Sorry Adolf, i thought the 15" was a good choice. I know your still in the way to develop the crossover. Maybe i am being optimistic. So, 12" will be. 😀
Think it overnight. Or more. If you can handle the cabinetry, and can accept the size, the 15" version does offer that last bit of rumble which makes a sub useless. The 12-incher does pack a punch, but doesn't offer the same amount of sheer wall shaking its bigger brother is capable of.
I just took a good listen after a while today, with my 2-watt single ended creation (EL84 triode connected SE), and maybe the situation with the crossover wasn't all that bad. I'll just have to voice it a bit more full bodied and that should be it. I also spun some Grieg, and I think you won't be disappointed with either one of these B&C coaxes.
Thanks for the advice. But i am feeling a strong temptation to go with the 15". I am a lost case! 😀
Okay, then I'll have to do some excavation through my memos to find you the dimensions for the cabinet. It's something like 120 x 50 x 35cm outer dimensions, tuned to about 45Hz with three ports. I'll have to measure the ports. The cabinet is made from 15mm baltic birch ply, with lots of internal bracing; and bracing is really important here. Crossbracing every 10-15cm of cabinet height is necessary. Around the driver you'll need a double layer of plywood on the front, since the flange is quite thick. If you use MDF or some softer plywood, you'll need a thicker panel, since baltic birch ply is quite stiff. I'd steer clear of MDF though... I prefer plywood. Maybe damping it with bitumen wouldn't hurt, but I haven't tried that.
Now, I do have to warn you. Either you'll hate the end result, or you end up thinking that a lot of quite high end gear sounds mind numbingly boring in comparison. The guy who did the 12-inch version was used to the usual narrow towers with small drivers. Now he's totally addicted to large coaxes.
Now, I do have to warn you. Either you'll hate the end result, or you end up thinking that a lot of quite high end gear sounds mind numbingly boring in comparison. The guy who did the 12-inch version was used to the usual narrow towers with small drivers. Now he's totally addicted to large coaxes.
Sounds like you're going with the coaxial, but I'm having very good luck with a FAST system (Fostex FF85wk and Wavecor WF152BD04).
I listen to a fair amount of classical music and generally go to the Symphony 6-8 times a year (Denver then Seattle) and while living in Boulder would see the Takacs Quartet 4-5 times a year (they wouldn't be my reason to move back to Colorado, but they would help the decision).
One thing to consider with a FAST system is the crossover frequency. Implementation (or my problem with) could play a factor, but I'm getting much better imaging and deeper soundstage with the crossover moved a bit higher than other folks seem to be using. Though I'm still experimenting and need to get the speakers outside for some measurements. For quartets, small groups, etc. low is fine, but for symphonies and concertos I'm enjoying the crossover bumped up a bit (even as high as 750hz). [Mostly been using a Harsch setup]
I listen to a fair amount of classical music and generally go to the Symphony 6-8 times a year (Denver then Seattle) and while living in Boulder would see the Takacs Quartet 4-5 times a year (they wouldn't be my reason to move back to Colorado, but they would help the decision).
One thing to consider with a FAST system is the crossover frequency. Implementation (or my problem with) could play a factor, but I'm getting much better imaging and deeper soundstage with the crossover moved a bit higher than other folks seem to be using. Though I'm still experimenting and need to get the speakers outside for some measurements. For quartets, small groups, etc. low is fine, but for symphonies and concertos I'm enjoying the crossover bumped up a bit (even as high as 750hz). [Mostly been using a Harsch setup]
I believe the 15" coax project (as the other nice projects in this thread) gives a first time builder an already intricate and complex (and/with also coherent and accurate sound) with enough matter to think and compare the next couple of years. The size and dimensions and tuning is a matter of revisiting the speaker/driver/project again. I find it overall a good project for the generous room dimensions Joca has also.
I don't understand why you are so tempted with 15". Which design is it? Tannoy is a good example of a large coax and they are IMO not suitable for classics. The low frequency will not be able to cope with the higher frequency. You need a separate bass driver for that.
And that's Tannoy... Most other big PA drivers just have too high non-linear distortion for my taste. For some that I like, they just need big room (I think yours is not that big either?).
sorry, which 12"-15" driver (PA) is by level of speech, in normal rooms distance below 4 m,
abel to reproduce classic instruments, the Rms is >10, the membran mass more than 100 gr ?, you need max. 2x 8" each cannel to get ~105 dB impulse, 99dB is the max. in disco etc. in germany.
Look for best step response, and IMP for a Tube, i listen to 90% below 1 Watt. if you can´t find data or measurements or only simulations or commercial report be careful,
go listen and try to test it in your rooms with your amp, if it is not possible, try something cheap to get an idea what you need.
abel to reproduce classic instruments, the Rms is >10, the membran mass more than 100 gr ?, you need max. 2x 8" each cannel to get ~105 dB impulse, 99dB is the max. in disco etc. in germany.
Look for best step response, and IMP for a Tube, i listen to 90% below 1 Watt. if you can´t find data or measurements or only simulations or commercial report be careful,
go listen and try to test it in your rooms with your amp, if it is not possible, try something cheap to get an idea what you need.
Very much on the spot.
https://www.youtube.com/watch?v=0egU46lL9QY
http://www.epanorama.net/sff/Audio/Products/Speakers/UREI813C_LR.PDF
http://www.jblproservice.com/pdf/vintage jbl-urei electronics/urei-813.pdf
That is not the case with this 15" project. Is a best (new driver) in LF reproduction not counting with the Doppler effect, bad for all, of course.😀
In this case a LF range driver like sub will produce better results in a multi-way.
In the early days of HI FI the coaxial was the "high end" speaker. Some were three way with electrical crossovers and other were "two way" but used mechanical techniques, like wizzers or other HF coupling. Dayton has brought them back with their neodymium powered "Point Source" models in 3" to 8" configurations. I've not heard one as yet but they look like they would perform well. If anybody has experienced them I'd like a comment.
I couldn't come up with an excuse as to why I hadn't done such testing, so here are a couple of scope pics. I did this as just a quickie experiment. Test setup was a Siglent SDG830 arb generator running into my desktop system amplifiers input, from there to my desktop speakers, measured with an ISEM microphone and amp, whose output was fed to my PoC old analog scope.
Device under test here is not the 15" B&C mentioned here but rather an 8" coaxial from 18Sound, the 8CX401F, with crossover by humble ol' me.
Scope shots are at 400Hz and 2kHz. In the 400Hz shot the low frequency noise from my room can be seen. I was actually quite surprised how close to a square wave they seem. The 400Hz sweep exhibits "drooping" of the wave's tops and bottoms, which is a result of the loudspeakers low frequency response not being infinite. The ringing seen in the 2kHz sweep is what should be expected with finite top end extension.
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the thread started with an inquiry about a speaker design which sounds very good with classical music.
I honestly thought the OP would be happy to have well documented horns by Horst (provided he/she did not shy away from woodworking of course).
the OP however gets hung up on the idea of using a large format driver. that route is also possible but it takes more drivers to deliver the full range. one can venture into large drivers plus horns and so on and there are plenty of assessments gearing the design towards classical music reproduction. the example is Gary D at "beyond the Ariel":
http://www.diyaudio.com/forums/multi-way/100392-beyond-ariel-1259.html#post4381415
anyways, the OP would be well advised to pay attention to the suggestions by people who: 1.) listened to a number of designs and classical music, 2.) are making a reference to a well documented DIY design, and 3.) have no commercial interest whatsoever.
I honestly thought the OP would be happy to have well documented horns by Horst (provided he/she did not shy away from woodworking of course).
the OP however gets hung up on the idea of using a large format driver. that route is also possible but it takes more drivers to deliver the full range. one can venture into large drivers plus horns and so on and there are plenty of assessments gearing the design towards classical music reproduction. the example is Gary D at "beyond the Ariel":
http://www.diyaudio.com/forums/multi-way/100392-beyond-ariel-1259.html#post4381415
anyways, the OP would be well advised to pay attention to the suggestions by people who: 1.) listened to a number of designs and classical music, 2.) are making a reference to a well documented DIY design, and 3.) have no commercial interest whatsoever.
I forgot about this recent design. 96dB at 2.83v and bass is so full that BSC is not needed. Dual PA130-8's in an XKi.
Should be very sensitive and the PA130-8 is one of my favorite full range drivers. Despite its budget price - it sounds great.
http://www.diyaudio.com/forums/full-range/268524-xki-xs-ab-initio-karlson-6th-order-bandpass-48.html
Design here:
An externally hosted image should be here but it was not working when we last tested it.
Should be very sensitive and the PA130-8 is one of my favorite full range drivers. Despite its budget price - it sounds great.
http://www.diyaudio.com/forums/full-range/268524-xki-xs-ab-initio-karlson-6th-order-bandpass-48.html
Design here:
An externally hosted image should be here but it was not working when we last tested it.
Tang Band W5-2143 on top sounds fantastic, or even all by itself in an XKi can reach 60Hz nicely. But for classical, do the FAST thing and XO over below 400Hz to 600Hz or so. Also, use 1st order crossovers (just a coil on woofer and cap on full range, pad the fullrange as need to level match). That helps keep the time alignment. Pick a woofer with minimal breakup (polycones or paper is good generally). The full range here is so well behaved, a simple cap should be fine. Something circa 50uF to 60uF should work. Experiment with the low pass but about 4 to 6mH should do it. Best to measure of course.
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