Custom Rig Build with Pro Audio Speakers

[Rick James]

I'm used to pulling up a .pdf that has a chart and a list of specs where I can see the "useful" frequency range, power handling, etc..

You're referring to driver data sheets, which are important, but by themselves don't tell you much. An expert can look at some of the specs, like Fs, Qes, Qts and Xmax, and make a ballpark assessment about the driver capabilities, but even an expert wouldn't dream of using that assessment alone. The only way to accurately predict the low frequency sensitivity, response, power handling and maximum output is with speaker modeling software, like WinISD 0.7.
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After you've taken a year or two to really understand it, and then built a half dozen or more experimental cabs, each better than the one before it, you might come up with something as good as what guys like greenboy and Bill Fitzmaurice have. Or not. At any rate if you're really set on designing and building your own cab the place to start is on a site dedicated to building speakers, like Invalid Link Removed

 

[onamission]

The DefinaMax is a horrible choice for bass guitar, terrible mid response, terrible sensitivity, and I would suggest about 600 watts RMS per driver long term.



No way will they hold up to 500 watts RMS each.


24dB/oct is a good compromise, Butterworth alignment.

True, but the pair will do 800w all day long though. Good inexpensive choice for a home built high power cabinet.

 

[Arjank]

No way will they hold up to 500 watts RMS each.

The Dayton PA310 ain't that bad.
Sure, it can't hold 500 watts but it can handle 400 watts from 45hz and up in a 50 liter enclosure tuned to 50hz before exceeding xmax (5mm).
IMHO a very impressive 12 for $66.75

 

[D.A.R.K.]

24dB/oct is a good compromise, Butterworth alignment.

Agreed- I just see this automatic response of "high pass" all the time, without any real specifics. The Fdeck unit is well liked, but only a 12 db per octave cut with no alignment specified. It really is going to depend on what your port tuning is, coupled with what frequencies you will be feeding the cab and the amount of power you will be using. For sub tuned instruments you may want to go as far as a 48db per octave slope around the port tuning frequency. It takes some experimentation based on the specs to get it right, especially if you are using heavy handed eq to bring forth those sub tunings.

 

[agedhorse]

True, but the pair will do 800w all day long though. Good inexpensive choice for a home built high power cabinet.

At lower sensitivity and abysmal mid response. I have a heater that will handle 1500 watts, but power handling alone does not make for a suitable or acceptable speaker for bass guitar applications.

This is a good example of why it's important to understand something before making recommendations imo.

 

[onamission]

[QUOTE="This is a good example of why it's important to understand something before making recommendations imo.[/QUOTE]

Exactly

 

[-Asdfgh-]

First time poster, been reading posts for a while:

Ultimate goal: Put together a small, powerful, all-purpose rig (Head and cabs)
However: I can't leave good enough alone. Off-the-shelf solutions always seem to have a critical drawback, the most common being not getting the 1000W (or even 800W) into a single cabinet at 4ohms. Two smaller cabinets cost twice as much, weigh more... I'm sure some of y'all have been gear shopping.

Specifically: I want about 1000W at my fingertips, and a 2x12 (or 2 12" cabs) seems to be where I'm headed, after reading about 30 threads on the topic here (possible exaggeration). I've looked at and am considering Markbass head or a Peavey MiniMega. Currently use an MXR bass DI and a EQ pedals headed straight into a QSC GX7 power amp, which I may consider sticking with.

Experience has informed me that anything short of 1000W will leave me turning all the knobs up to 11 in practice and gigs. I play a 5-string tuned to Ab, and find myself struggling to get decent projection in the low notes. The style that we play kinda demands that there is something from my corner shaking the walls a bit. I currently use 15" speakers (Eminence Kappa Pro 15A) in a few different cabs (with no consideration for enclosure size, port size, etc), but suspect that speaker size is not as important as I once thought. The idea of carrying around a pair of 12" cabs makes me almost giddy.

The trend out there seems to be to stick to speakers designed for bass guitar, to which I lend a great deal of respect. What would be the problem, if any, in reaching for something like an Eminence Definimax 4012ULF paired with a Legend BP122, with the appropriate box size and venting, and a crossover to make sure everyone is playing in their zone?

Of course there are a zillion speakers out there with which to tweak this question, with trade-offs of cost, weight, sensitivity, etc. I have all of the tools, carpentry/basic electrical skills, and patience for mistakes. Any feedback as to whether I am barking up a huge waste of time and money is greatly appreciated.

I'd think about SPL and frequency plots, not Watts. 100W can be loud, 1000W quiet depending on speaker/cabinet sensitivity and EQ.

 

[Reuptake]

Ab~26hz=fundamental/1st harmonic
52hz=2nd harmonic

I suggest trying an HPF set at about 60 hz with what ever rig you use.

Also have your guitar player(s) HPF around 120hz.

Your rig will sound better and speakers last longer.

What's a quick and dirty way of accomplishing this (HPF)? What you are saying makes total sense. What I usually do is listen to my amp during soundcheck and carve out the frequencies on my EQ pedal that make my speakers sound like they're gonna blow (the 31hz lever on my MXR). I see lots of parametric EQ pedals out there that have a high and low shelf on them... I even have a Grace channel strip that I've contemplated as a pre, but is currently used for vocals.

Also, short of threats of physical violence, how does one convince a guitar player (constantly complaining of lack of bottom end) that they need a HPF?

 

[-Asdfgh-]

Never heard of having a 1k cab not being able to move the wanted air or giving you the volume you need... I once ran 900Watt into 4 Ohm (warwick tube path 10.1 and the 900W 4 Ohm'ed 6x10 cabinet), it was loud enough to play Wacken Open Air Metalfestival without seperate FOH support. (I am not joking)
Same goes for my Ashdown 600Watt at 4Ohm setup. 600Watt at 4Ohm is stupendously loud (let alone the 900 Watt at 4 Ohm mentionned before)

Somebody made a suggestion of the EQ, I can wholeheartely subscribe to that.

It's not really 600W, as opposed to '600W at 8 ohms' or 400W as it is known. It is the SPL that counts, so really it is '600W and a whole load of speakers meaning good sensitivity'. My back says quieter is acceptable, though

 

[MDBass]

Cool, thanks. Almost right away discovered that we are certainly not limited to the "Guitar/Bass Speakers" section of the Eminence website. While wandering down the fEARful path: At the heart of my original concern, is there certain characteristics of speakers that would make them patently inappropriate for a bass guitar cabinet? The concern that comes immediately to mind is 'durability'. In my youth I would just plug stuff in sometimes, like a bass guitar into someone's poor 2x12 guitar combo, and end up destroying the speakers even though I didn't feel like I was pushing anything.

Going back to the example of the Definimax 4012ULF. There looks like a pretty steady drop-off after 200Hz, so it's use is clearly limited, but it calls itself a 1200W speaker. Could this help solve the size vs power problem?

The opposite is true.

If you destroy a Fearful via overexcursion, you're already dead (or at least deaf) from the resulting SPL

 

[MDBass]

First time poster, been reading posts for a while:

Ultimate goal: Put together a small, powerful, all-purpose rig (Head and cabs)
However: I can't leave good enough alone. Off-the-shelf solutions always seem to have a critical drawback, the most common being not getting the 1000W (or even 800W) into a single cabinet at 4ohms. Two smaller cabinets cost twice as much, weigh more... I'm sure some of y'all have been gear shopping.

Specifically: I want about 1000W at my fingertips, and a 2x12 (or 2 12" cabs) seems to be where I'm headed, after reading about 30 threads on the topic here (possible exaggeration). I've looked at and am considering Markbass head or a Peavey MiniMega. Currently use an MXR bass DI and a EQ pedals headed straight into a QSC GX7 power amp, which I may consider sticking with.

Experience has informed me that anything short of 1000W will leave me turning all the knobs up to 11 in practice and gigs. I play a 5-string tuned to Ab, and find myself struggling to get decent projection in the low notes. The style that we play kinda demands that there is something from my corner shaking the walls a bit. I currently use 15" speakers (Eminence Kappa Pro 15A) in a few different cabs (with no consideration for enclosure size, port size, etc), but suspect that speaker size is not as important as I once thought. The idea of carrying around a pair of 12" cabs makes me almost giddy.

The trend out there seems to be to stick to speakers designed for bass guitar, to which I lend a great deal of respect. What would be the problem, if any, in reaching for something like an Eminence Definimax 4012ULF paired with a Legend BP122, with the appropriate box size and venting, and a crossover to make sure everyone is playing in their zone?

Of course there are a zillion speakers out there with which to tweak this question, with trade-offs of cost, weight, sensitivity, etc. I have all of the tools, carpentry/basic electrical skills, and patience for mistakes. Any feedback as to whether I am barking up a huge waste of time and money is greatly appreciated.

Barefaced, Fearful/Greenboy or Audiokinesis will all get you what you're after.

Here's me awhile back at a loud rock gig, no PA support, and a single Barefaced 12 powered by MarkBass 500 watt head:

 

[SactoBass]

First time poster, been reading posts for a while:

Ultimate goal: Put together a small, powerful, all-purpose rig (Head and cabs)
However: I can't leave good enough alone. Off-the-shelf solutions always seem to have a critical drawback, the most common being not getting the 1000W (or even 800W) into a single cabinet at 4ohms. Two smaller cabinets cost twice as much, weigh more... I'm sure some of y'all have been gear shopping.

Specifically: I want about 1000W at my fingertips, and a 2x12 (or 2 12" cabs) seems to be where I'm headed

Hello Reuptake! Welcome to Talkbass!

Check out the Barefaced Super Twin and Big Twin 2. They will easily handle 1000 watts and say to you "pffffft......is that all ya got?"

Barefaced Bass - Product Range

 

[Reuptake]

Hello Reuptake! Welcome to Talkbass!

Check out the Barefaced Super Twin and Big Twin 2. They will easily handle 1000 watts and say to you "pffffft......is that all ya got?"

Barefaced Bass - Product Range

The Super Twin definitely checks all the boxes for me, and there seems to be a fair consensus amoung those more learned than I that the Barefaced cabs will play at least as well as the person holding the bass . The weight is significantly less than a fEARful 1212/6. Could spend less money building the fEARful, but DIY projects are ALWAYS more expensive than projected.

 

[SactoBass]

but DIY projects are ALWAYS more expensive than projected.

So true!

Btw, I just ordered a Barefaced cab. It couldn't have been easier, and the folks over there at BF are excellent to work with! Nice guys! And Alex (the designer) is one smart cookie! I trust his engineering.

For the record, I have no affiliation with BF. I'm just a customer.

Good luck in your cab search!

 

[Daniel Piper]

The greenboy audio stuff maybe?

sorry if this is a bit off topic but where do people in the states buy barefaced cabs. I’m interested in getting one of their twin cabs but it seems like theyre made overseas and have very little availability here.

Try living in New Zealand! But yeah - you order direct from them. The website has prices listed including worldwide shipping.

 

[Reuptake]

Get two Dayton PA310-8 12"s from parts express and build this:

View attachment 3101319

Very cool, simple design.
What is the port diameter and length here, and is there a partition between the two speakers?

 

[onamission]

2 - 4x4 ports, no partition

 

[onamission]

Sorry 6 3/4 length

 

[onamission]

Here's a better view plus a 1x12.

 

[Reuptake]

Sorry 6 3/4 length

Sweet, thanks!
Follow up on a speaker-spec debate here: Aside from cost (1/3 that of the Kappalite 3012LF), why the Dayton (or to a nay-sayer, why not)? My personal amateur comparison is that they are both handle 450W at 8ohms, with a similar frequency range. The Dayton is a little more efficient, has a smaller Qts (I heard that this is important somehow), and is heavier. While I promise on all that is good and decent in this world that I will start using an HPF, my main concern in a speaker is still being able to get a nice beefy bottom end without buying new speakers every week.

PS: I realise that the cab specs here are for the Daytons, and this option is seductive because is saves me about $1000 over some of the alternatives. I just can't leave good-enough alone.