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Since I grabbed a pair in the sale I figured I would look around and see what I could find. On the ESS site they have the system schematics posted. Very curious to see how they sound. Have 2 pairs of 12" JBL woofers to use 2214H's or 128H-1's. They model almost the same although the 2214's were in the 4425 monitors. I plan on doing a quick listen using my Le14H-3 woofers from my Arrays. Should be fun!
http://esslabsusa.com/wp-content/upl...sedfinal-2.pdf
Rob:)
In a 3-way, I put a 5 ohm resistor in series with the Heil and treat it as an 8 ohm load using in an 8-ohm L-pad. Four ohms would also work and give a bit more volume. Caps in the range of 6.8 - ~3 mfd work well.
I also found that time alignment is very important and moving the Heil even an inch from optimal can create a suck-out in the crossover area. You really need an RTA to get the best placement.
http://www.audioheritage.org/photopo.../DSC_00011.JPG
http://www.audioheritage.org/photopo...m/DSC_0002.JPG
BTW, I can make these:
http://www.audioheritage.org/photopo.../DSC_00575.JPG
http://www.audioheritage.org/photopo.../DSC_00593.JPG
Very nice!
I like the platform for the AMT.
What mid are you using? Where do you cross them over?
Im using 2251Js for mids and 2241Hs for woofers. I've been trying different crossover points, and the 2251s can be problematic due to their response curves.
For the 2251s, I am currently using a 30 mfd first order high pass and second order, 1 mH with 6.8 mfd to gnd low pass. A resistor between the 6.8 mfd and gnd can control the brightness, but at this point I've gone from 20 ohms to 0 ohms (and many points in between) trying to get them to near the brighness of the L200/300s (which can certainly be too bright). Contrary to common sense, removing resistance makes the 2251s brighter adding to their top end.
I run the Heil in series with a 5 ohm, 25 watt Dale resistor to get ~8 ohms and use an 8-ohm L-pad. I am currenly using ~4.1 mfd to the Heil to better reach the 2251. I may go a bit bigger to dig a bit deeper to meet the 2251. The Heils seem to like a first order, ~3 - 6.8 mfd cap.
A bit more volume out of both the 2251 and Heils would be nice. The 2241s can be crossed over at 5 different frequencies (selectable inductors with second order 47 mfd cap) but the cabinets need stuffing, and this should reduce their efficiency a bit. I run a 20 ohm, 50 watt resistor in parallel with the 2241 to reduce its volume a bit without having to put the resistor in series with the woofer (possibly reducing damping?). This reduce the woofer's impedience from 8 to ~5.7 ohms, but the selectable crossover has the ability to compensate for this more or less.
I switched things up a bit, got a bit more volume, a bit smoother response, and am liking it better.
For the 2251 band pass filters, I am currently using a 30 mfd first order high pass and second order with 1 mH with 10.0 mfd to gnd low pass.
I run the Heil in series with a 5 ohm, 25 watt Dale resistor to get ~8 ohms and use an 8-ohm L-pad. I am currenly using 6.8 mfd to the Heil to better reach the 2251.
OK, this is about what is working for me. As it is now, the Heil has a 4 ohm resistor (rather than 4.74 ohm) from the L-pad and the by-pass cap has a separate 1.2 ohm resistor (rather than "conjoined" 2.37 ohm) also from the L-pad. I like to run the L-pads wide open for direct connection to the mid and tweeter (and you need to to get the efficiency to match the 2241) and the current set-up is just a bit bright. Based on the prior use of a 5 ohm resistor in this position, and no by-pass, which was just a bit "dull," I think the revisions should take care of this nicely. Waiting for the solding iron to come this week and make the changes. The 20 ohm resistor on the 2241 is to reduce its volume to match the other components, but it does raise the crossover frequency a bit.
I have 5 coil taps for the 2241H ranging from 8 to 2 mH and am using one of the middle taps. I don't see my "data sheet" so will measure this when the iron comes and I can get an accurate reading without the other components in the circuit.
These sing sweet!
http://www.audioheritage.org/photopo...c_04_12_51.jpg
I've made changes to the crossover, and this yields more pleasing results.
Granted that some of the crossover frequencies "cross," but this take the "weaknesses" of the drivers, as well as room characteristics into account. This assumes a wedgie on the Heil to take advantage of the 12 mfd cap. A larger cap drives the Heil too far into the midrange creating interference with the mid driver.
http://www.audioheritage.org/photopo...b_22_14_41.jpg