Apogee Duetta Signature Crossover

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Latest measurements with PEQ centr.freq 7KHz, gain -6dB, Q=06, actually very close to previous Q=0,8.

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NQoawuK.jpg
 
Latest measurements with PEQ centr.freq 7KHz, gain -6dB, Q=06, actually very close to previous Q=0,8.

Imgur: The magic of the Internet
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NQoawuK.jpg


Ah excellent your getting close. The 1/2 db thing I mention is really only valid in the mids and treb. Especially in the balance between the mids and treb. Super critical to getting a shockingly believable voice and an area that is easily missed.

With these designs what I have found is that your curve you have now will sound good BUT will lack just a touch of "air" and clarity.The blue line will sound both treeble hot AND treeble weak at same time. It may sound too polite on one recording then sound to forward on the next. I have found that its best to have the response close to the shape and down tilt that you have ( red and green) but with just a little higher output at 10 khz. Looks like your down about 4-5 db at 10k with respect to the region between 1-3 khz. I would make it more like 2-3 db down at 10k and then play with that 10k level in 1/2 db increments.

Also that slight hump around 5khz ( typical problem area for ribbons of this type of construction) may seem like no biggie BUT it can be a bit anoying in extended listen. Often the FR will look ok here BUT the CSD will show some storage here. Might want to play that down just a bit.
Actally Damic are you using DSP to taylor or are you doing it passive ?
 
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Hi lowmass,

I am doing all active, as mentioned earlier, use two Electro Voice Dx34a (digital dsp and crossover inside).

regards,

ok that makes it easyer. yea I would play with the rake down to 10k. try rake of about -3db from 2k to 10k and then play with that.

Then I goto overall level of MRT with respect to bass panel. Play with that up and down

Back and forth till ya get it. These two areas I find to be the most important
 
Came across this old thread I had started and wanted to make some comments:
I still have the Duetta II's. I did not change the crossover. Recently I tried some room correction using Dirac Live which made a difference in correcting some room flaws.

Recently I installed an electronic crossover, a Marchand XM66. For those not familiar this is a 2 way crossover at 24 db slope and variable frequency. The output goes to a solid state amplifier, for the bass panels, and a tube amplifier for the MRT's. Previously both had been on the solid state amp. I set the crossover at around 500 Hz initially and then gradually went to 440 Hz. This change to an electronic XO was by far the best 'tweak' I have done to any speaker. It especially changed the bass to have more impact. Mid range opened up but, the highs lack some sizzle so I'll be experimenting with that.
For anyone considering going to an electronic crossover for their Apogees I would highly recommend it.
 
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Came across this old thread I had started and wanted to make some comments:
I still have the Duetta II's. I did not change the crossover. Recently I tried some room correction using Dirac Live which made a difference in correcting some room flaws.

Recently I installed an electronic crossover, a Marchand XM66. For those not familiar this is a 2 way crossover at 24 db slope and variable frequency. The output goes to a solid state amplifier, for the bass panels, and a tube amplifier for the MRT's. Previously both had been on the solid state amp. I set the crossover at around 500 Hz initially and then gradually went to 440 Hz. This change to an electronic XO was by far the best 'tweak' I have done to any speaker. It especially changed the bass to have more impact. Mid range opened up but, the highs lack some sizzle so I'll be experimenting with that.
For anyone considering going to an electronic crossover for their Apogees I would highly recommend it.

The stock crossover is a 2nd-order electrical design and the XM-66 is a 4th-order electrical design. This would necessitate a change in polarity of the MRT relative to the woofer. Did you do that?

Dave.
 
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Hi Dave,
I thought I remembered the stock XO was 4th order so I didn't invert it. I will give that a try and see what changes. It should be as simple as changing the inputs to the MRT amp or the output from the amp to the MRT, right?
Thanks,
Bill

No, the stock crossover was definitely not 4th-order. None of the Apogee models utilized that steep a crossover...AFAIK.

Yes, just flip the cable at the speaker connection to your MRT.
That said, I am making an assumption on the relative polarity of the outputs of your XM-66 crossover. (I'm not positive on that.)
Regardless, flipping the MRT speaker connections one way or the other should yield a better sound in one configuration. That would obviously be the connection to use.

Implementing a 4th-order crossover does change the integration of the MRT/woofer and cause a more abrupt change in polar response. Strictly sound-wise, this is not a preferable change, in my opinion. But, it does have the distinct advantage of easing the load considerably on the MRT driver. Distortion is reduced, and you should no longer notice that driver visibly flopping around.

Dave.
 
Hello all,

I am changing the Apogee Duetta Signature crossover from active to passive and I have opened the panel where the speaker binding posts are. I have a few questions:

There is huge 22mF cap (Audyn) glued to the panel, but other end is not connected. Where should this copper wire be connected?

I have found two purple cables not connected. According to manual there is only one ? Actually only one has signs of wear so maybe I first try with that one? ; )

Photo from back of the panel would be great if somebody still have the original crossover.

Thanks.
 
Picture tells more than words...
Here is the photo of the crossover. Does somebody know where the 22uF cap should be connected? How about the two purple wires? For demonstration purposes I connected those in the same connector.

I am afraid that I need to open the cover and I will try to avoid that.
 

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It appears they may already be wired for passive operation. The enameled woofer inductor wire appears connected to the red woofer post. (For active operation the woofer inductor would be disconnected.)
Also, for active operation, no additional capacitor would be added like this.

It's unclear whether the previous owner had a clue what they were doing. :)
I'm sorry, but you will probably need to investigate this further so you fully understand how he "modified" these speakers.

Dave.
 
Haaa... I found the reason as I opened the cover to see the whole crossover. The mystery 22uF cap was there because there was only 5 pcs 10uF caps in the tweeter side. Maybe in the factory they did not have enough 10uF caps anymore and they put one 22 instead of two 10uF. Quick test and speaker was working in passive mode.
 
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