I am using the GRS PT6825-8 8", the wide version, not the skinny version which starts to diverge off axis @4kHz and peak and roll off at 10-12kHz.
I am crossing over to the ribbon before the midrange's off-axis plots start to diverge significantly.
The ribbons go to 40+kHz (assuming the upstream provides frequencies that high). I run at 176.4kHz sample rate.
That being said, the GRS sounds good by themselves with old ears that no longer go to 20kHz. =)
I physically located the ribbon as close to the midrange as I could without magnetic interference between the 2. This has improved the midrange/tweeter XO region off axis response by at least an octave over stock by shortening the center-2-center to 4".
I would have liked to have located them directly beside each other but decided not to for the magnetic field and baffle structural issues. That would have improved the XO region off axis response by almost another octave. Center-2-center would then be 2.5" butted up against each other.
I am currently welding up the base feet. Hopefully the narrow baffles won't be tipsy.
I am thinking about 10*PT6825 as a line array in a open-baffle of +/- 40cmx220cm. I will use DSP and it looks like the part above 10KHz can be equalized.
I am now experimenting with the shape of the baffle to optimize the initial frequency response.
An other question to the readers of this thread: It seems you can buy a copy of the PT6825 at alibaba (PT6825 clone?) for half the price.
Any one has experience with these? I think I will order a pair and measure them...
That looks nice! But I did not do the accounting but this could be rather costly if you make this 2 meters high? So cost is one of the reasons
You don't have to make a 2 meter version, you could get inspiration from this thread: https://www.audiocircle.com/index.php?topic=159717.0
and the image comes from this video - they are called the GR Research Line force:
The reason I recommend using both is a much better and wider dispersion, using only the 8" or 10" will produce to much beaming, like a needle, above 10kHz and that is not pleasing.
and the image comes from this video - they are called the GR Research Line force:
The reason I recommend using both is a much better and wider dispersion, using only the 8" or 10" will produce to much beaming, like a needle, above 10kHz and that is not pleasing.
There have been a lot of offshore clones come and go over the years with varying quality/performance. Hopefully the Parts Express GRS models will provide some consistency/stability in their quality and availability should one need any replacement drivers down the road. They have carried GRS cone drivers for a while now, much longer than the planar drivers. Not to mention the real original NEO's are no longer being sold to the public.
I second looking at the LineForce threads for ideas. Also, take a look at the Mockingbird LSX Line array, another of Danny's designs using both cones and NEO8's. There is more than one thread on the LineForce including a very recent build in the break-in stages. HAL on that forum made a tall pair by using NEO 10's and a different brand of ribbons using digital XO's.
If you plan on making a tall version, spend a bit of time designing a rigid baffle. Danny's design uses a deep wing on the midrange side which adds rigidity to the front baffle. My baffle is fairly rigid, but I decided (after testing with steel bases) I am going to add struts in the back similar to the MyeStands to prevent sway because they are so narrow and tall. The baffle is 86" tall above the base stand to center the drivers vertically on an 8' ceiling.
Mockingbird LSX:
Hal's Megalith (NEO10 and Ribbons):
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You might want to talk with WrineX if you are considering building your own planar drivers.Found the tread a few minutes ago, but thanks
I am extremely curious about this type of loudspeaker, even considering building my own planar magnetic drivers. When honed in, that should give me a stellar quality control.
I have communicated a few times
following him on YT and FB. There is a great deal to learn when it comes to planar magnetics, so looking at what others are doing is an absolute must.
Found an interesting comment on one of Joppe's videos where he dissects a B&G Neo 8.
We can even see the to be released 10" in this picture with is found on Radian's front page, but no info on their planar product page.
Source:
https://audioxpress.com/article/tes...r-and-waveguide-from-radian-audio-engineering
https://radianaudio.com
That looks to be fairly accurate and Radian are working on a 10" version which they informed me of a few months ago. Together with their very nice LT2, I am looking forward to the 10". These should be a direct replacement for the original B&G.
We can even see the to be released 10" in this picture with is found on Radian's front page, but no info on their planar product page.
Source:
https://audioxpress.com/article/tes...r-and-waveguide-from-radian-audio-engineering
https://radianaudio.com
Actually, there was full data sheet download Friday. That link is dead now. And it's listed for sale at $249.
This link seems to be working and with updated information, got it from Radian a couple months ago:
https://cdn.shopify.com/s/files/1/0111/0324/0254/files/LM10n-datasheet-v2.pdf?v=1666125534
Very interesting driver, but it will get expensive in a line array, so better DIY, which is my plan
https://cdn.shopify.com/s/files/1/0111/0324/0254/files/LM10n-datasheet-v2.pdf?v=1666125534
Very interesting driver, but it will get expensive in a line array, so better DIY, which is my plan
Thanks for the link, and oh absolutely. Doing a Line-Source like the LineForce is too expensive for my comfort, meaning I will need to develop & construct my own drivers like you. Its not happening for a few years, I am taking a step down from audio and go full focus on saving up to a house.
Btw. The way I separate Line Array and Line Source is:
Line-Source is made up of different drivers on the horizontal plane such as tweeter and midrange and repeated vertically.
Line-Array are made up of different drivers but does not repeat horizontally, only vertically. MTM or WMTMW is considered Line-Array.
Btw. The way I separate Line Array and Line Source is:
Line-Source is made up of different drivers on the horizontal plane such as tweeter and midrange and repeated vertically.
Line-Array are made up of different drivers but does not repeat horizontally, only vertically. MTM or WMTMW is considered Line-Array.
The Radian LM10N is now official, not found under the planar section yet, but it sits in the general products page. So together with this and the LN2, if one wants to, one could build the LineForce.
https://radianaudio.com/products/lm...ribbon-transducer?_pos=1&_sid=6916d27af&_ss=r
https://radianaudio.com/products/lm...ribbon-transducer?_pos=1&_sid=6916d27af&_ss=r
Some minor updates.
When we replaced our old single-panel wood garage doors, I saved the old steel mounting hardware assuming the scrap metal would have a second life in the shop sooner or later. Well, it is later and it won't be the shop.
These are 3/16" inch thick plates that will bolt to the bottom back of the baffles and pedastal feet. I welded the original bolt pattern shut, cut to size (tried Diablo's new Steel Demon blades which worked surprisingly well) and then drilled new bolt patterns for the narrow baffles with threaded metal inserts.
I will be using wood pedestal feet, but could weld on steel feet in the future if desired. Either will have leveling spike options.
(left gray is the modified and primed bracket, right black is the original scrap minus the hinges and angle iron).
I am not a spray painter (other than house & fence paint). I have been playing around with paint options and am leaning towards an analyzed red over metallic silver to contrast the black drivers. Here is a sample sealed MDF cut off using Rustoleum's hammered silver as an undercoat and Duplicolor's Metalcast Anodized Red translucent top coat. No clear coat yet, but considering a 2K variant with hardener.
I have discovered various paints don't play well together and lift the undercoats. Also discovered that paint prices are fluctuating widely, currently North of sanity.
Once the paint is on and dried, I am ready to mount and wire the drivers.
When we replaced our old single-panel wood garage doors, I saved the old steel mounting hardware assuming the scrap metal would have a second life in the shop sooner or later. Well, it is later and it won't be the shop.
These are 3/16" inch thick plates that will bolt to the bottom back of the baffles and pedastal feet. I welded the original bolt pattern shut, cut to size (tried Diablo's new Steel Demon blades which worked surprisingly well) and then drilled new bolt patterns for the narrow baffles with threaded metal inserts.
I will be using wood pedestal feet, but could weld on steel feet in the future if desired. Either will have leveling spike options.
(left gray is the modified and primed bracket, right black is the original scrap minus the hinges and angle iron).
I am not a spray painter (other than house & fence paint). I have been playing around with paint options and am leaning towards an analyzed red over metallic silver to contrast the black drivers. Here is a sample sealed MDF cut off using Rustoleum's hammered silver as an undercoat and Duplicolor's Metalcast Anodized Red translucent top coat. No clear coat yet, but considering a 2K variant with hardener.
I have discovered various paints don't play well together and lift the undercoats. Also discovered that paint prices are fluctuating widely, currently North of sanity.
Once the paint is on and dried, I am ready to mount and wire the drivers.
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Some of the newer professional paints are pretty nasty from a health standpoint. This is mostly referencing your 2k with hardener comment. Depending on what and where you are painting, a disposable respirator of the appropriate type may be in order at a minimum. And that "of the appropriate type" is important - you're dealing with a chemical hazard, not just particulates.
As a hobbyist, I'd stick with paints you can get at typical retail outlets, and stay away from anything with a terrifying SDS.
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I have seen the recommendations online about proper ventilation and filtration with 2K paints/clears. I have shop fans, cross ventilation and a fairly descent mask with dual screw on filters. I will probably setup a vented/filtered paint tent to control the dust. The 2K clears are also supposed to be much better finishes than the 1-part clears but have a very short shelf life once mixed.