[chrisby]

Why do only I see these things? Am I the only bore here ...

My remark was in reference to your assertion

I though this Alpair freq chart similar to the Nirvana Super12CF, it looks both use the same kind of paper for the cone.

I rather suspect the paper formulation itself is different for the two drivers in question, and honestly, as much faith as I'm known to place in the relevance of published FR graphs (particularly those tested under different conditions) in terms of the actual sound  - there are enough differences below approx 180Hz(?) and more exaggerated peaks for the AN above 2KHz to suggest that they'd certainly sound like they were "cut from different cloth"

I have heard the Alpair12P,  but not the Super12CF, so it's conjecture on my part

[driguy]

If it helps any the A12P transfer function is raw without smoothing. My pair are undergoing the break in process driven by a 18watt Scott222 tube amp. I'm listening at ~2' above as if they were headphones. I'm not hearing vocal sibilance, shout, or other nasties...yet, fingers crossed they continue to please when in a proper cabinet.

I have a pair with about 140 hours on them. They are mounted on an open baffle with no correction. I crossed over the subs at about 90Hz. I am an open baffle guy so to me putting them in a box is a waste but to each their own. The baffles are 22" wide. The driver height is important with these drivers. I made the baffles with measurements taken from my listening seat in my living room. Taking a first listen out in my garage with a taller chair yielded OK results but I added some height with some 4x4's and they really improved. They sounded uneven when the drivers were below my ears. They sound very good at or slightly above my ears. Perhaps this might be called shouty but I call it just a little rough with more peaks and valleys.
Now on to the main thing, the sound in a proper setup using nice amps and source. IMO, the sound is incredible especially considering the price. I should not even put that qualifier in there as it would lead one to believe they fall short in some way. I have Bastanis Apollo speakers which are very revealing with great extension and resolution. Those are my reference speakers. The room was just too large for these drivers (25' x 30' x 11') to put enough energy into the room with some music. That being said, the sound was very pleasing and some of the best  I have heard anywhere. If I did not have the speakers I do and such a large room I would be very happy with these. I do plan to build a pair with 4 drivers per side in the future. Yeah, they are that good. They tend to be a little more forgiving than my current setup on the high end. They may be called a little rolled off but they really are not. In a smaller room with more break-in time they may open up a little more. Very smooth but still with great extension and resolution. Very hard to get (never mind that it is a single driver!) from any speaker. Once you hear it you'll know. If you go to any of the shows, the rooms that initially wow you are not always the ones you stay in the longest. These speakers would make you just sit down, relax and listen.
I did not build a box for them so I cannot comment on what that may sound like but in an open baffle they really image like crazy. One of the reasons I purchased them is that the basket supports have a nice design that minimizes interference with the back wave. As one might expect, it is a very coherent  presentation with a great illusion of a real performance.
The cynical might say that if they are so great, why are you selling them? Well, for the reasons stated. I do not want to build a 4 per side set from different production runs.
I think the work done by Mark and his team is to be applauded. Very nice work indeed.
Regards to all,
Tony

[doorman]

Nice review! The Alpair 10.2's I currently have are very satisfying indeed. Am hoping to hear the Alpair 12's this summer (Chris/Dave?)
Thanks for posting your impressions
Don

[FullRangeMan]

Chrisby:
I noted that both drivers up and fall +- together, on the freq chart, of course the amplitude is not the same.

DRIGUY:
Thanks for your detailed report, MarkAudio always made great products.
Would I ask what woofer are you using on the OB??
What frequency are you cuting??
Thanks

[driguy]

Chrisby:
I noted that both drivers up and fall +- together, on the freq chart, of course the amplitude is not the same.

DRIGUY:
Thanks for your detailed report, MarkAudio always made great products.
Would I ask what woofer are you using on the OB??
What frequency are you cuting??
Thanks

I set the sub at about 90 which when summed gets you pretty close to 100Hz. I use GR Research open baffle servo control subs.
My amps are Emission Labs 300b XLS based with custom wound Electra-Print OPT's. Source is a 16 chip TDA1543 DAC with a 6922 output stage (not a buffer) with built in volume control.

[planet10]

Am hoping to hear the Alpair 12's this summer (Chris/Dave?)

Ours are over 1000 hrs now (stock), and we will start comparing them to other stuff soon.

dave

[planet10]

Chrisby:
I noted that both drivers up and fall +- together, on the freq chart, of course the amplitude is not the same.

Apples vrs Apples.



dave

[FullRangeMan]

Planet10:
I post the old freq chart from the Super12CF, which allow some comparison with Alpair12.
After some time David post a new datasheet from the Super12CF on the CommonSense site, that is this chart you post.
The driver is the same, but due changes in room temperature/humidity some TS and the graphic have changed.

[FullRangeMan]

I set the sub at about 90 which when summed gets you pretty close to 100Hz. I use GR Research open baffle servo control subs.
My amps are Emission Labs 300b XLS based with custom wound Electra-Print OPT's. Source is a 16 chip TDA1543 DAC with a 6922 output stage (not a buffer) with built in volume control.

Sorry, I missing you are using a sub, I though you are using a passive woofer.
Thanks

[chrisby]

Planet10:
I post the old freq chart from the Super12CF, which allow some comparison with Alpair12.
After some time David post a new datasheet from the Super12CF on the CommonSense site, that is this chart you post.
The driver is the same, but due changes in room temperature/humidity some TS and the graphic have changed.

Yes,  the black graphic that DaveD used in the above overlay (do you mean this is from an updated measure from CSA?) does look quite a bit smoother starting from the dip around 1.5(?)KHz through to 4KHz, and yet with a more pronounced hump straddling approx 8KHz.   

While the model number might be the same, are those differences enough to suggest that either the driver has been changed somewhat, or that one (or both?) of the measures might be off?  I honestly don't know, and frankly would generally say that I don't particularly care - if the final result sounds good. 

This series of exchanges was prompted by your posting graphics for both and the comment that "it looks (like) both use the same kind of paper for the cone" (which I personally doubt very much).  You might not have mend to imply it, but it could be inferred you meant that using similar paper could be deduced from looking at the graphs - which I think highly unlikely.   

[FullRangeMan]

Yes it is from a second publishing from David at CSA site.
There is many types of papers used on cones as Kraft, KSV, Hemp, banana pulp, coconut(Fostex) etc
Unfortunately the 12CF not sound good on the treble, unless with notch correction circuit, what is a heresy for a fullrange driver.

[Bob_Brines]

.... unless with notch correction circuit, what is a heresy for a fullrange driver.

Why?

Bob

[FullRangeMan]

Why?

Bob

Well, a notch filter is a xover without the inductor, it had the xover effect(eat low level energy to work and lost energy as heat). It is used to repair a poorly work done by the fullrange designer(mid and hi's in excess).

A FR with a xover yet had all the limitations from a sole driver(low power etc) and no more had the benefits(harmonic integrity, fast transients etc).
In this case is better buy a hi sensitivity two way speaker, where is possible get alot of bass, soft mid and extended treble etc

[JLM]

FR,

I'm a single driver fan too and consider crossovers evil, but what is the goal?  If it's good sound with a single driver, why not use some "help"?  Isn't the cabinet a filter of sorts?  If I use EQ instead of a baffle step is that a "no-no" too?  If I listen in a room, isn't that altering the sound?

I love the purity of single driver, but face it, there are circuits throughout the audio chain.

[FullRangeMan]

FR,

I'm a single driver fan too and consider crossovers evil, but what is the goal?  If it's good sound with a single driver, why not use some "help"?  Isn't the cabinet a filter of sorts?  If I use EQ instead of a baffle step is that a "no-no" too?  If I listen in a room, isn't that altering the sound?

I love the purity of single driver, but face it, there are circuits throughout the audio chain.

I like passive ways to adjust the sound as stuffing, round corners, paint black etc and I dont like active solutions as notch filters, eq etc to FR drivers.
I believe FR drivers had to get soft mid and treble without filters, otherwise the usual two ways(woofer+tweeter) may be better.
I said it without listening, for sure only after a good AB test.

[doorman]

Also a SD fan, but also acknowledge there's many ways to skin a cat.
Very few absolutes are absolutely true in every case--
Don

[Bob_Brines]

The reason single driver speakers sound different from multi-way speakers is phase rotation in the telephone band. Use of LR XO's exacerbate the issue. As long as the XO is outside the telephone band, the single driver sound is intact. The bulk of the phase rotation in a BSC filter is below that.

ALL "full-range" drivers have a cone break-up around 3kHz, higher for small drivers, lower for bigger drivers. The only reason that "full-range" drivers work at all is through controlled break-up. This peak is in the presence band. This is what makes many full-ranges sound "live", and it also makes them sound harsh. OK, you want that "life". That's fine, but understand that is fake.

Let's look at the purest mantra for a moment. Let's run from vinyl. We need to apply RIAA EQ to the output, but that's not really EQ, is it? Then we run it through a flea-power SET that adds a wad of even-order distortion and has a weak top. But that weak top kills the ear-bleed screaming of the rising response from the driver. Synergy, man. Synergy.

EQ is EQ. Doesn't matter where is comes from. I have yet to meet an amp/driver combination that didn't need a little help. A reasonably flat response from the amp/speaker is really what's on the recording, not a response that looks like a roller coaster.

Bob

[FullRangeMan]

BOB,
This fullrange seems absent from this peaky in the 1k - 3K range.
http://www.audiocircle.com/index.php?topic=108486.0
Do you think this freq chart is fake??

[JohnR]

This fullrange seems absent from this peaky in the 1k - 3K range.
http://www.audiocircle.com/index.php?topic=108486.0

Um, that looks to me like about 10 5 dB rise at 3 kHz.

Ha ha whoops. Can't read vertical scales! Regardless, it's still enough that you (I) would want to EQ it. The graph is very smoothed, so it's likely that in reality it's much rougher than presented.

[FullRangeMan]

Um, that looks to me like about 10 dB rise at 3 kHz.

I count 4 or 5dB only, from 92dB in 400Hz to 96 or 97dB at 3kHz.