I hear what you're saying, and I get the intent—to encourage others to learn and grow in their design skills. That said, it's worth being compassionate to the fact that this is not an easy task for most people to tackle without a significant investment of time, trial and error, and frankly, frustration.
There are very few, if any, well-documented DIY designs out there in the 93–95 dB range that are truly approachable for the average builder. Not everyone is an engineer, or has the skillset, tools, or bandwidth to learn crossover simulation, driver integration, and enclosure tuning from scratch—especially with premium drivers where mistakes get expensive fast.
It's not about hand-holding as much as recognizing the barrier to entry. Sometimes, a proven design or community guidance is the bridge someone needs to gain confidence and eventually develop their own ideas. Enthusiasm for high-efficiency, high-end builds is great—but sharing knowledge accessibly is what turns curiosity into results.
There are very few, if any, well-documented DIY designs out there in the 93–95 dB range that are truly approachable for the average builder. Not everyone is an engineer, or has the skillset, tools, or bandwidth to learn crossover simulation, driver integration, and enclosure tuning from scratch—especially with premium drivers where mistakes get expensive fast.
It's not about hand-holding as much as recognizing the barrier to entry. Sometimes, a proven design or community guidance is the bridge someone needs to gain confidence and eventually develop their own ideas. Enthusiasm for high-efficiency, high-end builds is great—but sharing knowledge accessibly is what turns curiosity into results.
I think there is a disconnect between whats really going on and what you think is going on. I encourage you to start a project thread, describe your goal to the community and entertain the help that is given. If you are looking for a good read this is the olive branch
I hear you and I would be very interested in a kit based on these drivers as well!
I have actually found some, mentioned by another member on this forum in a thread somewhere, and have been contemplating it for a while but can't find any info on it anywhere and so am a bit hesitant:
https://www.ari-acoustics.de/c/opera
@kalasbarnet That's an interesting company. They understand the struggles of synergy between these new Bliesma domes and the need to pair them with "snappy" woofers.
I've come to the conclusion that multiple smaller woofers are much more adaptable to the exceptional capabilities of the domes. Larger woofers are just incapable of keeping up with Bliesma mids. Their bandwidth is simply to large and sensitivity is too high.
In a passive crossover application, the Bliesma drivers need careful filtering of breakup peaks. Without this, the sharp peaks will dominate the sound profile. In my build, I chose to use a pair of M74A per side with one driver running shaded, playing only from 500 - 1.2k with a very shallow variable slope. It basically just loafs around, but matches the other mid exactly in phase. As most of you already guessed, this is a passive design, using minimal crossover. I have nothing against the use of decent quality DSP, but if you're heavily invested in analog (like I am), you'll prefer to do things in the same domain without another conversion step.
These new Bliesma domes have been a game changer IMO and requre a completely different level of attention to detail so the best performance can be extracted from them. Even mechanical mounting has become a critical issue.
I ended up using a pair of high sensitivity midbass drivers to match the M74A level of attack. This is tough to achieve. The range of 150 - 500hz is finicky. The phase tracking has to be dead on perfect as does the amplitude and directivity. The enclosure needs to be inert and the mids decoupled using extra mass.
I chose the T34B tweeter for its lower end capabilities using a second order filter. With a mild WG, it can integrate easily with great flexibility.
I've come to the conclusion that multiple smaller woofers are much more adaptable to the exceptional capabilities of the domes. Larger woofers are just incapable of keeping up with Bliesma mids. Their bandwidth is simply to large and sensitivity is too high.
In a passive crossover application, the Bliesma drivers need careful filtering of breakup peaks. Without this, the sharp peaks will dominate the sound profile. In my build, I chose to use a pair of M74A per side with one driver running shaded, playing only from 500 - 1.2k with a very shallow variable slope. It basically just loafs around, but matches the other mid exactly in phase. As most of you already guessed, this is a passive design, using minimal crossover. I have nothing against the use of decent quality DSP, but if you're heavily invested in analog (like I am), you'll prefer to do things in the same domain without another conversion step.
These new Bliesma domes have been a game changer IMO and requre a completely different level of attention to detail so the best performance can be extracted from them. Even mechanical mounting has become a critical issue.
I ended up using a pair of high sensitivity midbass drivers to match the M74A level of attack. This is tough to achieve. The range of 150 - 500hz is finicky. The phase tracking has to be dead on perfect as does the amplitude and directivity. The enclosure needs to be inert and the mids decoupled using extra mass.
I chose the T34B tweeter for its lower end capabilities using a second order filter. With a mild WG, it can integrate easily with great flexibility.
Not sure I understand this. If the bandwidth is so large, then why don't you use it?
@mbrennwa I meant that as a comparison between the dome mids and typical lower sensitivity bass/mids. The Bliesma M74x dome mids have more useful bandwidth than most cone drivers along with higher sensitivity. The majority of bass/mid drivers often have a surround reflection disturbance right in between their whole useful FR.
I prefer dual M74A mids for my application due to the crossover point I chose. I want the extra headroom in the lower mids but don't need the added upper mid sensitivity running both domes in the same range. The other drivers can't keep up.
I prefer dual M74A mids for my application due to the crossover point I chose. I want the extra headroom in the lower mids but don't need the added upper mid sensitivity running both domes in the same range. The other drivers can't keep up.
Isn't that kind of pointless? Sensitivity of M74 is way higher than any woofer, and so are Spl capabilities.
That's how they seem to be used here too, it's a 3,5-way.
Looking at the marketing data of this speaker I can't figure out if they cross the domes at 220 or 330Hz, both of wich are VERY low. 😮
https://suesskindaudio.de/en/kronos-2
@Jonasz It looks like they cross the mids at 330 hz. The lack of baffle with the second mid enables the lower mid HP along with the 92 dB sensitivity. The woofer would never be able to keep up with even one of the mids having that little baffle area. This in turn helps dispersion. They use the LF enclosure as a WG of sorts to control LF directivity.
I was planning on crossing between 400 - 500 hz having both mids. The extra 6dB from the second mid will help reduce the lower mid excursion requirements, as I was debating whether a large baffle was necessary with 2 mids and that mid HP. There is also some overlapping gain to account for, so the mids could actually be run staggered.
For my needs, the design was to be a shamelessly large dynamic range capable speaker with the ability to deliver almost any transient a human could perceive. I'm referring to more than just music signals, but also natural sounds along with sampled/pre-recorded environmental sounds. If the human ear can tolerate the.dynamic swing, so should also the speaker. This may seem excessive to some of you, but I wanted a system that could deliver these requirements. With a large pair of subwoofers, there should be no issues reaching my goals.
I was planning on crossing between 400 - 500 hz having both mids. The extra 6dB from the second mid will help reduce the lower mid excursion requirements, as I was debating whether a large baffle was necessary with 2 mids and that mid HP. There is also some overlapping gain to account for, so the mids could actually be run staggered.
For my needs, the design was to be a shamelessly large dynamic range capable speaker with the ability to deliver almost any transient a human could perceive. I'm referring to more than just music signals, but also natural sounds along with sampled/pre-recorded environmental sounds. If the human ear can tolerate the.dynamic swing, so should also the speaker. This may seem excessive to some of you, but I wanted a system that could deliver these requirements. With a large pair of subwoofers, there should be no issues reaching my goals.
@piotr z I'm actually aiming for 95 dB/2.8V sensitivity and using the most capable LF drivers I can find. The Eminence KL3012LF are very good, even though they don't have the last word in sensitivity below 60 hz. A pair of these per side after BSC will roughly get me to my goals with large subs and LF room gain.
Not trying to criticize anything, just trying to find the reason. Spending money on two Bliesmas and Eminence, I'd rather go for TD15M-4ohm for sensitivity and cross it higher/make wider baffle.
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You're right about the potential benefit of using two mids, but just to clarify—adding a second identical driver gives you 3 dB of acoustic gain due to the doubling of radiating surface area (assuming they’re playing in phase and close together relative to wavelength). The commonly cited 6 dB gain only applies if your amplifier also doubles its power into the new (halved) load impedance, which is typical for solid-state amps with robust power supplies.
So in practice:
- +3 dB from the second driver itself (acoustical gain),
- +3 dB if your amplifier can supply double the power into the halved impedance (electrical gain),
- Total = 6 dB, but only under the right amp conditions.
As for using 4-ohm loads, I don’t see much advantage in most cases. A 4-ohm tap with a 4-ohm speaker gives you no real benefit over an 8-ohm tap with an 8-ohm speaker. In fact, tube amps generally perform better with higher-impedance loads. And most solid-state amps today have plenty of power, so pushing for lower impedance just to squeeze out more sensitivity doesn’t make much sense—unless you're chasing pro-level SPL or trying to rattle the walls.
Well, yes and no.
If you're talking raw transparency, solid state generally wins. But something like a Marantz Model 9 comes so close to that level of fidelity, it becomes a non-issue—especially when you factor in what tubes can uniquely offer: beautiful, natural second harmonic distortion.
That said, this isn’t a free ride. You need top-tier tubes and an amplifier engineered specifically to let those harmonics shine without added mess. It has to be rock-solid into real-world loads and designed for sonic integrity, not just glow and nostalgia.
So yeah—if you’ve got a properly executed design like a Model 9, you’re not exactly sacrificing fidelity.
If you're running something like a Dynaco MKIII? Hell no.
There are far better options out there. Brands like McIntosh and Audio Research offer that classic tube character with far less hassle—no need for costly restorations or chasing gremlins in vintage gear.
If you're talking raw transparency, solid state generally wins. But something like a Marantz Model 9 comes so close to that level of fidelity, it becomes a non-issue—especially when you factor in what tubes can uniquely offer: beautiful, natural second harmonic distortion.
That said, this isn’t a free ride. You need top-tier tubes and an amplifier engineered specifically to let those harmonics shine without added mess. It has to be rock-solid into real-world loads and designed for sonic integrity, not just glow and nostalgia.
So yeah—if you’ve got a properly executed design like a Model 9, you’re not exactly sacrificing fidelity.
If you're running something like a Dynaco MKIII? Hell no.
There are far better options out there. Brands like McIntosh and Audio Research offer that classic tube character with far less hassle—no need for costly restorations or chasing gremlins in vintage gear.
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@Pegasus123. The explanation I gave referring to 6 dB gain was related to sensitivity (dB/2.83V), not dB/W. There is however a slight gray area to this, as across some of the shared bandwidth of both drivers you end up with some mutual coupling gain, as both drivers are in close vicinity to one another. The gain for this with 2 drivers is less than 3 dB, but its dependent on the WL being reproduced.