There is a fourth thing that will improve bass: having the second speaker, and with both speakers placed optimally in the room.
For me that is about a meter or so away from the front wall and very importantly, a little toe-in will really improve the bass and soundstage. The toe-in trick I discovered a few months after completing my Karlsonators.
To get proper soundstage, and bass, the distance between the listener and either speaker should be roughly the same distance that the speakers are apart. That really works for me and it's the only way I listen now.
As a side note; Yesterday I had the opportunity to listen to Klipsch bookshelf speakers about the same size as my 0.53 K's. There is no comparison. The Karlsonators sound much, much better! Thanks for a wonderful speaker, X.
That's good to hear. I was considering buying a very expensive (by my standards) Klipsch "bookshelf" 6.5" speakers, decided to risk less than $100 for parts to try this. Sounds like yours dual foamies are way better than theirs. Can't wait to finish mine.
I made a test run of a single enclosure with an old pair of Radio Shack FE-103 40-1197s (ancient dark/light blue box w/ 'Realistic' brand on it. Finished it earlier tonight and they are amazing. They are 4", so I modified the panel (lengthened it by tipping them up until they fit). They go as deep as the 6.5" speakers in a box, and are MUCH louder (joined the speakers in a parallel configuration, so they were 4 ohms like the box speakers). Can't wait to get started again! may even do another round after that with a pair of 0.4K's for the two Radio Shack speakers... Probably will depend on how badly I burn myself with hot glue on the next pair of speakers.
Ok, I finished my Karlsonator dry run with a pair of old Radio Shack FE-103 4" speakers.
My first concern was having something to keep the labyrinth in place, so I cut a piece of foam to go just inside the labyrinth so I could glue one to each side and put the speaker together with both sides in place.
I followed the plan, but had to make a modification to fit the bigger speakers in. I used some paper (with the speaker size and shape included) into the space where the bottom of the labyrinth would go and then re-cut the foam brace. The blue tape is holding the part I cut off in place, while I re-cut the guide panel.
I glued the guide panels to each side and then started marking, cutting, bending and fitting the labyrinth. Then it was glue time. I thought it would be useful to tie the two sides of a butt-joint with some paper and glue (kind of like drywall tape), but it was a slow, messy and tedious bit of over-engineering.
The plans I had did not have dimensions on the braces, so I free-form cut them and glued them in as I went. Instead of regular glue, I want a little crazy with the hot-melt glue sticks. At 20 4" sticks for a dollar, how could I go wrong? (We'll get back to that later)
I used a drill and drill bit, circle cutting saw and a file to get the speakers settled in, and after a test fit, glued the wood (1/8" Masonite) to the labyrinth. Then a quick transfer of holes to the foam, a couple quick cuts, and we're ready to test fit the speakers.
Testing was done at different levels of completion, each one sounding better than the last. However, until it is sealed up tight and the K-aperture is on, you really aren't hearing the true beauty of this speaker.
Onward to finishing the bracing, adding some felt and pushing in about a quarter bag of 'acousta-stuff' (what can I say, 4 drivers was just $76 bucks, had to get to $100, right?) and I sealed it all up. The penultimate shot is of the speaker sitting on top of the ACA box, getting "burned in"... Nah, I took it off before it started to smell bad or melt the glue. 8)
Remember when I said what could go wrong? Don't click on the last picture unless you like seeing second degree burns from hot glue. Lesson learned. Don't grab a falling piece of foam after slathering it with hot glue - you might just catch it! And no, that's not glue, just the blister... But don't worry, I'm pretty sure I'll live. 8)
My first concern was having something to keep the labyrinth in place, so I cut a piece of foam to go just inside the labyrinth so I could glue one to each side and put the speaker together with both sides in place.
I followed the plan, but had to make a modification to fit the bigger speakers in. I used some paper (with the speaker size and shape included) into the space where the bottom of the labyrinth would go and then re-cut the foam brace. The blue tape is holding the part I cut off in place, while I re-cut the guide panel.
I glued the guide panels to each side and then started marking, cutting, bending and fitting the labyrinth. Then it was glue time. I thought it would be useful to tie the two sides of a butt-joint with some paper and glue (kind of like drywall tape), but it was a slow, messy and tedious bit of over-engineering.
The plans I had did not have dimensions on the braces, so I free-form cut them and glued them in as I went. Instead of regular glue, I want a little crazy with the hot-melt glue sticks. At 20 4" sticks for a dollar, how could I go wrong? (We'll get back to that later)
I used a drill and drill bit, circle cutting saw and a file to get the speakers settled in, and after a test fit, glued the wood (1/8" Masonite) to the labyrinth. Then a quick transfer of holes to the foam, a couple quick cuts, and we're ready to test fit the speakers.
Testing was done at different levels of completion, each one sounding better than the last. However, until it is sealed up tight and the K-aperture is on, you really aren't hearing the true beauty of this speaker.
Onward to finishing the bracing, adding some felt and pushing in about a quarter bag of 'acousta-stuff' (what can I say, 4 drivers was just $76 bucks, had to get to $100, right?) and I sealed it all up. The penultimate shot is of the speaker sitting on top of the ACA box, getting "burned in"... Nah, I took it off before it started to smell bad or melt the glue. 8)
Remember when I said what could go wrong? Don't click on the last picture unless you like seeing second degree burns from hot glue. Lesson learned. Don't grab a falling piece of foam after slathering it with hot glue - you might just catch it! And no, that's not glue, just the blister... But don't worry, I'm pretty sure I'll live. 8)
Attachments
Hey xrk971 - a quick question about a subwoofer, possibly in a full sized Karlsonator...
If I did my math correctly (scaling up from a 0.53), a 1.0 Karlsonator is 31" tall by 16.75" wide and 17.75 deep (outside dimensions, with 1.5" smaller inside dimensions, presuming 3/4" plywood box). Rough math gives a little over 4 cubic feet or about 120 liters to work with.
My thought was to make a sub about that size, and put it in the bottom of my 19" rack. However that means it will be close to the back wall and on the ground (or very close to both).
Two questions:
1) how bad a position would that be for a Karlsonator? I know some bass boxes like to be in corners, but I thought I remembered that Karlsonators prefer some breathing room. Or is that just for the foamies?
2) if it's not too bad a position for the sub, what are some of the parameters I'm looking for in a single sub to put in the K-box? In a different thread (MOAK?), you (xrk971) mentioned 'moderate Qts w/ paper cone, 10" or 12" in diam' (or so my notes say), and referenced a DC 250-8, which has a Qts of 0.38... Anything else to look for to help make this a better fit? Looking for low bass, as the dual 3FE25-16s should be able to handle everything else.
I'm not dead set on a K-box, but some of them have been drop-dead gaaaw-jus! I really like the idea of a two tone, sides dark, and the K panel in a light tone, possibly with a fabric insert (cats in the house). However, the location (in or adjacent to the rack) is a fairly solid requirement.
If not a Karlsonator, what might live in such a space and go fairly low (ideally from 25-30Hz up to about 120-150Hz for the crossover to the 3FE25-16s)?
Thoughts, Ideas, Hints?
If I did my math correctly (scaling up from a 0.53), a 1.0 Karlsonator is 31" tall by 16.75" wide and 17.75 deep (outside dimensions, with 1.5" smaller inside dimensions, presuming 3/4" plywood box). Rough math gives a little over 4 cubic feet or about 120 liters to work with.
My thought was to make a sub about that size, and put it in the bottom of my 19" rack. However that means it will be close to the back wall and on the ground (or very close to both).
Two questions:
1) how bad a position would that be for a Karlsonator? I know some bass boxes like to be in corners, but I thought I remembered that Karlsonators prefer some breathing room. Or is that just for the foamies?
2) if it's not too bad a position for the sub, what are some of the parameters I'm looking for in a single sub to put in the K-box? In a different thread (MOAK?), you (xrk971) mentioned 'moderate Qts w/ paper cone, 10" or 12" in diam' (or so my notes say), and referenced a DC 250-8, which has a Qts of 0.38... Anything else to look for to help make this a better fit? Looking for low bass, as the dual 3FE25-16s should be able to handle everything else.
I'm not dead set on a K-box, but some of them have been drop-dead gaaaw-jus! I really like the idea of a two tone, sides dark, and the K panel in a light tone, possibly with a fabric insert (cats in the house). However, the location (in or adjacent to the rack) is a fairly solid requirement.
If not a Karlsonator, what might live in such a space and go fairly low (ideally from 25-30Hz up to about 120-150Hz for the crossover to the 3FE25-16s)?
Thoughts, Ideas, Hints?
Nice work but probably not optimized - requires running a simulation which gives the following cabinet: 0.44x width and 0.53x height and depth for single driver. Dual would something different.
Mini Karlsonator (0.53X) with Dual TC9FD's
That's exactly what I did. First the frs8, then 3fe25.
My first impressions were the same as yours. I remember regreting that I enlarged the holes in my mini k's for the 3fe25.
What worked for me (no measurements) was placing them near the wall. That fixed the bass.
After 4 weeks with the 3fe25, I am pretty sure that these drivers really need some break in.
Well, if that's not very well optimized (and I did stuff two in, as it's what I had at the time), I can't wait to get the dual FE3's boxes built up and loaded!
Did you see my other post here about a sub in a karlsonator? Also considering an odd looking Z shaped box (from the photo, I presumed an isobaric twin-driver arrangement). Any thoughts, or is that outside your experience?
Yeah, now that you mention it, I remember someone mentioning something like that before (probably you). Thanks for the reminder.
I have already finished my two 0.53 Karlsonators with dual 3FE25 and I can not be happier! Awesome sound! I am not an expert, but it may be the best sound I have ever listened.
As X said, the sound gets the bass when properly closed. But the real magic happens with the two speakers sounding together with good positioning as Skylar said, it's crazy how they sound. I want to thank you all for sharing this project and your work on it!
About my configuration, both of them are close to a wall from behind (around 15cm) and the left one is also close (~5cm) to a side wall. In this position I notice the bass is slightly worse than in optimal positioning, still very good but no sooo good as with >1m distance from any wall. The listening distance is around 2m and their separation is more or less the same. My question is, why does this happen? Is it because of reflections on the walls? Please, note that I am pretty new to this. Could it be improved somehow? Maybe placing something to absorb the sound in the walls, or placing something in the back of the speakers? If impossible I am not complaining at all, it stills being an awesome sound quality, just curious about it.
As X said, the sound gets the bass when properly closed. But the real magic happens with the two speakers sounding together with good positioning as Skylar said, it's crazy how they sound. I want to thank you all for sharing this project and your work on it!
About my configuration, both of them are close to a wall from behind (around 15cm) and the left one is also close (~5cm) to a side wall. In this position I notice the bass is slightly worse than in optimal positioning, still very good but no sooo good as with >1m distance from any wall. The listening distance is around 2m and their separation is more or less the same. My question is, why does this happen? Is it because of reflections on the walls? Please, note that I am pretty new to this. Could it be improved somehow? Maybe placing something to absorb the sound in the walls, or placing something in the back of the speakers? If impossible I am not complaining at all, it stills being an awesome sound quality, just curious about it.
Sounds promising, i sliced my box open to try to find any leakage but nothing, speaker still sounds bad.
I figured it might be the drivers so i quickly made a nola brio trio clone in cardboard and it sounds so much better in every aspect compared to the 0.53x, really hope i did something seriously wrong when making it.
Will pick up some new foamboard today and make a proper speaker.
When near a back wall bass actually goes up by 3dB to 5dB and the tonal balance might be bass-heavy. If you had a BSC circuit employed, you don’t need it if near a back wall. But biggest difference is soundstage - away from wall allows a 3d image of the band to exist in your mind. It’s similar to an acoustic hologram. It needs room for placement of sound sources behind the speaker. I have heard sounds from wider than speaker separation and sometimes some up-down spatialization even. Only happens with a proper amp and good recordings done with ambient mics and minimal processing.
Some breathing room from behind (mine are about 6" away from a window, with about 1.5" of toe-in aimed at the listener) really helps these boxes put you into the sound stage, good recordings, or well mixed movies will sound like theater quality surround sound at times, and the difference in bass compared to against a wall is subtle, but more balanced this way. A good low THD amplifier with good dynamics is a must. My push pull flea amp rocks with these, as does my LM4780 parallel amp. Syrupy sweet, 2nd harmonic pumps like some poorly designed SE tube amps, or cheaper chip/class D amps I've tried are dull and lifeless in comparison, and lacking in detail.
I really want to build up a Pass F4 to try on these with different preamps for voltage gain.
I really want to build up a Pass F4 to try on these with different preamps for voltage gain.
After reading another thread, one question crosses my mind:
Can I lay the Mini-Ks on their side without too much loss?
Can I lay the Mini-Ks on their side without too much loss?
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Try the MoFo for a very simple yet superb sounding SE Class A amp with gain of 0dB and about 11wrms with 24vdc SMPS. All buffer amps need a powerful preamp. For example, to reach 25wrms with F4, you need a preamp that is low distortion even when making 40vpp. The Aksa Lender preamp is great for this purpose.
I'm somewhat confused.
In the post quoted above, you give the scale for a single driver as .44 wide and .53 tall and deep. In post 1519 (page 154), you say it should be .44 high and deep but .55 wide. This is for the same driver (I think) - a single Radio Shack FE103.
Unless there is a noticeable difference, I think I'd prefer the short, shallow, wide one (the one from post 1519 - 13.625 tall x 7.875 x 9.125), rather than the tall, deep skinny one (17 x 9.75 x 7.375).
Interesting tidbit - the "0.53" I built for the dual Radio Shack FE103s is actually (measuring exterior) a 0.50 scale Karlsonator. It still sounded killer. What will a better proportioned box do to the sound? Now I'm really curious...
Note: all measurements stated here are based on Greg B's measurements in post 1510 (31 x 17.75 x 16.75 exterior)
The other option was to put them in a 20" foam cornu... any thoughts on that as an option?
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I like the mofo circuit, but not the cost of the chokes
Something similar with a CCS load is what I'm thinking.