Biamping with active xovers before the amps can do all this. Biamping with 2 amps, each feeding into a single speaker before passive hi and lo pass filters already in there? A few db of dynamic range, maybe, but essentially a fad, marketing hype, a way of selling another amp.
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Bi amping
- Thread starter Thomas savage
- Start date
The result will as well depend on the listener's unconscious cognitive biases toward what they have spent money on, goes without saying
RealityCheck18
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So there I was (say it isn't so!)
The 1990's and I was "that guy" because my car stereo sounded very good and completely stealth--no indication there was a system at all. I also ran PA systems for fun (and very little profit) on the weekends so that added additional street cred. Car audio can be very confusing because it is dominated by testosterone, people in their teens/20's, marketing and ignorance. After all, the idea of "picking up chix" with audio gear tends to lead you down a path of an empty wallet and loneliness. I learned quickly that audio gear does not attract women, it repeals them so best to hide it as best as possible.
Anyhoo, the first thing I would tell people when we were in the design phase was correct terminology--DON'T use "bi-amp, tri-amp" etc...it is "Active, passive or semi-active" The Beatles broke up 25 years ago, Lennon died 15 years ago so use the term active so to not cause confusion. Gernally, what they ended up with was either a semi-active or fully active system for their cars. Electronic crossovers, delay, EQ, measurements and all that sort of entertainment. My system was active with tweeters, 4" mids, 6.5" woofers and a 10" ported subwoofer properly high passed and tuned to the specific car. Very common for active systems in cars back in the 90's--any advantage you can get when dealing with the horrible acoustics and lack of placement options is a good thing. For more reasonable people, I tended to use passive crossovers for the mid to tweet section, then active for the woofers and subwoofers along with proper EQ.
Active systems was how I did my PA system--for the most part. The tweeter/mid was passive but the woofers (bass bins) were active and so were the subwoofers. I didn't do that to make it sound better, I went active to conserve power AND most importantly--to prevent blowing out speaker drivers. The high-mid was limited at 250 watts, the bass bins at 750 watts and somewhere around 1KW for the subs. The clubs had mutliple breakers on the stage so it was OK.
Active systems demand you understand what you are doing--if you don't, a fun way to turn drivers into fuses. This is not optional, it don't matter if it is car audio, PA systems, boomboxes or consumer speakers--you will damage the speakers if you don't fully understand what you are doing. It is not hard to do, thousands of high school kids every year install fully active systems in their cars and don't blow them up. You can do it!
The ability to run active is common in car audio and PA systems--you'll tend to see different inputs and a switch. The switch bypasses the passive crossover and you change from "full range" to "active" inputs (see user manual for warnings) Now you can connect the active crossover to the amplifiers and split the signals before the amplifiers, apply delay, parametric EQ and keep all your processing in the digital domain before it gets amplified. This not only improves efficiency, it can also improve sound quality and prevent driver damage during gigs. Blow a driver at the house, it is annoying--blow a driver at a gig and rumor has it that hundreds of drunk people tend to disprove of dead air, say nasty things about your mom, call your sexuality into question and throw things.
Something to chew on--it goes along the lines of common sense. I have never seen a pro sound speaker with passive bi-amping terminals--not a single one! There might be one, never know but the ones I see are passive or active--no passive stuff. Technically, you could modify the crossover by splitting it into high pass/low pass filters and rewire the terminals to make it that way--I've never seen it done. You can also do that in car audio, well you could--never saw passive bi-amping in car audio....never know it might exist but is never brought up to fix a real world problem.
Why then that ONLY in consumer sound is "passive bi-amping" a thing? Simple, it sounds cool, it looks cool and you can then hang out with the cool kids with active systems--without knowing what you are doing! True, it does allow you to adjust the drivers gain to go up or down which is a "feature" I guess--because EQ is bad, mmmmkay! You can change the sound with passive bi-amping--you can! However, generally speaking the manufacturers have a higher level of understanding about audio than you do so most people don't mess with changing the gains. It will allow you to screw around with the speakers-without blowing them up. Well, if you crank the gain +20dB higher for the tweeter over the woofer you'll fry them but generally speaking you should be OK.
Maybe in the future you'll find high performance speakers with passive and active switching to allow easy active processing to be added. I fully understand why consumer gear does not have that option. Way to easy to blow the speaker drivers if you don't know what you are doing. But, but, but I can bi-amp my AVR and it blew out tweeters when I put it in the active connectors--bad design! Let me trash them on Amazon and warn other people it is a bad design! You KNOW that wil happen! If the typical audiophile has not figured out speaker wire, power cords and what a digital signal is--it would kill your company if you assumed they understand how speakers work---or worse, would alctually read the operators manual. On the pro side, it is assumed you know what you are doing, assumed that you read and understand the manual, assumed you use EQ and it is assumed you are competent in what you are doing. If not, you blow it up it is YOUR fault and whining online because you did it wrong does not carry any weight.
I get it, sure.. Revel is supposed to be truthful and all that yada, yada crap but they have to eat. They know 100% that it is bogus and actully makes their speakers worse (adding mechanical connections to crossover boards adds resistance) McIntosh learned back in the 70's about speaker wire, they used to throw speaker wire in with their speakers that worked perfectly well. The audiophiles complained that the wires were not big enough, no magic whatever and so on...McIntosh quit throwing in free proper wire to shut them up. The dealers then could sell whatever magic wire they wanted because McIntosh has to make a profit.
Now those $4,000 a pair Revel bookshelf speakers? They have a single set of terminals, no "passive bi-amping" crap available because they are not aimed at consumer/audiophile market. The mass market stuff has that crap because you tailor it to your customer. You don't think that a JBL 4722N theater speaker has passive bi-amping terminals do you? It can be passively done or actively done--because of market demands. Yes, a consumer can purchase those speakers for their basement--and people do but it is not consumer friendly. No gloss black, no grills--hell, the horns sits on a flat black box and you can see the crossover/input boards.
Doubling the size of something, wasting electricity, generating heat and throwing away resources to gain nothing tend to go against my way of thinking. Even if cost did not matter, designing something that is horrifically wasteful just to avoid doing it right I really don't understand. It reminds me of the kids that put giant exhaust tips and big wings on their FWD econoboxes to make race cars---uhhhh, you are actually making it slower but everyone did stupid things when they were kids--you get a pass. Now when a 35 year old guy does that to their car, they are either a pedo creep or tragically ignorant--you don't get a pass when you are 35!
Now if you DO want to join the ranks of the cool kids and actually improve your sound--you can (technically) call it "active bi-amping" by using subwooers that naturally have electronic adjustable crossovers, delay and so on. Not only can you say it is "bi-amped" but also say it uses active bass management Any pair of speakers can be improved with proper subwoofers placed, measured and spec'd properly so you won't be wasting amplifiers as they will actually improve your sound. It is very, very hard to blow up subwoofers--so you don't need to fully understand the ins ad outs of tweeter/mid protection, filter types, filter slopes, Fs of drivers, power handling and so on. So, if you want to start your active bi-amping journey without blowing stuff up, crossing subwoofers to your main woofers is your safest bet and WILL improve your sound quality, response across multiple seats and lower distortion. A great place to screw around with all sorts of settings to learn what they do without frying drivers.
Edit! I do remember Blaupunkt made a "passive bi-amp" 6x9 years ago. It was a dual voice coil 6x9 woofer so you could add an amp to "increase the bass" or somehig. Uhhhh....it increased the bass, increased the mids and increased the volume of the woofer breakup modes soooo....they quit producing the thing (late 80's???) The midrange and tweeter had blocking caps on them and I think th 6x9 had a simple inductor coil high pass. It made a splash then vanished from their lineup never to show up ever again. Since it has been decades--I am assuming that thing was not copied by other manufacturers.
Just another angle of thinking--what do the professionals do when money, their job and thousands of paying patrons are thrown into the mix? It is not exact but when some audiophile thing only exists on the consumer audio side, it does call for one to ponder why. Hmmmm...
The 1990's and I was "that guy" because my car stereo sounded very good and completely stealth--no indication there was a system at all. I also ran PA systems for fun (and very little profit) on the weekends so that added additional street cred. Car audio can be very confusing because it is dominated by testosterone, people in their teens/20's, marketing and ignorance. After all, the idea of "picking up chix" with audio gear tends to lead you down a path of an empty wallet and loneliness. I learned quickly that audio gear does not attract women, it repeals them so best to hide it as best as possible.
Anyhoo, the first thing I would tell people when we were in the design phase was correct terminology--DON'T use "bi-amp, tri-amp" etc...it is "Active, passive or semi-active" The Beatles broke up 25 years ago, Lennon died 15 years ago so use the term active so to not cause confusion.
Gernally, what they ended up with was either a semi-active or fully active system for their cars. Electronic crossovers, delay, EQ, measurements and all that sort of entertainment. My system was active with tweeters, 4" mids, 6.5" woofers and a 10" ported subwoofer properly high passed and tuned to the specific car. Very common for active systems in cars back in the 90's--any advantage you can get when dealing with the horrible acoustics and lack of placement options is a good thing. For more reasonable people, I tended to use passive crossovers for the mid to tweet section, then active for the woofers and subwoofers along with proper EQ. Active systems was how I did my PA system--for the most part. The tweeter/mid was passive but the woofers (bass bins) were active and so were the subwoofers. I didn't do that to make it sound better, I went active to conserve power AND most importantly--to prevent blowing out speaker drivers. The high-mid was limited at 250 watts, the bass bins at 750 watts and somewhere around 1KW for the subs. The clubs had mutliple breakers on the stage so it was OK.
Active systems demand you understand what you are doing--if you don't, a fun way to turn drivers into fuses. This is not optional, it don't matter if it is car audio, PA systems, boomboxes or consumer speakers--you will damage the speakers if you don't fully understand what you are doing. It is not hard to do, thousands of high school kids every year install fully active systems in their cars and don't blow them up. You can do it!
The ability to run active is common in car audio and PA systems--you'll tend to see different inputs and a switch. The switch bypasses the passive crossover and you change from "full range" to "active" inputs (see user manual for warnings) Now you can connect the active crossover to the amplifiers and split the signals before the amplifiers, apply delay, parametric EQ and keep all your processing in the digital domain before it gets amplified. This not only improves efficiency, it can also improve sound quality and prevent driver damage during gigs. Blow a driver at the house, it is annoying--blow a driver at a gig and rumor has it that hundreds of drunk people tend to disprove of dead air, say nasty things about your mom, call your sexuality into question and throw things.
Something to chew on--it goes along the lines of common sense. I have never seen a pro sound speaker with passive bi-amping terminals--not a single one! There might be one, never know but the ones I see are passive or active--no passive stuff. Technically, you could modify the crossover by splitting it into high pass/low pass filters and rewire the terminals to make it that way--I've never seen it done. You can also do that in car audio, well you could--never saw passive bi-amping in car audio....never know it might exist but is never brought up to fix a real world problem.
Why then that ONLY in consumer sound is "passive bi-amping" a thing? Simple, it sounds cool, it looks cool and you can then hang out with the cool kids with active systems--without knowing what you are doing! True, it does allow you to adjust the drivers gain to go up or down which is a "feature" I guess--because EQ is bad, mmmmkay! You can change the sound with passive bi-amping--you can! However, generally speaking the manufacturers have a higher level of understanding about audio than you do so most people don't mess with changing the gains. It will allow you to screw around with the speakers-without blowing them up. Well, if you crank the gain +20dB higher for the tweeter over the woofer you'll fry them but generally speaking you should be OK.
Maybe in the future you'll find high performance speakers with passive and active switching to allow easy active processing to be added. I fully understand why consumer gear does not have that option. Way to easy to blow the speaker drivers if you don't know what you are doing. But, but, but I can bi-amp my AVR and it blew out tweeters when I put it in the active connectors--bad design! Let me trash them on Amazon and warn other people it is a bad design! You KNOW that wil happen! If the typical audiophile has not figured out speaker wire, power cords and what a digital signal is--it would kill your company if you assumed they understand how speakers work---or worse, would alctually read the operators manual. On the pro side, it is assumed you know what you are doing, assumed that you read and understand the manual, assumed you use EQ and it is assumed you are competent in what you are doing. If not, you blow it up it is YOUR fault and whining online because you did it wrong does not carry any weight.
I get it, sure.. Revel is supposed to be truthful and all that yada, yada crap but they have to eat. They know 100% that it is bogus and actully makes their speakers worse (adding mechanical connections to crossover boards adds resistance) McIntosh learned back in the 70's about speaker wire, they used to throw speaker wire in with their speakers that worked perfectly well. The audiophiles complained that the wires were not big enough, no magic whatever and so on...McIntosh quit throwing in free proper wire to shut them up. The dealers then could sell whatever magic wire they wanted because McIntosh has to make a profit.
Now those $4,000 a pair Revel bookshelf speakers? They have a single set of terminals, no "passive bi-amping" crap available because they are not aimed at consumer/audiophile market. The mass market stuff has that crap because you tailor it to your customer. You don't think that a JBL 4722N theater speaker has passive bi-amping terminals do you? It can be passively done or actively done--because of market demands. Yes, a consumer can purchase those speakers for their basement--and people do but it is not consumer friendly. No gloss black, no grills--hell, the horns sits on a flat black box and you can see the crossover/input boards.
Doubling the size of something, wasting electricity, generating heat and throwing away resources to gain nothing tend to go against my way of thinking. Even if cost did not matter, designing something that is horrifically wasteful just to avoid doing it right I really don't understand. It reminds me of the kids that put giant exhaust tips and big wings on their FWD econoboxes to make race cars---uhhhh, you are actually making it slower but everyone did stupid things when they were kids--you get a pass. Now when a 35 year old guy does that to their car, they are either a pedo creep or tragically ignorant--you don't get a pass when you are 35!
Now if you DO want to join the ranks of the cool kids and actually improve your sound--you can (technically) call it "active bi-amping" by using subwooers that naturally have electronic adjustable crossovers, delay and so on. Not only can you say it is "bi-amped" but also say it uses active bass management
Any pair of speakers can be improved with proper subwoofers placed, measured and spec'd properly so you won't be wasting amplifiers as they will actually improve your sound. It is very, very hard to blow up subwoofers--so you don't need to fully understand the ins ad outs of tweeter/mid protection, filter types, filter slopes, Fs of drivers, power handling and so on. So, if you want to start your active bi-amping journey without blowing stuff up, crossing subwoofers to your main woofers is your safest bet and WILL improve your sound quality, response across multiple seats and lower distortion. A great place to screw around with all sorts of settings to learn what they do without frying drivers. Edit! I do remember Blaupunkt made a "passive bi-amp" 6x9 years ago. It was a dual voice coil 6x9 woofer so you could add an amp to "increase the bass" or somehig. Uhhhh....it increased the bass, increased the mids and increased the volume of the woofer breakup modes soooo....they quit producing the thing (late 80's???) The midrange and tweeter had blocking caps on them and I think th 6x9 had a simple inductor coil high pass. It made a splash then vanished from their lineup never to show up ever again. Since it has been decades--I am assuming that thing was not copied by other manufacturers.
Just another angle of thinking--what do the professionals do when money, their job and thousands of paying patrons are thrown into the mix? It is not exact but when some audiophile thing only exists on the consumer audio side, it does call for one to ponder why. Hmmmm...
watchnerd
Grand Contributor
I'm not sure which $4k Revel bookshelf speakers you're referring to, but the TOTL bookshelf Revel Gem 2 has dual binding posts:
RealityCheck18
Member
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https://www.revelspeakers.com/produ...E-_color=Walnut-GLOBAL-Current&cgid=bookshelf
There is also the M105 that was tested--the list goes on.
I understand the draw, a manufacturer has to cast the widest net to generate the most sales--they are not a charity after all. Most of the sales for audio equipment are not to geeks and eggheads--they are not so they must be styled for the general consumer. Makes sense, you can build the ultimate gadget but if it don't sell, you go out of business.
The consumer loves glossy/shiny things--although for a HT system in a darkened room the last thing you want is something that reflects light! Still, the consumers like shiny so your off-the-shelf speakers and subs will be reflecting light and screwing up your viewing experience. Some people actually prefer their audio equipment to be subtle and not scream out "look at me!"--but plenty of "high end" speakers/audio gear is very garish and is hard to miss. You could say that overwhelming style dominates the high end market so if you are in that bracket, you are generally greated with large, weird looking, very shiny speakers and massive amps with very thick front plates with no clip/output meters or adjustable gain controls.
Revel is part of Harman--they have produced plenty of utter garbage over the years be it a $500 Oppo drive inside a fancy case, call it a Lexicon and charge six times the price. No worries, I am fully aware of who they are so tend to be even more critical of them for that reason. All audio companies portray themselves as the audio messiah--such is marketing so a given. It is fully understandable when competing in the $200 bookshelf market to have a heaping helping of fluff to hide the flaws. Once you go to the top of the range, I'd expect a more engineering focused product over the latest audio fads but even Revel has to dance to the master. I'm sure some engineers really didn't want passive bi-amp stuff on their baby, the M126Be does not contain it so a win. However, even Revel must bend to fashion because the marketing people, bean counters and all that get their fingers in the product after it leaves the lab.
I do applaud Revel for having the guts to go against audio fashion by refusing to put passive bi-amping terminals on the M126Be and the 105--good on them! They don't have the utter balls it would take to put in active bi-amping terminals and a switch though.... that would lead to disaster as some idiot would connect two full range amps up to them without a processor and nuke the tweeter in seconds. Warranty operations cost money and idiots scream the loudest so you can bet Revel bashing would sweep the boards. It don't matter that there was a warning sticker, it won't matter that the consumer did not read the book as the consumer has the right to be clueless with no personal responsibility for their actions. Trust me, I know! For that reason, you won't see active bi-amping on most consumer speakers because the manufacturer is expected to save us from ourselves.
I'm not an active processing speaker snob--I'm not! It is a tool that when needed works very well but not the only option. Sure, I can actively process my speakers and might do that in the future but at this point, the juice is not worth the squeeze. Car audio and PA active processing does wonders and can fix complex problems that passive can't. My issues with my HT tend towards room acoustics and naturally limited locations I can place speakers and subs so once that is the best I can acheive--then I'll worry about the speakers. Fully aware some acoustic panels would give far better results than actively processing my speakers--moving the speakers a foot further away from boundries would get great also. Alas, my living room is not very accomidating for proper speaker placement and neither is my wife. I tend towards fixing the biggest problems first and my measurements show I can do better. Stupid measurements!
After all, my AVR has a "double bass" function--it must be better because it is there--right? Plenty of features on consumer gear that don't improve anything, quite often they are either useless or make things worse. I don't fault the manufacturers, they have to follow the fashions to stay in business. How much did a "digital ready" sticker cost decades back to slap on speakers--I'm sure the 2 cents the sticker cost payed more than that in return on the showroom floor. As with all things you purchase, best to have at least a basic understanding of how things work and have a concept of the realities of the market place. When confused, I just ask the professional types about things be it cars, tools, audio gear or wood products as their use means a paycheck. As a mechanic told me "All brands suck. The trick is to find the one that sucks in the least in what you want it to do."
At least with ASR measurements, it is much easier to find things that suck the least although "We don't suck" would not test market well. YMMV
There is also the M105 that was tested--the list goes on.
I understand the draw, a manufacturer has to cast the widest net to generate the most sales--they are not a charity after all. Most of the sales for audio equipment are not to geeks and eggheads--they are not so they must be styled for the general consumer. Makes sense, you can build the ultimate gadget but if it don't sell, you go out of business.
The consumer loves glossy/shiny things--although for a HT system in a darkened room the last thing you want is something that reflects light! Still, the consumers like shiny so your off-the-shelf speakers and subs will be reflecting light and screwing up your viewing experience. Some people actually prefer their audio equipment to be subtle and not scream out "look at me!"--but plenty of "high end" speakers/audio gear is very garish and is hard to miss. You could say that overwhelming style dominates the high end market so if you are in that bracket, you are generally greated with large, weird looking, very shiny speakers and massive amps with very thick front plates with no clip/output meters or adjustable gain controls.
Revel is part of Harman--they have produced plenty of utter garbage over the years be it a $500 Oppo drive inside a fancy case, call it a Lexicon and charge six times the price. No worries, I am fully aware of who they are so tend to be even more critical of them for that reason. All audio companies portray themselves as the audio messiah--such is marketing so a given. It is fully understandable when competing in the $200 bookshelf market to have a heaping helping of fluff to hide the flaws. Once you go to the top of the range, I'd expect a more engineering focused product over the latest audio fads but even Revel has to dance to the master. I'm sure some engineers really didn't want passive bi-amp stuff on their baby, the M126Be does not contain it so a win. However, even Revel must bend to fashion because the marketing people, bean counters and all that get their fingers in the product after it leaves the lab.
I do applaud Revel for having the guts to go against audio fashion by refusing to put passive bi-amping terminals on the M126Be and the 105--good on them!
They don't have the utter balls it would take to put in active bi-amping terminals and a switch though.... that would lead to disaster as some idiot would connect two full range amps up to them without a processor and nuke the tweeter in seconds. Warranty operations cost money and idiots scream the loudest so you can bet Revel bashing would sweep the boards. It don't matter that there was a warning sticker, it won't matter that the consumer did not read the book as the consumer has the right to be clueless with no personal responsibility for their actions. Trust me, I know! For that reason, you won't see active bi-amping on most consumer speakers because the manufacturer is expected to save us from ourselves. I'm not an active processing speaker snob--I'm not! It is a tool that when needed works very well but not the only option. Sure, I can actively process my speakers and might do that in the future but at this point, the juice is not worth the squeeze. Car audio and PA active processing does wonders and can fix complex problems that passive can't. My issues with my HT tend towards room acoustics and naturally limited locations I can place speakers and subs so once that is the best I can acheive--then I'll worry about the speakers. Fully aware some acoustic panels would give far better results than actively processing my speakers--moving the speakers a foot further away from boundries would get great also. Alas, my living room is not very accomidating for proper speaker placement and neither is my wife. I tend towards fixing the biggest problems first and my measurements show I can do better. Stupid measurements!
After all, my AVR has a "double bass" function--it must be better because it is there--right? Plenty of features on consumer gear that don't improve anything, quite often they are either useless or make things worse. I don't fault the manufacturers, they have to follow the fashions to stay in business. How much did a "digital ready" sticker cost decades back to slap on speakers--I'm sure the 2 cents the sticker cost payed more than that in return on the showroom floor. As with all things you purchase, best to have at least a basic understanding of how things work and have a concept of the realities of the market place. When confused, I just ask the professional types about things be it cars, tools, audio gear or wood products as their use means a paycheck. As a mechanic told me "All brands suck. The trick is to find the one that sucks in the least in what you want it to do."
At least with ASR measurements, it is much easier to find things that suck the least although "We don't suck" would not test market well. YMMV
watchnerd
Grand Contributor
I do applaud Revel for having the guts to go against audio fashion by refusing to put passive bi-amping terminals on the M126Be and the 105--good on them!
I don't think it's a matter of guts, as they kept dual binding posts on the floor standing models upline from the M126/105.
The Performa Be towers still have bi-amp/bi-wire posts.
valerianf
Addicted to Fun and Learning
"The Performa Be towers still have bi-amp/bi-wire posts."
It is very easy to explain why: larger is the bass speaker, higher is the number of bass speakers, stronger will be the back EMF. Large tower speakers well designed should have a bi-amp capability.
It is very easy to explain why: larger is the bass speaker, higher is the number of bass speakers, stronger will be the back EMF. Large tower speakers well designed should have a bi-amp capability.
watchnerd
Grand Contributor
And yet so many other manufacturers that have big tower speakers aren't bi-amp ready.
Why?
Because it doesn't really matter.
watchnerd
Grand Contributor
Vini darko
Major Contributor
I run my speakers passive bi-amp'd.
My amps are very similar pioneer mj200 / mj300. They are both rated for 8-16 ohm loads. My speakers are 4 ohm for one amp but when split for bi amp they are 8ohm for each amp. So I get proper impeadance matching and more overall headroom. Happy days.
My amps are very similar pioneer mj200 / mj300. They are both rated for 8-16 ohm loads. My speakers are 4 ohm for one amp but when split for bi amp they are 8ohm for each amp. So I get proper impeadance matching and more overall headroom. Happy days.
watchnerd
Grand Contributor
Did you architect it this way intentionally, or just grow into this config somewhat accidentally?
Because if your speakers are 4 ohm, one could always just have purchased a 4 ohm capable amp to begin with.
Vini darko
Major Contributor
It's just evolved that way accidentally. Wish I could claim to have a plan.
Are there any disadvantages to passive bi-amping? If a person has an AVR that is compatible with passive bi-amping, they aren't using the extra surround channels, and their front left and right speakers have two terminals for bi-amping is there any reason, other than the negligible cost of two extra cables, not to utilize the bi-amping? It doesn't seem like something that is so good as to choose one speaker or AVR other another, but if your equipment already has it available it seams to me it's like a potential upgrade for free!
Thoughts?
Thoughts?
It wastes power and increases heat with insignificant (inaudible) advantage in the vast majority of cases. And does not "double the power" to the speakers. But no, does not really hurt anything, and if the amps' output impedance is high relative to the cables and speakers may provide some isolation of HF and LF drivers. The main problem is that AVRs send the same signal to the HF and LF amps so you don't get any real headroom advantage as you would with active bi-amping.
More info: https://www.audiosciencereview.com/forum/index.php?threads/bi-amping-101.22817/#post-759521
More info: https://www.audiosciencereview.com/forum/index.php?threads/bi-amping-101.22817/#post-759521
Last edited:
I don't think I said or have even read anywhere that it "doubles the power." I was unaware it could cause more heat loss. I believe I read on audioholics that it was more power efficient because it made less use of the speakers internal passive crossovers, which lose power as heat? I guess I'd rather have more heat at the speaker than at the AVR. My understanding was that bi-amping would be potentially more efficient and create more (potentially audibly negligible, but nonetheless measurable) power for the speaker drivers?
I like your article. Maybe I'm not understanding it correctly, but in your table the standard amp created 0.031 watts where as the passive bi-amped system created 0.02 watts for the LF and 0.02 watts or the HF, which would total 0.04 watts. In that example the passive bi-amping was producing about 20% more watts, with potentially less crossover distortion?
Sorry, my answer was general, and true you did not say that. I have read over and over again how bi-amping automagically "doubles the power". Just not true the way AVRs do it. AVRs still use the internal speaker crossovers so there is still power loss there (unless you remove them and use a true active solution -- the link explains things). When you split the signal, total power goes up, because you have to deliver all the power you did before plus two amplifiers are now biased/operating/driving and they are not (in the real world) 100% efficient so there is additional waste power and thus heat in the AVR.
Check out the link -- I walked through the basic scenario in the first post, then added a couple of posts later showing a multitone example that better illustrates how "real" bi-amping helps where "passive" bi-amping that AVRs perform doesn't really.
Bi-amping is only more efficient if you can use a smaller, lower-powered amplifier for the treble where less power is required. The way AVRs do it, that is not possible, since the amps both receive the same input signal thus both need the same voltage swing.
No, the passive case delivered (required) more power, and thus produces more heat, for the exact same output from the speakers. You are spending more power for the same result. That does not really have any bearing on "crossover distortion". Crossover distortion is beyond the scope of that article; to me, it is the distortion created with low signal levels around the signal zero-crossings of the amplifier as it changes from say class A to class B operation. Speaker crossovers are passive elements and the argument is that back-EMF from the drivers interacts through the crossover, modulating the signals so the LF driver modulates the HF driver and vice-versa. If you have low enough driving impedance, i.e. amplifier output impedance plus speaker cables, then that is a non-issue. I would expect it may be an issue with tube amps, but bet it is usually inaudible. It also ignores the intermodulation of the drivers (cones) from the actual acoustic waves inside the box.
Note that the power levels are very low in those examples because I used a 1 V signal. That's what I had in my program and I didn't bother to change it. Everything is relative.
