I have not tried the Behringer DCX 2496 - But from what I have read, miniDSP is way better.
Nothing beats, IMO a good soundcard - Though it is not as simple as a stand-alone solution -Example from miniDSP.
Nothing beats, IMO a good soundcard - Though it is not as simple as a stand-alone solution -Example from miniDSP.
If your hearing is like mine, there's no sense paying for expensive drivers above 12kHz.
Get reproduction of upright string bass correct, and most music will be (reasonably) accurate.
FYI - crossovers that reconvert input signals tend to add artifacts not found in passive designs. I prefer the Marchand to the Behringer, in the survey shown below.
The best active Crossover I've heard to date used the miniDSP driving a Linkwitz 4 way.
Nothing wrong with well built passive designs, for all their limitations.
http://www.thewelltemperedcomputer.com/HW/ActiveCrossover.htm
Sent from my Nexus 6 using Tapatalk
Well if you want to go for a 4-way system you may need the miniDSP.
DCX2496 may do good if you mod the output stage and builds a 3 way system.
Find your upper limit (frequency test)
https://www.youtube.com/watch?v=qNf9nzvnd1k
DCX2496 may do good if you mod the output stage and builds a 3 way system.
Find your upper limit (frequency test)
https://www.youtube.com/watch?v=qNf9nzvnd1k
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Well LPSCAD is out of the question, 1000EUR is not going to happen.
LinearX website is no longer in operation and I cant find the download link for enclosure shop.
What about BassBoxPro?
LinearX website is no longer in operation and I cant find the download link for enclosure shop.
What about BassBoxPro?
With this you need 4 dac (may find cheap on ebay)
https://www.minidsp.com/products/minidspkits/nanodigi-2x8-k
Or this will do amazing job
https://www.minidsp.com/products/minidsp-in-a-box/minidsp-10x10-hd
https://www.minidsp.com/products/minidspkits/nanodigi-2x8-k
Or this will do amazing job
https://www.minidsp.com/products/minidsp-in-a-box/minidsp-10x10-hd
I really cannot believe how cheap these DSP systems have become. Its incredible how much power and how many features these designers have packed into them. Thank you for the suggestion and the links.
I have a question about lobing in the MTM arrangement.
Is this only a problem when the drivers are placed to close to each other? If I put a great enough distance between the 3 drivers will this alleviate any of the lobing effect? I am going to use sealed tweeter and sealed dome mid range in this part of the design. I figure this means that there is no internal box volume calculations to be done.
I used this to calculate the distance Vented Audio Speaker Enclosure Designs - KBpps.com
The mid dome I entered is a Dayton Audio DC50FA-8 just to see what happens. Vas, Vdr, Dp and and Vb are all zero which returns an enclosure of zero, which is what I would expect.
But if I select a crossover freq of 7000hz this gives me a distance between the mids of 9.8cm but my tweeter is 10.5cm. What gives? It wont fit in this little gap. If I increase the distance between the mids to 15cm or 18cm or even 20cm what effect will this have on the lobing? Is it going to sound like crap or is this 9.8cm distance a minimum required to prevent lobing? Im a bit lost.
Is this only a problem when the drivers are placed to close to each other? If I put a great enough distance between the 3 drivers will this alleviate any of the lobing effect? I am going to use sealed tweeter and sealed dome mid range in this part of the design. I figure this means that there is no internal box volume calculations to be done.
I used this to calculate the distance Vented Audio Speaker Enclosure Designs - KBpps.com
The mid dome I entered is a Dayton Audio DC50FA-8 just to see what happens. Vas, Vdr, Dp and and Vb are all zero which returns an enclosure of zero, which is what I would expect.
But if I select a crossover freq of 7000hz this gives me a distance between the mids of 9.8cm but my tweeter is 10.5cm. What gives? It wont fit in this little gap. If I increase the distance between the mids to 15cm or 18cm or even 20cm what effect will this have on the lobing? Is it going to sound like crap or is this 9.8cm distance a minimum required to prevent lobing? Im a bit lost.
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One of many good papers: "Vertically Symmetric Two-Way Loudspeaker Arrays Reconsidered" Biro Technology
Biro Technology
This paper has the commonly used math for M-T and M-M spacing requirements for controlled lobing with a MTM topology.
Dunlavy 4-way designs with 1st order crossovers required small diameter(2"-3") upper midrange drivers next to the tweeter, and then added lower midrange drivers.
Dunlavy designs used:
-1st order crossovers for phase control
-Symmetric point source directivity generated with symmetric drivers WMmTmMW
-Drivers sized to keep Center-to-Center distances close to a quarter wavelength of the crossover frequency, which requires WMmTmMW
-Constructing stepped baffles to produce time alignment among all drivers
-THICK absorption material to control stepped baffle edge diffraction, and also to restrict the off-axis SPL to provide a more constant directivity. The felt in the cavity provides no significant horn-loading, but it does help restrict the off-axis SPL and provide a more constant directivity.
---------
Today, most MTM designs use steeper slopes(3rd-4th order) with crossovers around 1.6kHz - 1.8kHz for acceptable lobing control. MiniDSP performs time delay correction. For your 4-way WMmTmMW goal with MiniDSP you might consider flat baffle boxes W--MmTmM--W with:
1" dome
4" upper midrange
8" lower midrange
15" woofer (large heavy cabinets)
Attachments
One of the best paper I have read about MTM is this by Dr. Keele.
http://www.xlrtechs.com/dbkeele.com...ear Phase Digital Crossover Flters Part 2.pdf
I couldn't find part 1 any more for some reasons...
http://www.xlrtechs.com/dbkeele.com...ear Phase Digital Crossover Flters Part 2.pdf
I couldn't find part 1 any more for some reasons...
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Thank you linesource. I read that paper and some of it I understood and some it went straight over my head. I was going to use 1" dome 2" upper mid,8" lower mid and 12" woofer.
Another excellent resource. Many thanks. Its all helping with my education. Select drivers and crossover freq first and then go on to box design and tie alignment. Yes?
In the address line, I changed the 2 of "Part 2" to a 1 and the browser found the Part 1 pdf.
I have not read the docs, but I thought the lobing/beaming was made more acceptable by closing up the space between drivers that are sending out the same frequencies.
i.e Treble to Mid should be small because around the crossover both drivers are sending out the same frequencies.
Similarly Mid to Bass driver gap should be small, but because the wavelength of the frequencies is larger, they will tolerate a higher centre to centre spacing for similar lobing/beaming.
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Instead of a miniDSP + 4 DACs you could just use a 8-channel DAC. And using Acourate as software to create your digital linear phase crossovers, plus room correction, plus driver time-alignment...I find it a lot more powerful than miniDSP and 4 DACs...
8-channel DACs are called soundcards in the pro world and are DAC & ADC, allowing you to also take measurements with a microphone, which you will need too. Many alternatives available, eg from more to less expensive: Prism Titan, Lynx Hilo, Focusrite line, amongst others. The Hilo is really a 6-way, but I use a digital out to an older Metrum Octave DAC that I had and use it as additional 2 channels, so 4-way.
I encourage you to read the articles I pointed to on post #8 to get a feel of what using Acourate and a 8-way DAC would allow you to do. Those articles were a milestone in my journey.
8-channel DACs are called soundcards in the pro world and are DAC & ADC, allowing you to also take measurements with a microphone, which you will need too. Many alternatives available, eg from more to less expensive: Prism Titan, Lynx Hilo, Focusrite line, amongst others. The Hilo is really a 6-way, but I use a digital out to an older Metrum Octave DAC that I had and use it as additional 2 channels, so 4-way.
I encourage you to read the articles I pointed to on post #8 to get a feel of what using Acourate and a 8-way DAC would allow you to do. Those articles were a milestone in my journey.
If pro audio interface route is chosen, I would strongly recommend Equilibrium EQ plugin for he filter job. This is probably the highest quality digital filter software that mastering people are actually using. Extremely powerful and versatile. Many people who don't know about digital world tend to think all the digital programs sound the same, but that is wrong. The truth is most digital filters sound awful except a few.
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miniDSP has the OpenDRC-DA8 which is basically the 2x4 HD with 8 output channels.
I'm also making a 4 way active speaker, Dunlavy style
I would encourage you to pick your favorite Dunlavy-design speaker & adhere as close as possible to his principles of low-Q sealed enclosures, time-aligned symmetrical driver array, 1st order crossovers, F13 felt around the drivers, modifying box depth (volume) to suit your driver choices requirements. Go with miniDSP 2x4HD for sure & amps of your choice. They can be much lower-powered than for passive speakers, even SET tube amps or class A's for the highs with Class Ds for the woofers. Just my opinion...
About a year ago, I followed John Dunlavy's design methodologies & built clone SC-IVs, but using inexpensive drivers from Parts Express, miniDSP 2x4 & multiple LM3886 amps for these "prototypes" for proof-of-concept. I used the Umic & REW to dial them in & was surprised when I ended up with +/-2db from 40-20K from the seated location. The 10" drivers I chose (I later discovered) were best suited for vented enclosures, but I consider Dunlavy a genius regarding the details, so I'm just getting the most I can from a sealed enclosure for these drivers, hence the 40 hz. I'm using a Linkwitz Transform biquad in the MiniDSP to bring them down to about 25 Hz, but I run out of xmax at very high volumes. I am shocked at how great they sound! I've had some great speakers in my past, AR-3s, Altec VOT, & some higher end DIYs. These are better. It could just be because with active xovers, each driver voice coil is better controlled by the amplifier with no passive components in between, or because I calibrated them to the room with the miniDSP. Probably both! I've had some musician friends listen to them & they agreed that what they liked was that they don't sound like speakers! They claim to be hearing things in familiar music that they never heard before. The pianist shouted, "I can hear the hammers hitting the wire"!
Now, I'm planning some SC-V clones, using somewhat better drivers, with 2-GRS 12", 2- Peerless 6.5", 2-Peerless 3.5", Peerless Dome or dual ring concentric tweeter. With this 4-way design, the 3.5" drivers will handle from 320 hz to 4000 hz. so they'll handle most of the voice & instrument range. Dunlavy always felt the SC-V was the most accurate speaker he ever built, even though the SC-IVs were the most popular.
The 12" drivers I'm using should provide bass flat to about 20hz , -3db at 16 hz using a biquad in the miniDSP for a Linkwitz Transform. The LM3886 amps have been great, but I also built some JLH class A's to try for the upper mids/tweeter just to see if I like them better. The woofers will probably be driven by some more powerful class D amps. I drive the miniDSP & amps with my Anthem AVM20 preamp which I still really like after all these years.
I attended the 2016 Rocky Mountain Audio Fest last fall to listen to all that I could. I took some sample music I'm very familiar with, then used Shazam to identify the songs they were playing. I really felt at the end of the day, my $400 speakers/amps, could match or beat most of what I heard there, at pennies on the dollar. I felt only the Focal Utopias & Martin Logan Electrostatics were better in some areas. When I played the same music that I heard there, it reinforced that I'm on the right road, considering my circumstances.
Mine continue to be budget builds, since I'm retired on fixed income, but the sound so far has been simply outstanding. It has rekindled my passion for excellent music reproduction. I'm planning a music-listening/home theater room next year next where this next pair will live. Now I'm studying all about the ideal room attributes for best acoustics.
I would encourage you to pick your favorite Dunlavy-design speaker & adhere as close as possible to his principles of low-Q sealed enclosures, time-aligned symmetrical driver array, 1st order crossovers, F13 felt around the drivers, modifying box depth (volume) to suit your driver choices requirements. Go with miniDSP 2x4HD for sure & amps of your choice. They can be much lower-powered than for passive speakers, even SET tube amps or class A's for the highs with Class Ds for the woofers. Just my opinion...
About a year ago, I followed John Dunlavy's design methodologies & built clone SC-IVs, but using inexpensive drivers from Parts Express, miniDSP 2x4 & multiple LM3886 amps for these "prototypes" for proof-of-concept. I used the Umic & REW to dial them in & was surprised when I ended up with +/-2db from 40-20K from the seated location. The 10" drivers I chose (I later discovered) were best suited for vented enclosures, but I consider Dunlavy a genius regarding the details, so I'm just getting the most I can from a sealed enclosure for these drivers, hence the 40 hz. I'm using a Linkwitz Transform biquad in the MiniDSP to bring them down to about 25 Hz, but I run out of xmax at very high volumes. I am shocked at how great they sound! I've had some great speakers in my past, AR-3s, Altec VOT, & some higher end DIYs. These are better. It could just be because with active xovers, each driver voice coil is better controlled by the amplifier with no passive components in between, or because I calibrated them to the room with the miniDSP. Probably both! I've had some musician friends listen to them & they agreed that what they liked was that they don't sound like speakers! They claim to be hearing things in familiar music that they never heard before. The pianist shouted, "I can hear the hammers hitting the wire"!
Now, I'm planning some SC-V clones, using somewhat better drivers, with 2-GRS 12", 2- Peerless 6.5", 2-Peerless 3.5", Peerless Dome or dual ring concentric tweeter. With this 4-way design, the 3.5" drivers will handle from 320 hz to 4000 hz. so they'll handle most of the voice & instrument range. Dunlavy always felt the SC-V was the most accurate speaker he ever built, even though the SC-IVs were the most popular.
The 12" drivers I'm using should provide bass flat to about 20hz , -3db at 16 hz using a biquad in the miniDSP for a Linkwitz Transform. The LM3886 amps have been great, but I also built some JLH class A's to try for the upper mids/tweeter just to see if I like them better. The woofers will probably be driven by some more powerful class D amps. I drive the miniDSP & amps with my Anthem AVM20 preamp which I still really like after all these years.
I attended the 2016 Rocky Mountain Audio Fest last fall to listen to all that I could. I took some sample music I'm very familiar with, then used Shazam to identify the songs they were playing. I really felt at the end of the day, my $400 speakers/amps, could match or beat most of what I heard there, at pennies on the dollar. I felt only the Focal Utopias & Martin Logan Electrostatics were better in some areas. When I played the same music that I heard there, it reinforced that I'm on the right road, considering my circumstances.
Mine continue to be budget builds, since I'm retired on fixed income, but the sound so far has been simply outstanding. It has rekindled my passion for excellent music reproduction. I'm planning a music-listening/home theater room next year next where this next pair will live. Now I'm studying all about the ideal room attributes for best acoustics.
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