some amps can do it, I don't know especially about this Alpine, but I assume it's a 2 ohm stable 4 channel variety.Ive always wondered if this will work or if the amp will commit suicide.
Specifically, taking a Alpine MRP-F300 and have channels 1/2 running on a 2 ohm load, while channels 3/4 are running on a 4 ohm load.
Anyone know anything on this subject?
not necessarily.said that better than i could have, for most cases you want to run the same impedance across all channels,
more explanation is necessary here.Thanks, I figured if it was possible it would only be certain amps.
And sorry should have specified beforehand, Im running active so two channels would be playing 60-1500hz (4 ohms), the other two would play everything up from there (2 ohms). I just figured since its stable at 2 and 4 ohms it could possibly do both at the same time and feed my highs the extra 25W.
damn! that is a big differenceto be honest highs require much less power as is to blend with the lower frequencies, i honestly wouldnt worry about it. some high end tweets require much more power to sound how they are suppose to, high end comp sets running active often times are running 200rms to each tweet...but for your setup like i siad... no big issue
for instance my midbass drivers are rated "rated" 150rms, with my tweets only want 15 rms,,, huge difference in power there, 1/10th of my mids
damn! that is a big difference
The reason I am wanting to squeeze a few more watts out to the highs is I'm about to play around with a 3-way setup by reinstalling my old tweeters on the same two channels as my current "tweeters" (CDT ES-02 mid/tweeter) with an inline ~4kHz hpf to see if it helps a slight blending issue im having.
I realized with the two 4 ohm drivers i could now run a 2 ohm load and draw the 75w so I'm not giving the CDT's that much less power.
Hmm, ill be honest I didn't know there was another way besides a passive crossover. :stunned: Could you point me in the direction of a write up on the capacitor method? And possibly explain why a passive crossover could short it out?this sounds safe enough.
you're taking everything above 4 Khz into 2 ohms at the amp, when you parallel the CDT with the old tweeters. However, if you're using passive crossovers that came with a component set, on those old tweeters for your 4 Khz and up, you could put the amp into a near short condition because of how some passive crossover networks are configured.
If you're just adding a capacitor to the old tweeters for your 4 Khz and up crossover, then it's okay.
You see, it's not always obvious if a change in your set-up is harmful or not.
a 12 db/oct passive, is a capacitor and inductor together in circuit.Hmm, ill be honest I didn't know there was another way besides a passive crossover. :stunned: Could you point me in the direction of a write up on the capacitor method? And possibly explain why a passive crossover could short it out?
Im glad you brought that up, I would never have thought that was possible. I was going to get one of those inline one way high pass filters, for the tweeter wire only, from parts-express to test the idea before I bought a nice one. Bad idea?a 12 db/oct passive, is a capacitor and inductor together in circuit.
a capacitor is still a passive crossover, it's just a 6 db/oct slope.
when some passive crossovers are connected only to the woofer, or only to the tweeter, depending on the amount of circuits involved you could have a portion of the frequency spectrum running an impedance near 0 ohms. This could cause an amp to go into protect or just overheat without any warning signs and self destruct.
there's no real method, it's just practicing safe crossover sex. Make sure your passives if they have outlets for woofer and tweeter, have both outputs connected to speakers.
You might never run into this problem but I've damaged amps myself because I didn't know it was possible.
You will see warnings and things in component speaker manuals but it's easily missed in the heat of installing, and easily forgotten if you don't go back and read the manual before re-installing later.