Hi,
do You really think that Hawksford is complicated? Ok, it uses more OPs but if You build around Dual, or Quad-OPs its very simple. OPs are cheap nowadays, but tightly tolerated caps cost and that´s where Hawksford shines, let aside the precision of both passes. And regardless of steepness, the Hogh-Pass-signal jaust passes one OP.
To me thats elegant and simple
Anyway, the classical topologies will probabely be more practical for Your usage ;-)
jauu
Calvin
do You really think that Hawksford is complicated? Ok, it uses more OPs but if You build around Dual, or Quad-OPs its very simple. OPs are cheap nowadays, but tightly tolerated caps cost and that´s where Hawksford shines, let aside the precision of both passes. And regardless of steepness, the Hogh-Pass-signal jaust passes one OP.
To me thats elegant and simple
Anyway, the classical topologies will probabely be more practical for Your usage ;-)
jauu
Calvin
It is not especially complicated conerncing the circuit itself but it needs more time to settle it : I have no PCB construction stuff and hardwire everything on bakelite boards (it's maybe time for me to buy the PCB making stuff 
).
And I don't totally agree on the fact that the signal goes through only one opamp : the other input receives a signal that has gone through the other opamps, and this input interacts with the signal. But maybe what I say is silly !
It looks great indeed and I'll surely give it a try as soon as my electronics skill increases enough
BobEllis : concerning what you say about acoustical rolloff : you say I should adapt the active filter so that its cutoff frequency is the same as the enclosure's ? That sounds great : 24dB for the price of 12
But then, how to calculate the overall Q of this virtual filter ? Is overall Q equal to (first part Q)*(second part Q) or is the formula different ?
For example, is it possible to end with a Q=0.5 24db filter using an enclosure that has a Q of say 0.9 ?
And what about delay ? I have simulated an enclosure with the Fc aligned on both the filter and the enclosure, and an overall Q that I suppose being 0.5. I end up with a 4.3ms delay at Fc. Isn't it enormeous ?! (equivalence of 75cm delay !)
Also, what are really the advantages of a LR alignment ? Isn't the phase of a Butterworth filter symmetrically aligned too ?
Concerning breakup nodes, no problem on this side : I will use "healthy" drivers
Sorry for those noob questions, I'm quite new to crossovers
).And I don't totally agree on the fact that the signal goes through only one opamp : the other input receives a signal that has gone through the other opamps, and this input interacts with the signal. But maybe what I say is silly !
It looks great indeed and I'll surely give it a try as soon as my electronics skill increases enough
BobEllis : concerning what you say about acoustical rolloff : you say I should adapt the active filter so that its cutoff frequency is the same as the enclosure's ? That sounds great : 24dB for the price of 12
But then, how to calculate the overall Q of this virtual filter ? Is overall Q equal to (first part Q)*(second part Q) or is the formula different ?
For example, is it possible to end with a Q=0.5 24db filter using an enclosure that has a Q of say 0.9 ?
And what about delay ? I have simulated an enclosure with the Fc aligned on both the filter and the enclosure, and an overall Q that I suppose being 0.5. I end up with a 4.3ms delay at Fc. Isn't it enormeous ?! (equivalence of 75cm delay !)
Also, what are really the advantages of a LR alignment ? Isn't the phase of a Butterworth filter symmetrically aligned too ?
Concerning breakup nodes, no problem on this side : I will use "healthy" drivers
Sorry for those noob questions, I'm quite new to crossovers
Yep, filters is filters. They don't care whether they are made of electronic parts or a springs and masses. Just multiply them together, which answers your next question. You need an electrical Q of .56 with a box Q of .9 to have an overall Q of .5.
Be sure to measure the actual box cutoff and Q. It could be quite different than predicted. You can use Sallen-Key equal component value topology to allow you to set the Q you want with resistors. Much easier than finding the right capacitors. MFB works, too.
The advantage of L-R alignments is flat response through the crossover region. Butterworth filters will have a bump in response. Again, it's the combination of speaker output and electrical response that matters.
I haven't tried the filter topology that's been suggested (also known as state variable). I have heard that it doesn't sound as clean as Sallen-Key or MFB. However, it could easily just be audiophilia nervosa, knowing that there are all those opamps in the circuit. At least some Marchand XOs use state variable topology and most owners love them.
OK thank you very much for those enlightments !
Not only the combination of acoustic/electrical Xo allows me to have 24dB filtering, but it also helps me fit the midrange driver in a three times smaller enclosure ! (36L instead of 100L)
Really great
But I am still afraid of this huge delay... Maybe I shouldn't care too much about it.
Not only the combination of acoustic/electrical Xo allows me to have 24dB filtering, but it also helps me fit the midrange driver in a three times smaller enclosure ! (36L instead of 100L)
Really great
But I am still afraid of this huge delay... Maybe I shouldn't care too much about it.
Are you sure that you got the numbers right? That sounds like a units error somewhere
Does your model allow reversing the connections on one of the drivers? What is the crossover frequency?
Linkwitz points out the importance of phase alignment - use his delay circuits to compensate. (Oh NO! more opamps!)
Does your model allow reversing the connections on one of the drivers? What is the crossover frequency?
Linkwitz points out the importance of phase alignment - use his delay circuits to compensate. (Oh NO! more opamps!)
No, I think there is no problem.
The fact is that I use a very big midrange driver vith a Qts of 0.56
In 125L, the Q of the enclosure is 0.707 and Fc is 76Hz
In 36L, the Q of the enclosure is 1 and Fc is 109Hz. I add the Q=0.5 Fc=109Hz filter and the overall Q becomes 0.5.
The little issue is that the modelled step response shows some overshoot that is not that strong in the bigger enclosure...
Lol more opamps ! I'll see first if I can add some delay through my soundcard at some frequencies, not sure though...
The fact is that I use a very big midrange driver vith a Qts of 0.56
In 125L, the Q of the enclosure is 0.707 and Fc is 76Hz
In 36L, the Q of the enclosure is 1 and Fc is 109Hz. I add the Q=0.5 Fc=109Hz filter and the overall Q becomes 0.5.
The little issue is that the modelled step response shows some overshoot that is not that strong in the bigger enclosure...
Lol more opamps ! I'll see first if I can add some delay through my soundcard at some frequencies, not sure though...
Hi,
Midrange driver going down to ~100Hz?
Most people would use a driver of 100mm to 170mm as a midrange and probably extend it down no lower than 200Hz to 300Hz. My 135mm driver (93mm cone) is -3db at 400Hz, although it is capable of going down to 69Hz, it would run out of Xmax too soon if it were used as an upper bass driver.
Midrange driver going down to ~100Hz?
Most people would use a driver of 100mm to 170mm as a midrange and probably extend it down no lower than 200Hz to 300Hz. My 135mm driver (93mm cone) is -3db at 400Hz, although it is capable of going down to 69Hz, it would run out of Xmax too soon if it were used as an upper bass driver.
AndrewT said:
In fact the driver is quite particular : it is sold as a fullrange driver but I wanna use it "extended range" in quite an high-end system.
It is the Supravox 215RTF and it is an 8" driver with Xmax=2mm
I have two choices to filter it :
- load it in a big volume with a low Fc and low Q, and filter it at 150Hz
- load it in the 35L box with both the filter and enclosure tuned at 109Hz.
In both cases, the speaker never runs out of Xmax at the rated power and still produces 114dB/1W/1m
It is filtered low to get all the bass qualities of this driver.
But the problem is that I get some problems in both cases :
- in the big volume, the filter is not "synchronized" with the natural rolloff of the enclosure and it may lead to phase/delay problems
- in the small enclosure, I get some ripple on the modelled step response which looks a bit like the step response of a bass reflex (what I precisely want to avoid)
I don't know which is the "least worse"...
(place is not my mian problem)Oops sorry...
Not 114dB/1W/1m, but 114dB/1m at full RMS power handling. Sensitivity is 97dB/1W/1w
I'm planning a 3-way : the boomer linkwitz transformed down to 20Hz, the Supravox from 160 to 4000 or 6000Hz, and a tweeter or supertweeter above.
I don't really need 4-way : my listening room is quite small (14m²) and as long as I know I have 110dB available from 30Hz to 20kHz, it's OK.
I'm modelling in FilterPro the combined effect of the enclosure rolloff and a different crossover point. It seems that I can end up with something virtually identical to an all-electric 4-pole filter. I need to check that, though.
Not 114dB/1W/1m, but 114dB/1m at full RMS power handling. Sensitivity is 97dB/1W/1w
I'm planning a 3-way : the boomer linkwitz transformed down to 20Hz, the Supravox from 160 to 4000 or 6000Hz, and a tweeter or supertweeter above.
I don't really need 4-way : my listening room is quite small (14m²) and as long as I know I have 110dB available from 30Hz to 20kHz, it's OK.
I'm modelling in FilterPro the combined effect of the enclosure rolloff and a different crossover point. It seems that I can end up with something virtually identical to an all-electric 4-pole filter. I need to check that, though.
I have chosen the Supravox driver for its exemplary behavior : this driver has one of the cleanest CSD I have ever seen, and has a very easily equalizable response.
Having a look here will convince you : http://www.supravox.fr/mesures/mes215RTF642.htm
That's why I want it to cover the widest possible range of frequencies : it has both much energy in the low-midrange and a very clean upper midrange. I get most of the music through this driver, and the extremes are covered by the 15" woofer and the tweeter.
I used to like the fullrange concept but now I really want to go serious
In fact, my aim for this project is to have the fullrange's resolving power and coherence with awesome dynamics and a full coverage of audible frequencies (20Hz-20000Hz)
Coming back to my filters, I have modelled the combined effect of a 126L enclosure with a 208Hz 12dB filter : I almost get the same response as a Q=0.5 Fc=160Hz 4-pole filter.
With the advantage of a much cleaner step response (no more ringing)
Having a look here will convince you : http://www.supravox.fr/mesures/mes215RTF642.htm
That's why I want it to cover the widest possible range of frequencies : it has both much energy in the low-midrange and a very clean upper midrange. I get most of the music through this driver, and the extremes are covered by the 15" woofer and the tweeter.
I used to like the fullrange concept but now I really want to go serious
In fact, my aim for this project is to have the fullrange's resolving power and coherence with awesome dynamics and a full coverage of audible frequencies (20Hz-20000Hz)
Coming back to my filters, I have modelled the combined effect of a 126L enclosure with a 208Hz 12dB filter : I almost get the same response as a Q=0.5 Fc=160Hz 4-pole filter.
With the advantage of a much cleaner step response (no more ringing)
Attachments
interesting concept
Hi,
interesting driver. As can be seen on the 60° freq-response the driver holds up its on-axis response above 2kHz by interference i.e narrowing distribution character. So a crossover at about 4kHz-6kHz could be problematic in sonical terms. I´d rather have a look if there´s any good tweeter to find that could work with the desired efficiency from app 2kHz on. Maybe some horn or the AMT (if money´s no object)
Have You thought of using the driver in (dampened) open baffle? Crossed over at app 200-300Hz could be a good solution, because You won´t have to worry about the high Qts of the driver anymore.
Since You use the driver as a midrange and so with a crossover-freq well above its Fs, the resultant Q-factor is not of much importance for the sonic quality. You can use small housings with resultant Q´s around 1 very well. Don´t use such a big volume for midrange! (keep in mind that TSP-values just help to design around the fs of a driver)
Having seen the parameters on the web I´d recommend using app 35-40L maximum and crossover point of 200Hz +, or an open baffle design (which would fit nicely to the AMT too).
With a 15" bass You will hardly get the SPL the midrange could reach, especially when using equalization. I ´d say build the system without the bass-eq first and just keep it as an option.
Have You taken the bass boost of Your room into account for example?
Calvin
Hi,
interesting driver. As can be seen on the 60° freq-response the driver holds up its on-axis response above 2kHz by interference i.e narrowing distribution character. So a crossover at about 4kHz-6kHz could be problematic in sonical terms. I´d rather have a look if there´s any good tweeter to find that could work with the desired efficiency from app 2kHz on. Maybe some horn or the AMT (if money´s no object)
Have You thought of using the driver in (dampened) open baffle? Crossed over at app 200-300Hz could be a good solution, because You won´t have to worry about the high Qts of the driver anymore.
Since You use the driver as a midrange and so with a crossover-freq well above its Fs, the resultant Q-factor is not of much importance for the sonic quality. You can use small housings with resultant Q´s around 1 very well. Don´t use such a big volume for midrange! (keep in mind that TSP-values just help to design around the fs of a driver)
Having seen the parameters on the web I´d recommend using app 35-40L maximum and crossover point of 200Hz +, or an open baffle design (which would fit nicely to the AMT too).
With a 15" bass You will hardly get the SPL the midrange could reach, especially when using equalization. I ´d say build the system without the bass-eq first and just keep it as an option.
Have You taken the bass boost of Your room into account for example?
Calvin
Many people seem to like open baffle for their "no box" aspect but I'm not totally sure it is the best compromise. Concerning place : assuming I want to use it down to 200Hz, I need a front panel width of 340/200/2 = 85cm !
I do have enough place to have big volume enclosures (I build up the volume by making tall enclosures), but I cannot have wide panels.
The big sealed box will almost behave like an open baffle, but closing the volume behind won't allow acoustical short circuit, hence allowing me to have a narrower front baffle. Its behavior is more predictable because there is no rear wave likely to ring on the walls behind. Off course, I'll design an enclosure with non-parallel walls to avoid the potential internal resonances.
As I said before, the small volume for the midrange + the effect of the active filter lead me to a form of ringing on the step response. I really want to avoid this because I know how it degrades the sound.
Furthermore, the group delay increases much more in the 35L enclosure than in the 126L one (in fact 100L, with damping it makes ~125L) and the same overall filter slope gives a less linear attenuation. (given is the step response of the 35L box crossed at 160Hz)
Concerning dispersion, I don't care much about 60° dispersion since most drivers are not able to give sound 60° off axis (even dome tweeters). At 30°, the response extends to 3-4 kHz which is enough for me. I don't want to cross lower, i.e in the most sensible bandwidth of human hearing.
When talking about tweeters, I was thinking of using either a standard dome tweeter (Seas 27TDFC or 27TBFCG) or a more "exotic" tweeter like the Fostex T90A horn or the AurumCantus G2Si ribbon. It will mainly depend on money in fact.
What kind of tweeter is AMT ? Horn, ribbon ?
The 15" bass driver will be the RCF L15P200AK or the Precision Devices PD1550. I think I'll go for the PD1550 but I'm not sure, though. Both can reach 400Hz with ease but I want a cutoff frequency of 160Hz to avoid using them above 200Hz (vertical room resonance at 210Hz where the 15" will be placed)
The LF gain of my room is not really obvious. According to calculations, I should expect some gain under 30Hz but it doesn't matter : I'll soon leave the place where I am living
Thanks for your advice !
I do have enough place to have big volume enclosures (I build up the volume by making tall enclosures), but I cannot have wide panels.
The big sealed box will almost behave like an open baffle, but closing the volume behind won't allow acoustical short circuit, hence allowing me to have a narrower front baffle. Its behavior is more predictable because there is no rear wave likely to ring on the walls behind. Off course, I'll design an enclosure with non-parallel walls to avoid the potential internal resonances.
As I said before, the small volume for the midrange + the effect of the active filter lead me to a form of ringing on the step response. I really want to avoid this because I know how it degrades the sound.
Furthermore, the group delay increases much more in the 35L enclosure than in the 126L one (in fact 100L, with damping it makes ~125L) and the same overall filter slope gives a less linear attenuation. (given is the step response of the 35L box crossed at 160Hz)
Concerning dispersion, I don't care much about 60° dispersion since most drivers are not able to give sound 60° off axis (even dome tweeters). At 30°, the response extends to 3-4 kHz which is enough for me. I don't want to cross lower, i.e in the most sensible bandwidth of human hearing.
When talking about tweeters, I was thinking of using either a standard dome tweeter (Seas 27TDFC or 27TBFCG) or a more "exotic" tweeter like the Fostex T90A horn or the AurumCantus G2Si ribbon. It will mainly depend on money in fact.
What kind of tweeter is AMT ? Horn, ribbon ?
The 15" bass driver will be the RCF L15P200AK or the Precision Devices PD1550. I think I'll go for the PD1550 but I'm not sure, though. Both can reach 400Hz with ease but I want a cutoff frequency of 160Hz to avoid using them above 200Hz (vertical room resonance at 210Hz where the 15" will be placed)
The LF gain of my room is not really obvious. According to calculations, I should expect some gain under 30Hz but it doesn't matter : I'll soon leave the place where I am living
Thanks for your advice !
Attachments
The frequency response of the 35L filtered enclosure : compare with the graph I posted yesterday, and note the higher group delay and less linear response.
The 100L enclosure isn't such a problem for me. It just has to be a bit tall and deep but 100L isn't really that big.
The woofer will take place in a ~65L box.
The 100L enclosure isn't such a problem for me. It just has to be a bit tall and deep but 100L isn't really that big.
The woofer will take place in a ~65L box.
Attachments
comments
Hi,
maybe I made some comments not clear enough, but You still seem to lay waight on points which don´t matter much.
You have to take the drivers TSP-parameters into account when using it down close to its Fs. But its good use and common practise to stay away at minimum one octave from Fs. Here the TSPs are of nearly no interest at all. So any simulations about the drivers behaviour around Fs (Step response!) are of no use when Your drivers passband begins more than an octave higher. Using the Supravox from lets say 200Hz-300Hz on the simulated step response doesn´t interest much at all as well as the group delay. You can happily design for a small box (ok ok, I wouldn´t recommend a Qt higher than app 1.2 )
Having heard of a 15" driver as bass I didn´t worry much about the width of the speakers front. Therefore open baffle came to my mind since it doesn´t need ´volume´ and You can play with the sound from the backside by adding damping material.
With a wider front You won´t have to compensate much for the acoustic cancellation. Even in a CB You will have to compensate for the baffle step if the front is small. A wider front preserves the good efficiency of the driver and lowers the baffle step. With a good 15" driver You could end up with ~ 95dB efficiency between 40Hz to 20kHz. With a smaller front You might end by just 90dB. To compensate for the baffle step You normally use a larger series inductance, but that might not work out when placing the crossover higher than 2kHz. So apart from lower sensitivity You might have to design a more complex crossover just because of a too small front
The AMT is a remarkable tweeter using a folded film diaphragm. The original big version works as a dipole and features a very smooth freq response from 2kHz on, very low distortion distortion levels and a high efficiency of ~100dB@2.83V/1m (~97dB@1W/1m). It can be stood just upon a normal box since it can´t be mounted like a normal Tweeter. But its a quite costly thing.
An alternative Tweeter could be one out of the HiVi Research RT2 series (available through PartsExpress). The RT2-Pro and RT2H-A and if efficiency is low enough RT2C-A. These are isodynamic ribbons You may use from ~3-4kHz on.
Most real ribbons show high distortion below 5kHz, so I´d test a ribbon like the Aurum before or at least try to get independent information.
The dispersion curves are of interest, because a steep change in distribution character between the drivers is audible. If You use a midrange driver with narrow distribution a tweeter with equally narrow distribution at its lower freq range is advantageous. Horns or Waveguides come to my mind then, but not necessarily real thin ribbons.
Tweeters like the SEASs will be inappropriate when using 15" drivers with high efficiency. The Focal 120 could have been
a good partner instead.
jauu
Calvin
Hi,
maybe I made some comments not clear enough, but You still seem to lay waight on points which don´t matter much.
You have to take the drivers TSP-parameters into account when using it down close to its Fs. But its good use and common practise to stay away at minimum one octave from Fs. Here the TSPs are of nearly no interest at all. So any simulations about the drivers behaviour around Fs (Step response!) are of no use when Your drivers passband begins more than an octave higher. Using the Supravox from lets say 200Hz-300Hz on the simulated step response doesn´t interest much at all as well as the group delay. You can happily design for a small box (ok ok, I wouldn´t recommend a Qt higher than app 1.2
)Having heard of a 15" driver as bass I didn´t worry much about the width of the speakers front. Therefore open baffle came to my mind since it doesn´t need ´volume´ and You can play with the sound from the backside by adding damping material.
With a wider front You won´t have to compensate much for the acoustic cancellation. Even in a CB You will have to compensate for the baffle step if the front is small. A wider front preserves the good efficiency of the driver and lowers the baffle step. With a good 15" driver You could end up with ~ 95dB efficiency between 40Hz to 20kHz. With a smaller front You might end by just 90dB. To compensate for the baffle step You normally use a larger series inductance, but that might not work out when placing the crossover higher than 2kHz. So apart from lower sensitivity You might have to design a more complex crossover just because of a too small front
The AMT is a remarkable tweeter using a folded film diaphragm. The original big version works as a dipole and features a very smooth freq response from 2kHz on, very low distortion distortion levels and a high efficiency of ~100dB@2.83V/1m (~97dB@1W/1m). It can be stood just upon a normal box since it can´t be mounted like a normal Tweeter. But its a quite costly thing.
An alternative Tweeter could be one out of the HiVi Research RT2 series (available through PartsExpress). The RT2-Pro and RT2H-A and if efficiency is low enough RT2C-A. These are isodynamic ribbons You may use from ~3-4kHz on.
Most real ribbons show high distortion below 5kHz, so I´d test a ribbon like the Aurum before or at least try to get independent information.
The dispersion curves are of interest, because a steep change in distribution character between the drivers is audible. If You use a midrange driver with narrow distribution a tweeter with equally narrow distribution at its lower freq range is advantageous. Horns or Waveguides come to my mind then, but not necessarily real thin ribbons.
Tweeters like the SEASs will be inappropriate when using 15" drivers with high efficiency. The Focal 120 could have been
a good partner instead.
jauu
Calvin
Hi,
If your philosophy is to avoid a crossover below that, then you need a speaker that extends about an octave above what you are proposing. That's why I was surprised when you said 8inch mid driver.
Cheap two ways used 8inch and 1inch for a long time but even they have gone out of fashion, only a few (maybe none) could be called high quality.
normally this would require a crossover about 1 octave below the smoothish limit of the speaker.
If your philosophy is to avoid a crossover below that, then you need a speaker that extends about an octave above what you are proposing. That's why I was surprised when you said 8inch mid driver.
Cheap two ways used 8inch and 1inch for a long time but even they have gone out of fashion, only a few (maybe none) could be called high quality.
Re: comments
This is extremely important. Read through the white papers at Harman Intl.'s website. I don't remember which paper, but with a large number of educated subjects (not just Joe Ipod, but people who understood audio quality) in a blind test Harman found almost universally that speakers with smoothly changing dispersion patterns were preferred. This preference was strong, even when comparing smooth dispersion pattern speakers with fairly ragged frequency response to speakers with ruler flat on axis response but rapidly changing polar response with frequency.
Without a waveguide/horn to control the tweeter directivity you'll have a large discontinuity in the power response at the crossover to the tweeter.
If you are shooting for more than a mediocre-average result, consider crossing the tweeter in much lower unless you use a waveguide. I'd aim for 1500 or lower, and give up some of the efficiency target. You could triamp the system and not worry about tweeter sensitivity for reasonable listening levels. Try the Seas Millenium at 1 kHz with a cauer filter around 8th order initial roll off.
Notice the wrinkles in the mid's impedance curve at 1kHz and 2 kHz? They most likely indicate a cone edge resonance, another reason to cross this driver low. It would be interesting to see distortion data on it.
Sorry if my bias against "full range" drivers shows too blatantly.
Calvin said:
This is extremely important. Read through the white papers at Harman Intl.'s website. I don't remember which paper, but with a large number of educated subjects (not just Joe Ipod, but people who understood audio quality) in a blind test Harman found almost universally that speakers with smoothly changing dispersion patterns were preferred. This preference was strong, even when comparing smooth dispersion pattern speakers with fairly ragged frequency response to speakers with ruler flat on axis response but rapidly changing polar response with frequency.
Without a waveguide/horn to control the tweeter directivity you'll have a large discontinuity in the power response at the crossover to the tweeter.
If you are shooting for more than a mediocre-average result, consider crossing the tweeter in much lower unless you use a waveguide. I'd aim for 1500 or lower, and give up some of the efficiency target. You could triamp the system and not worry about tweeter sensitivity for reasonable listening levels. Try the Seas Millenium at 1 kHz with a cauer filter around 8th order initial roll off.
Notice the wrinkles in the mid's impedance curve at 1kHz and 2 kHz? They most likely indicate a cone edge resonance, another reason to cross this driver low. It would be interesting to see distortion data on it.
Sorry if my bias against "full range" drivers shows too blatantly.
Calvin :
you open baffle idea sounds quite nice : if I damp the rear of the baffle, only the bass/lowmid will reflect on the walls behind and compensate for BSC. Using a U-shaped open baffle would allow me to reduce the front baffle width.
A solution I will consider, for sure.
BTW efficiency is not a problem for me : I have six 300W amps for the woofers, six 300W amps for the midrange, and eight 100W amps for the tweeters These are studio amps a very nice neighbor donated me. Just have to repair some of them and add the PSU
The AMT tweeters look like a piece of art but are really too expensive for me.
Why that if I use active filtering ? Maybe a power handling problem ?
AndrewT and BobEllis : you really convinced me to adopt a lower crossover point. In my case, I guess a ribbon tweeter wouldn't be the best match as these units have very wide dispersion.
Do you think the Seas 27TDFC could do the trick ? it is less expensive than the the Millenium and seems to behave as well (according to www.zaphaudio.com )
The waveguide sounds also like a good idea. I will see if my carpenter friend could build this for me.
you open baffle idea sounds quite nice : if I damp the rear of the baffle, only the bass/lowmid will reflect on the walls behind and compensate for BSC. Using a U-shaped open baffle would allow me to reduce the front baffle width.
A solution I will consider, for sure.
BTW efficiency is not a problem for me : I have six 300W amps for the woofers, six 300W amps for the midrange, and eight 100W amps for the tweeters
These are studio amps a very nice neighbor donated me. Just have to repair some of them and add the PSU The AMT tweeters look like a piece of art but are really too expensive for me.
Why that if I use active filtering ? Maybe a power handling problem ?
AndrewT and BobEllis : you really convinced me to adopt a lower crossover point. In my case, I guess a ribbon tweeter wouldn't be the best match as these units have very wide dispersion.
Do you think the Seas 27TDFC could do the trick ? it is less expensive than the the Millenium and seems to behave as well (according to www.zaphaudio.com )
The waveguide sounds also like a good idea. I will see if my carpenter friend could build this for me.
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