Hello everyone
I have recently been in contact with Mr. Rullit regarding his exceptional field-coil drivers, and I intend to place an order for the nine-inch “Super Aero” model in the near future. At present, I am in the process of researching which type of speaker enclosure would best complement these drivers. However, I must note that my options are somewhat limited due to certain non-negotiable constraints—most notably, I am unable to accommodate large horn systems.
To provide some context: I reside in a historic manor apartment, where my dedicated listening room measures approximately 25 square meters (5 × 5 meters), with ceilings reaching a height of 2.7 meters. My musical preferences primarily include classical and jazz repertoire, ranging from solo performances to chamber ensembles and full orchestral works. As an amateur pianist, I place a high value on natural sound reproduction—one that conveys holographic depth, dimensionality, and body, while offering a rich and organically pure tonal character. From my impressions, Rullit’s drivers seem to embody these qualities remarkably well, particularly in terms of transient speed and natural timbre. The sound is airy but has body, it is transparent but has character, it is neutral but has depth. In order words it has the emotional realism that I strive for.
As mentioned in my introductory post, I am quite new to DIY audio projects. However, I have allied with skilled people —one of whom has experience with CNC machining, and another who excels in veneering speaker cabinets with real wood finishes.
From my conversations with knowledgeable individuals, it appears that Rullit drivers are well-suited to a variety of enclosure types, including dipole, front-loaded horn, open baffle, and resonant designs. Personally, I am inclined toward dipole or resonant enclosures, primarily due to their more manageable size. Unfortunately, I believe my room is too small to accommodate horn systems effectively, and open baffle designs would require substantial space behind the speakers, which is impractical given my current interior layout. I have attached photos of possible solutions.
I would be most grateful for guidance and recommendations that could assist me as I move forward with this project. Even specific design plans would be perfect! Any reflections, suggestions, or insights would be sincerely appreciated.
Thank you very much for your time and considerations
I have recently been in contact with Mr. Rullit regarding his exceptional field-coil drivers, and I intend to place an order for the nine-inch “Super Aero” model in the near future. At present, I am in the process of researching which type of speaker enclosure would best complement these drivers. However, I must note that my options are somewhat limited due to certain non-negotiable constraints—most notably, I am unable to accommodate large horn systems.
To provide some context: I reside in a historic manor apartment, where my dedicated listening room measures approximately 25 square meters (5 × 5 meters), with ceilings reaching a height of 2.7 meters. My musical preferences primarily include classical and jazz repertoire, ranging from solo performances to chamber ensembles and full orchestral works. As an amateur pianist, I place a high value on natural sound reproduction—one that conveys holographic depth, dimensionality, and body, while offering a rich and organically pure tonal character. From my impressions, Rullit’s drivers seem to embody these qualities remarkably well, particularly in terms of transient speed and natural timbre. The sound is airy but has body, it is transparent but has character, it is neutral but has depth. In order words it has the emotional realism that I strive for.
As mentioned in my introductory post, I am quite new to DIY audio projects. However, I have allied with skilled people —one of whom has experience with CNC machining, and another who excels in veneering speaker cabinets with real wood finishes.
From my conversations with knowledgeable individuals, it appears that Rullit drivers are well-suited to a variety of enclosure types, including dipole, front-loaded horn, open baffle, and resonant designs. Personally, I am inclined toward dipole or resonant enclosures, primarily due to their more manageable size. Unfortunately, I believe my room is too small to accommodate horn systems effectively, and open baffle designs would require substantial space behind the speakers, which is impractical given my current interior layout. I have attached photos of possible solutions.
I would be most grateful for guidance and recommendations that could assist me as I move forward with this project. Even specific design plans would be perfect! Any reflections, suggestions, or insights would be sincerely appreciated.
Thank you very much for your time and considerations
Attachments
It's a shame that my initial post has not yet received any responses yet. Nonetheless, I hope that someone might be willing to share their perspective.
After some consideration, I believe I will return to my original idea of pursuing an open baffle design. While this approach comes with certain limitations, I feel the most important step is to proceed with acquiring the Rullit driver. Once in hand, I will have access to one of the finest drivers available, which is an exciting prospect.
I'm still fairly new in "hi-fi", I often find myself reflecting on the direction of this project—and occasionally, I do have moments of doubt. Perhaps some context will help. I recently discussed the idea of upgrading my current entry-level Audio Note (AN D/J) speakers to a higher-tier model (AN E SPe/HE) with a friend. However, he advised against it, suggesting that I could achieve significantly better performance for a fraction of the cost by building a system myself. I believe this is a valid point.
Of course, purchasing speakers from a reputable and established brand like Audio Note means you are also paying for their name, legacy, and craftsmanship—not just the raw components or labor. Yet it still feels somewhat implausible to me that a DIY speaker could truly rival their offerings. I suppose my concern is whether this project might turn into an endless cycle of experimentation and adjustments without reaching a satisfying result.
While I understand many enthusiasts enjoy the process of testing different drivers and configurations, my personal aim is to arrive at a well-integrated, long-term solution and lasting upgrade—rather than a stepping stone in an ongoing series of changes.
These are simply my thoughts, and I would be very interested to hear your insights and experiences related to similar projects.
On a lighter note, I input some room measurements and dimensions into ChatGPT last night—admittedly after a glass or two of wine—and found the suggested open baffle configuration quite interesting. I’d be curious to hear your opinions on that as well.
Height 115 cm
Width 70 cm
Thickness 21 mm (front baffle)
Driver cutout Ø 225 mm, centeret at 62 cm height
Side wings 26 cm deep, angled a ~30°
Stand height 15 cm off the floor
Rear wall distance ≥ 1.2 m (minimum)
Rationale:
Front baffle:
Spruce (European or Sitka): 21 mm thick
15 mm spruce core + 6 mm maple face veneer
Side wings
Baltic birch ply or Beech, 21 mm
Base stand
Hardwood (ash, oak, mahogny), 15 cm
Damping
1 thin layer of sheep’s wool mounted 15-20 cm behind the driver
Suspended on a horizontal dowel or hoop, not glued.
After some consideration, I believe I will return to my original idea of pursuing an open baffle design. While this approach comes with certain limitations, I feel the most important step is to proceed with acquiring the Rullit driver. Once in hand, I will have access to one of the finest drivers available, which is an exciting prospect.
I'm still fairly new in "hi-fi", I often find myself reflecting on the direction of this project—and occasionally, I do have moments of doubt. Perhaps some context will help. I recently discussed the idea of upgrading my current entry-level Audio Note (AN D/J) speakers to a higher-tier model (AN E SPe/HE) with a friend. However, he advised against it, suggesting that I could achieve significantly better performance for a fraction of the cost by building a system myself. I believe this is a valid point.
Of course, purchasing speakers from a reputable and established brand like Audio Note means you are also paying for their name, legacy, and craftsmanship—not just the raw components or labor. Yet it still feels somewhat implausible to me that a DIY speaker could truly rival their offerings. I suppose my concern is whether this project might turn into an endless cycle of experimentation and adjustments without reaching a satisfying result.
While I understand many enthusiasts enjoy the process of testing different drivers and configurations, my personal aim is to arrive at a well-integrated, long-term solution and lasting upgrade—rather than a stepping stone in an ongoing series of changes.
These are simply my thoughts, and I would be very interested to hear your insights and experiences related to similar projects.
On a lighter note, I input some room measurements and dimensions into ChatGPT last night—admittedly after a glass or two of wine—and found the suggested open baffle configuration quite interesting. I’d be curious to hear your opinions on that as well.
Height 115 cm
Width 70 cm
Thickness 21 mm (front baffle)
Driver cutout Ø 225 mm, centeret at 62 cm height
Side wings 26 cm deep, angled a ~30°
Stand height 15 cm off the floor
Rear wall distance ≥ 1.2 m (minimum)
Rationale:
- Slightly wider baffle gives you deeper bass support (~80–90 Hz before rolloff
- Taller height raises soundstage and balances your 2.7 m ceiling
- 25 cm angled wings increase rear wave path length, extending bass further
Front baffle:
Spruce (European or Sitka): 21 mm thick
15 mm spruce core + 6 mm maple face veneer
Side wings
Baltic birch ply or Beech, 21 mm
Base stand
Hardwood (ash, oak, mahogny), 15 cm
Damping
1 thin layer of sheep’s wool mounted 15-20 cm behind the driver
Suspended on a horizontal dowel or hoop, not glued.
You need T/S parameters and just calculate a normal speaker alignment.
Just a straight forward floor standing tower.
It will actually have bass.
Chat GPT is a waste of time for speaker design, it makes up nonsense.
Use standard calculations with WinIsd or VirtuixCad
Just a box with bracing with correct volume. very basic math
Port area and length for needed tuning.
Just a straight forward floor standing tower.
It will actually have bass.
Chat GPT is a waste of time for speaker design, it makes up nonsense.
Use standard calculations with WinIsd or VirtuixCad
Just a box with bracing with correct volume. very basic math
Port area and length for needed tuning.
Last edited:
I do not have T/S parameters. Mr. Rullit doesn't share the technical data and I will respect that. After all it is his creation.
I just used ChatGPT for fun - I hope that came out clear in my post.
I have no experience with WinIsd or VirtuixCad. Can you elaborate? Which type of cabinet do you recommend for the Rullit?
I just used ChatGPT for fun - I hope that came out clear in my post.
I have no experience with WinIsd or VirtuixCad. Can you elaborate? Which type of cabinet do you recommend for the Rullit?
https://www.clinamenaudio.com/ep-1134-atelier-rullit-aero-9-
I don't think this is a job for a beginner. The idea of buying drivers and putting them in a box, and that honey and milk will flow out of them, is not realistic. I assume that it is not a small investment.
The only thing acceptable in this case is a verified project for that driver.
I don't think this is a job for a beginner. The idea of buying drivers and putting them in a box, and that honey and milk will flow out of them, is not realistic. I assume that it is not a small investment.
The only thing acceptable in this case is a verified project for that driver.
Last edited:
After we see frequency response data and T/S parameters.
( likely not)
It is really cool what was done, but bake lite spiders and leather surrounds sounds like
waste of money.
Frequency response data would show use the holographic organic deep distortion.
No bass dipole
For hundred dollars get a 8" Tang band or Dayton wideband.
80 years of material and design improvement can be yours.
My last field coil was included with the cabinet and radio.
Including all the tubes. 50 dollars
15"
( likely not)
It is really cool what was done, but bake lite spiders and leather surrounds sounds like
waste of money.
Frequency response data would show use the holographic organic deep distortion.
No bass dipole
For hundred dollars get a 8" Tang band or Dayton wideband.
80 years of material and design improvement can be yours.
My last field coil was included with the cabinet and radio.
Including all the tubes. 50 dollars
15"
I appreciate your responses. Thank you.
I was thinking the same thing although I have already allied with skilled people to support me with the technical and practical tasks that this project imply. Can you please elaborate on eventual faux pas, blunders etc.?
I was thinking the same thing although I have already allied with skilled people to support me with the technical and practical tasks that this project imply. Can you please elaborate on eventual faux pas, blunders etc.?
The main thing is a suitable box and power supply for that driver. The rest is less important. Unfortunately, there is no technical data, recording of the frequency range, impedance and TS parameters anywhere. With that driver, some TS parameters change with the current of the electromagnetic coil. Everywhere only unprofessional comments and enthusiasm for the sound. The practice is for the manufacturer to provide that information, there is none here. The drivers look DIY which they basically are. I think there are better speakers for that money for sure. What you expect from a speaker is what we all want more or less. This can be achieved in various ways.
Last edited:
Thank you for your message. This is quite interesting. It seems to me that drivers of Rullit are praised to the skies for their extraordinary natural timbre, their organic tonal palette and the vividly holographic soundstage.
Is it really impossible to design a speaker cabinet without the parameters? I will have to purchase it first, measure it myself and then do the calculations...
Ay way . Get the Dayton woofer tester and measure TS parameters if you're inclined to know them . While a narrow tower like box might ( or may not ) help with " holography " it's usually a disaster in tone and body so wide and ugly boxes would be my bet. Not sharing TS parameters by a driver manufacturer is like refusing to provide the tire size by manufacturer of a car. Total nonsense. Personally I'd put them in biggest box the room can tolerate and call it a day.
If you want to join a club of " properly designed speakers " which although properly designed usually end up in a closet or on the street a month later to make room for another properly designed ( but even more properly ) than follow the constant stream of poplars and graphs and chose the one which is the most colorful and pretty 🙂
If you want to join a club of " properly designed speakers " which although properly designed usually end up in a closet or on the street a month later to make room for another properly designed ( but even more properly ) than follow the constant stream of poplars and graphs and chose the one which is the most colorful and pretty 🙂