Biamp question


I have a biamping question. I am thinking of biamping leagacy audio signature se speakers using a ss Parasound a21+ for LF and a rogue st 100 for HF. I am using a rogue rp7 preamp. Anyone have any input on if this will work or not? Thanks. 

backdoor

If I’m not mistaken don’t you need to make sure that both apps have the same amount of gain?

My experience with using very different amps (LF = PP KT88, Class D GaN, Class AB SS and HF 2A3 SET) that within my listening range (75 db - 100 db) they all match within a db or so. So the "gotta have the same amps" thing is something I don’t believe in, but you must have a way to adjust either the HF or LF output so the two match.

What I do is measure the outputs to make sure the high and low outputs track:

I use a RS meter about 1 foot in front of the HF driver with the LF amps turned off and adjust the main volume so the meter reads 85 db when playing a 2K Hz tone.

Then I put the meter about 1 foot in front of the LF driver with the HF amps turned off and adjust the output of the LF amps so the meter reads 85 db when playing a 500 Hz tone. Now the outputs are matched at 85 db.

Then I adjust only the main volume and play 75 db, 80 db, 90 db (already baselined at 85 so no need to do that again), 95 db, 100db measuring LF at 500 Hz and HF at 2K Hz and see how close they track.

 

The gain on Parasound is adjustable so I believe I should be able to match the gain by adjusting on the Parasound to match the Rogue. I’m pretty green here so not sure that makes sense or not. 

The gain on Parasound is adjustable so I believe I should be able to match the gain by adjusting on the Parasound to match the Rogue.

If the output of the Parasound is louder than the Rouge then you are good. But if the Rouge plays louder, turning the Parasound down won't work.

 

I guess I won’t know that until I try it. On the crossover question, I want to get a crossover that already matches the crossover points of the speakers. Is that pretty accurate?

I guess I won’t know that until I try it. On the crossover question, I want to get a crossover that already matches the crossover points of the speakers.

External XOs are adjustable. I use the First Watt B4, Marchand makes them, and several other manufacturers.

Typically on these XOs there is one input (connected to your preamp out), and two outputs connected to your Parasound and Rouge amps: High frequency and low frequency. So 20 Hz - 20 KHz (nominally) goes from your preamp into the XO and you set what range of frequencies comes out of the LF and HF outputs. So you can set the outputs to match the XO points the speaker manufacturer designed.

Note that this discussion about external XOs is only if you will not be using the internal crossovers built into your speakers.