2. amps-preamps
  3. 128332-4156

Why does bi-amping speakers sound better?

Curious why it sounds better to bi amp speakers vs just running them off one amp?

i am trying to figure out which amp to buy, I am on the fence with bi amp or not.  Speakers are the old infinity kappa 8.1's.  Several years ago when I was married I bi amped my speakers so each speaker was seeing two channels from a parasound hca1500, I think that's the model.... 200w x 2 going to each speaker.  I also tried a single amp powering both speakers so each speaker was seeing 200w x 1.  

is it that I simply doubled the power that resulted in better sound, mostly noticed the low end of the speakers was tighter, more powerful etc.... and obviously I could also play louder.  

Or is is there something about letting one amp not work as hard due to only running high frequencies while the other amp gets to just work on the low end.  

I am 90% sure which brand of amp I want to get, just trying to figure out if I should bi amp or not.

as a example should I go with

two 2 channel amps at 400w x 2 so each speaker would get 400x2

or should I go with a single 800w stereo amp so each speaker sees the same 800w, just with one channel of a amp



128x128viggen900
gdnrbob
4,407 posts
 
Since you are dealing with old wiring, I would get an electrician to look at what you have, before buying an amp. 
If it will tax the existing wiring, you will not only not hear what you could achieve, but might not only damage your equipment, but may exacerbate a fire. Going over 200wpc is really sucking up juice.
meerzistar
232 posts
 
audioman201581 posts02-10-2017 9:16amIn bi-amping, each amplifier drives a less complicated load. The drivers along with the crossover components have a complex impedance. It consists of a real load and then the imaginary part based on inductors and capacitors. This complex load also varies depending on the frequency of the signal. So if you have a 2 way speaker, the complete load a single amp will see is driver1+driver1 crossover+driver2+driver2 crossover. This is a much more complex load that the amp sees vs just driver1+ driver1 crossover.

Theres less complication by eliminating the passives it also equates to zero heat being generated within them relieving that much more strain from the amplifier. If the speakers have large complex crossovers with 1-3 big coils and 4-5 big caps you could be freeing up a good percentage of power that can then be routed directly to the drivers

I had once put together a small 30 x 4 channel Nad w Ashley pro crossover used to power some rather large mediocre efficient home made speakers, it did a fine job. Around $500 bought quite a lot of fun
terry9
2,209 posts
 
I have used an active bi-amp topology for both Magnepans and Martin-Logans: preamp - electronic crossover - amplifiers. Sounded vastly better than stock, mostly because an electronic crossover only has to shape a tiny signal, and so very high quality components cost little. Think of the difference between dividing the water from a roof drain and dividing the water of the Mississippi. I used Brystons for the bottom and Atmospheres for the top.

But there is a better solution, which I use now. Why not use a speaker with no crossover at all? Quad electrostatics, for example. Save all that money for an active crossover, extra amplifier, and all that extra power, and invest in a better speaker.

Also, if you're doing wiring anyway, consider wiring in an isolation transformer, which gives you the ultimate clean power. Makes a difference you can hear, as well as protects your equipment. Word of caution - they can growl when they are doing their job, so keep them away from your living or listening areas. Plitron makes a good one.
bigkidz
3,307 posts
 
atmasphere is correct.  Bi-wiring does not always equate to better sonics IMO.  I find it hard to understand most of the threads on audiogon that do not explain what the outcome is that someone is looking for.  What is it that you want form your system?  More watts do not equal better sound.  With the original Adcom amps the 100 wpc amp was better sounding then the 200wpc amp.  It is hard to build a more powerful amp and get better sound form the lower powered amp.  You just cannot double the parts.  Better sound as I have stated too many times already IMO comes from the source.  An amps current also has an impact on the sound.  I have an old Lafayette kit tube amp that is 35wpc and will drive most any speaker out there.  It was build using fantastic transformers.  Class D amps are relatively cheap so you and buy them and try them to hear what they do in your system.

Happy Listening. 
meerzistar
232 posts
 
I will whole heartedly agree that bigger doesn't always mean better, even given amps are similar build and quality. Or that biamping is your ticket to sonic heaven. Everything has to have that "magic" brew and work together. Amplifiers have sweet spots also, and seem to sound very best in specific ranges.  

I hope that old all power amps sound the same argument doesn't resurface.  
More to discover