• Welcome to ASR. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Midrange dome drivers banned ?

Parts Express has a warehouse full of them. Take your pick. I picked up 24 a few months back for a LS build. Personally, I've always been a fan
but if I had to choose between domes and small planars or ribbons, I'd go with planars, ribbons or both. I've never had an interest in cone
speakers except for the bass and sub-sections of the build.

Infinity used poly domes for years. Still one of my favorite speakers. RS6 for a stand mount or RSIIIbs for a floor standing, that an OK valve amp will
power. I use a MC225 or 240 and they rock with more than enough bass.

I'm listening to RSIIIbs right now with a C20 and MC225. Johnny Cash never sounded better. I think I had 200.00 usd after I paid for the speakers
at a garage sale and they had new Infinity surrounds they never installed. I installed 5 way binding post from PE for another 10-15.00.

I had QLS 1s that were a lot of fun 35-40 years ago. Domes and ribbons if I remember correctly.

Regards.
 
Last edited:
Dayton audio showed off some new domes they're working on at the last speaker competition. It appears somehow no one took a picture of them, they also measurement graphs displayed. They were visually nice domes with what appeared to be a metal dome with dimples like a golf ball. They had a matching tweeter to go with them, overall looked like little bliesma's.
 
Such a midrange dome looks interesting and often has a decent acoustic quality in itself (and many of them are simply not this good as hoped for).

Nevertheless, the disadvantages usually outweigh the advantages when integrated into a loudspeaker design.

In practice, attempts are made to cover the range from, say, 600 Hz to 3 kHz with such a dome, which is usually quite feasible.
The problems begin with the integration of the woofer and tweeter and the effort in the crossover to achieve homogeneous reproduction.

In order to achieve an acceptable compromise for the entire system, the effort involved in using passive crossovers for the basic tuning is very high and involves compromises.

At the latest during the fine-tuning you can see that it is extremely cost-intensive and is difficult to justify for that reason.

Yes, one can argue that in times of DSP and active amping the implementation is easier to do, but that applies primarily to the experienced diy builder, otherwise it would be expensive again.

It is not for nothing that the golden ratio for loudspeaker developers has always been the combination of a 16-18 cm woofer with a 25-28 mm dome in terms of sound quality in relation to the effort. This takes advantage of the natural roll-off of the chassis, which can also be brought into phase (+/+) quite easily in terms of the crossover frequency.
A good developer can achieve a strikingly good step response with 'only' 15% overshoot with relatively little effort, i.e. high efficiency. Try this with a 3 way system and good luck!

Therefor the supposedly better 3-way solution is rarely that convincing, at least with a large dome that only reaches one or two octaves lower than a good tweeter. What the large dome can reproduce more in the midrange is also possible with a good bass-midrange cone, which also has more membrane surface area and better power handling. And while a 18 cm midbass starts beaming around 1 kHz, the speaker cabinet is not as critical as with a wide angle dispersion speaker. And this is a bummer for speaker developers!
You get interference problems around 1 kHz depending on the size of the cabinet front panel and they are very problematic cause there is no real solution to fix this with a regular design. Yes, you can add a waveguide, but then you can use a regular woofer as well !!! Or, the non compromise way, you add midranges left and right to the box to virtually create a endless surface ... but then again, this is very expensive and a pain to handle. Manger did it, I too have ideas for such a speaker, but that's just for fun.

Nevertheless, midrange domes currently seem to be very popular again, especially for so-called studio monitors, which seems to be more of a unique selling point for 'special' equipment to stand out in the market. Unfortunately, these big domes don't really make sense (in the regular market).
 
Last edited:
yo! said:
....
Nevertheless, midrange domes currently seem to be very popular again, especially for so-called studio monitors, which seems to be more of a unique selling point for 'special' equipment to stand out in the market. Unfortunately, these big domes don't really make sense.
Click to expand...

Thanks a lot for your comprehensive comments/inputs.

I assume your points would greatly support and validate advantages of still-amazingly-excellent YAMAHA 8.8 cm vapor-deposited Beryllium midrange dome driver JA-0801 covering wide 500 Hz to 6 kHz (which I still like very much and use in DSP-based multichannel audio system; ref. here)...
 
FWIW, dome mids seem to get so much use in studio-intended speakers because they tend to be 1, really insensitive to short term thermal compression because the voice coil is enormous for the size of the driver (a 3" dome has a voice coil the same diameter as a 12"+ cone for example), 2, very sensitive (most 3" domes I know of are between 95-97dB/2.83V) which allows super high spls without stupid amounts of power input, and 3, vanishingly low distortion in their passband (Neumann, ATC, Bliesma, and Volt all hang around 0.1% THD or lower at 90dB or so, and very few cones can match that).
 
dfuller said:
FWIW, dome mids seem to get so much use in studio-intended speakers because they tend to be 1, really insensitive to short term thermal compression because the voice coil is enormous for the size of the driver (a 3" dome has a voice coil the same diameter as a 12"+ cone for example), 2, very sensitive (most 3" domes I know of are between 95-97dB/2.83V) which allows super high spls without stupid amounts of power input, and 3, vanishingly low distortion in their passband (Neumann, ATC, Bliesma, and Volt all hang around 0.1% THD or lower at 90dB or so, and very few cones can match that).
Click to expand...
No doubt that they're capable producing excellent sound with low distortion.
No doubt you can construct very good sounding speakers with big domes.
I simply showed up, why such domes are rare in the market.

I would prefer regular small cones for a dedicated midrange or flat diaphragm. Why?
Cones are easier to design and produce matching the same quality.
The big fragile voicecoils are PITA in terms of production precision and quality control. Again, it's possible, but questionable to use big domes.

Nevertheless, I LIKE big domes too, I swear :)
 
JeanMiK said:
are there logical/technical reasons to use only cone drivers?
Click to expand...
Yes. https://web.archive.org/web/20010124051200/http://www.dunlavyaudio.com/tech/cones_panel.html

A driver with a circular-shaped cone, suspended at its outer edges by a compliant "surround" and driven at or near its apex by a low-mass voice coil symmetrically immersed in a strong magnetic field, is probably the most accurate type of transducer presently available. The important caveat here, though, is whether it was properly designed, e.g., with: 1. a cone made of materials possessing the right acoustical properties (rigidity, internal-damping, etc.), 2. an outer "surround" with the correct compliance, damping, etc., 3. a voice-coil and magnet structure having an optimum "BL product" (the product of the magnetic flux and length of wire), 4. a spider assembly which properly centers the voice-coil and exhibits correct compliance, damping, etc. and, 5. a frame or basket that is rigid and anti-resonant. Of course, the driver must also exhibit the desired frequency response, impulse response, efficiency, impedance (resistance and reactance Vs frequency), resonant frequency, Qt, Qe, Qm, etc.

Contrary to popular opinion, a dome shaped radiating surface does not provide as wide an operating bandwidth or as wide a beamwidth as a well-designed cone driver having the same diameter. This is partly because the dome is driven from its outer edge, thereby defining the diameter of the radiating area at all frequencies within its operating range. Also, a well-damped dome with a diameter larger than about 2-3 wavelengths at its intended high-frequency limit, e.g. a 3" dome at 10 kHz, usually radiates relatively little energy from its center region - radiation mainly being confined to an annular region surrounding and adjacent to the voice coil. Thus, a dome tends to exhibit the beamwidth properties of a annular (ring-shaped) radiating surface possessing a "constant diameter", with a center region that radiates less energy with increasing frequency. Since the half-power (-3dB) beamwidth (in degrees) of a radiating source is approximately equal to 58/D (where D is the "effective diameter" of the radiating surface, expressed in terms of a wavelength at the frequency being evaluated, e.g., approx. 13,600/freq. in Hertz), a 3 inch dome would exhibit a beamwidth of less than about 26 degrees at 10 kHz. It is interesting to note that an annular-shaped radiating area also tends to exhibit high-level "side lobes" that alternate in phase relative to the main lobe, compared to a more uniformly-illuminated radiating surface.

By contrast, a properly damped, cone-shaped diaphragm, driven by a voice coil located near its apex, experiences a more constant beamwidth over a much wider bandwidth than a dome. This is because properly engineered cone material exhibits "internal damping properties", intended to progressively absorb more energy at higher frequencies. This confines much of it to regions closer to the voice coil.
Thus, while a 3 inch diameter cone type mid-range driver may have an effective radiating diameter of about 2.5 inches at 1 kHz, this probably reduces to less than 1 inch at 10 kHz, yielding a half-power beamwidth of about 80 degrees, nearly 3 times that of a 3 inch dome.

These relative beamwidths, between a 3 inch dome and a 3 inch cone, are only approximate and do not take into account the reduced "velocity-of-propagation" which occurs along or through a "lossy medium", such as a damped diaphragm.

A well-designed cone driver, with optimum damping and flat frequency response, can exhibit an excellent impulse response, with the first "overshoot" approximately minus 15 dB (without crossover). Further "ringing" is typically down more than 20 dB and persists for no more than 100 to 200 microseconds. (A well-designed crossover network can often improve on these values of overshoot and ringing.) Although well-designed dome drivers can also achieve a good impulse-response, they usually exhibit moderately more overshoot and ringing than a well-designed cone driver of the same size and efficiency.

As can be seen, cone and dome drivers typically perform quite differently than most audiophiles believe. While a dome might appear more "hi-tech" than a cone, it has many performance limitations and, for many applications, is inferior (overall) to a cone driver of equal "design quality". As a consequence, domes tend to perform best for tweeter applications, where the diameter of 1 inch dome corresponds to about 1.5 wavelengths at 20 kHz (yielding a half-power beamwidth of about 38 degrees).

An "inverted dome" is generally inferior in performance because the inverted shape forms a "cup-shaped" cavity that can exhibit a resonant property if the depth approaches 1/4 wavelength within the operating range (about 5/32 inch at 20 kHz).

"Jazzy-looking" cone and dome materials (often made from yellow-colored, "bullet-proof" materials, such as Kevlar) usually exhibit poor internal damping properties, resulting in an impulse response characterized by considerable overshoot and subsequent ringing. Kevlar, and similar materials, while providing rigidity, lack proper internal-damping properties required for good impulse response and truly flat frequency/phase response. As a consequence, Kevlar cones (and domes) are generally confined to applications in loudspeaker designs using higher-order crossover responses, where impulse, step and phase responses are not considered important by the designer. Cones and domes made of metal (such as titanium) or ceramic are even worse because these materials provide virtually no internal damping properties, resulting in poor impulse response, poor step response, etc.

While the cones with the best measurable and audible performance may appear to be made of a dark-gray colored "paper" material, they are most likely a complex formulation of felt, cellulose/carbon fibers, a binder, and a coating that provides optimum "damping", minimum formation of undesirable modes at higher frequencies, excellent impulse/step response and very flat frequency/phase response, etc.

Most audiophile-quality cone and dome drivers exhibit a Sound Pressure Level (SPL) of about 88-90 dB, at an on-axis distance of 1 meter, for an input of 1 watt (2.83 volts RMS across 8 ohms). This is many times the efficiency of typical planar diaphragm radiators, having the same radiating area. However, cone and dome drivers with SPL's higher than about 91 dB (re: 1 watt) usually possess a Qts (total Q factor) that yields poor damping and less than good impulse and step responses.
 
Last edited:
Seems like it's written from someone who likes to use low order crossovers, where of course many metal cone drivers would not work, as you aren't filtering the areas with ringing and poor damping.
 
Penelinfi said:
Seems like it's written from someone who likes to use low order crossovers, where of course many metal cone drivers would not work, as you aren't filtering the areas with ringing and poor damping.
Click to expand...
J.D. used domes in the early models of the SC-V, and I own a pair (#117-A/B) and a leter pair with cone upper-mids, #198-A/B. I don't remember much, if anything, about crossovers in his white paper; he simply discussed the advantages and disadvantages of each type of driver.
 
Penelinfi said:
Seems like it's written from someone who likes to use low order crossovers, where of course many metal cone drivers would not work, as you aren't filtering the areas with ringing and poor damping.
Click to expand...
You'd be correct. Dunlavy is well known for using 1st order crossovers for step response reasons.
 
Brent71 said:
J.D. used domes in the early models of the SC-V, and I own a pair (#117-A/B) and a leter pair with cone upper-mids, #198-A/B. I don't remember much, if anything, about crossovers in his white paper; he simply discussed the advantages and disadvantages of each type of driver.
Click to expand...
It seems like some of the adv/disadv is in relation to using such crossovers though? Eg metal drivers
 
Penelinfi said:
It seems like some of the adv/disadv is in relation to using such crossovers though? Eg metal drivers
Click to expand...
Steeper crossover slopes might offset or minimize some of the negative effects of those drivers. It seems like a band-aid way to try to get around the issues the drivers have.
 
That's great, so far, of all the speakers I've listened to, I seem to have quite a few metal driver speakers that are some of my favourite. Will wait for someone to create the perfect driver I guess. I'm surprised I haven't kept for a long time many speakers using low order or no crossover
 
Penelinfi said:
That's great, so far, of all the speakers I've listened to, I seem to have quite a few metal driver speakers that are some of my favourite. Will wait for someone to create the perfect driver I guess. I'm surprised I haven't kept for a long time many speakers using low order or no crossover
Click to expand...
You're free to like whatever you want, it just doesn't mean that it's accurate. The market seems to show that most people prefer speakers that aren't accurate. J.D. showed how to make accurate speakers 30 years ago, and I haven't seen anything since that measures better.
 
Brent71 said:
You're free to like whatever you want, it just doesn't mean that it's accurate. The market seems to show that most people prefer speakers that aren't accurate. J.D. showed how to make accurate speakers 30 years ago, and I haven't seen anything since that measures better.
Click to expand...
There are different kinds of accuracy. Such JD speakers are also considered to be not accurate in some areas. So they aren't perfect by any means.
 
Brent71 said:
You're free to like whatever you want, it just doesn't mean that it's accurate. The market seems to show that most people prefer speakers that aren't accurate. J.D. showed how to make accurate speakers 30 years ago, and I haven't seen anything since that measures better.
Click to expand...

Did you just stop paying attention to speakers for 30 years?
 
Penelinfi said:
There are different kinds of accuracy. Such JD speakers are also considered to be not accurate in some areas. So they aren't perfect by any means.
Click to expand...
Like what? Their impulse response, step response, frequency response and phase response are about perfect.

 
You must log in or register to reply here.

Similar threads

XMechanik
Mini 3-way (7l). f6 ~40Hz. Low distortion in midrange. Recommended PR PIR slopes. Inexpensive drivers and components. (Mechano325)
2
Replies
34
Views
5K
Azrael
Azrael
M
Tweeter Recommendation for Woofer
2
Replies
30
Views
2K
Wolf11Man
W
edc
Questions about taking relevant speaker measurements / spinorama data
Replies
3
Views
768
edc
edc
G
Question about coaxial drivers, directivity vs equalization
2
Replies
31
Views
2K
gorman
G
L
HornResp and Mass Break Point - make it make sense !
Replies
3
Views
467
bmc0
B
Back
Top Bottom