Bi-Amping

[jedinite24]

Here is a great reply from the one and only dyohn from a seperate thread. Great stuff imo.

Re: bi-amping???
« Reply #5 Today at 12:30pm »

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Q: Should I bi-amp my speakers?

Answer from a typical amplifier manufacturer: Yes, please, bi-amp everything! Heck, tri-amp it! Buy more amps!

Answer from a typical self-proclaimed audiophile: Yes, you must at least bi-amp and bi-wire as the increased intensity from multiple signal pathways adds sparkle and air and removes many veils, plus you get rid of that nasty, evil, energy-stealing passive crossover. Plus if the speaker is not designed to be bi-amped it is not a real speaker in the first place.

Answer from a typical power-mad bass-head: Biamp! Biamp! More power!! More Boom!! More woofers!! More pretty lights!!! AHHHHH!!!!

Answer from a typical audio engineer: It's not genuine bi-amping unless an external active crossover is implemented. Bi-amping can have some benefits in some applications as headroom and damping factor are increased as is amplifier K factor since net impedance is generally greater, plus it gives the user total control over crossover points and slopes so the loudspeaker system can be customized to better integrate with the listening environment.

Answer from a typical regular person: What's that mean?

Answer from a typical enthusiast: If you want to do it, do it. If you hear an improvement in your system, great. If you don't, you can always sell the extra amp. But you're cheating yourself if you never try it.

My answer: Whatever floats yer boat.

Here are some helpful basic diagrams provided by fellow Emoholic: taoggniklat

[handree]

Nice pictures. I've just ordered a Marchand Elec kit to build my own
electronic cross-over. I said this before the product that is missing
from the market is a high end pre-amp that does the cross-over
in the digital domain. If you look at most of the pro equipment
the noise level is not so great (about 90 db). The signal
has to go though many op-amps or an extra AD conversion.

I would love a pre amp that has multiple high end DACs so that
the crossover is build in. Volume control should be processed
after the frequency split. The only units that do this are >$4k.

www.deqx.com/products.php

Maybe another product for Emotiva to compete with.

[Nemesis.ie]

Maybe Emotiva can add that to the "uber processor" above the XMC-1.

[handree]

Actually. I just checked the DEQX. It does not mention Dolby DTS
etc. Ideally the processor should first decode the digital. Then
do the cross-over and finally volume control. I use 2 speaker stereo.
However another feature would be to be able to add other boxes
to decode the remaining channels.

I think this product is a long way off. So for the next couple of
years I will go analog. Waiting for somebody to come up with this
product.

I though about designing/building my own. The Dolby decoder
chips are not available without expensive licenses. They are only
a few dollars each but the DIY's can't get them.

I think the rest is pretty straight forward. FPGA's and simple
24 dB LR filtering, volume adjustment. Emotiva already has
room correction equalization. Then add a few high-end DAC
chips and a quality analogue circuit and your done.

This product would also boost the sale of the XPA multi channel
amps as you now need many more power beasts
In theory with this product you should be able to design
the best stereo, period!

[Deleted]

Jan 1, 2010 12:46:52 GMT -5 Nemesis.ie said:

Maybe Emotiva can add that to the "uber processor" above the XMC-1.

they had talked about it once but my guess is that planned is scrapped or at best put on hold until they sort out the UMC release.

[Nemesis.ie]

Once the UMC and XMC are done and shipping they can presumably take a look at the next one.

[handree]

I hope so. This type of device does not exist.
Only Meridian does something similar in their
speakers. But this is all proprietary. I bet
you could sell 1000's of these.

In order to really tune the speakers you need
to be able to adjust: Cross-over points,
delays between the drivers, volume
of each drivers, possible notch filters,
room correction. If you want to accomplish
this with op-amps you will have possibly 8-10
more opamps in the signal path. Digital
cross-overs allow this, but take in analog
signals. Even if they have digital in they
do not have a dolby decoder so they can't
be used for home theater.

So maybe this device could be an add on to the
UMC-1? It could use the digital out of any preamp.
Then do the cross-over and volume.

Maybe a digital cross-over for the home market
with a Dolby-DTS decoder chip would solve
the problem. I would like the pre-amp to control
the volume levels of each of the decoders.

[RadTech]

That would be sweet!

[handree]

I tri-amped my speakers with the 2 XPA-3s a few weeks ago. I used the
Marchand Electronics Kit XM-9 de luxe 3 ways. It sounds very good but I
can hear some noise with my ears again the speakers. I still think
a fully digital solution with the DACs at the last possible points would
be the ultimate solution. Just hope that someone will make
this happen one day.

[jedinite24]

Another pic of bi-amping from taoggniklat

[Animo]

Mar 1, 2010 22:43:11 GMT -5 jedinite24 said:

Another pic of bi-amping from taoggniklat

Again as before, this is a picture of Bi-wiring.
There is no active crossover between the amp and the speakers.

[Stevens]

Aug 23, 2010 14:07:16 GMT -5 Animo said:

Again as before, this is a picture of Bi-wiring.
There is no active crossover between the amp and the speakers.

No, this is what is commonly known as passive bi-amping. It is not the same as bi-wiring, nor is it the same as active bi-amping, which I think is what Animo refers to.

[Mr. Ben]

Bi-wiring:





Bi-Amping:



Passive biamping uses a Y-cable to link a single preamp to both amplifier inputs. Active biamping takes the crossovers out of the speakers (speaker surgery), and puts new crossovers in front of the amplifiers, so that each amplifier is only receiving a portion of the audio signal.

[NorthStar]

^ Alright, great post above from Mr. Ben.

* Now we all know that in order to Bi-Wire or Bi-Amp, you need two sets of binding posts in the back of your loudspeakers. And so as Tri-Wire or Tri-Amp, you need three sets of those. [Talking about Passive Bi-Amping or Tri-Amping here.]

** Now, about 'Bridging' speakers for people that have big towers loudpeakers and that are power (current) hungry, with low bass extension capability, but that have only ONE set of binding posts in the back?
{And we all now that you only use the Positive (+) speaker wires when Bridging, and you don't use at all the Negative (-) speaker wires, coming from the two amplifier channels of your power amp or receiver, per each speaker.}

Thank you!

P.S. Some manufacturers caution that in order to Bridge from their amps, you need speakers with an impedance of 8 Ohms or higher. If failing to do so, you are risking to severely damage the internal amplifiers!
By the way, they even caution the same when Bi-Amping (8 Ohms impedance or higher for the speakers).

[Erwin.BE]

This topic looks more like UFAQ: unfrequently asked questions...

The Lyngdorf DPA-1 lets you bi-amp. It has active digital crossovers. I am not savvy about all the possibilities of this thing, but the crossover can be chosen between 40 - 99,999 Hz. Here's the manual, the info is on p29.

www.lyngdorf.com/images/stories/Download/Manuals/DPA-1%2001-08-09.pdf

BTW this thing costs €3,000 (think $5,000 USD)

My Jamo's can be actively bi-amped but I am not sure the benefit would be worth it. These are three-ways and the bi-amping only removes the mid/high crossover, not the low/mid. I think this is because the upper bass is (passively) attenuated in this (boxless) design.

[action]

If "Passive Bi-amping" is not beneficial, why do manufacturers even bother placing two sets of binding posts on the back? If you have two mono blocks, one mono block connected to each pair of binding posts, whould this not give more power than a single mono block connected bridged?

[NorthStar]

^ Some speaker's manufacturers have speakers with two sets of binding posts for Bi-Amping their speakers one year, and then the next they remove one set of those binding posts (from the exact same speakers) because they said they made a mistake and their speakers were not in fact recommended for Bi-Amping!!!

____________________________

Passive Bi-Amping; is it beneficial or not?
Are speakers' manufacturers honest when they say that "Passive bi-amping PROVIDES a DRAMATIC IMPROVEMENT in clarity, openness and detail with much better bass solidity and definition"?
* Of course, they also recommend that if you're using different amplifiers to make sure to use amplifiers with identical gain.

____________________________

"Bi-wiring CAN improve clarity and openness, and provide more solidity to the bass. As it only requires two additional speaker cables, it is also a low cost way to achieve even better performance from your loudspeakers".
Hmmm... About simply use thicker speaker cables?

____________________________

Bridging? ...Anyone likes to shed the proper lights on this, with accuracy please? TY

____________________________

Now, the big question: If you have some speakers with indeed two sets of binding posts in the back, and it DOES NOT say which one is which one; how do you know for sure which set is for which driver? ...By assumption?
- I know for a fact that some speakers use the top set of binding posts to power the tweeter, and the lower set for the woofers.
- But I also know that some other speakers are the exact opposite!!! ...The top set is for the woofers, and the lower set for the tweeter!

Soooooooooo; How do you know for sure, when it is NOT indicated and in the back of the speaker itself and in the speaker manual (that is if there is a manual to begin with)?

____________________________

Why does life has to be so complicated? ...Active, Passive, same Gain, ...
Is there Simplicity in this world? ...Or does it have to do with different classes of people? ...Like the Rich and the Poor? Or the educated knowlegeable ones and the uneducated unknowledgeable ones?

____________________________

Should I feel safe trusting others, or should I only trust myself from my own experience of true "Try and Learn", with all the risks involved and attached to it?

****************

Good luck trying to help me out!
...By the way, I am serious. ...All my questions are honest and legitimate.
I've been looking for true answers in the last 40 years or so!

NOTE -> An important thing here, if you do try to give me some definitive answers to my questions; please give concrete examples by enumerating the amplifiers or receivers' brands and model's numbers, plus the same for the speakers (brand & model's #). ...And also the gauge (AWG) of the speaker cable(s); in a single mono-amp, bi-amp, or tri-amp configuration.
No hocus-pocus presumptions here. ...Only real world applications with true focus.

[granteedev]

Even if they have digital in they
do not have a dolby decoder so they can't
be used for home theater.

It has an excellent ADC/DAC stage. You can use analog processor pre-outs to the the DEQX. It will even take/send a balanced connection if you specify that when you order.

a DEQX HDP-Express with a calibration kit would run a person anywhere from 2300 to 3000 but i think it's the most worthwhile investment a person can make into Hi-Fi. I'd do it for the mains alone for the way it finds the right crossover point, gives you awesome high order yet time/phase aligned crossover slopes (48db/octave as well as Finite Impulse Response (starts 1st order and can get as high as 300db/octave). Passive crossovers can not do this, plain and simple.

Pair it with a a UPA-2(tweeters where there isn't much dynamic content), XPA-2s (mids where there's lots of dynamic content) and two XPA-1s (woofers where there's even more dynamic content) @_@ and you've got the best 2 channel front stage out there!

There's also something cheaper like a Behringer DCX2496. You have to do the active crossover yourself (no auto mic setup) but it can still give better results than all the issues with passive crossovers (especially in 3-way speakers).

I'd love if emotiva came out with an actively bi- or tri-amped speaker.

Even looking at the ERT-8.3 it's got one of the most impressive (and ridiculously tidy) passive crossover designs I've ever seen but you still experience some of the drawbacks from passive crossovers - passive baffle step compensation for example can only reduce sensitivity, same with passive tweeter and mid control. So you have a speaker that may actually be 93 or 94db sensitive. You would only save on your electicity bill with that extra 3-5db of sensitivity (which is probably even more efficiency into a 4 ohm load).

I personally like the idea of paying for some quality opamps instead of pricey heavy gauge air core inductors.