I have JBL le14a ewave with the d220. Is this a similar idea? I used my old l55 cabs which I don't think are the idea cab size. Yours look much better!
As I understand it, the Econowave project began as a HF compression driver and waveguide based solution to any woofer in a box you had... Such as an original Advent etc. Then it snowballed into different versions designed by Zilch (RIP) and the experiences of others.
This lead way to people building off of the concept, tailoring things to different driver combos and whatnot. The idea of a large 2 way speaker goes backs fair ways before the Econowave, but it's safe to say the Econowave was a pretty inspirational project that not only taught, but inspired people who realized a good speaker can be DIY'd with minimal complexity, although it is a complex process.
For the LE14a, I would assume there is an ideal alignment and enclosure size for that driver. I would start there. Great unit to be working with BTW.
A little progress
Hi here...
I was lucky, the weather was somewhat good and perfect for cutting some sheet's outside last few day's
I'am actually satisfied with my cut's so far, but i'am for sure not the fastest Carpender around here... I would for sure be starving if this was my everyday work.
I used a lot of time getting the measurement's and marking right, someone here i read suggested using a knife for marking, and this is working way better than with good old pencil's.
Here this afternoon i "tested" my build to see if it would look right, and as i wrote earlier i am satisfied for now.
Jesper.
Hi here...
I was lucky, the weather was somewhat good and perfect for cutting some sheet's outside last few day's
I'am actually satisfied with my cut's so far, but i'am for sure not the fastest Carpender around here... I would for sure be starving if this was my everyday work.
I used a lot of time getting the measurement's and marking right, someone here i read suggested using a knife for marking, and this is working way better than with good old pencil's.
Here this afternoon i "tested" my build to see if it would look right, and as i wrote earlier i am satisfied for now.
Jesper.
Attachments
Hi here...
I was lucky, the weather was somewhat good and perfect for cutting some sheet's outside last few day's
Jesper.
Colored MDF baffle? Valchromat? Wish I could find that locally. Looks nice.
I'm getting a weekend alone in early May. Hoping weather will cooperate for me as well.
ultrachrome ::
Yes black HDF (HighDensityFiberboard)
This is a quote from Troels Gravesen's site
Good luck... Jesper.
Yes black HDF (HighDensityFiberboard)
This is a quote from Troels Gravesen's site
Tips and ideas Copyright 2012-14
Good luck... Jesper.
So I'm planning box construction and my cutsheet. I'm going to use a one piece front baffle for the wave guide and woofer with both recessed flush with the baffle surface.
But I also have a 4yo so I need a grill.
My current living room speakers, a pair of Klipsch KG4, have the baffle recessed about 5mm so that he's not able to simply pull off the magnetic grills. I see the Calpamos uses a similar style baffle.
Could this style of cabinet be used or could someone suggest a method? I'd prefer not to use the Mirage grill sock approach.
But I also have a 4yo so I need a grill.
My current living room speakers, a pair of Klipsch KG4, have the baffle recessed about 5mm so that he's not able to simply pull off the magnetic grills. I see the Calpamos uses a similar style baffle.
Could this style of cabinet be used or could someone suggest a method? I'd prefer not to use the Mirage grill sock approach.
I would insert small neodymium magnets in the front from the back so that you can then make a magnetic cover frame. I did the same with the Cerberus:
Cerberus - die etwas andere Bluetooth-Box - Der-Akustische-Untergrund
Unfortunately there are no real pictures of it.
Or you can get frame dowels like these:
LS-Rahmendubel-Set | Wireless Musiksysteme, Professional Audio, Buhne, DJ, Lautsprecher & Zubehor
This is how it was done with the JBL 4367.
Cerberus - die etwas andere Bluetooth-Box - Der-Akustische-Untergrund
Unfortunately there are no real pictures of it.
Or you can get frame dowels like these:
LS-Rahmendubel-Set | Wireless Musiksysteme, Professional Audio, Buhne, DJ, Lautsprecher & Zubehor
This is how it was done with the JBL 4367.
You have two options either getting a metal cover for the woofer as is used in car audio. Something like this:
https://www.amazon.com/Universal-Subwoofer-Speaker-Metal-Waffle/dp/B007ZDQ6AI
This will have to be drilled but will make the woofer virtually child-proof unless they use pins. Not optimal for sound and gives the woofer a PA/car-audio/industrial look but it works very well until the kids learn to use screwdrivers
Then there is the option of making a screen. Troels gives a nice description in his TL3 The-Loudspeaker-III and especially the Fusion Fusion with measurements. Also links for the stretchy material you use.
Then you have the option of going with neodym magnets as Troels does, or you can use the clip on dowels that Reese mentioned. Both work, magnets look classier (can be invisible) and re-attach by themselves often thwarting attempts of persistant children. Check polarity before gluing!!!!!
You could also use screws if you have a very curious and feisty child.
Good screens are not that easy to remove if you use enough magnets or clip ons, especially if the screen is a bit recessed like you see in the Klipsches with a lip. Having a plastic spatula can help get a recessed screen with strong magnets out and is another level of deterance to kids. In my experience the main benefit of screens is that it hides anything interesting. If you have a curious kid that sees the speakers pump it is very difficult to protect them with screens from scissors, sticks, etc. Best to hide that weird moving thing from the start!
Or you can go with the metal covers, they are usually good enough to keep drunk party-goers, cats, etc. away and the LaVoce speakers are weather resistant, so a splash of water might also be survivable. But if you play high volume the kids might still see the moving driver, but of course less so in a 15".
Kids do crazy things, I had a client who complained about terrible smell in the living room. Turns out the kid fed the "people singing in the box" sausages and candy through the BR tubes! The client liked the sound better so we ended up partially stuffing the BR tubes but had to replace all the damping inside the speakers, which was a Pain Advantage of closed boxes
Good Luck
https://www.amazon.com/Universal-Subwoofer-Speaker-Metal-Waffle/dp/B007ZDQ6AI
This will have to be drilled but will make the woofer virtually child-proof unless they use pins. Not optimal for sound and gives the woofer a PA/car-audio/industrial look but it works very well until the kids learn to use screwdrivers
Then there is the option of making a screen. Troels gives a nice description in his TL3 The-Loudspeaker-III and especially the Fusion Fusion with measurements. Also links for the stretchy material you use.
Then you have the option of going with neodym magnets as Troels does, or you can use the clip on dowels that Reese mentioned. Both work, magnets look classier (can be invisible) and re-attach by themselves often thwarting attempts of persistant children. Check polarity before gluing!!!!!
You could also use screws if you have a very curious and feisty child.
Good screens are not that easy to remove if you use enough magnets or clip ons, especially if the screen is a bit recessed like you see in the Klipsches with a lip. Having a plastic spatula can help get a recessed screen with strong magnets out and is another level of deterance to kids. In my experience the main benefit of screens is that it hides anything interesting. If you have a curious kid that sees the speakers pump it is very difficult to protect them with screens from scissors, sticks, etc. Best to hide that weird moving thing from the start!
Or you can go with the metal covers, they are usually good enough to keep drunk party-goers, cats, etc. away and the LaVoce speakers are weather resistant, so a splash of water might also be survivable. But if you play high volume the kids might still see the moving driver, but of course less so in a 15".
Kids do crazy things, I had a client who complained about terrible smell in the living room. Turns out the kid fed the "people singing in the box" sausages and candy through the BR tubes! The client liked the sound better so we ended up partially stuffing the BR tubes but had to replace all the damping inside the speakers, which was a Pain
Advantage of closed boxesGood Luck
Thanks Jazzfan, Rese66, and tubeglow. Lots of items to consider.
Magnets for sure. I've used those on another speaker.
Troel's TL3/Fusion style looks nice but more work. I have a lot of free time to plan but a lot less time to actually cut and assemble the cabinet.
Waffle style grills are bit severe for my taste, but now that I look again - for the 4th or 5th time - google is magically finding 15" options that use a finer mesh which looks nicer to my eyes. Pizza screen is clever!
These look like a good deal: 15" 2-Piece Black Steel Grill with Perforated Steel Screen - SGM15
But my main question was really about recessing the baffle and whether that would drastically alter performance. Calpamos does this and even skips flush mounting of drivers.
Magnets for sure. I've used those on another speaker.
Troel's TL3/Fusion style looks nice but more work. I have a lot of free time to plan but a lot less time to actually cut and assemble the cabinet.
Waffle style grills are bit severe for my taste, but now that I look again - for the 4th or 5th time - google is magically finding 15" options that use a finer mesh which looks nicer to my eyes. Pizza screen is clever!
These look like a good deal: 15" 2-Piece Black Steel Grill with Perforated Steel Screen - SGM15
But my main question was really about recessing the baffle and whether that would drastically alter performance. Calpamos does this and even skips flush mounting of drivers.
Of course there is an effect, but the horn is highly directive so it will not, actually be less affected by defraction on the edges of the speaker, as opposed to difraction at the horn lip, in my experience also diffraction in general. But horns have some other issues.
Ideally you would want to do something like the Vandersteen grills for the Quattro CT Quatro Wood CT | Vandersteen Audio
see pic 2. Where the frame of grills is the baffle of the speaker.
The main defraction will come from the speaker edges, even with speakers that are not flush mounted.
I'll quote Linkwitz here
"It has been my experience that the on-axis and off-axis frequency response of a given driver and baffle combination must be measured to assess overall uniformity of response, and that computer models give pessimistic predictions, because the underlying assumptions do not sufficiently describe the real acoustic behavior of drivers and of cabinet shapes. " Diffraction from baffle edges
So basically the effect of diffraction has to be accounted for in design and then checked in measurement. It should not lead to noticeable effects on the frequency response. Looks decent here. To massively lower diffraction you would need a large diameter curvature at the edges. Here the horn helps. Ask Rese about his considerations in the design.
Of course there are some issues with smearing due to diffraction but there are many forms of sound smearing to address. Primarily you deal with in room reflections, e.g. side walls and sofa to the wall /back wall reflections, rug on the floor if you don't have carpet, etc.
If you have a speaker edge or a lip around the speaker there will be a similar diffraction in the time domain there. These are usually fairly minor issues compared to wall reflections and especially speaker placement issues, IMO.
But then again there is a reason why Cabasse (ball type) speakers or large lipped horns sound so transparent and good, they have very little edge diffraction.
Cheers
Ideally you would want to do something like the Vandersteen grills for the Quattro CT Quatro Wood CT | Vandersteen Audio
see pic 2. Where the frame of grills is the baffle of the speaker.
The main defraction will come from the speaker edges, even with speakers that are not flush mounted.
I'll quote Linkwitz here
"It has been my experience that the on-axis and off-axis frequency response of a given driver and baffle combination must be measured to assess overall uniformity of response, and that computer models give pessimistic predictions, because the underlying assumptions do not sufficiently describe the real acoustic behavior of drivers and of cabinet shapes. " Diffraction from baffle edges
So basically the effect of diffraction has to be accounted for in design and then checked in measurement. It should not lead to noticeable effects on the frequency response. Looks decent here. To massively lower diffraction you would need a large diameter curvature at the edges. Here the horn helps. Ask Rese about his considerations in the design.
Of course there are some issues with smearing due to diffraction but there are many forms of sound smearing to address. Primarily you deal with in room reflections, e.g. side walls and sofa to the wall /back wall reflections, rug on the floor if you don't have carpet, etc.
If you have a speaker edge or a lip around the speaker there will be a similar diffraction in the time domain there. These are usually fairly minor issues compared to wall reflections and especially speaker placement issues, IMO.
But then again there is a reason why Cabasse (ball type) speakers or large lipped horns sound so transparent and good, they have very little edge diffraction.
Cheers
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Obviously the pizza screen/PA/ car audio type metal protectors will have the largest impact on diffraction, ask Rese if he thinks this might be an issue and also sound IMO and may change the profile of the woofer since it plays fairly high. I found the screen protectors impact sound the least when dealing with the lowest octaves.
I am not a huge fan of grills but they have the undeniable benefit of focusing less on the speaker and just letting yourself go into the music. It helps create the illusion of being there live and the music just being in the room. A bit like listening with eyes closed.
You have to decide its mainly esthetics probably and cost.
I am not a huge fan of grills but they have the undeniable benefit of focusing less on the speaker and just letting yourself go into the music. It helps create the illusion of being there live and the music just being in the room. A bit like listening with eyes closed.
You have to decide its mainly esthetics probably and cost.
I'm not sure that is obvious. Have you found this to be the case?
Some of what Linkwitz says may have been said in the context of dipole speakers.
@AllenB
This is related to experiences with PA systems for concerts and knowing DJs with their sound systems, meaning big PA systems for a gig. They avoid using the covers directly over the woofers for mids, opting for a screen over the front. It probably all depends on how the mesh and the mounting ring is made. Some manufacturers take the effect of a screen into their design. Something like that is really easy to test though. Have a friend mount and dismount the protectors (without you knowing which and place the spekers behind a screen or wear a blindfold and see if it changes anything for you. (real double blind)
Usually if you can go for a size bigger protector, but I don't think it would fit here. The least effects i have seen of the screens is when they were part of waveguids/horns without a mounting ring.
Linkwitz was speaking about baffles in general. OB or sealed makes no difference in my understanding of the topic.
This speakerdesign article also goes a bit into the frequency vs. baffle width and time delay. Mainly focusing on the inverse polarity of the edge diffraction on overall frequency. Understanding Cabinet Edge Diffraction nice measurements to demonstrate the point.
You like any designer just have to see if covers have an effect, and if this is a compromise you/your client/partner can live with. Horns are more directional so that is good. Since humans are most capable of hearing the most detail in the range of 800 - 7,000Hz, this is the worst place to have issues like diffraction. In the lowest octaves of the bass it is not that noticeable, if at all, here the usual real problems are room modes, speaker placement and seating position!!!
In my experience more than 80-90% of sound issues have to with room, speaker placement and seating positions, DSP can help but compared to a good room, placement and position there is always something off with correction and finding that right compromise while saving the "marriage" was one of the main tasks of installations.
If you like the protectors or need them, try to get ones that offer little resistance to air flow/reflections/do not move or flex or ring. Are big enough and do not have a noticeable/interfering mounting ring.
For screens I prefer a 45 degree bevel or a convex bevel towards the drivers for the frame (creating a type of waveguide) and then a speaker lip like those found on the Klipsch around for aesthetix with big speakers like the Asathor. Not sure it makes an audible difference but in my head I feel I did something and can live with it
[Best of course would be flush mounted screens (see Vandersteen CT) with a large diameter rounding...but that is difficult to impossible]
This has to with the fact the waveguides have a positive effect on diffraction, e.g. see Troels experiments Stepped Baffle Study
good luck
This is related to experiences with PA systems for concerts and knowing DJs with their sound systems, meaning big PA systems for a gig. They avoid using the covers directly over the woofers for mids, opting for a screen over the front. It probably all depends on how the mesh and the mounting ring is made. Some manufacturers take the effect of a screen into their design. Something like that is really easy to test though. Have a friend mount and dismount the protectors (without you knowing which and place the spekers behind a screen or wear a blindfold and see if it changes anything for you. (real double blind
)Usually if you can go for a size bigger protector, but I don't think it would fit here. The least effects i have seen of the screens is when they were part of waveguids/horns without a mounting ring.
Linkwitz was speaking about baffles in general. OB or sealed makes no difference in my understanding of the topic.
This speakerdesign article also goes a bit into the frequency vs. baffle width and time delay. Mainly focusing on the inverse polarity of the edge diffraction on overall frequency. Understanding Cabinet Edge Diffraction nice measurements to demonstrate the point.
You like any designer just have to see if covers have an effect, and if this is a compromise you/your client/partner can live with. Horns are more directional so that is good. Since humans are most capable of hearing the most detail in the range of 800 - 7,000Hz, this is the worst place to have issues like diffraction. In the lowest octaves of the bass it is not that noticeable, if at all, here the usual real problems are room modes, speaker placement and seating position!!!
In my experience more than 80-90% of sound issues have to with room, speaker placement and seating positions, DSP can help but compared to a good room, placement and position there is always something off with correction and finding that right compromise while saving the "marriage" was one of the main tasks of installations.
If you like the protectors or need them, try to get ones that offer little resistance to air flow/reflections/do not move or flex or ring. Are big enough and do not have a noticeable/interfering mounting ring.
For screens I prefer a 45 degree bevel or a convex bevel towards the drivers for the frame (creating a type of waveguide) and then a speaker lip like those found on the Klipsch around for aesthetix with big speakers like the Asathor. Not sure it makes an audible difference but in my head I feel I did something and can live with it
[Best of course would be flush mounted screens (see Vandersteen CT) with a large diameter rounding...but that is difficult to impossible]
This has to with the fact the waveguides have a positive effect on diffraction, e.g. see Troels experiments Stepped Baffle Study
good luck
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Yes, it's been known to make a difference. My concern was whether it would be due to diffraction or something else.
My concern was whether you can dismiss diffraction as nothing more than changes in response that you try to get balanced. The application of dipoles and practical monopoles tend to have differences which weigh into how acceptable this is.
It just changes the place where most of the diffraction happens, and can actually make the task more critical.
Probably a decent amount due to diffraction. Least effects are seen with flat mounting rings, recessed or pure mesh. If DJs need to use them for mids the tend to go a size larger to reduce the effects, e.g. 15" grill for a 12" woofer. There are probably a few effects between grills ringing/moving, air flow disturbances, reflections back into the driver and diffraction on the protector grills. I personally would avoid them for the critical ranges from 800-7K, but better avoid for 500-8K.
It definitely is more than just balancing out the frequency response, although that would be the largest most easily noticeable part. If you put the same speaker in a very large radius rounded baffle vs. edges there is more than just the ballanced frequency response. See Cabasse speakers when they do a demo on flat vs. their baffles/enclosures. There is just an improved clarity and rightness, something you find in the old Thiels or now the Vandersteens are good examples. In my experience our ears and minds are so soffisticated that we can hear small time alignment issues and also the smearing when echos or inverse phase responses come back to us. Also the enclosure vibrations. Its just less things the mind needs to process and easier for you to get into the music IMO. What do you mean with practical monopoles? Time aligned, fullrange, or coax? Or something else? and tend to have differences which weigh into how acceptable this is??? Could you phrase that differently.
It mostly depends on what is important for your ears to get you connected with the music. For me dynamics are extremely important and horns often get me there, (here a bit of low order distortion tends to help with diffraction and other issues) but I also like time aligned/point sources if they don't have huge issues, and tend to perfer a large speaker especially for piano and large instruments, here small speakers fail. Everybody is different.
Generally agree, but they often allow for easier time alignment and thus lower order crossovers and somehow the diffraction seems less noticeable if properly implemented IMO. (Probably better integration with the woofer and other effects as well) Also I don't know if this is because there is diffraction over a larger area and therefore less noticeable or if waveguides are just selected/designed for specific tweeter/midrange combos.
I have heard some odd diffraction by placing a semitube around/before the speaker edge and if not implemented correctly even eliminating too much diffraction or radiating energy by felt surrounds can suck the life out of the tweeter. WA does it well though. Probably some more aspects and combinations of enclosure and driver that are beyond me. Getting the right ballance, and not just the frequency response and radiation response is key, IMO
The grills arrived today. Open area seems to be 33% and 355mm diameter. If I understand correctly Sd 855cm2 is about 330mm diameter. Will be interesting to compare measured response with and without.
Drivers and crossover components scheduled to arrive tomorrow.
Still agonizing over how I want to build the cabinet. I like the idea of having the waveguide in its own box for future proofing but that does increase complexity.
I'll have the first weekend in May with the family gone to build the cabinets.
Drivers and crossover components scheduled to arrive tomorrow.
Still agonizing over how I want to build the cabinet. I like the idea of having the waveguide in its own box for future proofing but that does increase complexity.
I'll have the first weekend in May with the family gone to build the cabinets.
