The making of: The Two Towers (a 25 driver Full Range line array)

I like to think of it as compressed pine sawdust and glue ;)

I don't like the idea of putting a welded steel frame in a speaker :eek:

Maybe you will make me rethink when I see the end result :D

What about colored MDF/HDF like Valchromat or similar? It comes in black color as well.

The welded steel frame is a compromise. I'd rather do a cast iron frame but don't see how I could accomplish that with limited funds ;).

No MDF for me guys. Sorry :blush:
 
No MDF for me guys. Sorry :blush:

No need to be sorry, if I could get birch plywood I would use that for most things. There are some things that MDF is great for and is often dismissed as a poor material too easily. Go and ask a veneer presser if he would prefer to use MDF or plywood as a substrate ;)

Can you not get the steel place to cut the lengths smaller for you? Most have a drop saw and if you ask nicely they will just cut it for nothing.
 
I'm a bit bummed out no one seems to like my idea of using a steel frame.

Maybe I am a little crazy after all. Should that stop me from trying? If I think back how many thought I was crazy for building line arrays....

The craziness does seem to spread these days. So readers be aware! It's only fair to warn you guys. A few more days to decide what I want to do. Getting exited to start this next big experiment. Still not sure what amp to use. Only that it has to have more range than most sub plate amps and I want some kind of power reserve.
 
I'm a bit bummed out no one seems to like my idea of using a steel frame.

Maybe I am a little crazy after all. Should that stop me from trying? If I think back how many thought I was crazy for building line arrays....

The craziness does seem to spread these days. So readers be aware! It's only fair to warn you guys. A few more days to decide what I want to do. Getting exited to start this next big experiment. Still not sure what amp to use. Only that it has to have more range than most sub plate amps and I want some kind of power reserve.

Take your own advice

You are the one that can make the decision to keep yourself happy.
I'd say use whatever works best for you. Does that help? :D

If you don't think that you can achieve the same result in a more conventional way then why not give it a try. You can always take the frame out and turn it into a garden ornament if it doesn't work. ;)

Are the Hypex modules too expensive?
 
You mean the Hypex UcD modules? I haven't checked them out as I wouldn't know what I'd need. I'm not into building amps (just yet). I might be in a near future.
Some of it will be budget driven (sadly). I'd love to try the First one for the mains.

Yes the UcD modules. They are very simple a module and a power supply. You can buy a connector set from Hypex and use crimps to plug it all together. The only other thing you need is an IEC power socket audio input connectors (XLR are better) and some wire. The 400 module needs a heatsink of some kind but it can be a big aluminium plate. If you can wire a car stereo you can assemble one of these, the metalwork is the hardest part and we know you can do that :)

190 euro plus vat for a 400 module and power supply.

I can talk you through it and send you plenty of pictures of what you should be doing if you want to give it a go.

If not Behringer make some reasonable amps if you are at the cheap end of the market. A used Crown or QSC could be a good buy if they haven't been thrashed. MiniDSP have some icepower plate amps as well.
 
+1 Fluid on the ease of using Hypex UcD modules.

The modules come pre-assembled, and for a guy with your metal working skills, the chassis work will be a piece of cake... if you are feeling lazy and don't want to cut a rectangular hole for the IEC socekt, maybe you can opt for a Neutrik powerCon connector. :)
 
Yes the UcD modules. They are very simple a module and a power supply. You can buy a connector set from Hypex and use crimps to plug it all together. The only other thing you need is an IEC power socket audio input connectors (XLR are better) and some wire. The 400 module needs a heatsink of some kind but it can be a big aluminium plate. If you can wire a car stereo you can assemble one of these, the metalwork is the hardest part and we know you can do that :)

190 euro plus vat for a 400 module and power supply.

I can talk you through it and send you plenty of pictures of what you should be doing if you want to give it a go.

If not Behringer make some reasonable amps if you are at the cheap end of the market. A used Crown or QSC could be a good buy if they haven't been thrashed. MiniDSP have some icepower plate amps as well.

+1 Fluid on the ease of using Hypex UcD modules.

The modules come pre-assembled, and for a guy with your metal working skills, the chassis work will be a piece of cake... if you are feeling lazy and don't want to cut a rectangular hole for the IEC socekt, maybe you can opt for a Neutrik powerCon connector. :)

I was actually looking into buying a new Crown amp, so switching to building myself a couple of UcD based amps shouldn't be a huge setback compared to that. I could build two separate mono amps and get to choose it's form factor up to a point. Might be the way to go.

At work I'm always busy with Arduino's etc. for 3D printing so it's not like I don't have any experience with electronics, it's just not really my thing.

I still have to decide where I can hide the amp(s). Not wanting the amp to be part of the sub itself it's got to be tucked away somewhere. Plus my impedance correction circuit needs a new place to hide as well.
I'll be up to 6 channels of amplification, for stereo speakers without a crossover (well, in the more traditional sense anyway).
 
I'm a bit bummed out no one seems to like my idea of using a steel frame.

Maybe I am a little crazy after all. Should that stop me from trying? If I think back how many thought I was crazy for building line arrays....

The craziness does seem to spread these days. So readers be aware! It's only fair to warn you guys. A few more days to decide what I want to do. Getting exited to start this next big experiment. Still not sure what amp to use. Only that it has to have more range than most sub plate amps and I want some kind of power reserve.

I have been following, just not replying so much.

I do like the idea of a metal subframe very much. Weight, strength and leaves lots of place inside. I guess the reason why most subwoofer companies just use mdf is because it's much cheaper to build that way.

So, yeah, go ahead! Although we know you don't need our approval!
 
I was actually looking into buying a new Crown amp, so switching to building myself a couple of UcD based amps shouldn't be a huge setback compared to that. I could build two separate mono amps and get to choose it's form factor up to a point. Might be the way to go.

At work I'm always busy with Arduino's etc. for 3D printing so it's not like I don't have any experience with electronics, it's just not really my thing.

I still have to decide where I can hide the amp(s). Not wanting the amp to be part of the sub itself it's got to be tucked away somewhere. Plus my impedance correction circuit needs a new place to hide as well.
I'll be up to 6 channels of amplification, for stereo speakers without a crossover (well, in the more traditional sense anyway).

Modushop make some very nice aluminium enclosures and they can fit quite a few Hypex modules in. They have different sizes with more or less heatsink and come in black as well to match the rest of your gear. The chassis can be quite an expensive part but I think they are worth the cost.

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I see Power Supplys. Assumed Class D multichannel Amp. Is there DSP?

Nice and light... Sigh. I miss my toroidal transformers. But that's potential power right there.

8 channel Hypex UcD Class D. 6 x UCD 180 on the sides, 2 x UCD 400 in the centre at the rear. 2 x 1200W power supplies at the front.

I don't miss toroids at all. Every single one I own hums annoyingly in the house I live in now. If I used toroids this would weigh about 40 to 50 Kg. In lower power devices I am using R-core transformers now and they have no hum either.

DSP lives in another box. These hum too but is harder to hear because they are so small.

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This seems less off topic now that wesayso's system is gradually becoming an active multiway :)
 

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Class D used to have so much IM and THD distortion tho. Was perfect for cars, but 10% THD is not attractive for home. Have things gotten better?

Not all Class D amps are alike. Bruno Putzeys know what he is doing ;)
This is THD and IMD for UcD400 the ncore is a bit better. SL also has some IMD testing on his site and you can see that the UcD is very good in that regard.

Distortion Link to testing graphs

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DIY multichannel DSP?

Do tell us more. I've been looking around for something like the Exasound e38 but without the price tag.

It's a Najda DSP board in a box I designed with a linear power supply kit. I don't know how easy they are to get anymore as Nick the designer dropped off the map a bit. His website is still up but I haven't tried to contact him to know if they are still available.
 
It's a Najda DSP board in a box I designed with a linear power supply kit. I don't know how easy they are to get anymore as Nick the designer dropped off the map a bit. His website is still up but I haven't tried to contact him to know if they are still available.

Looks nice. But from what I read, it only takes 2-channel input and can split them into 10 channels of outputs.

Also, no mention of the AD/DA chips used.

I'd like to have something that will take either 2 channel input OR multi-channel inputs, USB or HDMI, allow me to split or apply filters to different channels and feed that into amp modules.

Looks like the MOTU 8a or 16a with their Sabre DAC are still my best bet... unfortunately, not available in my country! :(