The DIY Near-Field Monitor Project, Round Two
- Thread starter Consul
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mhelin
Well-known member
[quote author="Consul"]
Design Idea Three: The Most Radical of Them All
[/quote]
For the nearfields there are ready-made coaxials from Seas:
http://www.madisound.com/cgi-bin/index.cgi?exact_match=yes&product=SEC&cart_id=3113121.21533
Here you can find schematics for a T18REX crossover:
http://www.hifitalo.fi/shop/sivut/aw7_suodin.htm
Edit: seems that the driver is custom T18REX/XACG with aluminium diaphragm tweeter (you can though buy it from Hifitalo in Finland).
Design Idea Three: The Most Radical of Them All
[/quote]
For the nearfields there are ready-made coaxials from Seas:
http://www.madisound.com/cgi-bin/index.cgi?exact_match=yes&product=SEC&cart_id=3113121.21533
Here you can find schematics for a T18REX crossover:
http://www.hifitalo.fi/shop/sivut/aw7_suodin.htm
Edit: seems that the driver is custom T18REX/XACG with aluminium diaphragm tweeter (you can though buy it from Hifitalo in Finland).
Consul
Well-known member
I've already been looking at those coax drivers from Seas. They've been used in at least one high-end speaker I've seen, though I won't call that a ringing endorsement just yet.
The Seas L18/27TBFCG midwoofer/speaker combo is $40 cheaper for both sides than those coax things.
The Seas L18/27TBFCG midwoofer/speaker combo is $40 cheaper for both sides than those coax things.
mhelin
Well-known member
If you use separate tweeter and woofer try to place them as close to each other as possible (overlap them slightly), this helps in near field situation in integrating the sound fields. A small neo tweeter like Vifa D26NC55 would be easier to use in this case.
Also be sure you get the H1224 L18RNXP model for the woofer, it's resonance is higher (@7kHz) due to the new cone design.
Also here is another coax design by Tony Gee:
http://www.humblehomemadehifi.com/USB.html
Also be sure you get the H1224 L18RNXP model for the woofer, it's resonance is higher (@7kHz) due to the new cone design.
Also here is another coax design by Tony Gee:
http://www.humblehomemadehifi.com/USB.html
Svart
Well-known member
what about these:
http://www.madisound.com/cgi-bin/index.cgi?cart_id=3113121.21533&pid=1961
wouldn't a coaxial unit negate the whole delay/offset problem with multiple drivers?
EDIT: I see that Mhelin just posted something using those..
http://www.madisound.com/cgi-bin/index.cgi?cart_id=3113121.21533&pid=1961
wouldn't a coaxial unit negate the whole delay/offset problem with multiple drivers?
EDIT: I see that Mhelin just posted something using those..
Svart
Well-known member
I'd also like to see:
http://www.madisound.com/cgi-bin/index.cgi?cart_id=8820274.10286&pid=987
and:
http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=276-402
or
http://www.madisound.com/cgi-bin/index.cgi?cart_id=8820274.10286&pid=2139
together in a box.
http://www.madisound.com/cgi-bin/index.cgi?cart_id=8820274.10286&pid=987
and:
http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=276-402
or
http://www.madisound.com/cgi-bin/index.cgi?cart_id=8820274.10286&pid=2139
together in a box.
Marik
Well-known member
[quote author="Svart"]I'd also like to see:
http://www.madisound.com/cgi-bin/index.cgi?cart_id=8820274.10286&pid=987
[/quote]
That's a very nice driver. Unfortunately, it is a real PITA to use. I highly doubt you could even mate it with ribbons (esp. Aurum Cantus), as because of its cone break up modes the crossover frequency should be quite low.
I in fact, would love to try some coaxials. Unfortunately, all I see is polymer cones. I want Aluminum or Magnesium.
http://www.madisound.com/cgi-bin/index.cgi?cart_id=8820274.10286&pid=987
[/quote]
That's a very nice driver. Unfortunately, it is a real PITA to use. I highly doubt you could even mate it with ribbons (esp. Aurum Cantus), as because of its cone break up modes the crossover frequency should be quite low.
I in fact, would love to try some coaxials. Unfortunately, all I see is polymer cones. I want Aluminum or Magnesium.
Consul
Well-known member
Those are all way too expensive for my tastes. I'm thinking "bargain" here:
http://www.partsexpress.com/pe/pshowdetl.cfm?&Partnumber=295-362
And at $25 apiece, an experiment not panning out won't break the bank.
The Dayton drivers get very high marks from Zaph, which again will have to be good enough for me. I have something interesting in mind for these. I'll get back to everyone when I have something more concrete.
http://www.partsexpress.com/pe/pshowdetl.cfm?&Partnumber=295-362
And at $25 apiece, an experiment not panning out won't break the bank.
The Dayton drivers get very high marks from Zaph, which again will have to be good enough for me. I have something interesting in mind for these. I'll get back to everyone when I have something more concrete.
Marik
Well-known member
[quote author="Consul"]Those are all way too expensive for my tastes. I'm thinking "bargain" here:
http://www.partsexpress.com/pe/pshowdetl.cfm?&Partnumber=295-362
And at $25 apiece, an experiment not panning out won't break the bank.
The Dayton drivers get very high marks from Zaph, which again will have to be good enough for me. I have something interesting in mind for these. I'll get back to everyone when I have something more concrete.[/quote]
Actually, those got very high scores from a few people, even compared to L18. It seems there is no definite concensus which driver is a clear winner.
On paper, the Dayton might be even better for monitoring, as it does not have that 4db peak around 850Hz. If you try to actively cross it around 2K you might get away with those "camel back" peaks on 6.2K and 10db on 9K, even without notch.
Most definitely, the price is right.
http://www.partsexpress.com/pe/pshowdetl.cfm?&Partnumber=295-362
And at $25 apiece, an experiment not panning out won't break the bank.
The Dayton drivers get very high marks from Zaph, which again will have to be good enough for me. I have something interesting in mind for these. I'll get back to everyone when I have something more concrete.[/quote]
Actually, those got very high scores from a few people, even compared to L18. It seems there is no definite concensus which driver is a clear winner.
On paper, the Dayton might be even better for monitoring, as it does not have that 4db peak around 850Hz. If you try to actively cross it around 2K you might get away with those "camel back" peaks on 6.2K and 10db on 9K, even without notch.
Most definitely, the price is right.
Consul
Well-known member
And I have something special in mind for that specific driver, as soon as I can figure out why the freaking maths aren't working out correctly.
Consul
Well-known member
Well, I think I'm as ready as I'll ever be to reveal my design proposal. First off, I would like to give a huge thanks to Robert C. White from the ESP forums, without whom I would be even more lost than I am now.
My plan is to use the Dayton RS150S-8 shielded in a vented alignment called the 5th Order Quasi-Butterworth. The aforementioned Mr. White wrote a nice article about it, available here (definitely read this before continuing):
http://sound.westhost.com/qb5align.htm
In a nutshell, the idea is to tune the box in such a way that you get a nice hump at the lower roll-off point, which is then corrected by an active filter (he gives all the details in the article). The net result of this is a higher net output of the driver with lower distortion, at the expense of needing a larger box for a typical vented application, as well as a small reduction in transient response. How much remains to be seen, but given the cost of these drivers, the experiment won't cost too much.
Here's the WinISD plot for this driver in a QB5-II alignment (click on thumbnail to open):
Nice little 2.55dB hump there, doncha think? :wink: Here are the values for the correction filter referenced in Robert's article (I would greatly appreciate it if someone could re-check the math for me):
C1 and C2: 100nF
R1 and R2: 25.6k
R4: 10k
R3: 4.4k
Not all of those are readily-available values, but it's possible to get "close enough" or otherwise serial/parallel several resistors to get more precise.
If my calculations and simulations are correct, this will lead to a pair of monitors with a lower -3dB point of about 55-57hz, which isn't the greatest, but may be adequate for small rooms. It does make for a possible good mate for a subwoofer, though. For that, I'm thinking the Dayton RS270S-8 10" woofer. I'm still unsure on whether I want to go for a pair of subs, perhaps even integrated into the same cabs, or a single center sub. I still need to run some sims on this driver to see how well-behaved I can make it.
That's about all for now. Feel free to direct all comments, criticisms, and requests to have me committed later on in this thread.
My plans for the future involve working out a final idea for the subwoofer, and then hopefully simulating all of this in something better/more thorough.
PS -- For the tweeter, I'm pretty well set on the Seas 27TBFCG. There must be a reason this tweeter and it's soft-domed cousin have become the go-to choice for so many speaker DIYers out there...
My plan is to use the Dayton RS150S-8 shielded in a vented alignment called the 5th Order Quasi-Butterworth. The aforementioned Mr. White wrote a nice article about it, available here (definitely read this before continuing):
http://sound.westhost.com/qb5align.htm
In a nutshell, the idea is to tune the box in such a way that you get a nice hump at the lower roll-off point, which is then corrected by an active filter (he gives all the details in the article). The net result of this is a higher net output of the driver with lower distortion, at the expense of needing a larger box for a typical vented application, as well as a small reduction in transient response. How much remains to be seen, but given the cost of these drivers, the experiment won't cost too much.
Here's the WinISD plot for this driver in a QB5-II alignment (click on thumbnail to open):
Nice little 2.55dB hump there, doncha think? :wink: Here are the values for the correction filter referenced in Robert's article (I would greatly appreciate it if someone could re-check the math for me):
C1 and C2: 100nF
R1 and R2: 25.6k
R4: 10k
R3: 4.4k
Not all of those are readily-available values, but it's possible to get "close enough" or otherwise serial/parallel several resistors to get more precise.
If my calculations and simulations are correct, this will lead to a pair of monitors with a lower -3dB point of about 55-57hz, which isn't the greatest, but may be adequate for small rooms. It does make for a possible good mate for a subwoofer, though. For that, I'm thinking the Dayton RS270S-8 10" woofer. I'm still unsure on whether I want to go for a pair of subs, perhaps even integrated into the same cabs, or a single center sub. I still need to run some sims on this driver to see how well-behaved I can make it.
That's about all for now. Feel free to direct all comments, criticisms, and requests to have me committed later on in this thread.
My plans for the future involve working out a final idea for the subwoofer, and then hopefully simulating all of this in something better/more thorough.
PS -- For the tweeter, I'm pretty well set on the Seas 27TBFCG. There must be a reason this tweeter and it's soft-domed cousin have become the go-to choice for so many speaker DIYers out there...
Consul
Well-known member
And as usual, something throws a monkey-wrench into the works. I'm now back to having the basement for my studio, which is good news for everything except this project, because it means that I can now plan for an in-wall mounted design like I had originally wanted to do. I'm still planning on going with the QB5 alignment, only now, A) I don't need any baffle-step compensation, a B) I can consider running 10" Daytons on each side as a stereo sub. The space, I think, is just big enough to accommodate such a three-way system.
This may become a project with several variations. Stay tuned...
This may become a project with several variations. Stay tuned...
Svart
Well-known member
wondering what happened to this..
I still want to build something like this.. I'm thinking a kit from Madisound, maybe the coaxial one.. something with at least 8" woofer or bigger.
I still want to build something like this.. I'm thinking a kit from Madisound, maybe the coaxial one.. something with at least 8" woofer or bigger.
jaygunn
Active member
Apologise if this is slightly off topic...
I read a comment in favor of metal cones in this thread, and it rminded meof this article comparing cone materials by an eccentric, maybe controversial, but sharp designer:
http://www.vmpsaudio.com/d-cones.htm
Hint: He argues in favor of graphite.
John
I read a comment in favor of metal cones in this thread, and it rminded meof this article comparing cone materials by an eccentric, maybe controversial, but sharp designer:
http://www.vmpsaudio.com/d-cones.htm
Hint: He argues in favor of graphite.
John
Svart
Well-known member
anything that will not bend and flex when moving should work fine. metal is the cheapest and lightest choice for a fully rigid cone but graphite and carbon fiber would work too.
And I remember when you stuck some speakers in a box and that was it!
And I remember when you stuck some speakers in a box and that was it!
Svart
Well-known member
http://www.lipinskisound.com/l707.aspx
are those the same as:
http://www.madisound.com/catalog/product_info.php?products_id=1125
+
http://www.madisound.com/catalog/product_info.php?cPath=45_229_250&products_id=1181
??
are those the same as:
http://www.madisound.com/catalog/product_info.php?products_id=1125
+
http://www.madisound.com/catalog/product_info.php?cPath=45_229_250&products_id=1181
??
burdij
Well-known member
and with this cabinet?:
http://www.seas.no/odin_mk3.htm
http://www.seas.no/odin_mk3.htm
Svart
Well-known member
their cabinet looks different but I bet it's the same general design..
now all we need is the crossover.. the lipinski ones are passive..
now all we need is the crossover.. the lipinski ones are passive..
[quote author="Svart"]their cabinet looks different but I bet it's the same general design..
now all we need is the crossover.. the lipinski ones are passive..[/quote]
Sorry Lipinski design is sealed. This one is rear ported. General design is not the same, it's opposite
BTW, drivers are almost the same , if you forget about hand selected pairs :wink:
Also, time aligned drivers and tweeter surrounded with absorption material is very important part of the design. Did you ever listened non aligned design compared to the aligned. I played with that and found that it's really important part of proper design. :thumb: Must be honest, aligned suffer from edge diffraction , non aligned is phase distorted in the critical region 1-5khz :? Best solution (if you are not allergic on digital DSP) is DSP crossover with fine delay correction. :thumb:
now all we need is the crossover.. the lipinski ones are passive..[/quote]
Sorry Lipinski design is sealed. This one is rear ported. General design is not the same, it's opposite
BTW, drivers are almost the same , if you forget about hand selected pairs :wink:Also, time aligned drivers and tweeter surrounded with absorption material is very important part of the design. Did you ever listened non aligned design compared to the aligned. I played with that and found that it's really important part of proper design. :thumb: Must be honest, aligned suffer from edge diffraction , non aligned is phase distorted in the critical region 1-5khz :? Best solution (if you are not allergic on digital DSP) is DSP crossover with fine delay correction. :thumb:
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