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While some people bi-amp their Vandersteens (and even claim success when doing so), it's not recommended. Bi-wiring, yes. Bi-amping, no. This is because of the crossover design. A first-order high-pass filter is essentially just a single capacitor, and driving some amps into a pure capacitive load can send those amps into oscillation. You'd be better off (IMHO) spending money on one higher-quality amp rather than two lesser-quality amps.
Passive bi-amping is no different since you're just driving half the crossover. If it's first order hp then it's a cap in series with the load which is not a "pure capacitive load". If an amp oscillates with a simple first order XO, then something's probably wrong with the amp.I've used multi-channel HT amps (e.g. an Arcam P1000) this way with no problems, but NRenter's point is a very good one about one high quality vs two lower quality amps. It becomes apples and oranges. Two stock DNA-125's would qualify as very high quality IMHO. As others suggested, there may be more effective changes elsewhere such as preamp and/or tubes. The Vandies aren't tough to drive, which opens up many good options. As another example, I drove them with a Conrad Johnson MV-50 with great results.
Passive bi-amping is no different since you're just driving half the crossover. If it's first order hp then it's a cap in series with the load which is not a "pure capacitive load". If an amp oscillates with a simple first order XO, then something's probably wrong with the amp.
THE ONLY BI-AMPING WE RECOMMEND IS WHEN YOU ADD A PROPERLY DESIGNED SUB-WOOFER THAT HIGH PASS'S THE MAIN SPEAKERS AND AMPLIFIER.WE DO NOT RECOMMEND BI-AMPING BECAUSE MANY SOLID STATE AMPLIFIERS BECOME UNSTABLE WITH THE CAPACITIVE LOAD REFLECTED BY THE MID-TWEETER SECTION. WE DO HOWEVER RECOMMEND BI-WIRING IN THE 2CE SIGNATURE OWNERS MANUAL.FOR THE MOST I THINK BI-AMPING IS OVER RATED AND NOT THE BEST WAY TO GO. BI-WIRING WITH SHORT SPEAKER WIRES FROM A 200 WATT MONO AMPLIFIER NEXT TO THE SPEAKER WILL RUN CIRCLES AROUND THE OTHER OPTIONS. I DO NOT RECOMMEND BI-AMPING ESPECIALLY SOLID STATE BECAUSE THE CHANNEL DRIVING SEE'S ONLY CAPS WHICH CAN CAUSE OSCILLATIONS AND POTENTIAL EXPENSIVE SPEAKER DAMAGE (NON WARRANTY). SUGGEST YOU GET A BETTER 2 CHANNEL AMP OR MONO'S.THIS IS A COMMON PROBLEM WITH SOLID STATE AMPLIFIERS BUT RARELY WITH TUBE AMPS. THE HIGH FREQ AMP IS SEEING THE X-OVER CAPS PROTECTING THE MIDRANGE AND TWEETER LIKE ANY SPEAKER. THIS BY ITS SELF WITHOUT THE RESISTIVE LOAD PRESENTED WITH THE WOOFER SECTION IN PARALLEL IS CAUSING THE AMP TO BE UNSTABLE. THESE AMPLIFIERS CAN NOT BE USED THIS WAY BUT SHOULD BE BRIDGED MONO AND BI-WIRED INSTEAD.I NO LONGER RECOMMEND BI-AMPING OF ANY KIND UNLESS BOTH ARE TUBE AMPS. MANY SOLID STATE AMPLIFIERS ARE UNSTABLE DRIVING THE TOP OF ALL OUR SPEAKERS. THIS CAN RESULT IN AMPLIFIER PROBLEMS OR SPEAKER FAILURE. IF CONSIDERING THIS MAKE SURE YOU USE A O' SCOPE ACROSS THE OUTPUT OF THE AMPLIFIER AND LOOK FOR OSCILLATIONS ON TRANSIENTS. MANY REPORT IMPROVED TRANSPARENCY ONLY TO FIND LATER THAT THE AMPLIFIER HAS SHORT BURSTS OF OSCILLATION TRAILING ALL TRANSIENTS. LISTEN TO BOTH OF YOUR AMPLIFIERS AND PICK THE BEST ONE, BI-WIRE TO YOUR 3A SIGS AND PLAY MUSIC.THIS IS NOT RECOMMENDED AS THE CHANNEL HOOKED UP TO THE MID-TWEET WILL SEE ONLY A CAPACITIVE LOAD WITH NO GROUND RETURN. THIS WILL CAUSE BURNT PARTS IN THE X-OVER BECAUSE THE AMP IS OSCILLATING AT VERY HIGH FREQUENCIES. THIS IS WHY SOME PEOPLE THINK IT IS MORE OPEN BECAUSE IT IS BRIGHTER. THE BEST ALTERNATIVE IS MONO AMP WITH SHORT SPEAKER WIRES. THE MONEY SAVED ON SHORT WIRES WILL BUY A BETTER PAIR OF AMPS.YOU COULD HAVE AN UNSTABLE AMPLIFIER BECAUSE OF BI-AMPING. WE DO NOT RECOMMEND BI-AMPING THE SPEAKERS FOR THIS REASON. SELECT YOUR BEST SOUNDING AMPLIFIER AND BI-WIRE IT TO YOUR SPEAKERS.IT CAN CAUSE AMPLIFIER UN STABILITY WHICH CAN FRY TWEETERS. TRY AT YOUR OWN RISK!WE RECOMMEND BUYING ONE STEREO AMP OR TWO MONO'S OF HIGHER QUALITY AND BI-WIRING THE SPEAKER. SAME MONEY BETTER SOUND. ALWAYS FOLLOW THE AMP MANUFACTURES RECOMMENDATIONS SO THEY WILL HONOR THE WARRANTY. IT COULD DAMAGE THE SPEAKER IF THE AMPLIFIER BECOMES UNSTABLE. WITH ONLY 8 W AVAILABLE IT WOULD BE CLIPPING INTO THE MID RANGE AND TWEETER ANYWAY BURNING THE VOICE COILS. I DO NOT RECOMMEND BI-AMPING WITH TWO CHANNELS AS MANY AMPLIFIER BECOME UNSTABLE AND BURN TWEETERS. YOU SHOULD USE A SECOND SET OF WIRES AND BI-WIRE ACCORDING TO THE OWNERS MANUAL. IT IS NOT UNCOMMON FOR TWEETERS TO FAIL WHEN BI-AMPING WITH SOME AMPLIFIERS BUT CAN TAKE SOME TIME. I WILL SAY ONE MORE TIME THAT YOU WILL GET MUCH BETTER SOUND WITH A PAIR OF MONO BLOCKS WITH SHORT WIRE THAN BI-AMPING. TAKE THE MONEY SAVED ON SHORT VS LONG QUALITY SPEAKER WIRE THE COST OF TWO QUALITY STEREO AMPLIFIERS AND INVEST IT IN A PAIR OF HIGHER PERFORMANCE MONO AMPLIFIERS THE SOUND WILL BE BETTER I ASSURE YOU. WHEN BI-AMPING WITH A 70 WATT STEREO AMPLIFIER YOU ONLY HAVE 70 WATTS AVAILABLE TO EACH DRIVER NOT 140. MOST AMPLIFIERS RING ABOUT 3 TO 4 CYCLES WHEN DRIVING THE CAPACITIVE LOAD REPRESENTED BY THE UPPER SECTION OF THE 3A SIG. THIS ADDITIONAL RINGING IS NOT IN THE SOURCE AND CAUSES THE SOUND TO BE A BIT BRIGHTER (OPEN). IF YOU LIKE IT THAT IS GOOD JUST THOUGHT YOU SHOULD KNOW WHAT IS GOING ON.TIME AND TIME AGAIN I HAVE STATED IN THIS FORUM THAT I DO NOT RECOMMEND BI-AMPING BECAUSE OF POTENTIAL STABILITY PROBLEMS. WE DO NOT RECOMMEND ANY KIND OF BI-AMPING. THE ONLY BI-AMPING THAT OFFERS A PERFORMANCE IMPROVEMENT IS WHEN YOU ADD A PROPERLY DESIGNED POWERED SUB-WOOFER LIKE OUR 2WQ. IF YOU INVEST THE SAME AMOUNT OF MONEY IN MONO BLOCK AMPS AND BI-WIRE, IT WILL ALL WAYS OUTPERFORM ANY FORM OF BI-AMPING.THIS IS WHY WE NO LONGER RECOMMEND BI-AMPING AS THE CHANNEL THAT IS DRIVING THE HIGH SECTION IS VERY CAPACITIVE AND CAN CAUSE MANY AMPLIFIERS TO BECOME UNSTABLE. YOU ARE LUCKY THERE WAS SUCH AN OBVIOUS PROBLEM BECAUSE MOST OF THE TIME IT JUST GETS BRIGHTER, THE AUDIOPHILE THINKS MORE DETAIL (AMP RINGING) AND IN A COUPLE WEEKS OR YEARS THE TWEETER QUITS????????? THE RINGING CAN PUT OUT NEAR FULL POWER INTO A TWEETER V.C. ON SOME TRANSIENTS AT FREQUENCIES NOT AUDIBLE TO US BUT VERY DAMAGING.I DON'T RECOMMEND BI-AMPING FOR MANY REASONS. I THINK THE PARASOUND HCA SHOULD SOUND FINE AND CAN'T FIGURE WHAT BI-AMPING WOULD HELP ANYWAY. NEVER BI-AMP WITH TWO DIFFERENT AMPLIFIERS.I DO NOT RECOMMEND BI-AMPING BECAUSE THE AMP DRIVING THE UPPER SECTION DOES NOT HAVE A DC RETURN IE: IS CAP COUPLED. THIS CAN CAUSE MANY AMPS TO OSCILLATE AT HIGH FREQUENCIES DAMAGING THE TWEETERS WITHOUT ANY NOTICE. I PREFER THE WIRE THAT SOUNDS BEST REGARDLESS HOW ITS MADE.
So I guess I will be looking at tube preamps now. I cannot afford his Leben or Shindo preamp and he does not carry a ARC that would match either. I am now looking at Rogue, Eastern Electric preamps and integrated and the Primaluna line. Anyway thanks for the info...Tube preamps to suggest? Older ARCS??
