Full Range TC9 Line Array CNC Cabinet

Interesting, looks like they have made a sandwich of an outer baffle with roundover which maybe holds the driver down and the glue acts as a gasket. How do you then isolate the face baffle from everything else? This is why I couldn't find something simple.

Could you use the gasket along the back and then use screws that have a small isolation washer sandwiched between the screw head and the frame? It would stick out a little bit. And perhaps not truly isolated. But it's pretty simple. Or maybe a small o-ring?
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Interesting, looks like they have made a sandwich of an outer baffle with roundover which maybe holds the driver down and the glue acts as a gasket. How do you then isolate the face baffle from everything else? This is why I couldn't find something simple.

Are you thinking about a Line array Mark 2 like you mention in that thread? ;)

I believe they add a gasket material (called VS foil but not sure that is a specific name or anything) on the back side of the driver cover baffle, which is just pressure fit against the front of the drivers :confused:

If I get around to a mk2 build the internals of that build is something I would seriously consider...or a curved cabinet like wesayso ;)
 
Could you use the gasket along the back and then use screws that have a small isolation washer sandwiched between the screw head and the frame? It would stick out a little bit. And perhaps not truly isolated. But it's pretty simple. Or maybe a small o-ring?
An externally hosted image should be here but it was not working when we last tested it.

That's what I use to fasten my "double baffle" to the enclosure. With damping in front and to the rear of the "floating" inner baffle that has the drivers bolted to them.

Again, checked with impedance measurements. A measurable difference compared to just bolting it down. I used rubber rings made from an old inner tyre first, also tried neoprene rings.

Here's proof of the tests:
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:)
 
I believe they add a gasket material (called VS foil but not sure that is a specific name or anything) on the back side of the driver cover baffle, which is just pressure fit against the front of the drivers :confused:

If I get around to a mk2 build the internals of that build is something I would seriously consider...or a curved cabinet like wesayso ;)

I don't plan to have a double baffle at this point but it is still possible to be retrofitted later if I felt it was needed.

I also really wanted to make a curved cabinet using the frame and laminated ply sheets, partly because I have a few sheets of 3mm luan ply that I got for nothing, turned out to be too much work at this point though.
 
Rubber Damping Cut

Some progress today, I have cut the rubber sheet up into the correct size segments to go on the side walls.

Sorry for the grainy pictures. The rubber is now sandwiched between the cabinet parts for a few days to try and take out the slight bend in it from being stored rolled up for a long time.

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I hope we aren't keeping you from the actual build :), I can hardly wait!

(I typed too soon, progress! :D)

No I am trying to avoid paralysis by analysis wherever possible :)

Next is to get the top and bottom plates glued together and some dowel holes drilled in the sides for alignment and strength when glued. These are the parts that are hard to get done by CNC as they are on the edges.

I have had to think of how I can glue it up in stages as it takes a lot of clamps, I have quite a few but not enough to do a full cabinet all at the one time properly. Because of the length of the panels I really need two clamps per brace along with almost the same amount again front to bak to keep everything aligned.

My plan is to
1. glue the top and bottom parts to the side with the dowels,
2. glue the back on
3. glue the braces in (then organise the wiring and fill with damping)
4. glue the front baffle on with some dowels for strength and alignment
 
I won't be able to do much more in building the arrays for a few days so I thought that I would post some information on the speakers I have been using up to now.

I have built two sets of Linkwitz dipoles. I started with Orion, an analogue crossover and LM4780 chipamps. The original painted MDF cabinet I made took some damage when moving house so I rebuilt the cabinet in a different style using hoop pine plywood and solid oak strips. I think it looks much better. It is hard to compare the sound as I have never heard the different cabinets in the same room. I also put the crossover in a nicer looking case.

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As is always the case it took me so long to make the first Orion cabinet that Linkwitz had come up with a new version by the time I was finished. The LX521 was supposed to be better so I decided to build one and see. I wanted to use a DSP as the analogue crossover had become expensive and limited, Najda fitted the bill so I built one into a case with a linear power supply. I felt the chipamps were a little underpowered and could trigger the spike protection before the woofer gave out so I built an 8 channel Hypex amp to allow the LX521 to become 4 way active. There is also a picture of the LX521 in my current living room.

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I was really impressed with Orion when I first built them, partly because it was the first really top notch system that I had owned, it was truly full range in comparison to the bookshelf speakers I had before and the room they were in let them work very well. The right channel had the rear wave firing into an adjoining room, the left channel also had plenty of space to the side wall and there was a good distance behind the listening position to the rear wall so there were limited early reflections.

I had moved twice by the time LX521 was completed fully and the room they are now in is much less dipole friendly. Rear wall is closer, side walls are closer and the rear wave contributes much more with a reflection off the front wall. The 45 degree toe in and dipole nulls to the side help control the side wall reflections and limit the damage from the TV and cabinet to some extent. Due to the dimensions of the room and the fact that it is smaller lead to a few bass notes being boomy until the placement was tweaked a little to minimize the effect from room boundaries.

What I have found is that a dipole with enough room to breathe is a really natural sounding speaker that works with any style of music that I listen to.

The dipole in a more constrained room like I have now is more hit and miss. Jazz and acoustic music is magical the clarity and precision of the LX521 is outstanding. Almost too good as I have been able to hear issues with the recording of certain records which I had not noticed before even when listening on good headphones. The full range dipole with rear firing tweeter seems to be able to amplify some types of distortion, my Orion with no rear tweeter is more forgiving in this regard.

What seems to happen to rock music is that it sounds like too much reverb has been added to the mix. Jazz and acoustic music sounds spacious, rock sounds muffled and muddy in comparison.

I have experimented a little by placing some egg crate foam panels behind and a little to one side of the cabinets on the front wall, this helps and reduces the extra reverb effect somewhat.

The bass that the two 10" SEAS woofers can put out is quite impressive and without a high pass filter goes all the way down.

The LX521 has less dipole boost down low in comparison to Orion, I used the DSP to create a digital crossover for Orion and it was not as good as the analogue one. I found it very hard to avoid clipping in the DSP with bass transients and it was often tracks that I wasn't expecting to clip that did it. I had to apply too much digital attenuation and even with the analogue volume control in Najda with 15dB of boost to make up the gain, resolution was lost in the converters and it just sounded wrong. The analogue crossover had no issues with the boost needed.
 
I found two tracks to be very useful in testing the low frequency capabilities.

One is "Hold Back the River" by James Bay.

https://www.youtube.com/watch?v=mqiH0ZSkM9I

I really like this song, the acoustic space is quite appealing and this sounds amazing with LX521. The double bass has some really difficult transients, this is the track I had the most trouble with clipping the DSP.

The other is "Free" by Rudimental feat Emeli Sande.

https://www.youtube.com/watch?v=KDPW_g2AhAU

This track has a significant amount of very low frequency energy in a synthetic base line. It really makes the dipole woofers move!

This is the spectrum from Audacity

Free Spectrum.JPG

Wesayso if you are reading this have you tried either of these two tracks on your arrays? If you have I would be interested to know how they handled them.
 
This is going to be interesting. I've seriously considered the Orions before I started on the Array trail. I just figured that my room would be too small to make it work.
I'm curious to find out what you'll think of this array setup. It will be different. That's for sure. Will it be a good kind of different? :)
Take your time, the different sounds I have heard made me rethink what balance can do. I've heard so many different presentations, it 'll be a good idea to stick with it and find your way.
I've had moments where I thought: this isn't going to work. Changing only a few details made a world of difference. Avoiding early reflections is key. Get the room to play with the arrays, you're avoiding two mayor draw backs of most speakers. The floor and ceiling reflections. From the first moment of sound, I knew it could be something special. But it took quite a while to get me satisfied, stick with it!
 
I found two tracks to be very useful in testing the low frequency capabilities.

One is "Hold Back the River" by James Bay.

https://www.youtube.com/watch?v=mqiH0ZSkM9I

I really like this song, the acoustic space is quite appealing and this sounds amazing with LX521. The double bass has some really difficult transients, this is the track I had the most trouble with clipping the DSP.

The other is "Free" by Rudimental feat Emeli Sande.

https://www.youtube.com/watch?v=KDPW_g2AhAU

This track has a significant amount of very low frequency energy in a synthetic base line. It really makes the dipole woofers move!

This is the spectrum from Audacity

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Wesayso if you are reading this have you tried either of these two tracks on your arrays? If you have I would be interested to know how they handled them.

I'll hunt them down and listen... :)
 
This is going to be interesting. I've seriously considered the Orions before I started on the Array trail. I just figured that my room would be too small to make it work.
I'm curious to find out what you'll think of this array setup. It will be different. That's for sure. Will it be a good kind of different? :)
I really hope so because the footprint of the arrays is much more living room friendly and I am looking for something that will be a better background music system as well as for critical listening.

It will be interesting to see if the arrays can compete or better the LX521 in terms of fidelity.

Take your time, the different sounds I have heard made me rethink what balance can do. I've heard so many different presentations, it'll be a good idea to stick with it and find your way.
I've had moments where I thought: this isn't going to work. Changing only a few details made a world of difference. Avoiding early reflections is key. Get the room to play with the arrays, you're avoiding two mayor draw backs of most speakers. The floor and ceiling reflections. From the first moment of sound, I knew it could be something special. But it took quite a while to get me satisfied, stick with it!

What I learn from measuring and processing the arrays may also benefit the dipoles later down the track. Different approaches to some things though because the dipoles are designed to be used in a more reflective room. First reflections would also be different due to the directivity.

To round out the directivity triangle I also have a small Synergy or two planned, I already have the XT1464 horns and for the more normal Synergy, Celestion compression drivers and Aurasound 2" drivers.

These are now a more distant project with the arrays being the focus.

Maybe a directivity death match is on the cards for a year or twos time... or three or four.... :D
 
Thanks fluid open up sharing data and thoughts for previous and upcoming system setups, feeded with this info too feel is going to make thread even much more interesting :) and look forward down the road hear and see those systems compared objective and subjective.

Had a listen the two YT tracks and guess much will depend if LX521 have FIR or IIR XO regions, from own tests with all-pass filters if LX521 have ordinary IIR XO then full range TC9 arrays will gain much more realism because of better timing having no XO. That said having heard only few OB setups and mostly it be enclosures for musical instruments in a rehearsal room, know those can also sound very real and pleasing.

We probably need some patience before more feedback from Netherlands :D
 
Thanks fluid open up sharing data and thoughts for previous and upcoming system setups, feeded with this info too feel is going to make thread even much more interesting :) and look forward down the road hear and see those systems compared objective and subjective.

Had a listen the two YT tracks and guess much will depend if LX521 have FIR or IIR XO regions, from own tests with all-pass filters if LX521 have ordinary IIR XO then full range TC9 arrays will gain much more realism because of better timing having no XO. That said having heard only few OB setups and mostly it be enclosures for musical instruments in a rehearsal room, know those can also sound very real and pleasing.

We probably need some patience before more feedback from Netherlands :D

The LX521 is IIR with digital delays and no all pass, Orion is analogue with all pass filters to time align. Both have a considerable amount of EQ to compensate for the dipole rolloff as well as some mild EQ for driver correction.

Both could have a rephase filter created to undo the phase turn or a full blown linear phase FIR version created. I can't see myself making a linear phase crossover though as it doesn't make sense to me, too many taps needed to control the dipole EQ down to nearly DC.

Others have made efforts to make linear phase versions and I don't hear much from them saying it is any better. I wonder if the benefit comes when you have controlled the early reflections or avoided them by near-field listening like you do. Perhaps the more reflective in room nature of the dipole masks the benefit you and wesayso have found, just speculation though.

I also am starting to think that I am listening to things differently to some other's, maybe what I am listening for is not what they are listening for. I hear a lot of talk of massive differences from oscillators, power supplies, isolating and reclocking, buffer size, the type of computer media program that is used. I don't find much of these to make huge changes, differences yes but sometimes difficult to even say which one I actually prefer.

I have not been particularly interested in stereo imaging as I often find it distracting and false. Although the LX521 has excellent imaging. I started as a musician (drummer) and moved through audio engineering to now making diy equipment for myself. I find it weird that the hi-hat is almost always panned hard right (to me it should be on the left but not hard left only because that is where I sit!) and the drums are separated over almost three metres if the speakers are that far apart. When I play a drum kit I hear none of this, the locations are no more than a metre apart. Spaced stereo overheads increase ambience but make the spread worse. Very few recorded drum sounds bear any relation to the actual acoustic event unless it is a jazz record or maybe Led Zeppelin. By the time it has been damped, gated compressed and EQ'd it is totally unrealistic. I spent the first 5 years of playing wondering what I was doing wrong as I couldn't get my drum kit to sound like any record I had heard!

What I am interested in is tone and timbre, so I think that a flat frequency response (falling at higher frequencies) and avoiding too many early reflections should get me closer to what I want.

I'm sure others feel differently.
 
Hi fluid that is very interesting hear a drummers views and some good points there regarding hi-hat, have a thought we never going to hear symbols be 100% realistic because of real speakers HF roll of makes squarer waves transients fade out above 4-6kHz area and diamond tweeters won't move much there in it will need far bigger steps to improve square waves up to say 20kHz area. My DSP run at 192kHz so can load a Rephase filter than turn phase up there and while i think it helps a bit isolated focus on symbols realism it ruins overall rhythm musicality for recording, compared to fully mic'ed live concert reproduce drums at home is good enough it gets harder to reproduce the non mic'ed drums. Heard new high resolution remastering "Led Zeppelin III" "Since I've been loving you" on weasayso's system, and think of that as being better one when focus on drum/symbols department.
 
Ever tried listening to: Russian Circles - Harper Lewis?
Also lots of The Doors have very cool drum tracks.
Usually drums are spread too wide in a lot of tracks, in some Rock from the 80's they are almost a thin line in the center with cymbals panned hard to the sides. Awful. Lot's of pré 80's is so much better in comparison.
A more recent band like Rival Sons records a lot like the old bands did, with more realistic staging. With a fun 'live' feel to it.

I also like the album: Into the Electric Castle from Ayreon as a whole, might not be realistic as such but very well done.
Zappa comes to mind.... again not the example of placement, but the vibe of it all is awesome.

With you being a drummer, get that lower end in check, timing wise. Try it, you might like it! It brings me closer to the raw energy music can have. More important of course is the fighting against the room to get it there. Arrays can do it.
 
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