Eminence BETA 12CX and BETA 15A's Good Combo?

Drummerboy2 · « **on:** 11 Jan 2018, 12:42 am »

Hi Everyone, I wanted some info about the Eminence Beta 12CX and Beta 15's so I came here to ask.

Ever since I helped my cousin with his speaker and I installed Eminence Beta 12CX with Dayton DT250P screw on CD's, I can't get the sound out of my head and how good they sound right off. I know break in key but I was just surprised at how good they sound.

So My Question is would the Beta 15A's (two per side) be a good match with the Beta 12CX in an Open Baffle speaker? I currently have Carver Amazing Loudspeakers Silvers but the Latino VTA-120 tube amp I built last year would have trouble with the Carvers (have a sold state amp for those) so I wanted to build a High Efficiency speaker and the Beta 12CX and Beta 15A's seem to fit the bill. I like the Spatial Audio speakers but too much $$$$ for me at this time.

Any help or pointing me in the proper direction to some info would greatly be appreciated.

FullRangeMan · « **Reply #1 on:** 11 Jan 2018, 01:45 am »

The QTS of both could be higher, do you intend use DSP?
You dont like the usual Alpha15A?
W/12 inches in the mid range you have to cut at max around 1100Hz to a tweeter.

Look this OBA15SE Alpha15A clone:
http://www.pureaudioproject.com/product/15inch-open-baffle-bass-woofers/

Drummerboy2 · « **Reply #2 on:** 11 Jan 2018, 04:39 am »

I will be using a passive xover. The OB-15SE is nice but expensive for a stamped frame speaker if that buy it now option is correct. Now if it was for the cast frames then yes, those would be worth it. I will shoot them an email. Thanks for the info.

FullRangeMan · « **Reply #3 on:** 11 Jan 2018, 06:55 pm »

Quote from: Drummerboy2 on 11 Jan 2018, 04:39 am

I will be using a passive xover. The OB-15SE is nice but expensive for a stamped frame speaker if that buy it now option is correct. Now if it was for the cast frames then yes, those would be worth it. I will shoot them an email. Thanks for the info.

Its about the same Alpha15A price, this price is per pair.
And its much better than the soft bass 15A QTS=1.26

FullRangeMan · « **Reply #4 on:** 11 Jan 2018, 07:30 pm »

In that 140-2500Hz range you would look a 10/12'' FR or Wide Range or even an coaxial driver instead a woofer.

Drummerboy2 · « **Reply #5 on:** 13 Jan 2018, 09:56 pm »

I sent Pure Audio Project an email with some questions but have yet to hear back. Hopefully this week I should hear something from them.

FullRangeMan · « **Reply #6 on:** 13 Jan 2018, 11:04 pm »

Nice to hear the news.

jparkhur · « **Reply #7 on:** 14 Jan 2018, 01:39 am »

??? 750 dollars for 4 neo s and 240 dollars for alpha 15a. I’m not sure that is close. Drummer go look st my pap build and current leftover build. Jp

Drummerboy2 · « **Reply #8 on:** 14 Jan 2018, 05:06 am »

jparkhur, where is that located so I could check it out?

The Eminence Beta 15A woofer has a QTS of .58 compared to QTS .72 of the OB-A15neo. Plus the Beta 15A's have a Fs 35Hz and Sensitivity of 98.2db 1W.

Eminence Beta 15A's X 4 = $271.96 but may only need 1 per side.

FullRangeMan · « **Reply #9 on:** 14 Jan 2018, 05:21 am »

Plus the Beta 15A's have a Fs 35Hz and Sensitivity of 98.2db 1W.
These values are is a big BR box, the Beta was made to BR or Sealed boxes, in OB it will lose 4-5dB.
Recommended for professional audio as a
woofer in sealed and vented enclosure

Drummerboy2 · « **Reply #10 on:** 14 Jan 2018, 05:28 am »

FullRangeMan, I thought the same when I saw the specs but I have seen a few post on the net where they (Beta 15A's) were used in an OB and with good results since the OP. Maybe that's why they used two per side since there was a drop off in dbs. I'm still waiting to here back from the Pure Audio Project before I make a decision on which woofer to use.

Drummerboy2 · « **Reply #11 on:** 14 Jan 2018, 05:32 am »

jparkhur, I found the post with your speaker build. Thanks

FullRangeMan · « **Reply #12 on:** 14 Jan 2018, 05:36 am »

The PAPs were designed to OB as the Alpha15A.
The Betas needs correction.

MJK · « **Reply #13 on:** 14 Jan 2018, 01:46 pm »

Why not simulate any or all of the drivers mentioned in BASTA. It is free!

http://www.tolvan.com/index.php?page=/basta/basta.php

You can compare the different drivers in an OB with an active or passive crossover to see the bass response and SPL level for each one. You can refine your design using baffle size and shape, number of woofers, and crossover frequency and slope. Use this data to help guide your design decisions before you spend any money. An afternoon of mental effort will short circuit all of the guess work/discussion and up your chances of producing a great sounding OB speaker system.

Drummerboy2 · « **Reply #14 on:** 14 Jan 2018, 07:43 pm »

MJK, Thanks for the info. I will check it out.

Drummerboy2 · « **Reply #15 on:** 15 Jan 2018, 12:38 am »

Well, I downloaded that software and saw how the Beta 15A would work in an open baffle. The Baffle was going to end up being bigger than what I wanted and I already have Carver Amazing Silver so I will juts go in another direction.

I currently have the components for a 2 or 3way horn setup using the 15" Knock Down cabs from Parts Express. I will be using the MCM 55-2963 15" woofers in place of the JBL 2235H's, I do have a pair of JBL 2123's and QSC Horns with the Dayton D250P cd's. If that doesn't work out I will get the Beyma TPL-150H heil style drivers. So far the simulations look great!

I want to say Thank You to everyone who chimed in with some good info.

FullRangeMan · « **Reply #16 on:** 15 Jan 2018, 01:43 am »

If you have the Amazing why you want other speakers?
I would suggest you stay with your Amazing its a lot of SQ even today, just keep the no toe-in and up right no tilt back position. The Amazing bass damping adjusting is great, never see other speaker with this useful device, its the master piece from Bob Carver.

MJK · « **Reply #17 on:** 15 Jan 2018, 02:05 am »

Quote from: Drummerboy2 on 15 Jan 2018, 12:38 am

Well, I downloaded that software and saw how the Beta 15A would work in an open baffle. The Baffle was going to end up being bigger than what I wanted and I already have Carver Amazing Silver so I will juts go in another direction.

Try the Alpha 15A in your simulations, the baffle can be much smaller and the bass will still be flat down below 50 Hz.

Drummerboy2 · « **Reply #18 on:** 15 Jan 2018, 02:37 am »

FullRangeMan, This speaker was going to be for my Latino VTA-120 TUBE power amp, so the speakers need to be more efficient than the Carver Amazing Silvers. If the VTA-120 could push the Amazing without any issue I wouldn't be having to make another speaker and would just be happy with Carvers for both systems. The Carver's are a really nice speaker and with some of the tweaks I did sound better than stock. I have an EDGE M8 power amp for the Carvers and it sounds nice and the bass shakes the windows! I also have the Carver Loudspeaker Control system module for them too which work nicely, the Carver Amazing Silvers can throw a very wide soundstage with this unit egaged but I prefer without. The unit also has a "Q" control for controling the "Q" of the speakers.

On placement of the Carver's, I used the Carver setup/placement user guide and the instructions are dead on correct. So I have followed and have never had a issue with sound. The bad experiences and feedback about the Carver Amazing not sounding good or bass shy is mostly due to the users not follow the Carver Amazing setup instructions. For these speakers you need to have a good size room for proper placement.

The Open Baffle project I came here for help was for the second system that has all Tube gear and power amp. So this is why I need a more efficient speaker system.

Thank You for the help, I really appreciate it.

Drummerboy2 · « **Reply #19 on:** 15 Jan 2018, 02:44 am »

MJK, Yes, I will try some more sims. I think I can get by with just one Beta 15A or Alpha 15A per side, after looking at the dbs. it would have been too much for two per side with the Beta 15A. I also used the Xover Pro software and came out with a good OB design but it will use a lot of components. The Graph was pretty good.