Thanks for that. You wouldn't like to draw the circuit would you? 😉
If that resistor is definitely in series with your tweeter, which I think is a nominally 8 ohm unit, then it's giving around 3 dB of attenuation.
If you were to stick with a single resistor attenuator then you'd have to up the value to 8 ohm for around 6 dB of attenuation.
No, as that would decrease the resistance value. Resistors must be in series to add up in value, not parallel.
P.S. An L pad would be preferable as it won't upset the crossover frequency (R1 = 3.9 ohm and R2 = 10 ohm would attenuate an 8 ohm tweeter by 6 dB).
I can't see it well enough to be sure.. but it looks something like this. (The other resistor might also be a capacitor)
To help decide, there's what looks like a second resistor on yomav's board, but there's only one on the photo of the board I found.
Can you give an input as to how to provide tweeter attenuation in the above circuit - adding an L pad would be feasible?
I think the tweeter is 8 ohm nominal, at least that's what it says on replacement coil/diaphragms for the KG2 tweeter. However the system impedance is stated as 4 ohm.
P.S. Thanks for the schematic.
Assuming as you say and switching in two new resistors. The red trace is as shown in the schematic the one beneath uses the leftmost resistor instead and the upper is with neither.
Oethers may have addressed this, but 800 Hz is a bit too low IMHO. You can do 1,500 with that 8" driver, probably, which will reduce the power demand on the planar.
@AllenB EDIT: I'm confused as to what to tell yomav to do.
@eriksquires That has not been addressed, but it did cross my mind that a higher crossover frequency would be kinder to the tweeter.
@eriksquires That has not been addressed, but it did cross my mind that a higher crossover frequency would be kinder to the tweeter.
Thank you…so I just wire connect R2 (10 Ohm) from the + to the - terminal of the tweeter…and have R1 (3.3 Ohm) wired in front of the positive terminal of the tweeter.
Purchased.
It's just that it has been suggested that a slightly higher crossover frequency (say 1.0 to 1.5 kHz) would beneficially reduce the share of the system power that the planar mid/tweeter has to handle.
However, provided you are not in the habit of constantly playing your music at stadium levels, 800 Hz should be OK.
You certainly should not turn the amplifier all the way up in order to see how loud the speakers will go!
However, provided you are not in the habit of constantly playing your music at stadium levels, 800 Hz should be OK.
You certainly should not turn the amplifier all the way up in order to see how loud the speakers will go!
The physical offset between the two drivers (how close is each one to you) will also be a factor. If you can build your speaker with flexibility to move the planar back and forth that might help you find success.
I've heard with those planars, don't solder wires to the terminals. The heat will conduct up the leads and melt the membrane. Home Depot or Amazon will sell you quick connects that should fit, you might find a cheap kit with a crimper and variety pack of connectors. IDK the tab size off-hand...
I've heard with those planars, don't solder wires to the terminals. The heat will conduct up the leads and melt the membrane. Home Depot or Amazon will sell you quick connects that should fit, you might find a cheap kit with a crimper and variety pack of connectors. IDK the tab size off-hand...
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Yes; I’ve read the same regarding keeping heat away from planar membranes (and thus terminals)
I have a good assortment of connectors.
Nice idea with the planar positional adjustability.
I have a good assortment of connectors.
Nice idea with the planar positional adjustability.
@yomav @AllenB
I've found the crossover schematic for the Klipsch KG2:
You may attenuate the tweeter by adding a resistor in series with the negative terminal of the tweeter (following the 8 uF capacitor).
Try a 3.3 ohm (5 W or 10 W) resistor first, increasing the value if necessary.
EDIT: I should clarify that yomav is using the Klipsch KG2 crossover in conjunction with an Infinity QA driver and a Heil tweeter.
I've found the crossover schematic for the Klipsch KG2:
You may attenuate the tweeter by adding a resistor in series with the negative terminal of the tweeter (following the 8 uF capacitor).
Try a 3.3 ohm (5 W or 10 W) resistor first, increasing the value if necessary.
EDIT: I should clarify that yomav is using the Klipsch KG2 crossover in conjunction with an Infinity QA driver and a Heil tweeter.
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This will be an open baffle design.....sort of what I did previously in the picture I posted earlier in the thread.....but this time with more finesse.
Thanks @yomav.
I suggested a simple solution involving a single series resistor in post # 37, but a better solution is to use an L pad in front of the tweeter.
If your Heil tweeter is 4 ohm, then R1 = 1.8 ohm and R2 = 4.7 ohm would attenuate it by around 5 dB. Use resistors of minimum rating 10 W.
Come back if you require an alternative calculation.
I suggested a simple solution involving a single series resistor in post # 37, but a better solution is to use an L pad in front of the tweeter.
If your Heil tweeter is 4 ohm, then R1 = 1.8 ohm and R2 = 4.7 ohm would attenuate it by around 5 dB. Use resistors of minimum rating 10 W.
Come back if you require an alternative calculation.