I am looking to build a two way and use the EV DH1A with a double cutaway K-Tube rather than a horn as I will be listening near field. I have been very pleased with the K-Tube so far. Look forward to more posts on your build. Best regards Moray James.
Hi GM, re. Placing the ports next to the HF horn, Isn't that what the rendering on the klipsch forum describes ? See
https://community.klipsch.com/index...cation-for-belles-with-bass-reflex/?p=1818754
Or do I misunderstand?
Greets!
I mean butted up to the horn instead of out by the walls, i.e. use the vent's end correction air mass 'bubble' to damp the horn mouth's eigenmodes to reduce reflections back to the throat. This 'horn in port' concept was used by Altec for many years before marketing pressure forced them to convert to T/S ducted ports, switching first to fiberglass insulation, then a more attractive foam horn 'baffle' to do it.
GM
I mean butted up to the horn instead of out by the walls, i.e. use the vent's end correction air mass 'bubble' to damp the horn mouth's eigenmodes to reduce reflections back to the throat. This 'horn in port' concept was used by Altec for many years before marketing pressure forced them to convert to T/S ducted ports, switching first to fiberglass insulation, then a more attractive foam horn 'baffle' to do it.
GM
Hi,
I can't find your PM in my message bin. I can also be reached at my username at yahoo.com, if that's more convenient.
I'm going to work on fashioning the mouth braces this weekend . From the klipsch forum, it doesn't look like the driver gasket spacers are "mandatory" for a driver like the kappa 15c (though I realize they are a good idea regardless and will consider fashioning them from the 1/4" MDF I bought for this purpose)
Regarding your proposed use of K-tubes, I like them for treble but sometimes, getting them to work down into the midrange is possible Though to be fair, I had some really crappy midrange compression drivers that I actually threw away after the experiment . http://www.diyaudio.com/forums/full-range/256604-midrange-k-tube.html
Ultimately, ... - my midrange K-tube experiments was ultimately never as successful as the "drunken paraline" that kenpeter and I fashioned on a Friday night with nothing better to do, .. and which amazingly did work despite our best efforts to make a sloppy job of it).
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although I think Transylvania Power had a double size -tube for 2" format, it just doesn't seem to make a lot of sense for midrange. I very much like the regular "The Tube" - they normally used tilted down a bit or up to 30 degrees up from horizontal to match the bass K-coupler.
here's a nice 2-way which I think was built by a member of the Transylvania Power team - this would make a nice alternative to sealed rear chamber LS.
here's a nice 2-way which I think was built by a member of the Transylvania Power team - this would make a nice alternative to sealed rear chamber LS.
I created another post to discuss compression driver / horn choices at
http://www.diyaudio.com/forums/multi-way/272802-any-thoughts-faital-pro-hf200-vs-hf204.html
http://www.diyaudio.com/forums/multi-way/272802-any-thoughts-faital-pro-hf200-vs-hf204.html
fine looking speaker...
hey Freddy: I see that this fellow set up his K-tube similar to mine parallel to the floor at seated ear level. When using a single cutaway tube I rotated mine 90 degrees to his so the solid side of the tube would be facing the outside walls. I much prefer a double cutaway tube set up the same way now. Best regards Moray James.
although I think Transylvania Power had a double size -tube for 2" format, it just doesn't seem to make a lot of sense for midrange. I very much like the regular "The Tube" - they normally used tilted down a bit or up to 30 degrees up from horizontal to match the bass K-coupler.
here's a nice 2-way which I think was built by a member of the Transylvania Power team - this would make a nice alternative to sealed rear chamber LS.
hey Freddy: I see that this fellow set up his K-tube similar to mine parallel to the floor at seated ear level. When using a single cutaway tube I rotated mine 90 degrees to his so the solid side of the tube would be facing the outside walls. I much prefer a double cutaway tube set up the same way now. Best regards Moray James.
Not a lot of progress to report this weekend. Other stuff beckoned. That said, I did get the boxes prepped for gluing the tops on. I'd like to fit the custom fit braces first. I think I'm only going to use one brace per half-mouth rather than two in my renderings.
I also need to ponder whether to stain or veneer these monsters. Birch is always troublesome to finish in anything other than a natural finish
I also need to ponder whether to stain or veneer these monsters. Birch is always troublesome to finish in anything other than a natural finish
Yes, shellac is easy to use. Have to be careful with orange shellac though and dilute it , lest the speaker ends up looking like it has a fake spray on tan . It's definately on my short list . Shellac definately gives the wood some shimmer too compared to Danish oil (tried it on some scrap). I'll make the final decision on which to use or whether to veneer after sanding .
Thanks
I've started bracing the cabs, making micro adjustments with a router+pattern bit guides by a piece of scrap. This can take a little while to get right. I masked off everything relevant and tapped it in securely. I used liquid nails for a secure fit. If this ever comes loose in the future (however unlikely), I'll use some pocket hole joinery on it . BTW, I purposely left a bit of a lip on the front piece, to mate with a grille cover, if I decide to go that way.
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Thanks Freddy. They look better in real life, almost petite (though countless folks used to mini-monitors will no doubt disagree).
In other news, I've ordered a pair of Faital Pro HF144 1.4" compression drivers. They should be able to hit 500 Hz for home SPL levels in an appropriate horn.
The question is, what's the best horn for a 2 way speaker (500 Hz up) ?
The 18sound XT1464 looks tempting (on a very similar compression driver)FaitalPRO HF146 - AVS | Home Theater Discussions And Reviews
Looking into the porting calculations. I've attached DJK's instructions .
1. However, in the text of this doc, .. he recommends against my kappa 15c woofer . I can't understand why. It's low Qts and has a Vas of about 10 cu ft. Is it a question of Xmax ?
2. Roughing out the calculations, it doesn't look like I should need 4 - 5 cu.ft like recommended for the K33 /K43 woofers . Not sure if this is a question of different T/S parameters , data entry error on my part or just dumb luck. The curves on the left are with the stock volume of the belle dog house (about 2.3 cuft less space for the woofer => 2 cufrt approx) and on the right are the winisd calculations for sealed bessel / ported SC4 . If these calculations are correct, I can easily add 1 cuft via a bottom riser without having to port out of the top section.
@DJK, could you comment? Thanks
1. However, in the text of this doc, .. he recommends against my kappa 15c woofer . I can't understand why. It's low Qts and has a Vas of about 10 cu ft. Is it a question of Xmax ?
2. Roughing out the calculations, it doesn't look like I should need 4 - 5 cu.ft like recommended for the K33 /K43 woofers . Not sure if this is a question of different T/S parameters , data entry error on my part or just dumb luck. The curves on the left are with the stock volume of the belle dog house (about 2.3 cuft less space for the woofer => 2 cufrt approx) and on the right are the winisd calculations for sealed bessel / ported SC4 . If these calculations are correct, I can easily add 1 cuft via a bottom riser without having to port out of the top section.
@DJK, could you comment? Thanks
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Vented box size is proportional to the square of the Qts times the Vas.
We are trying to get a B6 response, so the optimum Qts=0.312
0.312^2 = 0.097344
0.25^2 = 0.0625
0.097344/0.0625=1.557504 times the volume.
Viewed the other way, the lower Qts driver requires 0.642 the volume.
The higher the Qts, the lower a driver can go.
The intercept of the box size and bass extension equations is at a Qts=0.312 (the optimum for a B6 equalized alignment). In fact, any other Qts yields a C6, only a Qts=0.312 can yield a B6.
Just about any woofer can made to work OK, the concept seems to work best with a Qts=0.312
Your sim for 3 cu ft shows a F9=40hz, combined with the LaScala horn gain above 100hz it may sound a bit 'lean'.
You should be prepared to change port tunings to find out what sounds the best. Most people at Klipsch preferred a 35hz tuning with around 4.5 cu ft of back volume. Sims showed very little difference in bass response, but performance on music showed a big difference in perceived 'slam' vs deep bass extension.
200 160 125 100 80 63 50 40 31 25 20 HZ
77 80 79 73 72 78 68 60 61 52 51 dB Stock, mouth braced
76 78 78 73 69 75 65 60 66 56 52 4.5 cuft, no ports
76 78 77 75 74 80 70 60 68 54 54 Two 4"dia 10" ports
76 79 78 76 75 80 71 60 68 54 53 Ports cut to 7"
The dual 7" ports give the best 'slam' and still have the bass extension. This is measured in a room, no fancy gating used (note the room problem at 40hz). Note the 7dB increase in output at 31hz (with no EQ). With the recommended Q=2 filter at 35hz the response will be ±3dB from about 31hz on up (in room).
Raw response, and with a small cut in the midbass (Dave Harris with Crites woofer). Dave was using the stock K55V mid driver, it looks like it needs to come down a bit in the 500hz~2Khz range.
We are trying to get a B6 response, so the optimum Qts=0.312
0.312^2 = 0.097344
0.25^2 = 0.0625
0.097344/0.0625=1.557504 times the volume.
Viewed the other way, the lower Qts driver requires 0.642 the volume.
The higher the Qts, the lower a driver can go.
The intercept of the box size and bass extension equations is at a Qts=0.312 (the optimum for a B6 equalized alignment). In fact, any other Qts yields a C6, only a Qts=0.312 can yield a B6.
Just about any woofer can made to work OK, the concept seems to work best with a Qts=0.312
Your sim for 3 cu ft shows a F9=40hz, combined with the LaScala horn gain above 100hz it may sound a bit 'lean'.
You should be prepared to change port tunings to find out what sounds the best. Most people at Klipsch preferred a 35hz tuning with around 4.5 cu ft of back volume. Sims showed very little difference in bass response, but performance on music showed a big difference in perceived 'slam' vs deep bass extension.
200 160 125 100 80 63 50 40 31 25 20 HZ
77 80 79 73 72 78 68 60 61 52 51 dB Stock, mouth braced
76 78 78 73 69 75 65 60 66 56 52 4.5 cuft, no ports
76 78 77 75 74 80 70 60 68 54 54 Two 4"dia 10" ports
76 79 78 76 75 80 71 60 68 54 53 Ports cut to 7"
The dual 7" ports give the best 'slam' and still have the bass extension. This is measured in a room, no fancy gating used (note the room problem at 40hz). Note the 7dB increase in output at 31hz (with no EQ). With the recommended Q=2 filter at 35hz the response will be ±3dB from about 31hz on up (in room).
Raw response, and with a small cut in the midbass (Dave Harris with Crites woofer). Dave was using the stock K55V mid driver, it looks like it needs to come down a bit in the 500hz~2Khz range.
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