New FRFR Option: £120

[Hugomack]

ride:This is my attempt to avoid having to pay large sums for FRFR while still using my splendid EVMs - so I can use the new cab sims...

EVM 12L for low end, cut-off at 1.6kHz (where they do a little dip), into a 60watt 8 ohm compression driver, complete with 'mixer' knob.

It works a treat, with another EVM for when I really need to make a LOT of noise. I'm looking forward to the next UK get-together to compare it with CLRs etc.

I'm looking at using this for the Dry of a WDW, using a Matrix GM 50 and my GT800, into two EVM loaded ported cabs. The Wets will go through the EVMs, out of Output 2 (no cab sims). This leaves outputs for FOH...

 

[pdup]

Not everyone can DIY, but from my POV the elitist frfr cab's uses from-the-shelf speaker-units and maybe cross-overs that are tweaked in some ways. But, this is a great way to make bucks - the huge amount of Axe-users in mind on this board.
I highly appreciate your efforts Hugomack.

 

[Hugomack]

Thanks Pdup. The DIY wasn't too difficult: I used standard 19mm birch ply, which is in fact slightly too thick and heavy for a horn which doesn't resonate that much, with only small surfaces. The timber yard cut the pieces to size reasonably accurately, and I used both Hard As Nails glue and screws, with thin battens to secure the front and rear - again probably not really necessary, but you know... I can't do tolex very well - I've always used blackboard paint on PAs I've made in the past. But at least the cabs match provided you don't look too closely. The horn gives the same dispersal as the speakers, so it works close up for me on a small stage. If anyone would like the speaker and crossover details, I'll post 'em. I had given Dirk at TT Cabs the specs, but he's too busy, which is a shame is it could become an earner for him.

I have some other purely pa 12" inch speakers, which i may also try in the LF cab. But it seemed to me that as the EVM sounds pretty rock and roll, then it's all doing it's job.

WIth the HF turned off, it sounds muffled - through the EVM and with no freqs above 1.6. WIth Output 1 going into the EVM cab without the cut-off, it also sounds muffled. But as you mix in the HF, the sparkle appears, and sounds to me more detailed than from Output 2 into just an EVM full freq without cab sims. NOt using the cab sims in this way is perfectly acceptable - I've been doing this for quite a while. But I think the cab sims do give it even more detail - it's like you can hear the cones working.... The way valve amps sound, but totally controllable.

BUt this is a high volume solution - it ain't hifi, and is designed to work with a band and be backline cutting through everything else (pleasurably). If it doesn't cut, then turning the knob has a drastic effect. Very good for swapping between LP and Strat.....a touch more for the LP.

WIth one EVM cab, around 4 does the trick. When I next gig a large stage and I use the second EVM, I expect it will require more. If you turn it right up, it's like a knife.

 

[pdup]

Don't worry Hugo. frfr has absolutely nothing to do with high fidelity.It has to do with rather low-end drivers extending the frequency range that guitar-speakers cant. Either the coax way where you screw-in a meager 1" compression driver to a 12" woofer and let the diapraghm act as a horn. Or placing a small constant-directivity horn-loaded driver physically infront of a woofer, making time-alignement troubles imminent unless you use digital corrections (and only sell the product with this - aka no passive version, can't be done with a passive network).

Btw., try using a wave-guide (this is not your typical horn - wike it) that has the same circumferance as your choosen woofer (12"). The overall sound-pressure and directivity will be much broader and the phycical "kick" will be much better. (Re.: The QSC line).
Thanks for your reply.

 

[pdup]

No one can duplicate the Axe, no one the Matrix amps. I can't appreciate these guys enough for their marvelous job.
But speakers is where we can dig-in, experiment, maybe do some DIY and get great result for lesser bucks.

 

[Hugomack]

Btw., try using a wave-guide (this is not your typical horn - wike it) that has the same circumferance as your choosen woofer (12"). The overall sound-pressure and directivity will be much broader and the phycical "kick" will be much better. (Re.: The QSC line).
Thanks for your reply.

Trouble is with the size of wave guide you're suggesting, having an opening the same size as the woofer, means I have to make a larger cabinet.... I was hoping that by reducing the length of the throat, would allow a smaller circumference outlet - at least vertically to reduce the vertical dispersion....

 

[pdup]

Trouble is with the size of wave guide you're suggesting, having an opening the same size as the woofer, means I have to make a larger cabinet.... I was hoping that by reducing the length of the throat, would allow a smaller circumference outlet - at least vertically to reduce the vertical dispersion....

I know - and with your set-up you probable are very close to what the guitar-world considers a frfr. But there's no free lunches if you want a dynamic, seam-less transition from a horn to a woofer. Look at all the hi-end wedges that really pushes air. Very few uses a coax-driver unless size is taken into the equation. Compromise...
But DIY regarding speakers are a great way to experiment. :encouragement:

 

[Hugomack]

A waweguide with a 12 inch lateral spread, but restricted in height would in fact give me what's required - a restricted vertical spread, focusing the HF sideway for my ears and those close to me....?

Something like this maybe?



JBL 2370A 1" Flat-Front Bi-Radial Horn 90x40 3-Bolt
The flat-front horns are designed for flush cabinet mounting or compact cluster applications. The horns provide uniform on and off axis frequency response at the rated frequencies. The small vertical mouth allows a gradual narrowing of the vertical coverage pattern with increasing frequency. This provides acoustic equalization of the frequency response of the horn in the horizontal plane and compensates for the falling power response of all compression drivers.

Dimensions: 6-7/8" H x 17-1/2" W x 6-7/8" D

 

[Hugomack]

But DIY regarding speakers are a great way to experiment. :encouragement:

By making your own cabinets, you can in fact often make things better than you buy. I made four wedges that are a lot better than their JBL =s.

Atomic seem rather coy about telling us which drivers they use in their cabs.... There's a similar lack of info on the Matrix site. 1x12 speaker cabs for £400 does however seem to me to be a lot...

What would you advise to avoid using a coax driver?

I'm also considering rehousing my big pa in smaller reflex cabs, and am tempted to do the same with my Eon 15 powered PA speakers, which I think suffer from their plastic enclosures.... (The latter is probably one step too far though...)

 

[Hugomack]

This has been suggested... mounted sideways to give lateral rather than vertical spread (the controlled polarised dispersal pattern is specifically designed so that multiple waveguides can be used together in a specific pattern and configuration for line arrays....)

£47 though... Costs are mounting... = £167

 

[Hugomack]

In fact, further research indicates that I'm probably closer to the right solution already. This JBL waveguide looks most suitable, and to my eye resembles the horn I've already installed. I couldn't post a larger pic, which does show some detailed ripples in the horn at the sides, indicating that it has been very carefully tuned. It's "optimised for home audio use"... Similar waveguides are used in cinema / theatre sound systems as well as home theatres and hifi.

http://www.parts-express.com/produc...?partnumber=300-7070&imagepath=300-7070_L.jpg

Maybe it's all in the name... "exponential horn" seems to be used along with "waveguide" like they're the same thing..? I don't think so, but there's that suspicion.

But at least these are bits of plastic that don't cost anything. Provided you don't go for a waveguide lens like the one in the previous post, cost is around £4. At that price it's worth a bit of experimentation.

 

[Hugomack]

PS - I'm enjoying doing an almost one-man discussion... Ho'ing my way to immortality. The Dutchman understands

 

[Hugomack]

Have discovered the secret of serious bass response: the Rotary Woofer, which cracks in between 1-30 Hz. So without one of these in your rig, FRFR isn't happening.



Shown here is its' cab:



A Huey Cobra's rotor blades produce 11Hz, so that patch isn't going to work without one - nor the Harley I don't suppose.

Specifications: Amplifier Requirement: 150 watts @ 8 ohms Impedance: 8 ohms 0Hz - 40Hz Frequency Response: 1Hz – 30Hz +/- 4dB Suggested Crossover: 20Hz @ 18dB/octave Sensitivity 94dB 1 watt 1 meter @10Hz Maximum Acoustic Output: >115dB between 1 and 20Hz. Distortion: Typically 3% or less between 1 and 20Hz @90dB

 

[trb]

hi all

as a low cost, but good sound quality, I bought an FR cab at Thoman for european axe users for 135 E. great buy for the price.
In parallell I'll use a spare cab I built with 19mm plywood to load it with eminence coax combo (Beta 12CX, ASD 1001, pbx2K5cx filter). Price is about 150$ and provide great results as in the Xitone for example.