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my personal FRFR solution for Helix, Bass, Guitar and Party ;)

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as the project is finished, i'd like to present my personal idea how an guitarists Helix-FRFR-System should be:


Til now, i used a rather cheap 12/1 Coaxial Monitor The Box Promon 12. The sound was quite OK but not great, i had to crawl under the desk to switch it on or off and ist really hasn't the used appearence of a good oldfashioned guitar amp ;). OK, it's light (16 kg for a active 12/1).


So i wanted to have it lighter, yet more powerful, stereo, main switches at the front and suitable for guitar, bass and party.

I found some inspiration at barfaced (great site!) and in the talkbass forum.


So i decided for a a pair coaxial 12"/1 speakers as i often use the cab in small distances.I chosed the brand new FaitalPro 12HX230 for it's great omnidirectional characteristics, relativly light weight (5,12 kg), a bit more than usual displacement (more bass) and reasonable price.

The amplification is done by a Hypex PSC 2.400D module in each amp, providing a powerful DSP, 500W RMS (real power, nor marketing wattage) on two channels, resonable price and light weight (1.1 kg). Each cab has a net volume of 50 l and a separate compartment for the amp. Each amp is 50x45x35 cm, weight all together mwith speaker, amp, cables, handle, corners..... about 11 kg. :D (and rigid as a rock)


Building the baffles was a bit pain in the lollipop, as i decidet not for wood but an ultralight yet rigid sandwich of carbon fiber and XPS foam. So first, i had to manufacture the raw material, by laminating a special 15 mm XPS sheet (3D-Core with a integrated hexagonal structure wich takes resin during lamination to improve stability of the sandwich) one sided with 300 gr/m² quadraxial carbon fibre (higher strengt than usual woven carbon).


Done this, the elements were cutted


and glued to a buidsing similat to a loudspeaker


The outer carbon laminate was done afzter in one piece to get r real monocoque design


and after some other works, the toxic twins were ready to play


(By the way: These two monsters together weight less than my DT25. And they can louder. And they can Bass - a lot of bass ;)

And they can acoutic guitar, and vocals and.......)


No - not ready: I still spent some days for the dsp setup to get these little monsters sound about like good studio monitors but muuuuuch louder :D

I've some experience in designing HiFi speakers and with digital crossovers, but these driveres are different beasts and made me a hard time 'til i was satisfied.


At the moment, they just play Def Leppard right in front of me and they sound great, but it took me hundreds of measurements  in different distances and different angles and dozens of hours to get the sound i wanted. Now i understand, why so called FRFR speakers, even the expensive ones, are so different. In HiFi, you can realize real flat frequency responses even in different angles, with pro audio, it's nearly impossible as there are to many physical differences. An example: In HiFi use, you normally would'nt use a 12" midrage in a 2way speaker as it starts to focus the frequencies still al 1000 Hz.

Anyway - compared to the ProMon monitor, there is night and day. Not only from max. level, but even response, less distortion and a way better time-behaviour make a huge difference in listening. It does not matter if i play Flac or guitar, this is just another world. Til tody, in wonderes about a lot of patches wich sounded not really different. Today, i can hear the reason for these patches the first time.


But now it's done and i'm really happy and satisfied. Having a single one of them will be enough for a guitar even in a loud band. But two of them are better when it comes to stereo. Just tried some Brian May'ish stereo delay scales - just WOW :wub:

Even for a Bass, normally one piece should be enough, but with two, i'll blow the drummer away :ph34r:

For Party, i made a special setup with still deeper bass but therefore a bit less maximum level. Works even great.


So if you don't find a speaker wich match your needs or taste: Just build your own one! Baffles can  be build easier with polplar playwood. A bit more heavy but still light.  As speaker, the Eminence Beta12CX  + ASD:1001 is not as good as the Faital overall imho but really cheap and worth every cent. With a good baffle and amp, you can build your amp wich will outperform most industrial products at a reasonable price. And - it's uniqie :wub:

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Wow, very cool.


So how much do you charge for these ;)

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Hi Zooey,


thanks :)


What do you mean?


Faital 12HX230: 256.- €/pc if you buy a pair of them. I ordered in France, as the driver is brandnew and not listed yet in any shop in Germany.

Hypex PSC 2.400D: 339 €

XPS: 10.- € (if you don't take the 3D core wich is still prototype and not available - i got a pre-production sample ;) )

Carbon + Epoxi: Hard to say - about 150 € per baffle

Corners, Grip, reflex tube, cables, switch..... about 50 €

Cups, stirs, brushes, foil.....about 40 €

So all together about 845.- € piece + a lot of blood, sweat and tears if you do it the first time.


If you replace the Faital by the Emi Beta12CX and the Carbon-XPS Sandwich by poplar multiplex 12mm + heavy bracings, i think it would be about 500.- € but about 2 kg more (wich means about 13 kg and still much lighter as the ligtest speaker on the market in this class) and not as good in different directions. But still a great speaker wich will outperform most of the speakers on the market.


My construction is a bit extreme and crazy  as i planned to build below 10 kg. With wood: No chance! Since April 2017, the Faital was anounced 4,3 kg. Now, as the first speakers are on the marked, it's really 5,1 kg. :angry: Now, after i gave them a hint, they corrected the datasheet.  :unsure:

I already think about rebuilding the speakers motor with neodym  to reach my target. ;) But it's not easy to work on a speaker motor wich is already magnetized without damaging the voicecoil.


So if not any gramm counts, i would propose the poplar multiplex wich is cheaper and way easier to handle than the carbon sandwich, but i would propose a bit more bracing than i use in the carbon version. The Eminence Beta12CX + ASD:1001 is together 4,5 kg. wich will safe a part of the weight you gained with the multiplex.


One of the huge advantages is the Amp module, as you can (have to) programm the filters and EQs as you like. You can store 4 complete presets in the module. So you're not attached to 2 or three presets the manufacturer made and wich wopn't work in all circumstances. But you have to do it by yourself means also, that you should have the possibility to measure and that you have to know a bit about how speakers work. It would be not a god idea, to shoot the tweeter with 50 Hz at full level cause you forgot the highpass ;)

For the moment i like also the digital link, even if experienced people here advice to use XLR or asymetric line cables. With the AES/EBU solution i only need one cable from the Helix to one speaker and another cable to link the second speaker to the first. I also win a bit less noise, as there are one DA (Helix) and one AD (Speaker) conversion less.

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Hi mikisb, it was a joke, kind of, I just want one. Or two really ;)


It's not that I actually expect you to be starting full commercial production of these, but it'd be a great product that I bet a lot of guitarists would be interested in.


Great work!

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Hi Zooey,


ok - i misunderstood :D

I really don't plan to build and sell them - to much work and sanding carbon fiber every day probably is'nt healthy :ph34r:

And there is (of course) a downside even on this medal:

Even if the Carbon sandwich structure is enormously stiff and rigid comparing weight and size (just 1,5 cm walls),

i guess the materiel is fragile when it comes to bumps on lace corners . So it's to handle with care and not to throw around on stages.

So it's more for the "self maker" ans "self user" wich takes care of his baby ;)

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I understand, good luck with them, they seem great outside of that possible fragility.

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