Eminence Alpha 6A

[akarma 76]

May be someone will share with impressions about this driver? Or even better have some real measurements?
I need a midrange in 3way and that alpha looks good in first glance. Good sensitiveness, smooth response - especially roll-off. It seems it can be connected with 1st order. Any ideas?
Another possible candidate is Faital Pro 6FE200.

 

[Dissi]

The only independent measurement I know:

Source: Biete ein Paar Eminence Alpha-6A Mitteltöner - verkauft!, Selbstbau / DIY - HIFI-FORUM

 

[technofreak]

Hello,

Another independent measurement is available here

Here is my Alpha 6 in a three-way system, crossed over actively at ~250Hz, 4. order L-R. No low pass, tweeter (Celestion HF50) is passively crossed at ~5,5kHz 2. order. Measured in room ~1m distance 1/8 (or 1/12, can't remember that detail) octave smoothing (peak at ~7kHz is a microphone artifact):


As for sound, it's very lively yet not aggressive. Not the smoothest FR but detail and imaging is rather good.

Another candidate that looks good on paper would be Celestion TF-0818 - limited to 2,5 kHz in the upper end but plays down to 80 Hz. Some other guys build pics with measurements (alas, full system only) are here.

 

[akarma 76]

technofreak

Thanks, very interesting. It's pitty you have no single Alpha measurement.

No low pass, tweeter (Celestion HF50) is passively crossed at ~5,5kHz 2. order

Great. Any problems with off-axis? Roll-off is so smooth and no peaks at all? I want a minimal crossover and because of that was interested in Alpha 6A.

 

[technofreak]

Hi,

I can do single driver and off-axis measurements tomorrow. I did some off-axis measurements some years ago (I've had these drivers since 2008 and never felt a strong urge to replace them with something else), but they're with outdated passive crossover. I can check and see if I still have them later. IIRC, no problems off-axis at all. Roll-off is basically textbook 2. order; some break-up above 10 kHz, but it's 20 dB down.

 

[akarma 76]

I can do single driver and off-axis measurements tomorrow.

Great!

 

[Gary P]

May be someone will share with impressions about this driver? Or even better have some real measurements?
I need a midrange in 3way and that alpha looks good in first glance. Good sensitiveness, smooth response - especially roll-off. It seems it can be connected with 1st order. Any ideas?
Another possible candidate is Faital Pro 6FE200.

I don't have measurements of the 6a but do have measurements of the 6c (4 ohm version). My brother purchased a pair to use in his car. We spent an afternoon measuring and tweaking to see what we could come up with as far as resonance control goes...

They could play quite loud while staying clean had had lots of punch on the test IB.

I like the looks of the Alpha NEO version the best but have not had a chance to get a pair.

Look for "Tweaking the Alpha-6C" on my webpage

 

[Pano]

Gary, I figured you wold chime in.
You gave those Alphas a beating, didn't you?

 

[technofreak]

Hi,

Here come a metric ton of measurements both with and without tweeter. Baffle size 215x335 mm, around 7 litres vented (Fb ~95 Hz) and overstuffed (so more like leaky sealed box than real vented box), no HP filter, no bass modules. In-room; 50 cm distance for Alpha only and 80 cm for full mid-high module; 1/16 octave smoothing. The drivers are modded with felt pads on basket, as per Garys experiments No mods to the cone.

An externally hosted image should be here but it was not working when we last tested it.

An externally hosted image should be here but it was not working when we last tested it.

An externally hosted image should be here but it was not working when we last tested it.

An externally hosted image should be here but it was not working when we last tested it.

More here, including HOLMimpulse save file: https://www.dropbox.com/sh/e6vprocinlf5x7q/AABESIGN_tC17fO_EPIqpmp9a?dl=0

 

[akarma 76]

Very good, especially smooth roll-ff. I think it would be easy to connect Alpha 6A with tweeter. But I'm not shure what the best Low Pass xover point for it. Or without it at all?

 

[technofreak]

I guess 5 kHz 1st order would be a good starting point. That'll give you 3rd order acoustical. Or 2,5 kHz 2nd order if you want to use a wide dispersion tweeter (dome, ribbon or slot). No LP can work well, too, as in my case - it's almost perfect 2nd order acoustical roll-off. A slight widening of dispersion from 5 to 6 kHz isn't much of a problem (I guess this is where the dust cap makes sound).

(Damn pictures aren't showing up again. Oh, well.)

 

[akarma 76]

Thanks again. Really valuable information.

 

[swann]

Hi Folks,


i know its a very long time ago, but still i could'nt find any other measurements than the one posted on the german board.

I even did wrote this guy if he had made any degree measurements or checked some tsp before selling them but no awnser yet.
So i was wandering if anybody here had made some reliable stuff with that driver and would like to share it .


Greets Swany.

 

[weltersys]

So i was wandering if anybody here had made some reliable stuff with that driver and would like to share it .

Swany,

The Eminence Alpha 6 measurements below were taken in 2011, not positive if they had the "A" designation.
Sealed box of around 480 cubic inches, outdoors, approximately 5 foot off the ground, on axis, and 10, 20, 30, 40, and 50 degrees off axis.
There is no smoothing in the measurement.

Art

 

[swann]

Thanks for the Measuerements Art! Helps.... I hoped beaming would start around 3 khz and it does. So ok have to build a cabinet probe to look what thd would look like around this two breaks at 2 and 3 khz. But until than i am positively optimistic that i can cross the alpha in this area.
Have to see .


Greets Swany.

 

[technofreak]

Swany,

The Eminence Alpha 6 measurements below were taken in 2011, not positive if they had the "A" designation.
Sealed box of around 480 cubic inches, outdoors, approximately 5 foot off the ground, on axis, and 10, 20, 30, 40, and 50 degrees off axis.
There is no smoothing in the measurement.

Art

Something looks off with these measurements, too much hash for properly gated outdoor measurement and that depression in the 1 to 4 kHz region doesn't look right at all. My Alpha 6 measure much smoother, even in-room. The below measurement is with tweeter crossed at ~5 kHz.

 

[swann]

@ Technofreak,


why did you cross the alpha this high? Beam would already starting at 3-3,5 khz. What kind of tweeter do you use?


Greets Swany.

 

[weltersys]

Something looks off with these measurements, too much hash for properly gated outdoor measurement and that depression in the 1 to 4 kHz region doesn't look right at all. My Alpha 6 measure much smoother, even in-room. The below measurement is with tweeter crossed at ~5 kHz.

Neither of our measured responses look very similar to the curve on the Eminence Alpha 6A spec sheet ;^).

Your drivers may be a completely different production run, are they "6" or "6A"?

Yours were measured with a tweeter (and presumably some crossover), really apples to oranges anyway.

As far as "hash", seems high resolution Smaart (1.5 Hz) measurements show a bit more, even when smoothed.

Art

 

[technofreak]

Neither of our measured responses look very similar to the curve on the Eminence Alpha 6A spec sheet ;^).

Your drivers may be a completely different production run, are they "6" or "6A"?

Yours were measured with a tweeter (and presumably some crossover), really apples to oranges anyway.

As far as "hash", seems high resolution Smaart (1.5 Hz) measurements show a bit more, even when smoothed.

Art

6A, I bought them in 2008, I think. I used these crossoverless, really more like wideband + supertweeter style than "normal" 2-way. I have to dig around in my old files, there should be some measurements without tweeter.

why did you cross the alpha this high? Beam would already starting at 3-3,5 khz. What kind of tweeter do you use?

I used Celestion HF 50 which is a narrow dispersion bullet tweeter (around 60 degrees conical), so that this high crossover point worked quite well. These were my old speakers back from when I was a poor student, and I was coming from 8" full range drivers. I wanted similar sound to the fullrange drivers, but with smoother mids, deeper bass and cleaner highs - mid driver that could cover from 300 to 5000 Hz and minimalist crossovers were the design points.

I also attached a measurement from some German site which name I've long forgotten.

 

[swann]

Its from there: Eminence Alpha-6A | Jobst-Audioshop


He's known for nice DIY-Building Speakers in Germany. Makes his own measurements too, strange that i did not find any of this before :-D.
Here is the speaker he mentioned, a small dual 6 inch with the baby bms crossed around 2 khz JL-sat26 (LMT-261) - PA Topteil fur Kleinbeschallung | Jobst-Audio - Tontechnik
Maybe i should write him and aks if he's got any off-axis measurements....that i can post here as well...:-D.


Swany.