Nop ... Here in Montreal the majors are Bombardier (witch became Airbus recently) and Bell Helicopter, the aircraft machine shop business is quite strong in Quebec, I had chance to build military parts for McDonnell Douglas etc...
ok, so you eventually know things are more complex than you believe to know when not rulling a technology ?
I think people here try to help you in order that the plane can fly without crashing... 🙂 ... while you're still on the pilot seat !
I think people here try to help you in order that the plane can fly without crashing... 🙂 ... while you're still on the pilot seat !
A 10" driver becomes directive and gets thin before it reaches 2kHz. This could be explaining your apparent lack of midrange. All 10" drivers do this at near the same frequency. You need to fill in the 2-5kHz region somehow. ie.....
1. Tweeter that goes lower
2. Add a midrange
3. Smaller woofer
4. Listen off axis
That was my first idea (to ad a mid). If needed I would like to build an extra ''box'' containing a big mid range horn (à la Klipsch) sitting on my actual speakers boxes with a corresponding 3 way crossover. I will experiment very soon the Eminence. Thank AllenB.
Well, yes, but the eminence paper cone woofers climb the response above 2khz until rolloff at upper useable frequency. So they are more efficient 2k-4k even though the impedance is higher.
Note both drivers are 8 ohms & both ~95 db response. So they could match up without a resistor series the tweeter as is common in 2 ways with a louder tweeter. As the fostex can go down to 2.5 k, steeper filter than butterworth @ 3750 may not be necessary.
The 10" will beam a bit 3000-4000 hz. Some widening could be achieved by making the cabinet narrower at the back than at the front. Note with Qt of .59, a sealed cabinet is recommended by eminence.
One common ruggedizing feature is a 1 ohm tungsten filament bulb series the tweeter. If a huge high frequency signal occurs, as for example a cable becoming disonnected making a loud pop, this can protect your tweeter by increasing resistance as the current surges. These are sold at speaker components shops.
"will experiment very soon the Eminence."
Yes, that's a priority!
And what about woofer limits? The obvious One, and BSC Is an example for correcting (the C...) it, Is the losing in radiation efficiency when enclosed, the low freq. etc
So the necessity for the crossover network for 'contouring' the 'shape' ..the contribution of each driver to the final sound.
Indeed, aside the technical considerations ( yeah, phase Is important in the cross over region etc.), the target Is acoustical so you Better treat your ears (& C.) well
Yes, that's a priority!
Yes, steeper...
And what about woofer limits? The obvious One, and BSC Is an example for correcting (the C...) it, Is the losing in radiation efficiency when enclosed, the low freq. etc
So the necessity for the crossover network for 'contouring' the 'shape' ..the contribution of each driver to the final sound.
Indeed, aside the technical considerations ( yeah, phase Is important in the cross over region etc.), the target Is acoustical so you Better treat your ears (& C.) well
This is not criticism, but basics.
The crossover you posted is only theoretical. Speakers impedance changes with frequency, and frequency response is uneven. You have to take that into account and modify the crossover to get desirable final results.
Let's start with Eminence. It shows response rise from 1 to 3,7kHz with peak around 3kHz.
Since you going to use it "all the way" I see two solutions:
1. No crossover, just filter to smooth the response and use the natural rolloff for crossing. In that case tweeter should be 2nd order around 4,5kHz
2. First order x-over around 2,3kHz. It will smooth most the rise and combined with natural rolloff give 3rd order x-over slightly below 4kHz. In that case tweeter should also be 3rd order at 4kHz.
I recomend the second beacuse its simpler and gives better separation between drivers. Don't be affraid of 4kHz crossing. 4kHz/3rd order gives better protection to tweeter than 4,75kHz/2nd order.
I will try to make FRD and ZMA files from response curves and make some simulations.
It will be hard for tweeter beacuse graphs are low quality and I found two different specifications. One with 96dB and another with 98,5dB efficiency with slightly different frequency responses.
It will be good amount of guesswork, but
will reply in few days if I manage something.
The crossover you posted is only theoretical. Speakers impedance changes with frequency, and frequency response is uneven. You have to take that into account and modify the crossover to get desirable final results.
Let's start with Eminence. It shows response rise from 1 to 3,7kHz with peak around 3kHz.
Since you going to use it "all the way" I see two solutions:
1. No crossover, just filter to smooth the response and use the natural rolloff for crossing. In that case tweeter should be 2nd order around 4,5kHz
2. First order x-over around 2,3kHz. It will smooth most the rise and combined with natural rolloff give 3rd order x-over slightly below 4kHz. In that case tweeter should also be 3rd order at 4kHz.
I recomend the second beacuse its simpler and gives better separation between drivers. Don't be affraid of 4kHz crossing. 4kHz/3rd order gives better protection to tweeter than 4,75kHz/2nd order.
I will try to make FRD and ZMA files from response curves and make some simulations.
It will be hard for tweeter beacuse graphs are low quality and I found two different specifications. One with 96dB and another with 98,5dB efficiency with slightly different frequency responses.
It will be good amount of guesswork, but
will reply in few days if I manage something.
Ok, this is what I manage. X-over and response/impedance simulation in Boxsim. Its first order with response and impedance compensation for midbass and third order for tweeter with resistor in series to smooth the response. Electric x-over points (-3dB electric) are 2,8 and 4kHz respectively. Theres little gap between drivers responses so they actually cross at 3,8kHz.
For Fostex I found independent measurement graphs at this LINK
For Eminence I used factory graph for FRD and ZMA files. Eminence graph dont show phase responses, so result relies on simulated phase. Maybe you'll have to reverse the polarity of tweeter for optimum result. Feel free to experiment.
Midbass is simulated in 45 Liter closed box but it dont affect the crossover, different box can be used.
Parts guide:
0,47mH - resistance below 0,5ohm
0,33mH - resistance below 1ohm
3,3uF - MKT or MKP
8,2uF - MKT or MKP
22uF - bipolar elko
2,2ohm - MOX 10W
8,2ohm - ceramic 10W
For Fostex I found independent measurement graphs at this LINK
For Eminence I used factory graph for FRD and ZMA files. Eminence graph dont show phase responses, so result relies on simulated phase. Maybe you'll have to reverse the polarity of tweeter for optimum result. Feel free to experiment.
Midbass is simulated in 45 Liter closed box but it dont affect the crossover, different box can be used.
Parts guide:
0,47mH - resistance below 0,5ohm
0,33mH - resistance below 1ohm
3,3uF - MKT or MKP
8,2uF - MKT or MKP
22uF - bipolar elko
2,2ohm - MOX 10W
8,2ohm - ceramic 10W
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Thank you so much again Davor D. The two speakers are now on operation with my ''cheap and low cost'' crossover. What an improvement compare to the original woofer. I just made an order for ''serious'' crossover parts from Solen as you draw for me. And I'm already happy, but I'm convince thet the ''new'' crossover will improuve more the quality of sound.
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Thank you for update Godi!
I'am glad to hear new woofers are working much better than old ones. They look good too.
My x-over will give better transition between drivers and smoother response, but with little "sparkle" since you like presence. I hope you'll like it.
If not, you can adjust tweeter level by changing the 2,2 ohm resistance to any value between 0 and 4,7 ohm. For eg:
0 ohm gives +2dB
4,7 ohm gives -2dB
How's the bass?
Can you give me following dimensions:
bass vent inner diameter
bass vent lenght
box outer dimensions
box material thickness (if you know by chance. If not nevermind, it looks like standard 3/4in to me)
Iam curious about bass-reflex tuning, so I would like to calculate your box volume and check it.
I'am glad to hear new woofers are working much better than old ones. They look good too.
My x-over will give better transition between drivers and smoother response, but with little "sparkle" since you like presence. I hope you'll like it.
If not, you can adjust tweeter level by changing the 2,2 ohm resistance to any value between 0 and 4,7 ohm. For eg:
0 ohm gives +2dB
4,7 ohm gives -2dB
How's the bass?
Can you give me following dimensions:
bass vent inner diameter
bass vent lenght
box outer dimensions
box material thickness (if you know by chance. If not nevermind, it looks like standard 3/4in to me)
Iam curious about bass-reflex tuning, so I would like to calculate your box volume and check it.
It is a bit early to comment on the bass, I waiting for the crossover parts that I will definitely build. To my personal taste, the bass is a hair boomy and a hair lacking precision, but I'm convince that the new crossover will take care of that. So let's wait for the new crossover before acting on this issue.
The cabinet outside dimension are : 24 inch tall, 12 inch wide and 11 deep, of course with 3/4'' thick cabinet. The vent is 3 inch diameter and only 2 inch long, I would like to install a flare vent as this : https://www.amazon.com/Precision-Port-Inch-Flared-Tube/dp/B0002ZPR4W but I have no idea of the length to use ? I'm not a big fan of boum boum bass, I like it tight.
Here is a picture of my Outlaw RR2160 receiver, very clean 110 watts per channel at 8 ohm. I'm using a Pro-Ject turntable set-up with a red Ortophon cartridge, I'm not super happy with the phono stage result, But I don't know if the Ortophon is the problem or if the phono stage is not a good match, maybe I need a separate Phono stage preamp (like the https://www.schiit.com/products/mani ) ????? Compress music from You Tube sound better than a LP on my turntable, I'm lacking a bit of volume and the usual punch of a vinyl
Thank you again, Jean
The cabinet outside dimension are : 24 inch tall, 12 inch wide and 11 deep, of course with 3/4'' thick cabinet. The vent is 3 inch diameter and only 2 inch long, I would like to install a flare vent as this : https://www.amazon.com/Precision-Port-Inch-Flared-Tube/dp/B0002ZPR4W but I have no idea of the length to use ? I'm not a big fan of boum boum bass, I like it tight.
Here is a picture of my Outlaw RR2160 receiver, very clean 110 watts per channel at 8 ohm. I'm using a Pro-Ject turntable set-up with a red Ortophon cartridge, I'm not super happy with the phono stage result, But I don't know if the Ortophon is the problem or if the phono stage is not a good match, maybe I need a separate Phono stage preamp (like the https://www.schiit.com/products/mani ) ????? Compress music from You Tube sound better than a LP on my turntable, I'm lacking a bit of volume and the usual punch of a vinyl
Thank you again, Jean
Attachments
Did you correct for Baffle Step? The series coil seems small to me. Lozjek posted a scheme that makes more sense to me.
Crossover won't have effect on bass, it works in much higher range. Bass response depends on woofer specs and box properties.
Your box is 37Liter/1.3cu.ft. and 2in long vent gives tuning frequency Fb=59Hz.
For tight bass simplest solution is to close the vents and turn it into closed box. If you tightly plug both vents with bundle of thick socks it will show you the effect.
If you want to keep vented, for optimum results tuning should be little below woofers Fs beacuse Qts is little high.
5in long vent gives nice Fb=45Hz
Bass response will be almost identical as shown in simulation I aleady posted, with small 1,5-2dB rise in bass volume.
Regarding turntable, Ortofons have neutral balance, but depending on rest of the system they may sound analitic and cold. I had Series 500 on my Technics for years.
I'am not familiar with Outlaw electronics so I can't judge the phono stage quality.
If you seek for warmer cartridge Nagaoka MP-110 is popular choice these days for reasonable price.
No baffle step correction. For following reasons:
1. OP pictures shows speakers are placed against rear wall. And it looks like room is of average size. In such conditions baffle step will be much lower than theoretic 6dB.
2-3dB at most.
2. With 12x24in baffle, step will be centered around 300Hz. Driver response graph shows area below 300Hz has 1,5-2dB higher average otput than area between 300-1000Hz. So driver itself provides necessary BSC.
3. 10in driver will beam alot above 2kHz. Simple BSC will attenuate that area too, giving bigger of-axis response hole.
For same reason (better of axis response) I didnt make full correction of 5dB peak at 3kHz.
Also, last report by OP says bass is little boomy, which I expected since woofer Qts is little high. Plus, he wants strong midrange and likes presence. All that goes in favor against BSC.
I noticed Lojzek attenuated tweeter by 6dB, so it looks like he vent for theoretic 6dB BSC.
Thats valid for open space, but too much for average listening rooms and conditions.
Edit: 0,47mH is used to smooth the area above 1kHz. With little extra volume left for better of axis response.
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Agree on the suggestion to close the BR port. That doesn't do much good here. On baffle step correction, while Davor makes his point, I suggest experimenting with the series coil with values from 0,47 up to 1,5mH. Without measurements it's a question of tuning to taste anyway.
