Assembling Eminence Beta 12CX

[Tommy Tequila]

Greetings!

I had ordered a couple of Eminence Beta 12CX, x-overs and ASD tweeters a little while ago and finally found some time to put them together. This thread will cover the basics of getting them assembled and installed...

I have some spare cabinets lying around and wanted to compare how the Betas would sound in the two form factors.

Cab 1: Parts Express/Dayton Audio floor monitor format.
Cab 2: Crate 1x12 guitar cab, open back, a bit oversized.

Each of those cabs cost me $99, each Beta combination of woofer, x-over and tweeter was $150 (from Parts Express), so we're looking at about $250 total per cab. Not too scary.

The speakers all came packed well, and I liked that Eminence was careful to seal the back of the woofer and double seal the throat of the horn. Nothing ruins your day faster than getting a bit of gunk (or worse, a bit of metal) in the voice coil gaps. That'll gum up or saw through the insulation and voice coil wires quicker than you can say "What the ##&@)(!&!*&!!".

More in a bit.

TT

 

[scottburrow]

Cool Tommy, I'm glad that you are finally getting to your project.

 

[why360]

Cool, excited to see more. Thanks!
And well done not forgetting the refreshments. : )

 

[Tommy Tequila]

Moving along...

Assembling the woofer and horn driver is simple -- take off the protective coverings and simply screw the driver into the threaded hole in the back of the woofer. Finger tight is sufficient. The horn for the tweeter driver is already built into the center of the woofer (coaxial, dude!).

Basic tool list (other than the Sierra Nevada or libation of choice) is some wires, pliers, something to cut and strip wire with, a screwdriver, 4 or 8 screws per woofer, 4 screws per x-over. I used #8 wood screws for all the above, except the Crate cab which had built-in bolts/nuts. Note that the crossover and woofer use standard spade lugs on both ends, but the tweeter requires bare wires on the tweet end. I had some wires lying around from a past life when I ran a speaker business, so I was good to go. See the closeup of the crossover for the connections. IN for wires from the jack on the back of the cab, W for woofer, T for tweeter. Watch out that they swapped the +/- orientation from the IN to the woofer/tweeter connections.

If you don't have spade lugs, they can be picked up cheaply just about anywhere that has electrical/electronic supplies. Just strip the wire and clamp them on with a pair of pliers. I highly recommend using them rather than soldering the connections.

After my helpers had approved the woofer/tweeter assembly, I mounted the wires on the crossover and then screwed it into the back of the cabinet. Brace the Beta on the cab, hook up the wires (- is black, + is color). Drop (well, gently insert) the Beta into the cab, being careful not to let your wires be touching the back of the cone, or you'll get rattle city. Not that there's anything wrong with that, but I prefer to avoid it.

Screw the speaker into the baffle. Best is to do the screws in opposition (left side/right side/top/bottom) rather than cranking them in one at a time. If the baffle isn't flat or you overdo it, sometimes you can distort the woofer basket (frame) and then once again, undesirable things happen.

 

[Tommy Tequila]

Assemblage complete, and inspected/approved by another of my helpers!

A quick plug in confirmed I hadn't screwed anything up. More extensive listening and comparisons over the next couple days, but on first blush these are fine sounding speakers -- woohoo!

TT

 

[TroyL]

What is the part number for the crossover you used?

 

[Tommy Tequila]

What is the part number for the crossover you used?

It's the Eminence PXB2-2k5cx. That's the one they recommend for the Beta-12cx and ASD-1001 combination. From what I understand it pads down the high-end a bit to get better balance.

TT

 

[Thomas-Hawk]

... From what I understand it pads down the high-end a bit to get better balance.

TT

That is correct. -3dB, I believe.

Glad to see you finally getting the chance to work on these!

I'll be very interested to hear your thoughts, especially about the semi-open back cab, as that's what I tried my Beta-12LTA in. A semi-open back 2x12.

 

[Alainarose]

I am very interested myself as I have been on the fence about putting the same arrangement in a standard 4x12 cabinet. Been on the fence for a few months now. Just want to know how these are with the amp sims on.

 

[TroyL]

That is correct. -3dB, I believe.

Glad to see you finally getting the chance to work on these!

I'll be very interested to hear your thoughts, especially about the semi-open back cab, as that's what I tried my Beta-12LTA in. A semi-open back 2x12.

Well, this is interesting.

I started a thread today about using open back cabs for frfr and the general consensus was NO.

But here we are someone doing exactly what I was talking about. Are you using it with the cab and mic sims on in the axe?

Please let us know how it goes!

 

[Thomas-Hawk]

Well, this is interesting.

I started a thread today about using open back cabs for frfr and the general consensus was NO.

But here we are someone doing exactly what I was talking about. Are you using it with the cab and mic sims on in the axe?

Please let us know how it goes!

For my testing, I used my Avatar Vintage 2x12 over-sized semi-open back cabinet. I used one Beta-12LTA, and kept a Vintage 30 in the cab to do some comparisons with. It's a stereo cab, so I was able to run separate channels to each speaker. I use a Matrix GT800FX power amp, so I just turned down the channel I wasn't trying to hear. For the Beta-12LTA, I turned on cab sims; for the Vintage 30, I turned off cab sims. For both, I used power amp sims ON in the Axe.

Initially, I liked the sounds I was getting from the Beta-12LTA with cab sims ON. There was more low end than my Vintage 30 without cab sims, but it didn't sound like it was too much. Then I put the other Beta 12-LTA I had in there, and pulled the Vintage 30 out. Wow, was the bass response exaggerated. Way too much, with just about any cab sim I used. I also noticed that the highs weren't as crisp using cab sims as my Vintage 30 was without cab sims. However, the Beta-12LTA without cab sims had more highs than the Vintage 30 did. This basically told me that the Beta-12LTA probably does much better in a sealed and correctly sized enclosure. Which is really what it was designed for. But, hey... I had to give it a try!

So, given all of this, I've decided to go with a properly sized/tuned 1x12 wedge from Mick with XiTone Cabs! And I'm going to use the Beta-12CX/ASD-1001 combo instead of the Beta-12LTA for the higher frequency response, as I may also want to use it for just pumping music through it, etc.

Interested to hear if TT has the same experience I had with the excessive bass response in the semi open back cab.

 

[tgorycki]

Tommy, thanks for posting your progress! Looking forward to hearing any additional remarks you may have about the comparison and break-in. Looks like the 4 legged inspectors did a good job!

 

[Tommy Tequila]

@TroyL -- Yeah, I chimed in a bit on the open back thread.

My initial impressions at low volume was that there wasn't a whole lot of difference, but I'm planning on doing some more testing/comparisons this weekend. Then again, keep in mind that the ported monitor cab I dropped it in has not been tuned for these speakers yet.

I'll see about maybe doing some recording as well between my various systems.

TT

 

[jmp220478]

@TroyL -- Yeah, I chimed in a bit on the open back thread.

My initial impressions at low volume was that there wasn't a whole lot of difference, but I'm planning on doing some more testing/comparisons this weekend. Then again, keep in mind that the ported monitor cab I dropped it in has not been tuned for these speakers yet.

I'll see about maybe doing some recording as well between my various systems.

TT

Any further updates on this Tommy - be really interested to see where this finished

 

[trb]

HI thomas-hawk,

i m very interested in using one my spair cab for FRFR with beta12 combo, and your experience in great.
What is the status today with your cabs ?

 

[Thomas-Hawk]

Hi trb,

For FRFR, I have a XiTone 1x12 passive wedge, using the Beta-12CX/ASD-1001 combo. My Avatar 2x12 cab is strictly used as a guitar cab, with guitar speakers. I'm currently running Celestion Heritage Greenbacks in it.

What size is your spare cab?

 

[trb]

Hi Thomas,

my spare cab is 47x42 cm front and 34 cm depth.
sounds ok or not, for a FRFR with BETA 12 cx combo, from your experience ?
thanks

 

[fenderbender]

I built a 2x12 like this a while ago. It is awesome for the money!
Highly recommended!

 

[trb]

you mean for FRFR usage ?

 

[Thomas-Hawk]

Hi Thomas,

my spare cab is 47x42 cm front and 34 cm depth.
sounds ok or not, for a FRFR with BETA 12 cx combo, from your experience ?
thanks

trb, I meant is it a 1x12 or a 2x12? Based upon your dimensions, I would assume it's a 1x12.

I think it could work well... you might need to tune the cabinet a bit on the low end. If you get some "boominess" try adding some dampening material in the cab.