Upgrade Path Question - Please Read

[Dougey_Jones]

As you can see in my signature, I've been using 3/4 channels of my pair of Apollon NCx500 stereo amps to power my pair of Revel F206 and C205. I recently acquired a pair of Revel F208, and would love to be able to use all four channels of my Apollon amps to Bi-Amp the F208's. That leaves me with only my Denon x3700h to power the Revel c205, which isn't the end of the world, but not ideal in my opinion.

I remember seeing a review of a Topping stereo amp that put out impressive power into 4ohms with high SINAD when bridged, does anybody know what I'm talking about? Would that be a good option to power my center channel?

Any other suggestions that you all think will fit the bill would also be welcome.

Thanks,

 

[DWPress]

If you're talking about bi-amping the 208's and keeping the internal XO there is no real benefit in doing so.

Otherwise I believe it is the Topping B-200 you are inquiring about if you intend on getting an additional amp anyway.

 

[Dougey_Jones]

If you're talking about bi-amping the 208's and keeping the internal XO there is no real benefit in doing so.

Why do people say this? People have bi-amped speakers this way for decades. Aside from it doubling the available power, isn’t there some intrinsic benefit to the power source available for each section being separate, demands from one not affecting the other, etc.

 

[DWPress]

Why do people say this?

This will answer your question:

BiAmp (Bi-Amplification - Not Quite Magic, But Close) - Part 1

ESP - The Audio Pages. How to biamp or triamp your hi-hi speaker system for greatly improved sound, and higher sound levels with less distortion.

sound-au.com

 

[Dougey_Jones]

This will answer your question:

BiAmp (Bi-Amplification - Not Quite Magic, But Close) - Part 1

ESP - The Audio Pages. How to biamp or triamp your hi-hi speaker system for greatly improved sound, and higher sound levels with less distortion.

sound-au.com

That article didn’t say anything I didn’t already know.

It also seems to delineate between removing the bridge strap between bass and mid/hi passive networks to BiAmp (what I’m talking about doing) versus deleting the passive crossover altogether, which would require three amps per speaker in my case, and a device to run the crossovers.

Got any better reasoning?

 

[DWPress]

Then you need to read it again. I assure you the science behind your question is there.

 

[LTig]

Why do people say this? People have bi-amped speakers this way for decades.

Yep.

Aside from it doubling the available power,

This is wrong. The speaker consumes the same amount of power regardless whether it is fed by one or two power amps. The individual power amp therefore emits less power in biamp mode.

isn’t there some intrinsic benefit to the power source available for each section being separate, demands from one not affecting the other, etc.

The only way biamping may sound better is when you clip the amps. In biamp mode only the woofer amp will clip so the highs are not clipped as well. I'm this case though a single amp with more power still sounds better than a clipped biamped system.

 

[kemmler3D]

isn’t there some intrinsic benefit to the power source available for each section being separate, demands from one not affecting the other, etc.

As @LTig notes, the benefit only comes in if you actually need more power than one amp channel can produce, i.e. to avoid clipping. If you aren't getting near the limits of a single amp channel then biamping is probably more trouble than it's worth.

 

[Dougey_Jones]

As @LTig notes, the benefit only comes in if you actually need more power than one amp channel can produce, i.e. to avoid clipping. If you aren't getting near the limits of a single amp channel then biamping is probably more trouble than it's worth.

We’re obviously talking about minutiae here, small benefits. But a horizontally bi-amped setup where one stereo amp handles mids/highs and the other handles lows should net some small benefits, since big transients that draw current for bass will no longer affect the mids and highs.

 

[kyuu]

You might want to look through this thread if you want to learn why passive bi-amping is mostly useless, and actually has some drawbacks. But the TL;DR is that you're much better off bridging the amp channels and using your bridged amp to power the speaker than doing a passive bi-amp. That way you're providing additional power to the woofer, which is where the vast majority of the energy needs to go, rather than having one of the amp channels dedicated to the tweeter (and mid?) where it will largely be loafing around.

This is assuming the NCx500 can be bridged. I can't seem to find any information one way or the other. Though given the power that amp has available on just one channel, there isn't really any reason not to power both speakers from a single one. My advice would just be to just set up the F208s the same way you have the F206s setup already and not have to worry about buying another amp. Otherwise, the Topping B200 as already suggested above is a nice mono option.

 

[SIY]

big transients that draw current for bass will no longer affect the mids and highs.

Within an amp's power limits, this is just not an issue.

edit: Of course, the concept of "bass transient" is not correct.

 

[JustJones]

There's a thread on bi amp not sure if you've read through it.

Bi-amping 101

This article provides a quick look at how bi-amplification works. The conventional scheme is to split the signal into two frequency bands before the power amplifiers that drive the speakers. The bass (LF) amp sees only LF signals and drives only the LF driver (woofer). The treble (HF) amp sees...

audiosciencereview.com

Edit: see above already linked by kyuu.

 

[antcollinet]

since big transients that draw current for bass will no longer affect the mids and highs

Except that they don't without bi-amping either - assuming the amp doesn't go into clipping.

EG if you have a signal which is 50Hz at 10V, and (say) 5Khz at 0.5V, the current at 50Hz might cause a voltage drop in the amp output + speaker wire impedance at 50Hz, but that will have no impact on the current at 5kHz and the corresponding voltage drop at 5kHz.

To put it another way - when you do the circuit analysis with a non sinusoidal waveform, you use a Fourier series of the waveform, and calculate each component (frequency) of the Fourier series separately. The result is the sum of the values for each individual component. The current/voltage across an impedance from one component (frequency) doesn't impact the current/voltage across that impedance for another component (frequency)

 

[Blumlein 88]

Also even if you get double power that is 3 db. Are you clipping amps now? If not, you don't need that 3 db, in fact won't use that 3 db. It is possible running 3 db lower the distortion is lower, but there is a high probability it will still be well below audible levels with music.

Here is an idea just to try it out. Use one channel for the left, one for center, bi-amp the right channel. See if you can tell a difference.

 

[Chrispy]

The center channel may actually need the most power, tho. I'd continue without the passive bi-amping, which is largely a waste of wire and is mostly based on silly audiophilia.

 

[Mr. Widget]

People have bi-amped speakers this way for decades. Aside from it doubling the available power, isn’t there some intrinsic benefit to the power source available for each section being separate, demands from one not affecting the other, etc.

As others have said in this thread, your "improvement" from bi-amping in your scenario is likely inaudibly small if at all.

Yes, people have bi-amped since the early days of multi-driver loudspeakers. Typically you bi-amp, or tri-amp, quad-amp etc. to get rid of the power robbing and distortion prone passive network used in most multi-way loudspeakers. In your case, you will continue to use the internal passive networks so the benefit if any is likely a rounding error.

 

[Chrispy]

Also somewhat shows where the "mainstream" audio info falls short of fact.....

 

[Fledermaus]

In my audiophile days, I had put together this kind of passive bi-amp once. Apart the irrational satisfaction of a goofily unique set-up, essential objective benefit was that it provided for a basic tone control : since one of the amps had its own gain control, I could fine tune the low-high balance to my liking.
Problem long solved since, thanks to DSP, which I'd recommend in case the issue was that of solving tonal balance. Otherwise, with passive X-over, powerful enough is powerful enough, don't have to bother multiplying amps and cables.

 

[Golfx]

I read a great analogy—with passive bi-amping you are just moving the jumper from the back of the speaker and essentially moving it to the back of amplifier.