[Chops]

So after a couple of years, I think I'm going to finally be able to build my OB's which will be using the 12" Eminence N2012 woofers (four of them naturally) and a pair of MarkAudio Alpair 10.2's.

When I originally ordered the woofers from Danny two years ago, I also ordered the SA-1 amps to power them. However, a short while after getting them, I ended up having to sell the amps and woofers to fund more important issues at the time (the woofers never sold). These amps were perfect as they had the "transform circuit" built into them to compensate for the baffle/driver roll-off.

I'll be using an AudioSource Amp 100 amp to power the Eminence woofers, my Monarchy Audio SM-70 Pro to power the Alpairs, and I'll have to purchase an active crossover which is no biggie, however...

Now my question is this, can I achieve similar results to the transform circuit with just using my 31 band Behringer EQ?


Honestly, I'd rather not have to run all this extra gear (another amp, a crossover and an EQ), but if I'm to build these speakers, I need to bi-amp them, and this is the only way to do it unfortunately.

As always, many thanks in advance! 

[Jonathon Janusz]

I know the thread is old, but it doesn't say sold:

http://www.audiocircle.com/index.php?topic=114582.msg1196115#msg1196115

This AC member might have a pair of SA-1 amps for you?

Hope this helps. 

[Chops]

I know the thread is old, but it doesn't say sold:

http://www.audiocircle.com/index.php?topic=114582.msg1196115#msg1196115

This AC member might have a pair of SA-1 amps for you?

Hope this helps. 

Thanks for the heads-up! I just shot him a PM. I hope he still has them. That would make things much easier, though I really didn't want to  spend another $250 on this project. We'll see.

With that said, I'm still open to other options/opinions on my original question, or if a totally passive design is possible.

[Chops]

Well, I haven't heard anything back about those SA-1 amps, so I guess I'm back to square one.

I would still like to know if I can use an EQ to similar effects to the transform circuit. OR, if there's some way of running a completely passive system with just one amp. Even if I have to go with something like the Eminence 12" Beta 12-LTA.

[Chops]

Actually, a better option would be the Audio Nirvana Super 12's.

[Danny Richie]

These little amps don't have a transform circuit but they do have a boost circuit that will work out pretty will with those woofers. And they are cheap.

http://www.parts-express.com/pe/showdetl.cfm?partnumber=301-506

I also still have some of the 8" P-Audio drivers left in stock if you want to build out a pair of the V-2's.

[Chops]

Hello Dannie!

I just replied to your PM, and threw in a couple questions. 

[Chops]

I'm going to be going in a slightly different direction with this project and am posting in the OB forum. I'm going to sell the 12" drivers as well as the Alpair's and use my old Pyle Pro 15's and a pair of 15" top-end drivers...

http://www.audiocircle.com/index.php?topic=117806.0

[Danny Richie]

Just so you know what you are up against as you head that direction. I have looked at the 12" version of both of those drivers that you mention in that other thread. They both measure better than their 15" counterparts. But both are REALLY rough.

Here is the 12" full range driver.



It needed an 8 part passive network to straighten it out and it still sounded bad. And of coarse the off axis response is horrible. The 15 incher is even worse. The other problem I noted with the full range driver was a lot of stored energy, break up, and ringing.

Here is the 12" coaxial of the brand you mentioned. It is the purple line. The green line above it is our V-1 coaxial. This measurement (purple line) is with their stock crossover. Their crossover is designed based on electrical parameters and has not been designed by acoustic output. The result is quite clear.



Here is the measured response of our V-2 using the 8" P-Audio coaxial driver. This is the response with and without a little foam in the throat of the high frequency driver.



Get the picture?

[Chops]

Hi Dannie,

Did you ever compare the Hawthorne coaxial's, either the 10 or 15?

The reason I ask is because of price. I'd love to have a pair of the PAudio 8's, but they're a little too "up there" for me, unless I can get some stuff to sell, which I haven't been successful at yet.

[Danny Richie]

Networks for all of those units were designed based on electrical parameters. So the response across the board is very similar.



Phase relationships weren't really taken into account as you can see by the response.

Sometimes you get what you pay for.

I wish you were a little closer. I might swap you out for that pair of X-Statik's. 

[Chops]

Networks for all of those units were designed based on electrical parameters. So the response across the board is very similar.

Phase relationships weren't really taken into account as you can see by the response.

Sometimes you get what you pay for.

I wish you were a little closer. I might swap you out for that pair of X-Statik's.

Well that sucks, and really puts a crimp on things.

Yeah, I wish I was closer too. Then again, I'd probably want to be over all the time checking out everything and bugging you.

[Danny Richie]

Well you could always order the crossover parts for the V-2's one month and the drivers the next month. You'll spend a little time building out the crossovers anyway.

You can see them here: http://www.audiocircle.com/index.php?topic=83325.0   I used the V-2 crossover assembly as an example of how to assemble a crossover.

These are the parts I quoted you as well. The drivers are $175 a piece.

[Chops]

Well since I've been jonesing for some OB's, I decided to swap out the NHT's for the X-Statik's. But, before I could do that, I had to fix one of the binding posts on one of them as it had worked lose. First time these speakers have ever been opened. And man, there's nearly no slack at all on the leads going to the crossover (which is a mighty impressive network, well constructed with good quality components).








And here they are in all their glory...

[PDR]

Man, those are such a good lookin piece of open baffle goodness.

I gotta make me a pair...

[Danny Richie]

Yep, the crossover parts on those are pretty good. There are even some Gen.2 Sonicaps by-passing the poly caps in the tweeter circuit.

They can also be upgraded with Sonicaps in several areas. I had some extra space left on the board to accommodate the larger Sonicaps. Mills resistors drop right in too.



Try pulling them out another two feet from the wall and see how they sound. I know, you don't want to leave them out there that far. But just for a little while to give them a listen.

[Chops]

Man, those are such a good lookin piece of open baffle goodness.

I gotta make me a pair...

Aren't they?!

And I gotta say, these X-Statik's totally and completely blow the diapers right off of the NHT's! No joke! Let me explain...

I know this is going off topic and is not supposed to be a review or comparison, but...

First off, the NHT's have amazingly good, low bass output down to and probably below 20Hz in my room. I love bass (though I wouldn't consider myself a "bass-head"), and these give it to you without thinking about it.

With that said, that's the ONLY thing where the X-Statik's fall a little short. In normal, everyday music, you'll never know they are lacking anything in the bass department. In fact, the X-Statik's bass is faster and more energetic. They have plenty of bass weight. It's just that they're agile and light on their feet. Very detailed and tuneful. Actually, the entire sound coming from the X-Statik is more energetic, more agile, more involving, more spacious, more natural. They make the whole room come to life with energy and music.

The NHT's are very direct, meaning the sound is only coming from the space that they occupy. The X-Statik's on the other hand seem to emit sound 10 feet wide for each speaker. Together, they create a huge wall of sound spanning well beyond the width of the room. They also project the sound stage well beyond the rear wall as well as out into the middle of the room.

The NHT's are locked in a small boxed in area and seem to be stuffed in there tight, unlike the X-Statik's which are open and free to roam.

I'm afraid to move them now as they seem to be in the most perfect locations in the room. They have literally become one with the music and the room. They have never sounded this good before, even when I lived in a house with a slightly bigger room. Now I'm really torn on what to do... If anything!


On that note, I think my Simaudio transport just took a dump. 

[Danny Richie]

Maybe you just need a little room treatment and one of our servo subs to nail down the bottom end.

[Tyson]

OB's really do best when pulled out about 4 feet from the rear wall (measured from the top baffle).  You could always mark off where they are with some tape on the floor so you can put them back in the exact same spot if you don't like it.

[Chops]

Yep, the crossover parts on those are pretty good. There are even some Gen.2 Sonicaps by-passing the poly caps in the tweeter circuit.

They can also be upgraded with Sonicaps in several areas. I had some extra space left on the board to accommodate the larger Sonicaps. Mills resistors drop right in too.

Try pulling them out another two feet from the wall and see how they sound. I know, you don't want to leave them out there that far. But just for a little while to give them a listen.

I think you and I spoke about component upgrades a long time ago for these speakers. What kind of improvements can be expected?

I also noticed some new drivers on your site, the M165NQ series. Are those compatible with the current crossovers or would an entire rework be needed? What do they bring to the table that the X-Statik's drivers don't?