@PKAudio
I traced the FRD from Span-speak's datasheet and imported into REW. It looks like there was a problem with my tracing in VituixCAD that shifted the resonance from 500 hz to 1300 hz. Thanks for pointing me to the hificompass link which made review the datasheet again. My question was essentially is this woofer worth the price?
Edit
I retraced the data and I had no trouble crossing the two drivers at 400 hz. I had the set low range marker at 20hz, but the typed value was set at 100hz. This shifted both drivers over two octaves higher, no wonder I failed.
I traced the FRD from Span-speak's datasheet and imported into REW. It looks like there was a problem with my tracing in VituixCAD that shifted the resonance from 500 hz to 1300 hz. Thanks for pointing me to the hificompass link which made review the datasheet again. My question was essentially is this woofer worth the price?
Edit
I retraced the data and I had no trouble crossing the two drivers at 400 hz. I had the set low range marker at 20hz, but the typed value was set at 100hz. This shifted both drivers over two octaves higher, no wonder I failed.
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The Monacor SPH250KE can be cross over 500hz, like I have already done.
So as suggest by @flex2 I think to choose again the SPH250KE with the future project.
At this point there is no compromise to choose the midrange (apart the cost)
So Let's say I would like to allocate a budget between 170-300 Euro for the midrange.
Actually I would be inclined to consider one of these 4:
1) Morel EM 1308
2) TANG BAND 75-1558SH
3) Scan-speak 12MU-8731T00
4) Satori MR13TX-4
to use with SPH250KE, but I'm undecided which one to choose
So as suggest by @flex2 I think to choose again the SPH250KE with the future project.
At this point there is no compromise to choose the midrange (apart the cost)
So Let's say I would like to allocate a budget between 170-300 Euro for the midrange.
Actually I would be inclined to consider one of these 4:
1) Morel EM 1308
2) TANG BAND 75-1558SH
3) Scan-speak 12MU-8731T00
4) Satori MR13TX-4
to use with SPH250KE, but I'm undecided which one to choose
In the 3-way systems I have built, it was always a struggle to really align the phase of the woofer-to-midrange crossover point. For that reason, I was always happiest with builds that incorporated a full-range driver as the midrange. Then the 'presence' of voices and instruments is improved by pushing the crossover points higher for the tweeter and lower for the woofer. Even the best of drivers will not sound good without a really well designed crossover, and I was never very good at it! Compared to the three midrange choices above, I would always much prefer a driver like the MarkAudio MAOP 11, or MAOP 10. They would give you the option of moving the crossover point down, if it sounds better. [Also, elsewhere on DIYAudio, users have complained about the Scan-speak 12MU-8731T00 breaking up with challenging voices.]
Edit: Among the four you more recently listed, I would choose the Satori MR13TX-4. The carbon fiber cone is good, and you would just have to keep the tweeter crossover point below the frequency where the cone begins to break-up. ...maybe about 4k with 18dB/octave or steeper?
.
MarkAudio MAOP 11
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I would say that all 2" or 3" dome midranges are waste of time.
If Fs (self resonanse) is around 300 Hz, which they are, you need to start your high pass filter 2 octaves higher which is at 1,2 kHz and you do not want your 10" bass driver to cover all of the midrange in a 74 liter box. That will be very coloured and bad sounding.
So easily ScanSpeak 12MU, but that also have quite high self resonance which pushes the high pass filter to around 600 Hz.
I would suggest a cross over point of around 400Hz and a cabinet volume of midrange around 5 liters.
To be able to use a cross over point of 400 Hz you need the midrange driver to have a self resonance point below 100 Hz.
Preferably even lower than that. Close to 50-70 Hz would be good.
Breakup of midrange is very much depending on the voice coil diameter.
2" and 3" will break up earlier than a 1" voicecoil.
That's also against the dome midranges. These dome will never make you happy.
I tried to use them once and awhile in my early days of designing loudspeakers but gave up. They are not good and have severe limitations.
Keep voice coil at 25 or 30 mm to be able to reach 2,5-3,0 kHz cross over region without significant breakups.
Select midrange driver with breakup at least an octave above cross over point. So aim for linear response to 5 kHz and as linear roll uff as possible until 10kHz.
So there is a great task to find a midrange driver that can handle that.
Look among 5" and 4" drivers.
Personally I would go for a 5" midwoofer or midrange driver and a cabinet volume of around 5 liter to get the best mix to match both bass and tweeter.
Even if 12MU is extremely good it probably is too small to mate well with a 10" bass driver.
It needs to be mated with a 6,5 to 7" driver like Wilson audio do in their better loudspeakers like Chronosonic XVX or WAMM Master Chronosonic.
A copper cap on the pole piece if prefered for the midrange so selecta that is possible.
I will make some suggestions later in the evening...
Thank you @flex2 ,
I the meantime I have checked these mid-woofers:
//
Seas Excel W15CY001 -> 5.5" (340 Euro)
Satori MW13TX-8 ------> 5" (274 Euro)
Seas Excel W12CY003 -> 4.5" (239 Euro)
Satori MR13P-8 --------> 5" (180 Euro)
//
for your opinion there is someone that can be match with SPH250KE ?
I the meantime I have checked these mid-woofers:
//
Seas Excel W15CY001 -> 5.5" (340 Euro)
Satori MW13TX-8 ------> 5" (274 Euro)
Seas Excel W12CY003 -> 4.5" (239 Euro)
Satori MR13P-8 --------> 5" (180 Euro)
//
for your opinion there is someone that can be match with SPH250KE ?
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Hi,
so is the Morel Supreme ST 1048 so bad compared to the others?
I would just like an opinion on why it wasn't even taken into consideration.
so is the Morel Supreme ST 1048 so bad compared to the others?
I would just like an opinion on why it wasn't even taken into consideration.
My impression is that BlieSMa T34A-4 is better then Morel Supreme ST 1048 .
I have just read many reviews where they speak well of it.
At the moment I would be intent on evaluating this.
The model T34B-4 cost 100 more (400 Euro) that is over my budget.
So I think the T34A-4 is good choice.
I have just read many reviews where they speak well of it.
At the moment I would be intent on evaluating this.
The model T34B-4 cost 100 more (400 Euro) that is over my budget.
So I think the T34A-4 is good choice.
Midrange recommendations:
Your selection:
//
Seas Excel W15CY001 -> 5.5" (340 Euro), Problematic frequency response and 3rd order distortion prominent over 2nd. Will not sound as good as others.
https://hificompass.com/en/speakers/measurements/seas/seas-w15cy001-e0015
Satori MW13TX-8 ------> 5" (274 Euro), Excellent choice. Read more comments below.
https://hificompass.com/en/speakers/measurements/satori/satori-mw13tx-8
Seas Excel W12CY003 -> 4.5" (239 Euro), Don't like this one. 3% distortion peak at 1kHz will sound coloured. Too many dips and peaks.
https://hificompass.com/en/speakers/measurements/seas/seas-w12cy003-e0044
Satori MR13P-8 --------> 5" (180 Euro), Unnecessary dip at 1,5 kHz. There are better choices. Too much energy in the breakup region.
https://hificompass.com/en/speakers/measurements/satori/satori-mr13p-8
//
Would like to suggest some more in some different groupings.
Group 1, cost no object.
SB Acoustics Satori MW13TX-8 https://hificompass.com/en/speakers/measurements/satori/satori-mw13tx-8
SB Acoustics SB13NBAC30-8 https://www.dibirama.it/home-page/m...sb15nbac30-8-mid-woofer-5-8-ohm-100-wmax.html
ScanSpeak 15W/8530K00 https://www.dibirama.it/home-page/m...-15w-8530k00-mid-woofer-5-8-ohm-110-wmax.html
Group 2. A step behind group 1 in performance but still very very good.
Peerless HDS-P830991 Glassfiber cone. https://www.dibirama.it/home-page/mid-woofer/314-peerless-hds-p830991-mid-w-5-8-ohm-60wmax.html
Peerless HDS-P830860 Polypropylene cone
Peerless HDS-P832873 Nomex paper cone
ScanSpeak Discovery 15W/8434G00 https://www.dibirama.it/home-page/m...-15w-8434g00-mid-woofer-5-8-ohm-120-wmax.html
Look at distortion.
Should be low (below 0,5% at least for 1 W) and linear.
The less dips and peaks in frequency response the better. A peak of 1 dB over an octave can be detected. A peak of 2dB over an octave I would say is a colouration and unwanted in a high end design.
The more linear impedance curve of the higher registers the better.
Like the HDS drivers from Peerless a lot but think you want to take a step further and then a driver from Group 1 would be the best choice.
HDS drivers I had at home at the moment...
Your selection:
//
Seas Excel W15CY001 -> 5.5" (340 Euro), Problematic frequency response and 3rd order distortion prominent over 2nd. Will not sound as good as others.
https://hificompass.com/en/speakers/measurements/seas/seas-w15cy001-e0015
Satori MW13TX-8 ------> 5" (274 Euro), Excellent choice. Read more comments below.
https://hificompass.com/en/speakers/measurements/satori/satori-mw13tx-8
Seas Excel W12CY003 -> 4.5" (239 Euro), Don't like this one. 3% distortion peak at 1kHz will sound coloured. Too many dips and peaks.
https://hificompass.com/en/speakers/measurements/seas/seas-w12cy003-e0044
Satori MR13P-8 --------> 5" (180 Euro), Unnecessary dip at 1,5 kHz. There are better choices. Too much energy in the breakup region.
https://hificompass.com/en/speakers/measurements/satori/satori-mr13p-8
//
Would like to suggest some more in some different groupings.
Group 1, cost no object.
SB Acoustics Satori MW13TX-8 https://hificompass.com/en/speakers/measurements/satori/satori-mw13tx-8
Very low distortion below 0,1% in the working area and very good linearity between 2nd and 3rd harmonic will give a very neutral, open and clean sound without any disturbing regions. One of the best drivers at the moment, but at a price of course. High rolloff fairly easy to handle. Copper cap 🙂
SB Acoustics SB13NBAC30-8 https://www.dibirama.it/home-page/m...sb15nbac30-8-mid-woofer-5-8-ohm-100-wmax.html
Almost as good as Satori MW13TX-8 but with a severe break up peak, but surprizingly without the distortion peak that normally result from breakup.
Excellent driver with good linearity and very low and even distortion. Copper sleve on pole piece for top sound.
Will probably need a notch filter to lower the break up peak. 🙂
ScanSpeak 15W/8530K00 https://www.dibirama.it/home-page/m...-15w-8530k00-mid-woofer-5-8-ohm-110-wmax.html
Very smooth frequency response and linear and low distortion. Smooth rolloff will make cross over design a walk in the park.
Paper cone will be a bit softer on your ear compared to the harder cones above. Will work very well in this design. Copper cap on pole piece. 🙂
Group 2. A step behind group 1 in performance but still very very good.
Peerless HDS-P830991 Glassfiber cone. https://www.dibirama.it/home-page/mid-woofer/314-peerless-hds-p830991-mid-w-5-8-ohm-60wmax.html
Peerless HDS-P830860 Polypropylene cone
Peerless HDS-P832873 Nomex paper cone
HDS 5,25" drivers is almost as good as it gets regardless of price. I have used these drivers a lot and them perform very well and are easy to work with.
No detectable colouration and very low distortion overall. As linear as a straight line. Would easily make it to Group 1 if they had a copper capped pole piece. Might would have selected this series of drivers my self for this design. That's how good they are. Love them...
A dB higher sensitivity than Group 1 could be reason enough to make this your first choice.
Out of these three I would select the Nomex paper cone first since glass fiber cone a bit soft and polypropylene changes more with temperature
which slightly will effect performance on hot summer days.
Dayton Audio DSA135-8 https://www.dibirama.it/home-page/m...dio-dsa135-8-mid-woofer-5-8-ohm-100-wmax.htmlHave not tried this one, but data looks as promising as SB13NBAC30-8 but with a rolloff that is easier to handle. With more copper on the pole piece it might rival SB13NBAC30-8.
ScanSpeak Discovery 15W/8434G00 https://www.dibirama.it/home-page/m...-15w-8434g00-mid-woofer-5-8-ohm-120-wmax.html
Have not used this one, but it seems very similar to Peerless HDS-P830991 which I like a lot.
Little better sensitivity on this one is welcome. Need to buy this soon to learn more.
I think any of the above drivers are good enough to be in your design.Look at distortion.
Should be low (below 0,5% at least for 1 W) and linear.
The less dips and peaks in frequency response the better. A peak of 1 dB over an octave can be detected. A peak of 2dB over an octave I would say is a colouration and unwanted in a high end design.
The more linear impedance curve of the higher registers the better.
Like the HDS drivers from Peerless a lot but think you want to take a step further and then a driver from Group 1 would be the best choice.
HDS drivers I had at home at the moment...
The Morel Supreme tweeters are very nice. If I had the choice though, i would not choose the largest faceplates to yield more placement options. The ST 728, 1048, 1108, or 1308 are all the same tweeter with different faceplates. I have always wanted to use the 728, but have not yet had the opportunity.
However, the TSCT Supreme tweeters are copper sleeved, and reportedly one of the lowest HD tweeters on the market.
Neither a bad choice.
However, the TSCT Supreme tweeters are copper sleeved, and reportedly one of the lowest HD tweeters on the market.
Neither a bad choice.
Many Many thanks for detailed information !!!
What you think of this combination:
Woofer: Monacor SPH250KE
crossover cut: 400 Hz
Midrange: SB Acoustics Satori MW13TX-8
crossover cut: 2 Khz
Tweeter: BlieSMa T34A-4
The BlieSMa T34A-4 should be better the my Visaton KE 25SC
For midrange a closed volume box of 5 liters.
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marcop999 wrote:
"""""""""""""""""""""""""""""""""""""""""""""""""
What you think of this combination:
Woofer: Monacor SPH250KE
crossover cut: 400 Hz
Midrange: SB Acoustics Satori MW13TX-8
crossover cut: 2 Khz
Tweeter: BlieSMa T34A-4
"""""""""""""""""""""""""""""""""""""""""""""""""
Yes, I see only very good selection of drivers here.
One of my personal favourites of tweeter is Seas 27TBFC/G and BlieSMa T34A-4 have equal or better performance so I think it is a very good tweeter indeed.
Resonant peak is a bit high though which indicates that there are a risk of some colouration from the rear chamber around the resonant peak, so make sure you have a notch filter to surpress the rising impedance created by resonant peak.
That will help the high pass filter of the tweeter to surpress any colourations as low as possible and give you a better chance to get that very linear impedance in the end.
Next important question is about configuration of frequency response.
Have you learned about baffle step compensation and plan to adopt it or do you aim at the straightest possible frequency response?
What kind of measurement system do you have?
Look here...
Troels already designed suitable notch filter to surpress impedance peak. Less work for you...
http://www.troelsgravesen.dk/BlieSMa_T34A-4.htm
"""""""""""""""""""""""""""""""""""""""""""""""""
What you think of this combination:
Woofer: Monacor SPH250KE
crossover cut: 400 Hz
Midrange: SB Acoustics Satori MW13TX-8
crossover cut: 2 Khz
Tweeter: BlieSMa T34A-4
"""""""""""""""""""""""""""""""""""""""""""""""""
Yes, I see only very good selection of drivers here.
One of my personal favourites of tweeter is Seas 27TBFC/G and BlieSMa T34A-4 have equal or better performance so I think it is a very good tweeter indeed.
Resonant peak is a bit high though which indicates that there are a risk of some colouration from the rear chamber around the resonant peak, so make sure you have a notch filter to surpress the rising impedance created by resonant peak.
That will help the high pass filter of the tweeter to surpress any colourations as low as possible and give you a better chance to get that very linear impedance in the end.
Next important question is about configuration of frequency response.
Have you learned about baffle step compensation and plan to adopt it or do you aim at the straightest possible frequency response?
What kind of measurement system do you have?
Look here...
Troels already designed suitable notch filter to surpress impedance peak. Less work for you...
http://www.troelsgravesen.dk/BlieSMa_T34A-4.htm
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For measure I have a calibrated Beyerdynamic mic mm1, hope will be sufficient.
About baffle step compensation I known the base concept, but I don't kwown exactly how calculate it.
About the impedence I think is a good idea add a LRC circuit to tweeter, my actual Visaton KE 25SC have it built it inside.
Please correct me if I wrong:
If I cut the woofer at 400Hz, the distance between woofer and midrange is irrelevant. In theory I could also place at 50cm away ? I have seen that in that range the off-axis deviation is negligible. Do you confirm ?
About baffle step compensation I known the base concept, but I don't kwown exactly how calculate it.
About the impedence I think is a good idea add a LRC circuit to tweeter, my actual Visaton KE 25SC have it built it inside.
Please correct me if I wrong:
If I cut the woofer at 400Hz, the distance between woofer and midrange is irrelevant. In theory I could also place at 50cm away ? I have seen that in that range the off-axis deviation is negligible. Do you confirm ?
Beyerdynamic mm1 and REW for software ?
Usually I would say that centre to centre of drivers should be placed half the distance of the wave length of the cross over point.
In your case 400Hz/2x340m/s = 0,425 m, but you can extend that to full wave length without significant problem.
So up to 85 cm between bass and midrange, but better if closer to 45 cm centre to centre.
You will be more plagued by first floor reflection which will cause a significant dip in amplitude because out of phase sound wave.
Normally this occurs in the 80-200 Hz region depending on bass drivers distance to floor.
Longer distance will create a wider and deeper dip while smaller distance will create a narrower and more shallow dip.
So placing the bass driver closer to floor will help to keep the frequency response as linear as possible.
So place the driver low.
If you remember I recommended two driver placed with different distances to the floor which will help to further linearize frequency response.
Now you wanted one bass driver so you need to do what you can to eliminate the problem.
A 45 degree sloping baffle between bass driver and floor will also help a lot to reduce the dip.
Not pretty, but effective.
Usually I would say that centre to centre of drivers should be placed half the distance of the wave length of the cross over point.
In your case 400Hz/2x340m/s = 0,425 m, but you can extend that to full wave length without significant problem.
So up to 85 cm between bass and midrange, but better if closer to 45 cm centre to centre.
You will be more plagued by first floor reflection which will cause a significant dip in amplitude because out of phase sound wave.
Normally this occurs in the 80-200 Hz region depending on bass drivers distance to floor.
Longer distance will create a wider and deeper dip while smaller distance will create a narrower and more shallow dip.
So placing the bass driver closer to floor will help to keep the frequency response as linear as possible.
So place the driver low.
If you remember I recommended two driver placed with different distances to the floor which will help to further linearize frequency response.
Now you wanted one bass driver so you need to do what you can to eliminate the problem.
A 45 degree sloping baffle between bass driver and floor will also help a lot to reduce the dip.
Not pretty, but effective.
Thank you, that is what I have in mind.
Another idea (but I don't known yet if can be useful) is add a separator (without holes apart the one for wires) a few cm below the midange to divide the woofer and midrange chambers.
I' don't yet calculate exactly the point but I guess if I did something like that the medium's chamber could be quite voluminous probably greater than 5 liters.
If I cut to 400 Hz, for your opinion what is the maximum volume for midrange chamber without risk to alter too much the frequency response ?
Another solution will be create an embedded chamber only for mirange but I don't known if it is the best choice.
Another idea (but I don't known yet if can be useful) is add a separator (without holes apart the one for wires) a few cm below the midange to divide the woofer and midrange chambers.
I' don't yet calculate exactly the point but I guess if I did something like that the medium's chamber could be quite voluminous probably greater than 5 liters.
If I cut to 400 Hz, for your opinion what is the maximum volume for midrange chamber without risk to alter too much the frequency response ?
Another solution will be create an embedded chamber only for mirange but I don't known if it is the best choice.
A word about the baffle step compensation.
By theory bass spread sound in full space (360°) space while upper midrange and treble spread in half space (180°).
So you the energy from the speaker need to fill a bigger volume in bass compared to the higher registers.
In theory bass needs twice the energy.
The transition is gradual according to the yellow curve, and width of baffle defines where the transition starts.
Rounding and chamfering of edges have an influence too, and it's good practice to keep the baffle as narrow as possible or round edges quite much.
https://heissmann-acoustics.de/en/kantendiffraktion-sekundaerschallquellen-treiberanordnun/
To compensate for this bass theoretically needs to be 6dB higher in frequency reponse than higher registers.
In practice only a part of it needs to be compensated for and it also depends on room size and how close to walls the speaker should be placed.
I think 3-4 dB higher level of the bass driver compared to midrange driver is good enough since reverb from the room also will add some energy.
Technically it can be solved in several ways, but in your case I think the easiest is to lower the low pass filter point of bass driver to approx. 200 Hz instead of 400 Hz, and let the midrange have it's high pass filter point at 400Hz.
I think you can start with a a standard 2nd order cross over for bass driver at 400 Hz and the increase the inductor gradually until you get the target you set.
Depends on the type of filter you would like to use, but I would not look at anything else than 2nd order cross overs for this design.
Below 50 Hz room gain kicks in as a consequence the bass output needs to roll off.
Pink curve is an example of suitable taget curve for near field measurement.
Hit that one and you will get a fairly straight frequency response in your room.
By theory bass spread sound in full space (360°) space while upper midrange and treble spread in half space (180°).
So you the energy from the speaker need to fill a bigger volume in bass compared to the higher registers.
In theory bass needs twice the energy.
The transition is gradual according to the yellow curve, and width of baffle defines where the transition starts.
Rounding and chamfering of edges have an influence too, and it's good practice to keep the baffle as narrow as possible or round edges quite much.
https://heissmann-acoustics.de/en/kantendiffraktion-sekundaerschallquellen-treiberanordnun/
To compensate for this bass theoretically needs to be 6dB higher in frequency reponse than higher registers.
In practice only a part of it needs to be compensated for and it also depends on room size and how close to walls the speaker should be placed.
I think 3-4 dB higher level of the bass driver compared to midrange driver is good enough since reverb from the room also will add some energy.
Technically it can be solved in several ways, but in your case I think the easiest is to lower the low pass filter point of bass driver to approx. 200 Hz instead of 400 Hz, and let the midrange have it's high pass filter point at 400Hz.
I think you can start with a a standard 2nd order cross over for bass driver at 400 Hz and the increase the inductor gradually until you get the target you set.
Depends on the type of filter you would like to use, but I would not look at anything else than 2nd order cross overs for this design.
Below 50 Hz room gain kicks in as a consequence the bass output needs to roll off.
Pink curve is an example of suitable taget curve for near field measurement.
Hit that one and you will get a fairly straight frequency response in your room.
The volume of the midrange chamber has very little to do with the frequency response.
The size is important for resonanse control and standing waves inside the cabinet.
A big volume is bad at supporting the midrange driver and that will sound bad.
Different registers needs different volumes to perform their best and if you look at for example Wilson Audio WAMM Master Chronosonic they devide
volumes to four different volumes according to driver size and needs.
5 liter is a good volume for midrange up too around 2kHz.
Different sizes of cabinets have different tone where they sound the best.
Compare it with instruments like cello and violin.
Same technology, different frequency area of optimized sound.
So please keep the 5 liter size regardless of design. Wall thickness around 30 mm for midrange and put ~25-30 mm of rockwool insulation or other dampening material on all walls inside.
The size is important for resonanse control and standing waves inside the cabinet.
A big volume is bad at supporting the midrange driver and that will sound bad.
Different registers needs different volumes to perform their best and if you look at for example Wilson Audio WAMM Master Chronosonic they devide
volumes to four different volumes according to driver size and needs.
5 liter is a good volume for midrange up too around 2kHz.
Different sizes of cabinets have different tone where they sound the best.
Compare it with instruments like cello and violin.
Same technology, different frequency area of optimized sound.
So please keep the 5 liter size regardless of design. Wall thickness around 30 mm for midrange and put ~25-30 mm of rockwool insulation or other dampening material on all walls inside.
Thank you for this suggestion, and to explain me the step compensation, but to be honest I have never seen a project with with such a large frequency “hole” of 200Hz between woofer and midrange.
Do you have some example of crossover like this ?
In terms of cost this make a difference becouse I use always air inductors with small RDC.
Cut woofers at 200 Hz need a very high value of inductors and capacitors.
However if this make difference I will do.
However normally when I do a measuration I measure the single speaker at only 3/4 cm.
I use REW.
Measure the entire speaker is not easy becouse environmental factors such as outside noise or wooden furniture, glass, all things that would affect the measurement and are not dependent on the speaker itself also come into play.
Do you have some example of crossover like this ?
In terms of cost this make a difference becouse I use always air inductors with small RDC.
Cut woofers at 200 Hz need a very high value of inductors and capacitors.
However if this make difference I will do.
However normally when I do a measuration I measure the single speaker at only 3/4 cm.
I use REW.
Measure the entire speaker is not easy becouse environmental factors such as outside noise or wooden furniture, glass, all things that would affect the measurement and are not dependent on the speaker itself also come into play.
It will not result in a "hole", but a gradually sloping midrange and the goal is to have a 3-4 dB slope between 150-650 Hz a little bit depending on the baffle width you select for this project.
KEF are really good at designing for great performance inside the room.
Look at figure 4 where you can see the gradual slope and the necessary roll off in low bass.
This type of frequency response will be very linear when placed inside a room.
https://www.stereophile.com/content/kef-blade-two-meta-loudspeaker-measurements
https://www.stereophile.com/content/peak-consult-el-diablo-loudspeaker-measurements figure 3
Nice impedance curve too 🙂
KEF are really good at designing for great performance inside the room.
Look at figure 4 where you can see the gradual slope and the necessary roll off in low bass.
This type of frequency response will be very linear when placed inside a room.
https://www.stereophile.com/content/kef-blade-two-meta-loudspeaker-measurements
https://www.stereophile.com/content/peak-consult-el-diablo-loudspeaker-measurements figure 3
Nice impedance curve too 🙂
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Yes, this is exacly what you have write.
Hower I have looked the speakers you have post:
https://www.stereophile.com/floorloudspeakers/507peak/index.html
https://www.stereophile.com/content/kef-blade-two-meta-loudspeaker
in both case there is a uncommon placement on drivers, one put the tweeter and midrange diagonally and this can cause baffle step issue and is clear why need a compansation on crossover.
The other one have woofers on the side and also is clear why need a compansation.
However these project don't seem to have somephing in common with my apart the fact perhaps that the woofer is not quite on axis with respect to the other drivers becouse is not close to midrange.
About the impedence I don't think is easy get a flat line with a so large crossover gap. I don't understand how they did it
Suppose for example that the woofer is close to midrange at only 3/4 cm, for your opinion need a baffle step compesation ?
Hower I have looked the speakers you have post:
https://www.stereophile.com/floorloudspeakers/507peak/index.html
https://www.stereophile.com/content/kef-blade-two-meta-loudspeaker
in both case there is a uncommon placement on drivers, one put the tweeter and midrange diagonally and this can cause baffle step issue and is clear why need a compansation on crossover.
The other one have woofers on the side and also is clear why need a compansation.
However these project don't seem to have somephing in common with my apart the fact perhaps that the woofer is not quite on axis with respect to the other drivers becouse is not close to midrange.
About the impedence I don't think is easy get a flat line with a so large crossover gap. I don't understand how they did it
Suppose for example that the woofer is close to midrange at only 3/4 cm, for your opinion need a baffle step compesation ?
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It's easy to have a flat impedance curve. Just place complementing notch filters in parallell to the normal filter.
But you should only do it if you have a very weak amplifier that need a really flat impedance.
Parallell notch filter are only dummy loads that will not effect phase respons of the driver or cross over themself.
The are not a part of the loudspeaker design. Only parallell loads to make the amplifier feel better.
But you should only do it if you have a very weak amplifier that need a really flat impedance.
Parallell notch filter are only dummy loads that will not effect phase respons of the driver or cross over themself.
The are not a part of the loudspeaker design. Only parallell loads to make the amplifier feel better.