two drivers in parallel.
Glad that you like the sound. Give them some time. The sound improves gradually as they break in. After 7 years, mine sound sublime. After using my set as main speakers in the living room for several years, they're now doing duty as PC speakers mounted on brackets on the wall, about 1.2m apart. As nearfield speakers they are perfect.
What amp are you driving yours with?
Glad that you like the sound. Give them some time. The sound improves gradually as they break in. After 7 years, mine sound sublime. After using my set as main speakers in the living room for several years, they're now doing duty as PC speakers mounted on brackets on the wall, about 1.2m apart. As nearfield speakers they are perfect.
What amp are you driving yours with?
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The 3FE25-16 DCR is about 12ohms according to the factory graph so I think that’s fine. The 16ohm is a nominal rating for AC music signals.
I recently built some approximately 0.53x Karlsonators around a cheap AliExpress full-range driver (sold as "AIYIMA 2Pcs 5.25 Inch Full Range Speaker Unit 4 8 Ohm 40W Audio Speaker Aluminum Basin Home Audio Amplifier Loudspeaker" for about $40 USD with free shipping at the time I ordered them (during the end of year sales last year). They are the ones with the black paper cones and pink/red whizzers. I've bought a few other cheap Aiyima brand drivers from AliExpress in the past and they have reliably been average to good (although presumably as with everything on that platform some of them are the actual brand and others are unrelated products that just steal the name to sound more credible).
Before starting the build, I sent xrk971 a PM asking for them to be simulated but was advised despite the higher VAS than the drivers usually used for these, they should work. He asked me to post in the thread in future, which was always my intention once the build was done and I could comment on the drivers.
Anyway, I can recommend these drivers for anyone wanting to do a cheap build - they measure fairly flat from 100Hz to 10kHz with an approx 5dB hump centred around about 100Hz. Subjectively they sound quite good - similar to some Frugel Horn XLs I built around some similarly sized Mark Audio drivers previously, but obviously without going as low. There is a subtle 'boxy' sound which I understand is probably related to the wood construction (see below) but I'm also probably overly sensitive to this because a lot of my listening is on open baffle stuff. However voices sound very natural. They've ended up fairly efficient too - no measurements of this, and I'm using them nearfield, but they can get louder than I'd ever want them with barely visible cone excursion, and apparently these drivers reportedly have a 10mm Xmax so presumably they could be pushed a fair bit further.
See attached picture of the finished speakers. I built them out of a mix of solid timber (side panels, front lens, top panel - ranging from about 12-15mm thickness) and 12mm hardwood plywood (everything else). They are very close to the dimensions from the plans for the 0.53x dual TC9FD version from the start of this thread - I believe I ended up about 10mm shorter and 5mm shallower due to the wood I had to hand. Stuffing was mostly as per XRK's instructions elsewhere in this thread (to help remove 'boxiness' in a wooden build) - primarily melamine sponges everywhere that faces the driver and foamcore on the back of the len, although I also put some 1/2" felt above the sponges about half way up the back cavity + on the back of the top panel, which may or may not be doing anything (I had read online that some people feel transmission lines should have materials of increasing density as you go further down the line). Stuffing of the 'stub' behind/above the driver ended up being with about 20 grams of polyfill type pillow stuffing material on each side - 'fluffed' but still packed enough that it holds itself in there and doesn't fall down.
In terms of tuning it from here, obviously I can make some changes to the internal damping (remove or add polyfill, put more sponges in), or presumably make changes to the shape of the lens - I've noticed that different Karlsonator builds people have done have slots that go higher up (sometimes all the way to the top) or are narrower or wider at the top, but I'm not sure what each of these would actually do to the sound - can anyone who has built more of these than me explain what the different lens parameters will impact?
Before starting the build, I sent xrk971 a PM asking for them to be simulated but was advised despite the higher VAS than the drivers usually used for these, they should work. He asked me to post in the thread in future, which was always my intention once the build was done and I could comment on the drivers.
Anyway, I can recommend these drivers for anyone wanting to do a cheap build - they measure fairly flat from 100Hz to 10kHz with an approx 5dB hump centred around about 100Hz. Subjectively they sound quite good - similar to some Frugel Horn XLs I built around some similarly sized Mark Audio drivers previously, but obviously without going as low. There is a subtle 'boxy' sound which I understand is probably related to the wood construction (see below) but I'm also probably overly sensitive to this because a lot of my listening is on open baffle stuff. However voices sound very natural. They've ended up fairly efficient too - no measurements of this, and I'm using them nearfield, but they can get louder than I'd ever want them with barely visible cone excursion, and apparently these drivers reportedly have a 10mm Xmax so presumably they could be pushed a fair bit further.
See attached picture of the finished speakers. I built them out of a mix of solid timber (side panels, front lens, top panel - ranging from about 12-15mm thickness) and 12mm hardwood plywood (everything else). They are very close to the dimensions from the plans for the 0.53x dual TC9FD version from the start of this thread - I believe I ended up about 10mm shorter and 5mm shallower due to the wood I had to hand. Stuffing was mostly as per XRK's instructions elsewhere in this thread (to help remove 'boxiness' in a wooden build) - primarily melamine sponges everywhere that faces the driver and foamcore on the back of the len, although I also put some 1/2" felt above the sponges about half way up the back cavity + on the back of the top panel, which may or may not be doing anything (I had read online that some people feel transmission lines should have materials of increasing density as you go further down the line). Stuffing of the 'stub' behind/above the driver ended up being with about 20 grams of polyfill type pillow stuffing material on each side - 'fluffed' but still packed enough that it holds itself in there and doesn't fall down.
In terms of tuning it from here, obviously I can make some changes to the internal damping (remove or add polyfill, put more sponges in), or presumably make changes to the shape of the lens - I've noticed that different Karlsonator builds people have done have slots that go higher up (sometimes all the way to the top) or are narrower or wider at the top, but I'm not sure what each of these would actually do to the sound - can anyone who has built more of these than me explain what the different lens parameters will impact?
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Agrajag184 - beautiful build! Is that solid mahogany for the front? Wonderful looking wood grain. Glad the driver worked out and thanks for recommending it. Looks like another great option to add to the 0.53x Karlsonator series.
The lens shape is a DIY tinkering option. If you make the slit go higher it will effectively reduce your TL path length so bass will not be as deep. But you will get more mods highs possibly over a wider angle. Best to okay with foamcore for the shape and then wood. Or start with cheap wood and cut away slowly until you get the sound you like. Boxy sound usually means more foam needed behind the lens. Mount melamine on back of lens and up inside the top of the outer chamber. Good luck!
The lens shape is a DIY tinkering option. If you make the slit go higher it will effectively reduce your TL path length so bass will not be as deep. But you will get more mods highs possibly over a wider angle. Best to okay with foamcore for the shape and then wood. Or start with cheap wood and cut away slowly until you get the sound you like. Boxy sound usually means more foam needed behind the lens. Mount melamine on back of lens and up inside the top of the outer chamber. Good luck!
xrk971 - good guess, but I'm too Australian for mahogany. It is solid timber, but is actually spotted gum - I milled part of a fairly large tree that was cut down from an in-law's yard a few years back and have had a stash of fun smallish pieces for stuff like speaker cabinets since. The fronts are actually laminated from two pieces which were cut in half to bookmatch them - if you look closely there is a faint line where I've joined them and the grain doesn't totally line up about 3/8 of the way across each speaker, but it ended up being quite well hidden. The sides (which you can't see in that picture) are laminated beech panels from our Home Depot equivalent store, rest is boring plywood.
Makes sense re: the slit - I'm surprised that the extra inch or so that it could be moved up would meaningfully shorten the line given that is proportinately a tiny amount compared to length of the whole path, but will take your word for it. How about other changes to the lens, like the width of the the straight top slit (I've seen plans ranging from about 6mm to 10mm), or the radius of the curve at the bottom (or consequently, how much of the driver cone is exposed vs. shielded)? I probably won't actually do any of this, but I have no idea of how the lens actually works acoustically so am curious to learn more.
Re: the boxy sound, it is very subtle and my ear is already getting used to it, but will play around with your suggestions. I've already got melamine sponges filling the sides of the lens chamber as per your instructions earlier in the thread, so I'll temporarily tape some extra ones up the top of the lens where they can't be seen and see what that does, and if that doesn't help, add some more down where the foamcore is stuck to the back of the lens - problem is down there it will be visible from the sides.
Thanks for all your help!
Makes sense re: the slit - I'm surprised that the extra inch or so that it could be moved up would meaningfully shorten the line given that is proportinately a tiny amount compared to length of the whole path, but will take your word for it. How about other changes to the lens, like the width of the the straight top slit (I've seen plans ranging from about 6mm to 10mm), or the radius of the curve at the bottom (or consequently, how much of the driver cone is exposed vs. shielded)? I probably won't actually do any of this, but I have no idea of how the lens actually works acoustically so am curious to learn more.
Re: the boxy sound, it is very subtle and my ear is already getting used to it, but will play around with your suggestions. I've already got melamine sponges filling the sides of the lens chamber as per your instructions earlier in the thread, so I'll temporarily tape some extra ones up the top of the lens where they can't be seen and see what that does, and if that doesn't help, add some more down where the foamcore is stuck to the back of the lens - problem is down there it will be visible from the sides.
Thanks for all your help!
Spotted gum is beautiful wood and great that it is local backyard obtained wood!
I once had a name plate for my speaker binding post plate made from antique oak timber beams from a razed Civil War era barn nearby in Rockville MD. I called the speakers the “Rockville” and later they became the commercial Galion TS Voyagers.
I once had a name plate for my speaker binding post plate made from antique oak timber beams from a razed Civil War era barn nearby in Rockville MD. I called the speakers the “Rockville” and later they became the commercial Galion TS Voyagers.
xrk971,
Interesting story behind that binding post plate timber!
Re: tuning my speakers, I've since stuffed a couple of large melamine cleaning sponges up the top of the front chamber of each speaker and that seems to have further tamed the 'boxiness' (or my ear/brain is just getting used to it).
I'm not sure if you missed the further question I snuck into the middle paragraph of my previous message, re: the theoretical effects of other changes to the lens shape (slit width, lens radius, amount of driver exposed by the lens, etc.) I'm pretty happy with how things sound now so probably won't make any changes, but am curious as to how the lens actually shapes the sound.
Interesting story behind that binding post plate timber!
Re: tuning my speakers, I've since stuffed a couple of large melamine cleaning sponges up the top of the front chamber of each speaker and that seems to have further tamed the 'boxiness' (or my ear/brain is just getting used to it).
I'm not sure if you missed the further question I snuck into the middle paragraph of my previous message, re: the theoretical effects of other changes to the lens shape (slit width, lens radius, amount of driver exposed by the lens, etc.) I'm pretty happy with how things sound now so probably won't make any changes, but am curious as to how the lens actually shapes the sound.
There definitely is an effect to the shape of the lens. You can try various shapes with easy to cut double layer of foamcore etc. basic idea is that a wider opening will sound closer to the bare driver (highs and mids increased) but dispersion angle width decreased. The concept is same as why tweeters or mid ranges have wider dispersion. It’s inversely proportional to radiator diameter. So it is a balance. I have to admit, sometimes it sounds best on some drivers without an aperture. And that’s when you arrive at a folded TL with a single driver speaker. Part of the fun is to experiment. Some drivers that have a lot of in you face screech (some expensive British full ranges with whizzer cones cones to mind) can be tamed quite nicely with a K aperture to flatten that excessive midrange and steeply rising response. In well behaved drivers that are already flat, you will be depressing the response so they might be fine bare.