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Post by Boomzilla on Aug 21, 2022 15:43:29 GMT -5
I've got two stereo power amplifiers (four independent channels). I've got speakers that are bi-amp capable (one pair of terminals for the woofer, another pair for the tweeter).
Assuming that all amplifier channels are to be used, the options seem to be:
Amp 1 = R+L bass
Amp 2 = R+L treble
or
Amp 1 = R bass + R treble
Amp 2 = L bass + L treble
Are there advantages / disadvantages to either of these options?
Factoids that may affect answers:
At no time will this setup be played loudly
The speakers are 6-ohm models with no low impedance dips
The amplifiers are "pro" models with 2-ohm stability
Both amps have 10x the power reserve that they'll need in either hookup option
Balanced XLR cables will feed the amps to minimize noise
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Post by AudioHTIT on Aug 21, 2022 15:52:49 GMT -5
I prefer the second option which is known as Vertical Bi-Amping. It allows you to place the stereo amp close to the speaker, giving it a 'monoblock' advantage (short speaker cables), and it balances the high / low load on each power supply.
Edit: Vertical Bi-Amping REQUIRES that both stereo amps be identical.
Option 1, Horizontal Bi-Amping, can be advantages if you choose two different stereo amps and optimize each for it's advantages in reproducing highs or lows. If the amps are identical, the one handling the bass will probably be working harder.
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Post by audiobill on Aug 22, 2022 6:35:00 GMT -5
First option may have less separation between channels and the treble amp will hardly be loaded where the bass amp will do all the hard work. Agree with AudioHTIT.
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Post by 405x5 on Aug 22, 2022 8:43:38 GMT -5
43 years ago……That was my first run-in with the “Bi amplification dilemma” (some may not know what an old story this is…).
My first encounter with this involved my favorite pair of stereo loudspeakers being offered updated with biamping capability.
Nothing more than a case of keeping up with the Jones’.
Fast forward to loads of folks testing the waters in all manner of configuration.
The general consensus…..it doesn’t do Jack, (even if you stand on your head.)
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KeithL
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Post by KeithL on Aug 22, 2022 11:27:09 GMT -5
To be honest, considering all of your "conditions", including that "the system will not be played loudly", and the amps will have no difficulty driving the load, I cannot imagine any difference either way.
If you exclude overall power, and the ability to play loudly without clipping peaks, there is not benefit whatsoever to bi-amping.
(And, if the amps have fans that run continuously, I would probably just use one, and so minimize the fan noise.)
FIRST OFF I AM ASSUMING THAT YOU'RE TALKING ABOUT "VERTICAL BI-AMPLIFICATION" AND NOT *TRUE* BI-AMPLIFICATION...
(You're keeping the crossovers in the speakers and NOT putting an active crossover before the amps.)
IF THE AMPLIFIERS ARE NOT ABSOLUTELY IDENTICAL then I would use one amp for the bass for both channels and one amp for the treble for both channels. (Even if the amps are "more or less the same", unless they are identical, there could be sonic differences that would be noticeable, so I would want to preserve left/right symmetry.) HOWEVER, ASSUMING THAT THE AMPLIFIERS ARE ABSOLUTELY IDENTICAL, then I would use one amplifier for both halves of each speaker. 1. In general, on average, a lot more power is used for bass than treble. Therefore this would divide the power usage equally between the amps. 2. This would let you put each amp next to the speaker it serves if you want to. (I don't consider this significant but it couldn't hurt.) 3. This would make cabling simpler.... one interconnect going to each amp and one splitter right at the amp's inputs. (Again, not significant to me, but it couldn't hurt... and would be especially better if you also choose option #2.) I've got two stereo power amplifiers (four independent channels). I've got speakers that are bi-amp capable (one pair of terminals for the woofer, another pair for the tweeter). Assuming that all amplifier channels are to be used, the options seem to be: Amp 1 = R+L bass Amp 2 = R+L treble or Amp 1 = R bass + R treble Amp 2 = L bass + L treble Are there advantages / disadvantages to either of these options? Factoids that may affect answers: At no time will this setup be played loudly The speakers are 6-ohm models with no low impedance dips The amplifiers are "pro" models with 2-ohm stability Both amps have 10x the power reserve that they'll need in either hookup option Balanced XLR cables will feed the amps to minimize noise
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KeithL
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Post by KeithL on Aug 22, 2022 11:41:06 GMT -5
That has been my experience. REAL bi-amping, where the passive crossovers in the speakers are eliminated, and replaced with an active crossover before the amplifiers, has several benefits. Like better amplifier control of the drivers due to improved damping, and being able to use a more complex line level crossover, which offers you better EQ options, without compromising efficiency and damping. (This is the benefit of actual bi-amped powered speakers as well as separate components that are truly bi-amped - when used at normal listening levels.) This is all in addition to the obvious benefit of preventing distortion from affecting the midrange and tweeter if you clip the bass channel. This is a significant issue in live concerts, where speakers are played very loudly, and headroom is often at a premium, so there is a real threat of peak clipping. (The "partitioning of the effects of distortion" works both ways... but the bass channel is more likely to be clipped and clipping is more audible in the midrange channel.) However, at best, "vertical bi-amping" has a slight benefit if you have low powered amps, and inefficient speakers, and like to play things really loud... (But I've never honestly noticed any specific improvement by doing it.) Note that, in the past, there were one or two speakers that offered a true bi-amping option, including a switch that actually COULD bypass the passive crossover in the speaker. (I had a pair of really old Vandersteens that offered this - as well as an optional active line level crossover to go with them if that option was chosen.) And, while I'm sure some pro gear still offers that option, I don't know of any home speakers that do. 43 years ago……That was my first run-in with the “Bi amplification dilemma” (some may not know what an old story this is…). My first encounter with this involved my favorite pair of stereo loudspeakers being offered updated with biamping capability. Nothing more than a case of keeping up with the Jones’. Fast forward to loads of folks testing the waters in all manner of configuration. The general consensus…..it doesn’t do Jack, (even if you stand on your head.) |
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Post by Boomzilla on Aug 22, 2022 13:14:58 GMT -5
Yes, the amplifiers are identical - same make & model. Yes, I understand that the usual purpose of biamplification is to provide more power (that I don't need). Yes, I'm talking about vertical biamplification (the crossovers are in the speakers, not electronic & upstream). The only reason I'm even considering it is that I just happen to have the two identical stereo power amps (bought them at a yard sale - used to power a church PA system). Despite the fact that these were originally "pro" amps, they sound as good as anything else I've got. The circuitry is a copy of Leach amplifiers. The units are AB Precedent Series 600LX models: 2x270 WPC @ 8 Ohms 2x425 WPC @ 4 Ohms 1x750 W @ 8 Ohms (bridged mono) XLR / ¼" phone jack inputs 5-way binding post outputs 19" rack mount @ 30# |
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Post by AudioHTIT on Aug 22, 2022 13:27:40 GMT -5
… The only reason I'm even considering it is that I just happen to have the two identical stereo power amps … That’s as good a reason as any, I’m currently bi-amping with (4) DC-1s because … I have them. It does bring up the question as to what you call bi-amping with identical monoblocks? Is it vertical? … yes, is it horizontal? … yes. How about “Diagonal”? |
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Post by Boomzilla on Aug 22, 2022 13:40:24 GMT -5
Monogonal??
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Post by 405x5 on Aug 22, 2022 14:33:19 GMT -5
“bought them at a yard sale - used to power a church” Well then….for sure it will sound HEAVENLY |
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KeithL
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Post by KeithL on Aug 22, 2022 14:45:59 GMT -5
I would just stick with the general term - "passive bi-amping" (to differentiate it from real bi-amping - with an active crossover and the amps connected directly to the drivers). … The only reason I'm even considering it is that I just happen to have the two identical stereo power amps … That’s as good a reason as any, I’m currently bi-amping with (4) DC-1s because … I have them. It does bring up the question as to what you call bi-amping with identical monoblocks? Is it vertical? … yes, is it horizontal? … yes. How about “Diagonal”? |
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DYohn
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Posts: 18,351
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Post by DYohn on Aug 22, 2022 17:47:11 GMT -5
The only legitimate reason to bi-amp is for maximum dbSPL. It is useful for live sound, for car audio competition, and for a DJ or nightclub. For a home user, "Bi-amp" is exactly like 'Bi-wire." You get to "buy" more amps or wires.
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Post by thompson12 on Aug 22, 2022 20:01:25 GMT -5
Mitch
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Post by 405x5 on Aug 23, 2022 7:00:54 GMT -5
I don’t hear enough discussion about subwoofer integration under the SAME topic as biamping.
When a powered sub. is delivering the goods on the same channel as your main amplifier you ARE “biamping” but perhaps not thinking?
Properly configured, that subwoofer is taking a significant load off the main amp. and reducing the stress on the main speakers.
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KeithL
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Post by KeithL on Aug 23, 2022 9:15:25 GMT -5
Subwoofers are generally considered to be a whole separate topic - and are generally considered to be part of "bass management". (When subwoofers came into vogue "bi-wiring" was generally a term used for actual bi-amped systems with active crossovers.) At that point, systems that consisted of "satellites and subs" were not generally described as "bi-amped". It's also worth noting that the benefits of using a separate subwoofer are NOT normally specifically attributed to normal bi-amped systems either. Nowadays the term bi-amping is generally only used to discuss crossovers at higher frequencies. (Although, of course, technically bass management is true bi-amping, whereas what they call "passive bi-amping" really is not.) (If you look at professional stage gear, which is often bi-amped, or even tri-amped, the term "subwoofer" isn't used much... it's just "bass bins that cover different frequency ranges"...) I am personally of the opinion that "passive bi-amping" was never really a worthwhile feature. It probably started out as "a way to get some use out of those extra amplifier channels"... So "something you could do with the extra channels on a 5.1 system if you were running stereo"... Or "something you can do with the extra two channels if you have a 7.1 channel system and you're running 5.1"... (Although it made somewhat more sense when low-powered amplifiers and AVRs were more the norm...) And I suppose that, from a marketing perspective, it appealed to some people who confused it with "real professional bi-amped speakers"... And, from the point of view of the speaker, "passive bi-amp capability" is a trivial "feature" to add... There's no real internal rewiring; you're simply adding an extra pair of binding posts. The "bi-wiring jumper" is simply a connection between two parts of a normal crossover that would otherwise be made inside. (And those pretty little metal jumpers are actually easier to put on during assembly than a six inch piece of wire.) I don’t hear enough discussion about subwoofer integration under the SAME topic as biamping. When a powered sub. is delivering the goods on the same channel as your main amplifier you ARE “biamping” but perhaps not thinking? Properly configured, that subwoofer is taking a significant load off the main amp. and reducing the stress on the main speakers. |
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