This is a little OT for the full range discussion, but... I have a pair of 126en that I want to put to use. My setup has an active x-over (dbx 234s) feeding a single sub, and a DIY AAB P-P triode amp for the mid-upper range. The speakers I use now for the tube amp are not even worth mentioning (<45/pair).
The plan is to build BK-12m flatpack for my 126en drivers and run it from the existing tube amp. I have an extra x-over freq on 234s that I can use for supertweeters (my hearing is going down a bit). Except for the 234s this is a budget setup, so my idea is to run something like Dayton AMT Mini-8 from a LP-2020A amp with a x-over freq around 8k, the BK-12m from the 80Hz to 8k off the DIY tube amp and a single sub below 80Hz.
I'd appreciate any advise on budget supertweeters that will work reasonably well with BK-12m 126en mains (using an active x-over).
The plan is to build BK-12m flatpack for my 126en drivers and run it from the existing tube amp. I have an extra x-over freq on 234s that I can use for supertweeters (my hearing is going down a bit). Except for the 234s this is a budget setup, so my idea is to run something like Dayton AMT Mini-8 from a LP-2020A amp with a x-over freq around 8k, the BK-12m from the 80Hz to 8k off the DIY tube amp and a single sub below 80Hz.
I'd appreciate any advise on budget supertweeters that will work reasonably well with BK-12m 126en mains (using an active x-over).
Got the Dayton AMT mini-8 and temporarily hooked them up to a dedicated amp and set the active LR4 XO to about 9k. I like them so far, they partially offset my ageing hearing.
Now back to BK-12m (126en). I just received the flatpacks (and related stuff), bought the required clamps (plus two extra 12") and a bottle of each - titebond I and titebond III glue. Two questions:
- this is my first cabinet build, is there a more detailed instruction/video than a single sheet that comes with a flatpack ? I'd like to avoid common pitfalls;
- I want to keep the top of the speakers flat, hence I plan to mount mini-8s just below the 126en using a hole saw (with a separate wiring to the dedicated amp). It is not going to be much lower than the 126en, but I am still a bit worried about such placement...
Now back to BK-12m (126en). I just received the flatpacks (and related stuff), bought the required clamps (plus two extra 12") and a bottle of each - titebond I and titebond III glue. Two questions:
- this is my first cabinet build, is there a more detailed instruction/video than a single sheet that comes with a flatpack ? I'd like to avoid common pitfalls;
- I want to keep the top of the speakers flat, hence I plan to mount mini-8s just below the 126en using a hole saw (with a separate wiring to the dedicated amp). It is not going to be much lower than the 126en, but I am still a bit worried about such placement...
don't worry, be happy - it's a supertweeter, just keep those frequencies lifted up where they belong (a friend has the exact same speaker and has a top mounted Beston RT002A as a super tweet about 12khz and it adds that extra upper air that makes the whole frequency range sound like there's more there, there. You are going to love these speakers.
Modified MK-12m baffles for AMT mini-8s, tried to put these reasonably close to 126en.
The only thing painted will be the baffles - I am not good at painting and also it gives a nice contrast to the cabinet.
Next step - drill more holes for a double set of wires / posts. And then the most scary part - gluing the boxes...
The only thing painted will be the baffles - I am not good at painting and also it gives a nice contrast to the cabinet.
Next step - drill more holes for a double set of wires / posts. And then the most scary part - gluing the boxes...
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This is turning into a build thread, but perhaps it will help some... The only two changes that I've done to the BK-12m kit are the additions of AMT mini-8 as supertweeters on separate connectors and a cork pad at the top of the horn bend. Everything else was pretty much following the build manual verbatim.
I've almost finished the 1st speaker (still using clamps for one side so I can tweak the stuffing to my taste). The 2nd one is glued, waiting for wiring.
First impressions - I do not have an unechoic chamber and reference mics. But based on my subjective hearing - very good treble and decent highs (triamped, or better to say 2.5 amped setup). Sensitivity is at least 6db higher than my generic speakers (good for the small tube-powered mid-range amp). It does not like low sub XO point (a bit of booming), but set at ~90Hz it is very nice. The upper XO point to the supertweeter is now set to 9k, but I may play with that. With the tunable 3-band active XO I can probably throw away my EQ...
I was disappointed with the Lepy 2020A (noise level and occasional lock-ups) that I used for the supertweeters, also it does not use the original Tripath chip (unlike the one I got few years ago), but rather a clone... While an overkill for my setup, I got the Dayton 120 for the supertweeters. Very noticeable improvement (noise level, clarity).
I like this entry level cabinet design very much, but have some complaints about the CNC machining and some delaminations (1..3" long) on the side panels that required low viscosity CA and sanding to fix.
Anyway subjectively the first speaker sounds very nice to my ears on classical, jazz, instrumental, vocal, old disco and rock music. More to come.
I've almost finished the 1st speaker (still using clamps for one side so I can tweak the stuffing to my taste). The 2nd one is glued, waiting for wiring.
First impressions - I do not have an unechoic chamber and reference mics. But based on my subjective hearing - very good treble and decent highs (triamped, or better to say 2.5 amped setup). Sensitivity is at least 6db higher than my generic speakers (good for the small tube-powered mid-range amp). It does not like low sub XO point (a bit of booming), but set at ~90Hz it is very nice. The upper XO point to the supertweeter is now set to 9k, but I may play with that. With the tunable 3-band active XO I can probably throw away my EQ...
I was disappointed with the Lepy 2020A (noise level and occasional lock-ups) that I used for the supertweeters, also it does not use the original Tripath chip (unlike the one I got few years ago), but rather a clone... While an overkill for my setup, I got the Dayton 120 for the supertweeters. Very noticeable improvement (noise level, clarity).
I like this entry level cabinet design very much, but have some complaints about the CNC machining and some delaminations (1..3" long) on the side panels that required low viscosity CA and sanding to fix.
Anyway subjectively the first speaker sounds very nice to my ears on classical, jazz, instrumental, vocal, old disco and rock music. More to come.
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vlad -FWIW, after a few years of doing it myself, I can attest that unless the fabricator of flat packs is willing to accept either a high reject rate on cut parts due to the potential of random delams, or eat the cost of higher quality Apple ply, you’re gonna run into that from time to time.
As for amps, have you given any thought to the ACA 1.6? For my money it’s a home-run, and should have no problem driving what I’d imagine should be a very benign system load of the Fostex, Dayton and a simple XO
As for amps, have you given any thought to the ACA 1.6? For my money it’s a home-run, and should have no problem driving what I’d imagine should be a very benign system load of the Fostex, Dayton and a simple XO
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I got hooked to an instantly tuneable active XO 
since I bought the dbx 234s. I use two separate XO frequencies since I do not want to mix the sub with the 126en and 126en with the supertweeter. The XO box uses L-R 4th order which are fairly steep and the XO frequencies are outside the most critical range.
My tube "midrange" amp is very clean, I've spent a lot of time finding the poles using phase shift measurements with the open NFB and got the lead-lag comp to near perfection. With 126en this amp (~1W-A, ~4.5W-AB) is plenty loud for my needs. If anything the sub and the supertweeter amps are overpowered
since I bought the dbx 234s. I use two separate XO frequencies since I do not want to mix the sub with the 126en and 126en with the supertweeter. The XO box uses L-R 4th order which are fairly steep and the XO frequencies are outside the most critical range.My tube "midrange" amp is very clean, I've spent a lot of time finding the poles using phase shift measurements with the open NFB and got the lead-lag comp to near perfection. With 126en this amp (~1W-A, ~4.5W-AB) is plenty loud for my needs. If anything the sub and the supertweeter amps are overpowered
Regarding the woodwork (and I am definitely not an expert on this), I would rather pay a reasonable premium on the better quality plywood (apple ?) and a bit more accurate CNC machining. My flatpack also came with one critical groove misplaced by 3-4mm, redone, and patched with a glued plank.
One more piece of the build story - after some procrastination I decided to solder the wires to the speaker (I have all the proper equipment) rather than using the quick connects. But 126en has rather poor connection of the coil wires to the pads, so when the pads were heated just enough to make a solid joint with the speaker wires the coil wires simply popped up. I fixed it very carefully but it was scary. They should have added extra few mm to the coil wire so it could be wrapped around the pad instead of just tacking it to the pad recess...
One more piece of the build story - after some procrastination I decided to solder the wires to the speaker (I have all the proper equipment) rather than using the quick connects. But 126en has rather poor connection of the coil wires to the pads, so when the pads were heated just enough to make a solid joint with the speaker wires the coil wires simply popped up. I fixed it very carefully but it was scary
. They should have added extra few mm to the coil wire so it could be wrapped around the pad instead of just tacking it to the pad recess...Finished the second one. Since it is my first cabinet build I was a bit "paranoid" about not being able to open it. So for now I mounted the left wall with 15 cabinet screws (pre-drilled and countersinked). Eventially I will glue it but not before I tweak the stuffing etc... So far I like the way they sound in my room.
Everyone is different, but I did not find the 126en (BK-12m modded box) shouty or fatiguing in the upper treble. Perhaps I need a proper source material. Can someone recommend 1-2 reasonably mastered compositions (available at Amazon) that would highlight the negatives of this driver ? Perhaps a trumpet solo or other high pitched brass ?
I really like them in the role of supertweeters (affordable segment). The idea was to use a full range driver in a horn enclosure extending it to the single sub on the low end and to the supertweeters on the high end, such that XO points are outside the most critical range. The result is very satisfying.
I'll check Cafe Blue, it's a pity Amazon does not have mp3 complement to a CD.
I'll check Cafe Blue, it's a pity Amazon does not have mp3 complement to a CD.
The ST should be as close as possible to the FE126. This suggests they could have been closer.
dave
That suggests a very high temp for sometime… how think is the internal speaker wire?
dave
I tried to get it close but was afraid of the baffle structural rigidity loss - the baffle has a chamfer on the inner side around the 126en. The distance was a deliberate compromise not driven by aesthetics. But perhaps 0.5..1.0" higher would have been more appropriate.
I've used 16awg wire and it was a bit thick, 18awg would have worked much better. My Weller WES51 soldering station is temp controlled, but the driver contact pads were thick and very conducting and so was the 16awg wire. On the second speaker I tinned the wire end and then shaped it to the form of the contact pad hole with a file and a long-nosed pliers and avoided this problem, but still 18awg would have been better. BTW the flex wire that goes to the diaphragm is not damaged, it is still flexible and I do not hear any difference between the two drivers.
Both speakers sound equally good to my taste...
I've used 16awg wire and it was a bit thick, 18awg would have worked much better. My Weller WES51 soldering station is temp controlled, but the driver contact pads were thick and very conducting and so was the 16awg wire. On the second speaker I tinned the wire end and then shaped it to the form of the contact pad hole with a file and a long-nosed pliers and avoided this problem, but still 18awg would have been better. BTW the flex wire that goes to the diaphragm is not damaged, it is still flexible and I do not hear any difference between the two drivers.
Both speakers sound equally good to my taste...
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