Hi,
Is there any advantage of a horned compression driver for the trebles at an average civilsated listening volume of 75/80 db spl ? (domestic environment)
Does the compression driver/horn combo winns on some trade offs like :
better micro dynamic over a ribbon/esl/planar or dome tweeters ? Or better macro dynamic (huge spl difference between two notes)
Less distorsion when dynamic occurs (increase of SPL during peaks demands)
Or just different patterns between the types of transducters due to their shapes and/or hability to have less stress in their low end (XO cut choose) ? So more a choice because the room (size, sound balance) ?
We often read than ribbon owners find their tweeter is the nearest from the reality, is it all about the average spl volume we play at home ? Question is not inocent (or maybe it is ?!) as for instance for the same low average volume, compresson drivers will need more attenuation, i.e. greater résistor values (more distorsion ?).
But the trade offs of your amp (sensibility of the speaker as a choice factor for the amp), what gave you the best results for trebles (> 1500 Hz)
I'm often surprised to see than ribons owners, dome owners, compression drivers owners seem almost unreconcilable ?!
Is there any advantage of a horned compression driver for the trebles at an average civilsated listening volume of 75/80 db spl ? (domestic environment)
Does the compression driver/horn combo winns on some trade offs like :
better micro dynamic over a ribbon/esl/planar or dome tweeters ? Or better macro dynamic (huge spl difference between two notes)
Less distorsion when dynamic occurs (increase of SPL during peaks demands)
Or just different patterns between the types of transducters due to their shapes and/or hability to have less stress in their low end (XO cut choose) ? So more a choice because the room (size, sound balance) ?
We often read than ribbon owners find their tweeter is the nearest from the reality, is it all about the average spl volume we play at home ? Question is not inocent (or maybe it is ?!) as for instance for the same low average volume, compresson drivers will need more attenuation, i.e. greater résistor values (more distorsion ?).
But the trade offs of your amp (sensibility of the speaker as a choice factor for the amp), what gave you the best results for trebles (> 1500 Hz)
I'm often surprised to see than ribons owners, dome owners, compression drivers owners seem almost unreconcilable ?!
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It's often a matter of freq. range.
(..there are of course operational reasons for each preference with objective results.)
Subjectively in general:
The lower the mms AND mechanical damping (particularly the surround), the greater the apparent detail.
HOWEVER,
With lower mms you end-up with lower force/"dynamics" and "imaging" that is less "3D" (..though this depends quite a lot on how the amplifier works with the driver and crossover components - if any).
You'll often see enthusiasts that are using compression drivers for upper-mid lower treble, also using (crossing-over to) Ribbons/Electrostats/Heil-AMT for the upper treble range. Part of this is often to increase the pressure off-axis horizontally (..assuming they aren't horn-loaded as well), BUT it's also done to improve detail reproduction. The compression driver in-turn generally provides more "body" and "dynamics" in the upper midrange and lower treble (irrespective of amplifier) while NOT providing the last "word" on apparent detail at higher freq.s.
Freq. range is a huge factor for any given design (both objectively and subjectively). When you say something like >1500 Hz I automatically think dome tweeter (..and it's really more like >2000 Hz).
(..there are of course operational reasons for each preference with objective results.)
Subjectively in general:
The lower the mms AND mechanical damping (particularly the surround), the greater the apparent detail.
HOWEVER,
With lower mms you end-up with lower force/"dynamics" and "imaging" that is less "3D" (..though this depends quite a lot on how the amplifier works with the driver and crossover components - if any).
You'll often see enthusiasts that are using compression drivers for upper-mid lower treble, also using (crossing-over to) Ribbons/Electrostats/Heil-AMT for the upper treble range. Part of this is often to increase the pressure off-axis horizontally (..assuming they aren't horn-loaded as well), BUT it's also done to improve detail reproduction. The compression driver in-turn generally provides more "body" and "dynamics" in the upper midrange and lower treble (irrespective of amplifier) while NOT providing the last "word" on apparent detail at higher freq.s.
Freq. range is a huge factor for any given design (both objectively and subjectively). When you say something like >1500 Hz I automatically think dome tweeter (..and it's really more like >2000 Hz).
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Wow, quite interresting !
I understood something near but without enough experience to abstract any conclusion. There is too much dependancies between the stuffs which are often designed standalone. Which push us to tweaking to make our mixed devices sounding more coherent.
I see a great, avenir, futur, for the whole designed stuffs : daced, Amped speakers ! It will talk more about brands capabilities and savoir-faire, but at least less liberty in our hobby.
If this time, taking a standalone dome driver above 2000 Hz (you are true, so few can be crossed lower), dome should be a winner taking all the trade offs (less filter and passive parts) or regarding just the sounding result : does a mix of drivers could subjectivly a greater accuracy like your good illustration of mixing several technologies where they are the most likely to sucess. For instance here the ribbons above 8K/10K Hz and Something else at the bottom where a different patern and more air needs to be moved ?
Of course difficult conversation (at least for me) as : there are topologies as you said : amps, passive parts or not...
In the real world i know few brands who are making with success a whole great hifi system from A to Z; maybe Bang&Olufsen, but mixed combinations seem to go further in sound quality !
Maybe my question was bad, it's maybe bad to beginn from a particular device (here the tweeter) to targett a holystic result (sound reproduction) because the dependencies you pointed out ?! I did management project, but there are so much subjects and different knwoledge areas about hifi reproduction than the task seems often...dificult (very) in relation to the result (having Something sounding musical and right enough in non standardized listening rooms)!
I understood something near but without enough experience to abstract any conclusion. There is too much dependancies between the stuffs which are often designed standalone. Which push us to tweaking to make our mixed devices sounding more coherent.
I see a great, avenir, futur, for the whole designed stuffs : daced, Amped speakers ! It will talk more about brands capabilities and savoir-faire, but at least less liberty in our hobby.
If this time, taking a standalone dome driver above 2000 Hz (you are true, so few can be crossed lower), dome should be a winner taking all the trade offs (less filter and passive parts) or regarding just the sounding result : does a mix of drivers could subjectivly a greater accuracy like your good illustration of mixing several technologies where they are the most likely to sucess. For instance here the ribbons above 8K/10K Hz and Something else at the bottom where a different patern and more air needs to be moved ?
Of course difficult conversation (at least for me) as : there are topologies as you said : amps, passive parts or not...
In the real world i know few brands who are making with success a whole great hifi system from A to Z; maybe Bang&Olufsen, but mixed combinations seem to go further in sound quality !
Maybe my question was bad, it's maybe bad to beginn from a particular device (here the tweeter) to targett a holystic result (sound reproduction) because the dependencies you pointed out ?! I did management project, but there are so much subjects and different knwoledge areas about hifi reproduction than the task seems often...dificult (very) in relation to the result (having Something sounding musical and right enough in non standardized listening rooms)!
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Well, a *good* dome tweeter generally provides a better subjective result with a crossover in that all important operating freq. range of 1-7.5 kHz. (..with a crossover typically between 1800 and 2800 Hz - usually depending on how steep the high-pass filter is for the tweeter.) ..and this is with respect to normal input-levels/domestic use.
Getting a truly fantastic result however, often involves other technologies.
Ex. (compression driver vs. dome)
A really nice large format aluminum compression driver (3" with 2" exit) between about 800 Hz and 5 kHz with the right type of waveguide *can* substantively improve (subjectively) on what a *good* tweeter can provide. (..it can also improve some characteristics of objective quality as well like non-linear distortion, though other objective qualities can suffer as well.) BUT it can also be a royal pain trying to get good integration with superior super-tweeter (..and not necessarily easy getting good integration with the lower midrange driver either).
Despite that, a really excellent dome tweeter(s) in an unusual configuration might still exceed that subjectively over the same freq. range.
-It really depends on the design.
IMO though, I would generally NOT choose a compression driver - at least not unless I needed really high output (..which really isn't "Hifi"), or extreme efficiency (..*over* 100db at 1 watt).
Even if I needed good efficiency (a bit less than 100 db), I'd look to other design choices (..like maybe an array of dome tweeters in combination with an efficient ribbon super tweeter - even though I'd loose some of that force/"dynamic" sound).
Getting a truly fantastic result however, often involves other technologies.
Ex. (compression driver vs. dome)
A really nice large format aluminum compression driver (3" with 2" exit) between about 800 Hz and 5 kHz with the right type of waveguide *can* substantively improve (subjectively) on what a *good* tweeter can provide. (..it can also improve some characteristics of objective quality as well like non-linear distortion, though other objective qualities can suffer as well.) BUT it can also be a royal pain trying to get good integration with superior super-tweeter (..and not necessarily easy getting good integration with the lower midrange driver either).
Despite that, a really excellent dome tweeter(s) in an unusual configuration might still exceed that subjectively over the same freq. range.
-It really depends on the design.
IMO though, I would generally NOT choose a compression driver - at least not unless I needed really high output (..which really isn't "Hifi"), or extreme efficiency (..*over* 100db at 1 watt).
Even if I needed good efficiency (a bit less than 100 db), I'd look to other design choices (..like maybe an array of dome tweeters in combination with an efficient ribbon super tweeter - even though I'd loose some of that force/"dynamic" sound).
On the subject of good tweeters:
http://www.diyaudio.com/forums/mult...ime-afford-tweeter-roundup-3.html#post5060907
http://www.diyaudio.com/forums/mult...ime-afford-tweeter-roundup-3.html#post5060907
A compression tweeter is good for attaching to a waveguide which gives you the pattern you need. The downside is size, cost, setting up including equalising/crossing. Then, they sound the same at very quiet levels as they do loud and this is important.
The way I see it...
- Ribbons tend to be fragile and light-weight. They'll extend very well past 20kHz, but tend to suffer if driven low or loud due to their very limited Xmax
- Compression drivers are happy going loud and (if their design allows) often quite low. The ones that go low will get ragged above 10kHz, though.
- Domes are, IMO, a happy medium. They'll usually get to 20kHz just fine, and some of them will go pretty low.
There are sub-sets like ring-radiators and AMTs, but I'll leave it up to the reader to figure out where they sit.
Chris
- Ribbons tend to be fragile and light-weight. They'll extend very well past 20kHz, but tend to suffer if driven low or loud due to their very limited Xmax
- Compression drivers are happy going loud and (if their design allows) often quite low. The ones that go low will get ragged above 10kHz, though.
- Domes are, IMO, a happy medium. They'll usually get to 20kHz just fine, and some of them will go pretty low.
There are sub-sets like ring-radiators and AMTs, but I'll leave it up to the reader to figure out where they sit.
Chris
It's typically the phase plug that causes a ragged response. A larger driver could have a phase plug that works to 20k. Larger drivers can be less useful due to lower efficiency at the top end, but a 1" compression driver can cover from above 10k to below 1k in a domestic situation. Below this is less critical and more tolerant of a crossover arrangement, probably making things easy enough to call it, IMO.
If only looking at dispersion:
- Soft domes have both wide (180 deg) horizontal and vertical dispersion but they narrow above ~5 kHz. This is because at those high frequencies, the centre and circumference of the dome do not move in phase any more. Ring radiators exhibit approximately the same dispersion pattern.
- Hard domes can hold their wide (180 deg) dispersion up to a slightly higher frequency than soft domes, as their domes move in phase up to above 20 kHz.
- Ribbons usually are narrow, so they have the same wide (180 deg) horizontal dispersion as domes. As they usually are tall, they have a narrow vertical dispersion, which decreases as frequency goes up. Some people say that a wide horizontal and small vertical dispersion is good. If I understand the book 'Sound Reproduction' by Floyd Toole correctly, this is because lateral reflections add spaciousness, while reflections coming from above and below do not add much of this. Floyd Toole however appears to favour a constant beam width. As for why some people like narrow vertical dispersion: my own interpretation is that reflections coming from above and below decrease clarity.
- Dispersion of compression drivers is determined by the horn, which can be anything. Usually horn designers strive for constant horizontal beam width and either constant or decreasing (with increasing frequency) vertical beam width.
Compression drivers indeed require a lot of padding. Resistors are close to perfect in loudspeaker applications, so fortunately this does not add a significant amount of distortion if you do it after the amplifier.
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I thought it was the 3" diaphragm going into breakup modes above 10kHz. It'd explain why aluminium diaphragms measure differently to titanium, phenolic, beryllium etc etc.
Chris
I readed a surprising comment of a monitor without serie resistor (HumbleHome made hifi) was "sounding" better in the filter !
It's a good thing to know (post above) that increasing the value of a serie resistor with a tweeter is a non issue. I believed for instance no resistor or a little value of 1 ohm gave less damaging than a 20 ohms because thermal issues. Glad to hear that the signal is "strong" enough to not be impacted by the voltage attenuation at ears .
It's a good thing to know (post above) that increasing the value of a serie resistor with a tweeter is a non issue. I believed for instance no resistor or a little value of 1 ohm gave less damaging than a 20 ohms because thermal issues. Glad to hear that the signal is "strong" enough to not be impacted by the voltage attenuation at ears .
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I believe that dilemma domes over compression drivers is mostly a question od one's taste in these matters. Both of these worlds, when optimally designed, can be very satisfactory in respect to sound quality, subjective bias put aside. My opinion is that domes can never substitue PA technology when it comes to the specific use of covering the large spaces with high spl. My basic needs for spl are very modest. I have said it once already and I'll repeat it again. 83 dB/2,83V/1m speaker sensitivity and 10W/8ohm power amp. I do own equipment exceeding these figures but I never or very very rarely use its total capabilities. I would hate to break my high resolution speakers for a stupid reason like throwing a party or whatever. In that case I'd rather rent pro stuff, capable of withstanding intoxicated men messing with the volume pot.
-remember though, you can do the same thing with a dome tweeter - and often get a better result (both objectively and subjectively).
(..and done so with less expense, though more effort in designing/producing the right waveguide profile for the dome tweeter. The equalization, impedance compensation, and crossover is usually easier than with a typical compression driver.)
As long as you don't go to loud, it will have that similar sound at low and high spl's.
So it's ok in a home environment : average level is not so high, and huge peaks are not so often on the reccordings...
I was hoping a treble compression to have more control on the very dynamic programs (very fast change of spl with many instruments= diferent informations at diferent spl in a very narrow time window) or maybe an ESL... but it seems the whole thing is far more complex : integibility is also a question of radiation patern !
Ok, one must choose the treble driver in relation to the final design and spl needs
I am exactly in the same situation than Lojzek: music at home !
So I assume, it's better to choose the topology around to gain in quality : for instance a dedicated amp for the treble ? (not for active filter reason but for a better control of the driver) ??? Or it doesn't matter ? nno real improvement but just a choice because choosing some confort : DSP, Active EQ, better phase integration with the mid ?
I was hoping a treble compression to have more control on the very dynamic programs (very fast change of spl with many instruments= diferent informations at diferent spl in a very narrow time window) or maybe an ESL... but it seems the whole thing is far more complex : integibility is also a question of radiation patern !
Ok, one must choose the treble driver in relation to the final design and spl needs
I am exactly in the same situation than Lojzek: music at home !
So I assume, it's better to choose the topology around to gain in quality : for instance a dedicated amp for the treble ? (not for active filter reason but for a better control of the driver) ??? Or it doesn't matter ? nno real improvement but just a choice because choosing some confort : DSP, Active EQ, better phase integration with the mid ?
You can achieve a more detailed sound by removing crossover components (particularly passive, and particularly resistance - especially resistance with traditional resistors).
..BUT,
(depending on the amplifier)
-you can achieve a particular type of sound with minimalist (few components) passive crossover, and especially with respect to the signal portion of the tweeter's high-pass (and potentially the high-pass and low-pass of a upper-mid/lower-treble driver). This is that area where capacitor sound "leaks" through, and can benefit or trash the sound.
Ex. cheap Tripath amplifiers are quite good with detail. With an active filter and no signal passive components between the amp and driver can sound particularly detailed.. BUT the overall sound can be characterized as "thin" or "bright" - especially with a driver that is very good with presenting detail. Now well-chosen passive crossover components (particularly cap's) can preserve most of that detail while highlighting apparent imaging - giving a more "rounded" sound. (Ex. TonyGee's Cap Test mentions MR Clarity caps being particularly adept at producing this sort of sound.) So while a designer might want to automatically use an active design to try and extract more detail, it may NOT be the better approach with an amp like the Tripath and a driver that presents a lot of detail on it's own (..worst-case would likely be small planar line tweeter like HiVi or Beston offers).
In any event, the overall design is still the most important factor in the loudspeaker: producing a good linear loudspeaker with good to excellent off-axis behavior (as required by the design, but still reasonably uniform with respect to freq.).
..BUT,
(depending on the amplifier)
-you can achieve a particular type of sound with minimalist (few components) passive crossover, and especially with respect to the signal portion of the tweeter's high-pass (and potentially the high-pass and low-pass of a upper-mid/lower-treble driver). This is that area where capacitor sound "leaks" through, and can benefit or trash the sound.
Ex. cheap Tripath amplifiers are quite good with detail. With an active filter and no signal passive components between the amp and driver can sound particularly detailed.. BUT the overall sound can be characterized as "thin" or "bright" - especially with a driver that is very good with presenting detail. Now well-chosen passive crossover components (particularly cap's) can preserve most of that detail while highlighting apparent imaging - giving a more "rounded" sound. (Ex. TonyGee's Cap Test mentions MR Clarity caps being particularly adept at producing this sort of sound.) So while a designer might want to automatically use an active design to try and extract more detail, it may NOT be the better approach with an amp like the Tripath and a driver that presents a lot of detail on it's own (..worst-case would likely be small planar line tweeter like HiVi or Beston offers).
In any event, the overall design is still the most important factor in the loudspeaker: producing a good linear loudspeaker with good to excellent off-axis behavior (as required by the design, but still reasonably uniform with respect to freq.).
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Main advantages of compression drivers in a wg over a dome tweeters are that they can be cut lower to midbass, they have constant and controlled directivity, they show less strain/less power compression.
The thing i'd like to see is for someone to measure average WG/CD combo (say B&C DE250-8/xt1086), and compare it to a top-notch dome tweeter (one of the Scan Speak Be series or anything from Transducer Labs). I would do it but i can't get my hands on either one of those. I'd really like to see how compression driver behaves regarding distortion at say 90dB compared to dome tweeter.
That would be objective things that can be measured. As for subjective, i've never heard a dome tweeter that comes even close to CD/WG combo, when done right (BMS 4592nd in Oris Swing and DE250 or DE500 in XT1086, JBL PT waveguide and Summa waveguides to be exact). That kind of detail and precision are beyond of what a dome tweeter can do. And those are of the shelf compression drivers. I'd really like to play with compression drivers that's been upgraded with Be diaphragms.
The thing i'd like to see is for someone to measure average WG/CD combo (say B&C DE250-8/xt1086), and compare it to a top-notch dome tweeter (one of the Scan Speak Be series or anything from Transducer Labs). I would do it but i can't get my hands on either one of those. I'd really like to see how compression driver behaves regarding distortion at say 90dB compared to dome tweeter.
That would be objective things that can be measured. As for subjective, i've never heard a dome tweeter that comes even close to CD/WG combo, when done right (BMS 4592nd in Oris Swing and DE250 or DE500 in XT1086, JBL PT waveguide and Summa waveguides to be exact). That kind of detail and precision are beyond of what a dome tweeter can do. And those are of the shelf compression drivers. I'd really like to play with compression drivers that's been upgraded with Be diaphragms.
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I have been using both compression drivers and soft domes many years, but my "current" fav is the horn. Generally, I can say the horn speaker's strength is midrange and weakness is high, and the dome tweeter is the opposite. So I think it's not unreasonable that someone says the ultimate dome system is the one with ATC dome midrange, and the ultimate horn is the big horn + ribbon super tweeter.
PS: And I can say, crossover at ear's most sensitive range, 1k-4k, is a big no-no. I guess many people who prefer horn and fullrange would agree with this.
PS: And I can say, crossover at ear's most sensitive range, 1k-4k, is a big no-no. I guess many people who prefer horn and fullrange would agree with this.
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Waveguide with dome tweeter:
Scan Speak D2604/ 833000 / Waveguides - Techtalk Speaker Building, Audio, Video Discussion Forum
Scan Speak D2604/ 833000 / Waveguides - Techtalk Speaker Building, Audio, Video Discussion Forum
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