anyone bi amp a pair of ess amt1d active xo ?

neck deep in this project.
Using a rane AC22 active crossover
2 X ADCOM 5400
Integra 7.8 pre out

A/B - ing both speakers (one standard using the ess passive xo the other using the Rane xo set to 800hz) i find the mid and mid highs harsh. tweaking the xo point up to 900/1000/1100/1200 did not help much.

Any help via experience would be great!!

What slope are you using? What are the passive crossover specs for that model?
The Rane xo has a 24bd slope.
I have tried to get specs from Ricky at ESS but no deal!
The ESS crossover has the heil at 800hz.

thanks for the response!!
The slope may be to steep. I'm not familiar with the Rane other than i have seen a picture. I would say your ESS would have a slope at 12db/octave and the slope would finish around 800hz not begin at 800hz
The woofer would also phase out completely around 800hz at 12db. You may need to start your slopes around 650-700hz for a smoother transition at 12db
That's funny - I am doing a biamp on my AMT 1Cs with that same crossover - Rane AC22. My amps are a Pioneer for the tweeters, and a Crown for the woofers.

Like you, I am also using a modern receiver for the pre-pro. In my case, a Denon 3808CI. What I did, with great results, was to the bias the crossover in favor of the woofers slightly to make sure the bass isn't lost, and then run Audyssey, which does a fantastic job of correcting the frequency response irregularities of the drivers, which the original crossovers took care of.

In your case, that's tough because you are trying to side by side them, which I can understand. But I found the results excellent. I am also using Audyssey XT, like your Integra.

Let me know what you think!

Oh, I used 800Hz for the crossover point.

Wow - thanks!!!
We are basicly doing the same deal!
I dont quite get the audyssey integration - can you give me some detail, this will be my next activity!
As you probably already know, Audyssey does a fantastic job of correcting speaker response in the room. In a way, it acts like an equalizer, except without many of the downsides of an EQ. It also corrects time delays, and other things.

Well, when you calibrate your system with Audyssey, it's meant for room modes, assuming your speakers are already close to flat. Well... if you speakers aren't flat, Audyssey still fixes it, within the limits of what it can correct. Try to get it as close as you can, while biasing it a little to the lower end (that's just my experience; yours may be different). Then run the full microphone calibration like you normally would. I think you'll be happy with the results. I know I am. :)

How'd it go? BTW, you will need to use it on 'stereo' mode or another mode where Audyssey is active for best effect.

Thanks IBJAMON!!
I have not got there yet.
Still working the side by side audio comparison.
Thought to adjust the Q using the Rane by using both channels (one for low) & (one for high)this would enable 2 points of adjustment using 2 XO points.
Still dorking with it and will supply an update soon!
I'm curious what crossover point you settle on - I left it at 800Hz. Going in each direction has potential consequences, so I figured since ESS's active crossovers were 800Hz, I would leave well enough alone. But who knows - something better could be possible, though I would think a higher xover point would need something other than a 12" woofer.

I look forward to your results!

Any luck with this? I don't assume that my setup is perfect but it gets the job done... I'm curious if you found something better.


well the process has taken a u turn - i live next to a hifi shop and i should never go into it! This whole upgrade process opened my mind up to other options (or speakers) that i may be missing out on (having this set of AMT 1D's for 17 years) long story short - i purchased a set of martin logan vista's.

my experiment is over - sorry i could not supply you with any other info!!

Take care!
Oh well, that's too bad. Enjoy them! Make sure the ESSs go to a good home.

try doing a +- swap on one driver....probably the tweeter.
IF the crossover phases ADD at the crossover point, it may be too much. If the original crossove was such that the speaker had to be wired in or out of phase to be correct, you may simply need to swap......

Example: my maggies have a 1st order hi pass / 2nd order lo pass. The 2 drivers are wired out of phase. Good even response thru the crossover region.
IF I swapped the tweeter, it simply wouldn't be or sound right.