| Re: Increasing Q with a 4 Ohm Resistor.
In addition to all that has been said, if the driver was wired as a 4 ohm load, then one half of the power would be wasted as heat by the resistor.
So, lets assume you had a 400 watt amplifier... (into 4 ohms)
By adding a 4 ohm resistor in series, you now have a 8 ohm load.
That would result in roughly 200 watts power from that same amplifier into an 8 ohm load... or 100 watts of power for the sub, and 100 watts wasted as heat by the resistor.
Thinking further... ever grabbed hold of a 100 watt light bulb after it has been on for a while... or grabbed hold of the hot end of a soldering iron (most of them are 25-35 watts... so think three times as much heat)? In either case, you can get an idea of how hot the resistor will get. You will need a very hefty resistor to handle the heat, if nothing else.
All told, in my opinion, your friend knows very little about basic electronics, since he said "add the resistor in series with the positive lead" Since the resistor is in series (assuming that is what he meant) it does not matter where it is put in series... positive lead, negative lead, close to the driver, or close to the amplifier...
I'm sure you mis-understood him some way. Perhaps he wanted you to put the resistor across one of the dual voice-coils on that AA driver, and feed the other voice coil from the amplifier. That will affect its T/S parameters.
Joe L.
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