Thanks Muddjester, looks great and the metric version will be very handy to those who don't own rulers with inch markings.
Btw, no need to show decimals. I doubt anyone can cut to a fraction of a mm. I would just round down/up to the nearest mm.
Just to sum up my progress till now and ask three more questions.
I have already a pair of needles. The drivers I used were visaton frs 8. They sounded good but I wanted to try the 0.4 karlsonators, so I removed the drivers from the needles and used them with the 0.4x' s, which sound much better. I use them with an unmodded tda 7297 amp and a raspberry pi with an iqaudio dac.
But I want more. My plan is to make the 0.53x with dual 3fe25. My budget is very limited, so i am thinking of following these steps:
1. Buy a pair of 3fe25, place them in my current 0.4x's till I am able to buy the second pair. Available impendances are 4 and 8 Ohms. I am guessing that the correct choice would be the 8 Ohm variant, in order to connect them (later, on the 0.53x) in parallel. Am I right? (That was the first question).
2. The visatons will go back to the needles.
3. Meanwhile, since I have some 12mm mdf, so no cost for me, I 'll build a pair of tabaqs, just for testing them.
4. Next month I am buying the second pair of 3fe25 and decide if I ll make the 0.53 with ply (much cheaper for me, but I am reading here that it may sound boxy), or with foamboard. That would be my second question.
5. So, I till end of March I' ll end up with a pair of dual 3fe25 0.53x for my living room, an empty 0.4x pair, a pair of needles with frs8 for my basement along with the tda7297, and (maybe) a pair of empty tabaqs.
6. In April I will be searching for a better amp. Maybe a diy one, maybe a used one.
My third question is about flash mounting the 3fe25. It seems complicated. Is it ok if I don't? I am thinking of using some 3mm layer (ply, foamboard) wich easier to cut in shape. Would that be ok?
Thanks again for your patience.
I have already a pair of needles. The drivers I used were visaton frs 8. They sounded good but I wanted to try the 0.4 karlsonators, so I removed the drivers from the needles and used them with the 0.4x' s, which sound much better. I use them with an unmodded tda 7297 amp and a raspberry pi with an iqaudio dac.
But I want more. My plan is to make the 0.53x with dual 3fe25. My budget is very limited, so i am thinking of following these steps:
1. Buy a pair of 3fe25, place them in my current 0.4x's till I am able to buy the second pair. Available impendances are 4 and 8 Ohms. I am guessing that the correct choice would be the 8 Ohm variant, in order to connect them (later, on the 0.53x) in parallel. Am I right? (That was the first question).
2. The visatons will go back to the needles.
3. Meanwhile, since I have some 12mm mdf, so no cost for me, I 'll build a pair of tabaqs, just for testing them.
4. Next month I am buying the second pair of 3fe25 and decide if I ll make the 0.53 with ply (much cheaper for me, but I am reading here that it may sound boxy), or with foamboard. That would be my second question.
5. So, I till end of March I' ll end up with a pair of dual 3fe25 0.53x for my living room, an empty 0.4x pair, a pair of needles with frs8 for my basement along with the tda7297, and (maybe) a pair of empty tabaqs.
6. In April I will be searching for a better amp. Maybe a diy one, maybe a used one.
My third question is about flash mounting the 3fe25. It seems complicated. Is it ok if I don't? I am thinking of using some 3mm layer (ply, foamboard) wich easier to cut in shape. Would that be ok?
Thanks again for your patience.
If your amplifier can do 4 ohms, then yes, buy the 8 ohm drivers for later wiring in parallel.
A co-worker built a set in 1/4" plywood, and according to him it took a ton of trial and error getting the stuffing and lining just right. Personally I would build in foamcore first, unless you figure out a way to make the back removable, or design in an access panel of some sort.
I wouldn't bother flush mounting, but if I were to, I would do it with a separate panel cut to fit the surround, and mounted from the front, over the driver. An exacto knife is pretty easy to use for cutting out such shapes. Cut a round mounting hole in a piece of foam board, grab a fine mechanical pencil and trace the edge of the driver as close to the surround as possible, and then remove it. Very carefully trim inside the line and round over the edge slightly by hand. If you are careful it should give a perfect fit.
A co-worker built a set in 1/4" plywood, and according to him it took a ton of trial and error getting the stuffing and lining just right. Personally I would build in foamcore first, unless you figure out a way to make the back removable, or design in an access panel of some sort.
I wouldn't bother flush mounting, but if I were to, I would do it with a separate panel cut to fit the surround, and mounted from the front, over the driver. An exacto knife is pretty easy to use for cutting out such shapes. Cut a round mounting hole in a piece of foam board, grab a fine mechanical pencil and trace the edge of the driver as close to the surround as possible, and then remove it. Very carefully trim inside the line and round over the edge slightly by hand. If you are careful it should give a perfect fit.
Thanks for your quick reply.
If I ll make them out of ply, I ll probably test the dumbening without the base. The base will be the last to glue in place. Speaker on a flat surface, some weight above them. Second step would be just screwing the base.
As for flash mounting, I ll leave it as is. If I find some time then I ll follow your suggestions.
If I ll make them out of ply, I ll probably test the dumbening without the base. The base will be the last to glue in place. Speaker on a flat surface, some weight above them. Second step would be just screwing the base.
As for flash mounting, I ll leave it as is. If I find some time then I ll follow your suggestions.
I want to build one in summer from 1/2" MDF using a 4" Tang Band drivers.
Just a plan.......
So, now that the honeymoon period is over, my thoughts on the TC9FD 0.4x Karlsonator-
Very impressive, tight, and natural sounding bass, not unlike you would get from quality studio monitors.
Dialog and ambient music sounds incredibly present and naturally. The sound is around you, not coming at you.
"Imaging" and stereo effect is wonderful. Much better in-room result from the wide dispersion.
Surprisingly efficient, I'm running them off of a flea power tube amp, and I would wager the amplifier will put out maybe 1.2 watts at clip. This is plenty loud enough without discernable loss in audio quality. Pushing it to party levels is where it gets funky.
I like them so much I'm building another set with the 3FE25, in .053x scale. Better sensitivity and efficiency.
My only comment that isn't glowingly positive, (but is definitely not a deal breaker, or necessarily negative) is that once you are off-axis 30~40° or so, that the higher frequency is less noticeable, and could use a bit of assistance. This is no problem for a fixed listening position, but due to our unique listening/living area, I wouldn't mind augmenting the higher frequency so that the "sweet spot" is a bit wider. We have a couch next to our bed, and dealing with fussy kids has us going back and forth between the two. The only thing lacking from our bed is some high frequency sparkle.
So, naturally fitting the karlson theme, I'm thinking of building a pair of k-tube tweeters to go with them I figure the wider dispersion would be a natural fit.
Fitting the theme of the builds, is there an affordable ($5~10 each) tweeter that would be a good fit for a k-tube to put on top of these guys? I'm looking to make an order from Parts Express tonight, so I'll be grabbing some from there when I order.
Do I want a compression driver? Dome? Forgive me, but I'm not well versed in higher frequency drivers much at all...
Very impressive, tight, and natural sounding bass, not unlike you would get from quality studio monitors.
Dialog and ambient music sounds incredibly present and naturally. The sound is around you, not coming at you.
"Imaging" and stereo effect is wonderful. Much better in-room result from the wide dispersion.
Surprisingly efficient, I'm running them off of a flea power tube amp, and I would wager the amplifier will put out maybe 1.2 watts at clip. This is plenty loud enough without discernable loss in audio quality. Pushing it to party levels is where it gets funky.
I like them so much I'm building another set with the 3FE25, in .053x scale. Better sensitivity and efficiency.
My only comment that isn't glowingly positive, (but is definitely not a deal breaker, or necessarily negative) is that once you are off-axis 30~40° or so, that the higher frequency is less noticeable, and could use a bit of assistance. This is no problem for a fixed listening position, but due to our unique listening/living area, I wouldn't mind augmenting the higher frequency so that the "sweet spot" is a bit wider. We have a couch next to our bed, and dealing with fussy kids has us going back and forth between the two. The only thing lacking from our bed is some high frequency sparkle.
So, naturally fitting the karlson theme, I'm thinking of building a pair of k-tube tweeters to go with them
I figure the wider dispersion would be a natural fit.Fitting the theme of the builds, is there an affordable ($5~10 each) tweeter that would be a good fit for a k-tube to put on top of these guys? I'm looking to make an order from Parts Express tonight, so I'll be grabbing some from there when I order.
Do I want a compression driver? Dome? Forgive me, but I'm not well versed in higher frequency drivers much at all...
High frequencies beaming
Since the high frequencies are not as well dispersed off axis in the Karlsonator, I wonder if there might be another fix besides adding a separate tweeter.
Perhaps the Karlson opening could have some sort of "phase plug" in the center which would distribute the high frequencies more off axis. The Karlson slot would have to be cut wider to allow adding the equivalent to a phase plug at the center of the opening.
Since the high frequencies are not as well dispersed off axis in the Karlsonator, I wonder if there might be another fix besides adding a separate tweeter.
Perhaps the Karlson opening could have some sort of "phase plug" in the center which would distribute the high frequencies more off axis. The Karlson slot would have to be cut wider to allow adding the equivalent to a phase plug at the center of the opening.
My experience with K aperture is that it makes the polars wider than without the aperture. Take for example these measurements from an XKi.
q
For more sparkle add the Dayton Pod (no Ktube) and High Pass with about 1uF cap.
Dayton Audio AMTPOD-4 Air Motion Transformer Automotive Tweeter Pair
For a K tube use a 1in dome tweeter 1in PVC k tube.
q
For more sparkle add the Dayton Pod (no Ktube) and High Pass with about 1uF cap.
Dayton Audio AMTPOD-4 Air Motion Transformer Automotive Tweeter Pair
For a K tube use a 1in dome tweeter 1in PVC k tube.
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Adding a tweeter
If adding a tweeter, it makes sense to try different locations for the tweeter. A friend of mine added a tweeter to enhance his full range Fostex F200A mounted in transmission line speakers which were beaming significantly at the highest frequencies.
Recognizing the beaming that he experienced, he purchased the tweeter and ultimately placed the tweeter on the floor behind the speaker facing up at the ceiling. After thinking about it, it makes sense since the speaker is providing the direct sound, what is missing is the off axis sound. The speaker box was blocking the on axis sound from his added tweeter, but the tweeter was able to enhance the rest of the sound field.
Something to think about.
Retsel
If adding a tweeter, it makes sense to try different locations for the tweeter. A friend of mine added a tweeter to enhance his full range Fostex F200A mounted in transmission line speakers which were beaming significantly at the highest frequencies.
Recognizing the beaming that he experienced, he purchased the tweeter and ultimately placed the tweeter on the floor behind the speaker facing up at the ceiling. After thinking about it, it makes sense since the speaker is providing the direct sound, what is missing is the off axis sound. The speaker box was blocking the on axis sound from his added tweeter, but the tweeter was able to enhance the rest of the sound field.
Something to think about.
Retsel
I like them so much I'm building another set with the 3FE25, in .053x scale. Better sensitivity and efficiency.
My only comment that isn't glowingly positive, (but is definitely not a deal breaker, or necessarily negative) is that once you are off-axis 30~40° or so, that the higher frequency is less noticeable, and could use a bit of assistance. This is no problem for a fixed listening position, but due to our unique listening/living area, I wouldn't mind augmenting the higher frequency so that the "sweet spot" is a bit wider. We have a couch next to our bed, and dealing with fussy kids has us going back and forth between the two. The only thing lacking from our bed is some high frequency sparkle.
So, naturally fitting the karlson theme, I'm thinking of building a pair of k-tube tweeters to go with them
Why don't you put 3FE25's in the 0.40x boxes? Producing high frequency is their specialty. In fact, in my dual 3FE25 0.53x K's, I had to add baffle steps to tame the highs.
Or, just build 0.53x with dual 3FE25-16 Ohm in parallel (like I did) and be done with it. That combination is highly recommended.
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I've got four of the 3FE25-16 right here, just slowly finding time to get the parts all cut up, but the kids aren't giving me much time
I haven't had much time at home that isn't spent juggling kids, and when we do have downtime the table is either in use, or I've got other things that require my attention. I'll hopefully have the 0.53x set with the 3FE25's done this week.
I might wait until I finish the bigger K's to fool with tweeters. Either way I'm thinking of doing a third 0.41x to use as a center channel, and putting my current two as rear channels, with the new 0.53x doing the front two/main channels.
I haven't had much time at home that isn't spent juggling kids, and when we do have downtime the table is either in use, or I've got other things that require my attention. I'll hopefully have the 0.53x set with the 3FE25's done this week.
I might wait until I finish the bigger K's to fool with tweeters. Either way I'm thinking of doing a third 0.41x to use as a center channel, and putting my current two as rear channels, with the new 0.53x doing the front two/main channels.
Attachments
I had to order parts anyway, so I put together a order at Parts Express, and among the usual bits and pieces (resistors, speaker terminals, etc) I ordered a third TC9FD to build a centre channel, a few of the affordable buyout tweeters (mostly for car audio projects) a couple GRS piezo horn drivers (for some k-tube and other experiments ) and on an impulse buy, some big, stupid, gaudy woofers:
Titan 10" Coated Paper Cone Red Surround Woofer 4 Ohm
It took all my willpower not to buy the big purple and yellow ones
I only needed $25 to hit free shipping anyway, so I figured why not. Might do up a push-push box for my car. $10 each they'll be fun for party speakers at the worst. Unless any foamboard ideas for them come up, they do have a list of parameters, at least.
) and on an impulse buy, some big, stupid, gaudy woofers:Titan 10" Coated Paper Cone Red Surround Woofer 4 Ohm
It took all my willpower not to buy the big purple and yellow ones
I only needed $25 to hit free shipping anyway, so I figured why not. Might do up a push-push box for my car. $10 each they'll be fun for party speakers at the worst. Unless any foamboard ideas for them come up, they do have a list of parameters, at least.
Man, that was much more nerve wracking than the smaller K's, but I've gotten one of the 0.53's together. Some minor issues with everything lining up, but not a big deal.
Waiting on parts (speaker terminals primary, and spade connectors) so it's not wired up yet, but even the girl likes it better in the larger scale, says it looks fancy
If I like how these turn out I'm doing a set in wood. If they're even at least as good as the smaller K's they deserve a nice heirloom quality enclosure
Waiting on parts (speaker terminals primary, and spade connectors) so it's not wired up yet, but even the girl likes it better in the larger scale, says it looks fancy
If I like how these turn out I'm doing a set in wood. If they're even at least as good as the smaller K's they deserve a nice heirloom quality enclosure
Attachments
If I like how these turn out I'm doing a set in wood. If they're even at least as good as the smaller K's they deserve a nice heirloom quality enclosure
It looks very good in black, but I agree that wood will be longer lasting and better all round.
I have heard the 0.40x and it's not a patch on the 0.53x with dual 3FE25. I think you're in for a nice surprise.
