First off, The Fusion amps have 15 biquads per channel. This means that the FA123 that I will be using has 15 biquads for each woofer and 15 for the tweeter.
In my understanding a biquad is a electrical second order filter or something like that. The fusion amp has them connected in series which allow to create higher order filters. This is from the QA in the manual for their filter design software:
Maybe that makes more sense to some of you than it does to me..
This is a list of "things" you can do with these biquads:
So as far as i can see you can create boosts and cuts. There is also a option for gain and delay on each channel (woofers and tweeter).
If you are interested then you can find the full manual for their software here:
https://www.hypex.nl/img/upload/doc/software/hfd/Documentation/HFD_4.4_Help.pdf
It still hasn't been updated for the FusionAmps in particular though. But if anything then they can do more.
Am I wrong thinking that these Hypex's can do anything I would want to do?
#jReave - I will do measurements! I am considering to buy a microphone, otherwise i will borrow one. The hypex software allows you to connect a microphone directly and do the measurments in the filter software. When you do this the software knows the drivers impulse response. Then the software shows you the expected result of your filters based on these measurments. So yes meassurments is indeed a must with this feature I think!
And thanks for the explenation on diffraction. It makes sense. So I will play around with that!
In my understanding a biquad is a electrical second order filter or something like that. The fusion amp has them connected in series which allow to create higher order filters. This is from the QA in the manual for their filter design software:
Maybe that makes more sense to some of you than it does to me..
This is a list of "things" you can do with these biquads:
So as far as i can see you can create boosts and cuts. There is also a option for gain and delay on each channel (woofers and tweeter).
If you are interested then you can find the full manual for their software here:
https://www.hypex.nl/img/upload/doc/software/hfd/Documentation/HFD_4.4_Help.pdf
It still hasn't been updated for the FusionAmps in particular though. But if anything then they can do more.
Am I wrong thinking that these Hypex's can do anything I would want to do?
#jReave - I will do measurements! I am considering to buy a microphone, otherwise i will borrow one. The hypex software allows you to connect a microphone directly and do the measurments in the filter software. When you do this the software knows the drivers impulse response. Then the software shows you the expected result of your filters based on these measurments. So yes meassurments is indeed a must with this feature I think!
And thanks for the explenation on diffraction. It makes sense. So I will play around with that!
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I have just talked to some friends that know much more about filtering than i do.
It seems that one Biquad has 2 poles and 2 zeros in filter terms. Using half a biquad will give you 1 pole and one zero. This can be used as a first order filter with a 3 db slope. Using a full biquad will give you two poles. If these are located at the same frequency this will give a second order filter with a 6db slope.
Since the 15 biquads are in series you can either keep combining them to increase the order of a filter or you can use it to create multiple different filters of 1 order or higher. This can then be used to dampen peaks and so on.
How they use them to make boosts i do not know.. Lowering everything else maybe?
Hope it makes sense. I am no filter expert. I am a mechanical engineer so all this electronics and filtering is pure hobby xD
The explenation above is how i understood a couple of electronics engineers throwing stuff at me
.
So as far as i understand there should be pretty many options with these Hypex amps built in DSP's or am i missing something?
It seems that one Biquad has 2 poles and 2 zeros in filter terms. Using half a biquad will give you 1 pole and one zero. This can be used as a first order filter with a 3 db slope. Using a full biquad will give you two poles. If these are located at the same frequency this will give a second order filter with a 6db slope.
Since the 15 biquads are in series you can either keep combining them to increase the order of a filter or you can use it to create multiple different filters of 1 order or higher. This can then be used to dampen peaks and so on.
How they use them to make boosts i do not know.. Lowering everything else maybe?
Hope it makes sense. I am no filter expert. I am a mechanical engineer so all this electronics and filtering is pure hobby xD
The explenation above is how i understood a couple of electronics engineers throwing stuff at me
. So as far as i understand there should be pretty many options with these Hypex amps built in DSP's or am i missing something?
Okay, then i will have to use plywood. I can unly find MDF in 6 mm and up. And i will prefer not to cut it to have maximum strength. No i will make the sides of more smaller layers.
Yeah okay so it is the quality that defines if it is good or not. not the location. Will have a look in Silvan then!
hmmm i think i am already in deep water with this cabinet design.. I have no idea how to determine the proper size and so on for the flow resistor.. I will definitively have to read mor about that before i can say if i can do it or not.
Can you descripe how it sounds different?
I never had them bottom out in the current cabinets. And as far as i know i have no protection against it. The new Speakers will be controlled via DSP and thus i will put in a highpass filter to protect them.
I know, speakers and sound are very subjective
The ones Scanspeak make are around 90-100 mm in diameter. For at midrange you only need one. But I think the Scanspeak ones are way to big for the 12W. It is quite a simple device, but it can be difficult to make one that has a even airflow. I think the midrange sounds more open and less congested than in a closed cabinet. But it can be argued that with a big cabinet, this will be a smaller issue. If you look a Troels never constructions, some of them have a short port filled with damping material. I would say this is not a true flowresister, but is has the same function. I have found that rockwool or similar works better than polyesterdamping. It is also some kind of rockwool that are in the Scanspeak types.
I dont think the 18W are perfectly fit to a closed cabinet. Better suited for a vented cabinet.
Du you have any idea how big it should be? Or how to calculate it?
I can see that the ScanSpeak is no longer in production.
I have a 3D printer and sometimes even a big CNC machine so if i could figure out how big it would need to be then i could easily build one myself, similar to the scanspeak with rockwool in between.
What happens if the mid cabinet is to big? I gues it is always possible to make it smaller, but if i should keep the volume of 1.5 l and still let it reach all the way to the back to use a flow resistor, then the whole mid cab will look like a port (long and thin). I guess that also aint dessireable?
Acording to WinISD it seem to be 50/50 with sealed or vented, maaaybe slightly better in vented. But i think i will go with vented for now. I can always block a hole and fill up volume, it is harder to go the other way.
I can see that the ScanSpeak is no longer in production.
I have a 3D printer and sometimes even a big CNC machine so if i could figure out how big it would need to be then i could easily build one myself, similar to the scanspeak with rockwool in between.
What happens if the mid cabinet is to big? I gues it is always possible to make it smaller, but if i should keep the volume of 1.5 l and still let it reach all the way to the back to use a flow resistor, then the whole mid cab will look like a port (long and thin). I guess that also aint dessireable?
Acording to WinISD it seem to be 50/50 with sealed or vented, maaaybe slightly better in vented. But i think i will go with vented for now. I can always block a hole and fill up volume, it is harder to go the other way.
Did not know the ScanSpeak ones is no longer in production. I think that original drawing of it is at good starting point. See here:
W1501/
Nice with a printer/CNC machine!!! Many DIYs dream.
If you make the volume bigger the Qtc will get lower and the Fb will be lower also. You can play with it here:
Speakerbuilder Pro 2.0
I think almost all contructions with 18W is vented.
W1501/
Nice with a printer/CNC machine!!! Many DIYs dream.
If you make the volume bigger the Qtc will get lower and the Fb will be lower also. You can play with it here:
Speakerbuilder Pro 2.0
I think almost all contructions with 18W is vented.
#digitalthor - With multiple subs, doo you then mean a sub for each speaker (a left and right channel sub) ?
Uuuh that is a very good offer, that i will most likely keep your word on!
#Rokytheman - That is what it looks like at least, found one place where it said no longer available and i can't find it on Scan-Speak's own site.
Didn't you say it would be to big for the 12W? what about 12WU?
Yes i certainly do not complain! only about the lack of time to use them!
The issue with WinISD and this one is that it barely covers the region whee i want to use the mid driver. Maybe some of the more advanced ones i was told about earlier does. Haven't had the time to look at them yet..
That have also been my impression except one of Zaphs projects:
Zaph|Audio - ZRT - Revelator Tower
Which does also seem to perform very well! .. But 38L !!
#eriksquires - Do you mean by filters and boosts?
Uuuh that is a very good offer, that i will most likely keep your word on!
#Rokytheman - That is what it looks like at least, found one place where it said no longer available and i can't find it on Scan-Speak's own site.
Didn't you say it would be to big for the 12W? what about 12WU?
Yes i certainly do not complain! only about the lack of time to use them!
The issue with WinISD and this one is that it barely covers the region whee i want to use the mid driver. Maybe some of the more advanced ones i was told about earlier does. Haven't had the time to look at them yet..
That have also been my impression except one of Zaphs projects:
Zaph|Audio - ZRT - Revelator Tower
Which does also seem to perform very well! .. But 38L !!
#eriksquires - Do you mean by filters and boosts?
Yeah you definitely don't want to use the 12M, it's a big waste of money. The 12MU is a different story altogether though.
Personally I'd look at using mids and woofers from SBs satori line. Possibly with their Be tweeter, or a small format Be/cloth dome from Scan speak. The D3004/604010 for example. No point in using a large faceplate tweeter with a small mid, you want to get that centre to centre distance as low as possible!
Personally I'd look at using mids and woofers from SBs satori line. Possibly with their Be tweeter, or a small format Be/cloth dome from Scan speak. The D3004/604010 for example. No point in using a large faceplate tweeter with a small mid, you want to get that centre to centre distance as low as possible!
For this project i would like to keep the tweeter and woofer. However, the mid is a different story.. I love the look of the 12M but it does not seem like people like it so much, and if the 12MU is the same price i see no reason not to use that one.
Would you say a 5in SB Satori would do good as mid as well?
I really do like the SB Satori line and the specs look crazy! I think i will try some simulations on those just for fun and future projects (Car for example )
Would you say a 5in SB Satori would do good as mid as well?
I really do like the SB Satori line and the specs look crazy! I think i will try some simulations on those just for fun and future projects (Car for example
)I stand corrected on those amps. Now that I know what biquads are (thanks Danner), they do in fact look like they will do the job just fine. Everything perhaps except for time/phase alignment but with your tilted baffle more or less physically aligning your drivers' acoustic centers, that should hopefully take care of that.
Re the mid chamber - a tapering long rear chamber properly stuffed is actually a good thing for reducing back wave reflections. Also don't be afraid of a larger mid chamber. Think of running mids open back - they are seeing essentially an infinitely large rear chamber. My own design philosophy makes use of high density, rigid rockwool. I take the recommended Vb with Q =~ .7 from a box program like WinISD and then double it or thereabouts and then fill about half or maybe a bit more than half with the high density insulation, maybe 3" - 5" on the back wall and 1.5" on all other walls. Depth may be dependent on the lower xo frequency. Stuff the remaining volume with foam and/or polyfill as you normally would. Works very, very well.
Re sealed or vented - there are pros and cons to each so depends where your priorities are. Zaph's measured TS parameters are just a little different than ScanSpeak's which is the reason for 38L sealed vs about 31L for Q=~.7
For your situation, the option for use with or without subs and your maximum desired SPL make be key factors in your decision. For eg, if you were always going to use them with a sub and didn't need crazy SPL levels, you could easily get away with one 18W sealed. The 2nd order sealed rolloff tends to integrate better with a sub, F3 is in the 60Hz range, no bass boost required, transient response is improved and you now have some extra volume to oversize your chambers and stuff them more aggressively.
On the other hand, if you wanted the option of being able to use them sans sub, vented would be the way to go.
Re the mid chamber - a tapering long rear chamber properly stuffed is actually a good thing for reducing back wave reflections. Also don't be afraid of a larger mid chamber. Think of running mids open back - they are seeing essentially an infinitely large rear chamber. My own design philosophy makes use of high density, rigid rockwool. I take the recommended Vb with Q =~ .7 from a box program like WinISD and then double it or thereabouts and then fill about half or maybe a bit more than half with the high density insulation, maybe 3" - 5" on the back wall and 1.5" on all other walls. Depth may be dependent on the lower xo frequency. Stuff the remaining volume with foam and/or polyfill as you normally would. Works very, very well.
Re sealed or vented - there are pros and cons to each so depends where your priorities are. Zaph's measured TS parameters are just a little different than ScanSpeak's which is the reason for 38L sealed vs about 31L for Q=~.7
For your situation, the option for use with or without subs and your maximum desired SPL make be key factors in your decision. For eg, if you were always going to use them with a sub and didn't need crazy SPL levels, you could easily get away with one 18W sealed. The 2nd order sealed rolloff tends to integrate better with a sub, F3 is in the 60Hz range, no bass boost required, transient response is improved and you now have some extra volume to oversize your chambers and stuff them more aggressively.
On the other hand, if you wanted the option of being able to use them sans sub, vented would be the way to go.
#jReave - Glad to hear you changed your mind! They do have some kind of delay function but that may not be enough? But good i have the tilt then!
Hmm okay, good to know about the mid chambers. Thanks!! My conclusion from the speakerbuilder software was also that for a speaker playing above 400Hz it does not really matter that much how big the chamber is. At least not from what i can see.
Aaaah okay. Still a bit big for me.. I would prefer not to have a sub at all so if i can make the vented 18W sound good enough for me (which i have af feeling i can) then i think that will be the best for me!
Thanks for the inputs!
Hmm okay, good to know about the mid chambers. Thanks!! My conclusion from the speakerbuilder software was also that for a speaker playing above 400Hz it does not really matter that much how big the chamber is. At least not from what i can see.
Aaaah okay. Still a bit big for me.. I would prefer not to have a sub at all so if i can make the vented 18W sound good enough for me (which i have af feeling i can) then i think that will be the best for me!
Thanks for the inputs!
Haha - well - it's not allways this easy
I tried to read Geddes white papers, but I'm still at a learning curve. All I can say, is that it mostly works really well and better than just to typical speakers, when it comes to bass performance in typical listening rooms.
I mean 2-4 subs, that is driven from arond 80-90hz and down i the modal region(meaning where wavelength is so long, that we cant hear from where it comes). Your 18W will sound better with no deep bass duty and the subs integrate much better in the room, when they are placed differently than your front speakers - below 90hz or so - ofcourse.#digitalthor - With multiple subs, doo you then mean a sub for each speaker (a left and right channel sub) ?
Uuuh that is a very good offer, that i will most likely keep your word on!
Just PM me and we'll figure out something
The DSP will allow to set the delay and phase. Therefore (with DSP) there is no need to complicate the box with a slanted or stepped front bafle , that is one of its' advantages.
Do set the correct delay first, then proceed with the electrical transfer functions (and EQ if needed) to match your acoustic targets.
Danner,
Before this thread dies out, I was just looking over your cabinet design a little closer.
Consider that the footprint of the design is determined by the base dimensions and not the actual cabinet width. If it doesn't mess up the aesthetics too much for you, I would think you could go just a little bit wider with the cabinet to obtain a little bit more cabinet volume without increasing the width of the base. Normally I would suggest going deeper or taller but with your rearward cabinet tilt, both of those things may be more difficult for you to swallow given your size constraints. Just a little bit more cabinet width should allow you to go deeper with your mid chamber while still leaving enough room at the back for the continuation of the woofer chamber.
Maybe I would also try to add in another brace in the woofer section and I don't see many other people doing this but I also like to reduce the woofer SPL behind the tweeter (ie. it's pretty easy for low frequencies to pass through a thin piece of metal) by adding an extra piece of wood behind it to seal it within its own tiny chamber.
Otherwise it looks like a pretty solid design.
Before this thread dies out, I was just looking over your cabinet design a little closer.
Consider that the footprint of the design is determined by the base dimensions and not the actual cabinet width. If it doesn't mess up the aesthetics too much for you, I would think you could go just a little bit wider with the cabinet to obtain a little bit more cabinet volume without increasing the width of the base. Normally I would suggest going deeper or taller but with your rearward cabinet tilt, both of those things may be more difficult for you to swallow given your size constraints. Just a little bit more cabinet width should allow you to go deeper with your mid chamber while still leaving enough room at the back for the continuation of the woofer chamber.
Maybe I would also try to add in another brace in the woofer section and I don't see many other people doing this but I also like to reduce the woofer SPL behind the tweeter (ie. it's pretty easy for low frequencies to pass through a thin piece of metal) by adding an extra piece of wood behind it to seal it within its own tiny chamber.
Otherwise it looks like a pretty solid design.
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