fEARful Sub build advice

[eestatic]

Greetings. I'm looking to build a Sub to complement my 12/6/1 fEARful cab. I'd appreciate any experience/feedback from y'all that have went this route. Ok. Pro's/Cons on going with a larger speaker build or stay the same 12"?? Seems i've read somewhere about adding a 6" to the Sub setup?? What say Ye?

Gracious!!

 

[Passinwind]

Greetings. I'm looking to build a Sub to complement my 12/6/1 fEARful cab. I'd appreciate any experience/feedback from y'all that have went this route. Ok. Pro's/Cons on going with a larger speaker build or stay the same 12"?? Seems i've read somewhere about adding a 6" to the Sub setup?? What say Ye?

Gracious!!

Does your current 12/6 have the 18Sound 6 or one of the Eminence ones? If the former, go with a 12 sub and upgrade your 12/6 crossover. If the latter, another 12/6 may make more sense. This is assuming you like the tonal balance of the cab you already have, do you?

 

[CosmicRay]

I play out with Greenboy cabs.
A Fearless 212 for most gigs, and a 215 for the theaters and large halls.
I had a 15/6/1 & 15 sub, that was a monster set up.
But anyway, the man whom you should speak to is Paul from Scabby Road.
He's a Greenboy builder and has helped me on some issues.
And he's a nice guy!

he's listed on the Greenboy website....
greenboy.us speaker enclosures

However, I'm sure any of the listed builders would be able to offer advice.

Good Luck!

(imho - stay with the same speaker size.....)

 

[Pep]

If you want to build it I’d contact Leland at SpeakerHardware.com. He could recommend the way to go and has fEARful “flat packs” available. They’re precut and easy to assemble.

www.Speakerhardware.com

 

[eestatic]

Does your current 12/6 have the 18Sound 6 or one of the Eminence ones? If the former, go with a 12 sub and upgrade your 12/6 crossover. If the latter, another 12/6 may make more sense. This is assuming you like the tonal balance of the cab you already have, do you?

I enthusiastically like the tonal balance of my cab. Even though i'm a newbie w/the bass, I sure can identify good sound & I'm getting better at my playing and now am starting to tinker with the various settings on my amp head, ect. In my 12/6/1, I have the 6NM410. ....."upgrade your 12/6 crossover", are you referring to my existing 12/6/1 cab or utilizing a cross-over for a single (12)/(15) Sub??

I'm a glutton for punishment and will cut my own plywood :0
Thanks all!!

 

[singlemalt]

The fEarful 12 sub is a simple build. You’ve already got the high powered mid driver in your current cab, and that should be enough to carry both low end drivers. You might need to work on your crossover to increase the mid driver output. Does it already have a switch or adjustment for mid levels? Does it have a horn?

Post a few pictures, and let’s see what you have.

I’ve played around with the full range plus sub idea. In the end, I figured building out another full range was only marginally more expensive in components, and not much more construction time. A sub can only function as a set with your full range cab, it’s no good by itself. Two complete fEarfuls will give you more options.

Example: 12/6 cube with the inexpensive alpha 6 mid. The Alpha 6 is maybe $30. A little more carpentry than the 12 sub, but you end up with a great pair.

You could build another 12/6, mirror image of the one you have, with the alpha 6, and run the pair (at 4 ohm).

TLDR: a complete cab is not much more costly that a standalone sub.

 

[eestatic]

 

[eestatic]

So, sans the horn, the recommendations are to go w/a 12/6 with appropriate crossovers?

 

[singlemalt]

Any switches or controls on the back? That’s a great looking build.

Depends what you are shooting for….

More volume? A 12sub paired with your 12/6/1 would do that by moving more air and letting your amp run at 4 ohms. You get more watts. A sub is the simple and least expensive choice.

Your current cab has everything you need to pair with a sub. Most folks with a 12/6/1 and sub pairing had a switch to moderate the hot mid driver when running the 12/6/1 solo (an Lpad) or to let it run hotter with the sub.

I built a pair of 12/6 cubes and never took more than one to a gig. Moderate volumes with FOH support or small gigs without, one was plenty.

Want another fEarful because the build a cab itch is strong? A cab to leave at the practice space? Or just feel like crushing your band mates? Build out another stand alone cab.

The fEarful concept was that cabs would work well together with similar driver sizes. 12/6 with 12/6 or 12 sub. 15/6 with 15 sub or a pair of 15/6. Or 12/6 cubes stacked together, or 12/6 cube over a 15/6/1.
(I’ve done it, it’s overkill)

Maybe you build a 15/6 for a big/ small choice.

There are some complications….the 15/6 needs the 18 sound mid. The 12/6 can do fine with the alpha 6 mid. For all the variations there are various crossover configurations.

I had a pair of 15/6/1’s, a 15/6/1 and a sub, a 12/6 cube and finally a pair of 12/6 cubes. I like building cabs. For my money, the easy schlep, and great sound, the biggest bang for the buck was a single 12/6. The big cabs got sold. And I liked the 12/6 with the inexpensive alpha6 mid for straight up bass playing.

Remember, the fEarfuls were a full range design, meant for extended range bass or keys or whatever you wanted to throw at them. Kind of a personal PA on stage.

So, you are already where I ended up. A 12/6 to start would have done me just fine.

If you like DIY, the fEarful cabs are proven winners. Half the fun is cranking up some tunes in the shop and building, so you can’t just build one…have fun!

 

[eestatic]

Yes, i have the Lpad & horn switch on the back of my cab. I was/am tonally curious as to what a sub will bring to my set up. Can you readily hear a low freq. difference? <disregard volume> Anyways I need to make another cab to leave in the Church Choir loft as it's hyper discouraging to pack/drag/carry/grunt the cab from my upstairs man-cave to church, up the spiral staircase and reverse order the process an hour later! :0 Initially I was leaning to make an identical one (12/6/1) AND a Sub..to keep at home or whatever the future brings.

 

[Wasnex]

Yes, i have the Lpad & horn switch on the back of my cab. I was/am tonally curious as to what a sub will bring to my set up. Can you readily hear a low freq. difference? <disregard volume> Anyways I need to make another cab to leave in the Church Choir loft as it's hyper discouraging to pack/drag/carry/grunt the cab from my upstairs man-cave to church, up the spiral staircase and reverse order the process an hour later! :0 Initially I was leaning to make an identical one (12/6/1) AND a Sub..to keep at home or whatever the future brings.

I have never seen a 12/6 in person...but I believe this is what you should expect.

I believe this cab uses the 3012LF, which is not a particularly efficient driver at 95.5dB 1W/1m. Adding the second woofer should increase sensitivity by +3dB for 98.5dB 1W/1m. Impedance is cut in half and power handling doubles. If your amp doubles power with the second woofer you get +6dB.

The gain in efficiency is from mutual coupling. Optimal mutual coupling occurs for frequencies where driver spacing is within about 1/4 wavelength. In other words it happens at lower frequencies.

This is why the crossover has a switch for the mid range. My guess is the switch reduces attenuation of the mid range by about 3dB, so it better matches the combined output of both woofers.

Since you have a L-pad on the tweeter, you can also turn it up by approximately 3dB to keep the overall tonal balance the same.

With the adjustments, essentially the added woofer will allow the system to play 6dB louder, or give you 6dB more headroom, while retaining pretty much the same sound and tonal balance.

Keep in mind, that most speakers do not have the ability to rebalance the mids. So when you add a matching cab, you get the impression of more lows.

The following graphic suggests the woofer of the 12/6 is mechanically limited to 533.5W.

The RMS power rating for the 3012LF is 450W.

Calculated SPL
12/6 at 450W = 122dB
12/6 at 533.5W = 122.8dB
FYI I generally shoot for a rig that can make at least 124dB. So a single 12/6 may not meet all of my volume/headroom needs.

12/12/6 at 900W = 128dB
12/12/6 at 1067W = 128.8dB
Most likely on the volume department--that's pretty darn loud .

The SPL capabilities shown on the graphic are slightly lower than the calculated figures using the RMS rating.

I would expect real-world measured output to be a few dB lower due power compression.

Anyway, I think building the 12 Sub is well worthwhile (IMHO of course).

Good luck with the build !

 

[singlemalt]

fEARful Bass Guitar Cabs FAQ

It’s been a few years so my price memory is outdated. Prices have easily doubled since the last time I bought parts.

Plywood has also gotten expensive. I’d estimate a no frills sub build would run $350 for parts and material. Add $80 for an alpha 6, or close to $200 for the upgrade 18 sound driver.

The sub has its own coil and capacitor, basically the low frequency parts of the 12/6 crossover, and the cab is ported to produce the same low end as the 12/6.

Adding the sub, you don’t get more lows, (lower lows) which would run into mud, you get an overall bigger, louder rig. Again, the sub alone sounds terrible.

A 12/6 and sub would easily carry a room without PA support.

 

[yodedude2]

I had a 12/6 and 12sub rig at one time. If you follow the original design specs exactly, the setup gives you more of the same. But...what I would do now to combine with a 12/6/1 is make the budget 12/6 and add an L-pad to the mid on the 12/6. If you do this, remember to make it a ‘mirror image’ cab, it makes an audible difference when you run both cabs together.

 

[Passinwind]

Yes, i have the Lpad & horn switch on the back of my cab.

The mid pad switch is what I was referring to, you're good to go if you choose the 12 Sub route. I'm in agreement with pretty much all that @singlemalt posted, and even though I helped get him started down this rabbit hole, he's built a whole lot more of these things by now than I have.

 

[yodedude2]

piling on here ... my take on the 12 sub is that if gives one the option to have a modular rig, i.e., a 12/6/1 or a 1212/6/1. one needs the mid pad and the tweeter pad to make this work. seems like the o.p.'s cab has this already, so a 12sub would be the perfect modular add-on by design.

as an aside, when i was running p.a. support, i would pair a 12sub & a 12/6 to use as a f.o.h subwoofer using an outboard crossover at 125 hz. worked great!

 

[eestatic]

fEARful Bass Guitar Cabs FAQ

It’s been a few years so my price memory is outdated. Prices have easily doubled since the last time I bought parts.

Plywood has also gotten expensive. I’d estimate a no frills sub build would run $350 for parts and material. Add $80 for an alpha 6, or close to $200 for the upgrade 18 sound driver.

The sub has its own coil and capacitor, basically the low frequency parts of the 12/6 crossover, and the cab is ported to produce the same low end as the 12/6.

Adding the sub, you don’t get more lows, (lower lows) which would run into mud, you get an overall bigger, louder rig. Again, the sub alone sounds terrible.

A 12/6 and sub would easily carry a room without PA support.

Curious...i notice the crossover for 3012lf in the 12/6/1 is of different parameters than the crossover for the 3012lf in the Sub build. What is that difference for?

 

[singlemalt]

I wish I knew how the electronic stuff works. For crossovers, I just follow the plans and build it. I try to source the parts from Parts Express and avoid Earse.

Building the wood parts is more my jam.

 

[Wasnex]

Curious...i notice the crossover for 3012lf in the 12/6/1 is of different parameters than the crossover for the 3012lf in the Sub build. What is that difference for?

There are a variety of different documents, so it would be helpful if you showed the differences you are concerned about.

I downloaded the docs for the 12/6 Deluxe and the 12 Sub from Speaker Hardware. These are from the GIFs of the crossovers.

The 2nd order low pass is the same on both.

 

[Wasnex]

This is why the crossover has a switch for the mid range. My guess is the switch reduces attenuation of the mid range by about 3dB, so it better matches the combined output of both woofers.

Per the plans, the switch toggles a 6dB pad on the mid range, so the part in bold was not accurate .

Here's why: Assuming the voltage is held constant, adding the second woofer cuts the impedance in half so the power doubles (I.E each woofer draws the same amount of power). As a result you get a total of +6dB more output in the low end.

Let's start with the 95.5dB 1W/1m sensitivity rating of one 8 ohm 3012LF

The voltage for 1W at 8 ohms is about 2.83V

If you hold the voltage constant each woofer will pull 1W. The resulting impedance is 4 ohms and the total power is 2W. Each woofer is now putting out 95.5dB.

With optimal mutual coupling between the two woofers you get about +6dB from whatever level one of the woofer is making.

95.5 + 6 = 101.5dB

So you get a voltage sensitivity of 101.5dB at 2.83V/1M at 4 ohms.

Be mindful this is the same as saying 101.5dB 2W/1m, and we normally express sensitivity in terms of 1W/1m. To convert to the expected sensitivity standard, we cut the power half which results in -3dB less output

101.5 - 3 = 98.5dB 1W/1m

So adding the extra woofer does increase the systems 1W/1m sensitivity by 3dB. But in this case, it appears we need to be concerned with the voltage sensitivity of the different system components.

When you add the second woofer at 2.83V, output in the low end goes up by 6dB, but there is no change in the mids because the mid network is still working with 2.83V. In order to match the mid output to the second woofers, the 6dB pad is taken out of the circuit so the full voltage goes to the driver.

I believe the sensitivity of the mid drive is 102dB 1W/1m at 8 ohms. This is the same as 102dB 2.83V/1m at 8 ohms. So the mid driver voltage sensitivity pretty much matches the voltage sensitivity of a pair of 3012LFs which is 101.5 2.83V at 4 ohms.

 

[sclift]

Curious...i notice the crossover for 3012lf in the 12/6/1 is of different parameters than the crossover for the 3012lf in the Sub build. What is that difference for?

The CBG crossovers for the Alpha and 18Sound versions use slightly different inductor values for the 3012LF network (3.0 vs 3.3 mH). Not sure why. The difference is not very significant. The 3012LF crossover design for the sub matches the design for the 12/6 with the 18Sound mid probably because it is expected to be used with that cab.