biamping and crossovers

[Zorac]

i have an existing set of speakers that i want to biamp. the speakers are rather power hungry and my home theater amp doesnt have enough kick for them.

the idea was to disconnect the sub from the existing crossover, and use a separate amp for the sub (with car audio electronic crossover)

ive been told that i can just disconnect a driver from a crossover, which doesn't make sense to me, as im removing a load, they should be fine right? (as i was told, it has the possibilty of reducing the impedance of the circuit to the point of possibly shorting out the amp) but im not an electronics expert, so i defer to those knowledgeable in such subjects!

the speakers in question are cerwin vega vs-150

thanks!

[Cal Weldon]

Moved to loudspeakers

[Cal Weldon]

Hi Zorac,

First off, those speakers are very efficient. One watt would be too loud for most ears. If your amp doesn't cut it, don't blame the speakers.

Second, with 3 drivers per box you might wish to consider tri-amping or you might not get what you are looking for but...

Third, I wouldn't spend a lot on those. They are a party speaker only. They are not intended for critical listening just volume.

Four, they are already balanced. Splitting off the woofer will only add bass. Not necessarily a good thing.

Sorry to tinkle on your parade but I'm not sure you're headed down the right path.

[BlueWizard]

I'm a little confused, though that is nothing new.

Are your existing speakers bi-wire/bi-amp capable?

By that I mean, are there separate connections on the back for the high and low speakers. This will usually mean FOUR speaker post connectors instead of two on each speaker, and they will be 'jumped' together with a flat strip of metal.

If your speakers are bi-wire/bi-amp capable, then the internal crossovers are already separated into Low and Mid/High sections. Remove the jumper bar, and connect one amp to the Low and another amp to the Mid/High and you are there. Simple as that.

Next, you have an AV amp, but what amp and with how many channels? (specs on the amp would save me the trouble of looking them up.)

If it is a 7.1 amp with 7 active channels, then you likely have a spare pair of amps available; assuming of course, you are running 5.1.

Personally, I suspect any problem you are having is merely a problem with the always compromised AV amp. AV amp are notorious for only delivering rated power when one channel is driven. When all channels are driven your 100watts/ch amp drops down to 30watts/ch. The problem isn't the amps themselves, it's the inability of the power supply to supply the current demand to all the amps at once.

That is, unless you have a premium AV amp that has a massive and even multiple power supplies.

It seems to me, if you insist on Surround Sound, then you simply upgrade to a massive 7 channel amp with hefty power supplies, and, assuming you have bi-wire/bi-amp capable speakers, and assuming you are running 5.1, use the extra two channels to bi-amp your speakers.

If your speakers are not bi-wire/bi-amp capable, then things get complicated and expensive. You are going to need multiple EXPENSIVE external active crossovers, and six amp channels to run them.

That's great for stereo, but I'm not sure how to correctly integrate this expensive collection into surround sound.

I would say, expect to spend $1000 to $2000 doing this right. Or you could simply spend a $1000 on a first rate 7 channel AV amp, but, again, that assumes your speakers are even bi-amp capable.

Also, keep in mind that you can't just attach random crossovers to the speakers. The crossover frequencies and slopes have been very precisely planned and executed by the manufacturer, and you need to duplicate them precisely. Also keep in mind that the internal passive crossovers may have additional components to flatten out and equalize the response. Not to mention tweaks to moderate and control the overall speaker impedance. These little tweaks would not necessarily be available to your with external active crossovers. In that case, you would need the addition of an somewhat expensive equalizer.

It is not a simple task that you are proposing. Certainly what you are proposing can be done, just expect to spend LOTS of money doing it.

Steve/bluewizard

[Zorac]

Originally posted by BlueWizard

Personally, I suspect any problem you are having is merely a problem with the always compromised AV amp. AV amp are notorious for only delivering rated power when one channel is driven. When all channels are driven your 100watts/ch amp drops down to 30watts/ch. The problem isn't the amps themselves, it's the inability of the power supply to supply the current demand to all the amps at once.

i would suspect thats my exact problem.

previously i had a yamaha m-80 powering them, and recently moved to an AV amp (instead of my previous setup where the HTPC fed directly to the amps). I needed the flexability of the AV amp (yamaha htr-6190, aka rx-v1800) and went that route.

the speakers are not bi-amp capable, which why i was hoping to simply unplug the subs, and use an electronic crossover to match the previous crossover point and power them with another amp

my home theater speakers are fairly welll matched, and i dont really want to get into starting upgrading the whole system.

i may resort to just using the preamps out and a separate stereo amp (since i have one just sitting anyway) for those two channels, but since the AV amp has the output would be nice to make use of the power aviable.

[Zorac]

Originally posted by Cal Weldon
Hi Zorac,

First off, those speakers are very efficient. One watt would be too loud for most ears. If your amp doesn't cut it, don't blame the speakers.

Second, with 3 drivers per box you might wish to consider tri-amping or you might not get what you are looking for but...

Third, I wouldn't spend a lot on those. They are a party speaker only. They are not intended for critical listening just volume.

Four, they are already balanced. Splitting off the woofer will only add bass. Not necessarily a good thing.

Sorry to tinkle on your parade but I'm not sure you're headed down the right path.

everytime i look at upgrading them, and start sampling new speakers, the price to get something that sound significantly better is out of my range, let alone the fact i would need to upgrade the amps to justify the new speakers! and after that im afraid my wife would kill me! :P

[sreten]

Originally posted by Zorac
.... the speakers are not bi-amp capable ....

Hi,

That does sound very likely, but would be true if they used a
series crossover. You could probably fairly easily add another
set of terminals. They probably did not do it because ideally
you need 3 sets of terminals and TBH CV's and tri-amping ?

/sreten.

[planet10]

We can continue to talk in generalities, what we need to get to the nitty gritty is a picture of the loudpeaker, and a picturew of the crossover,,, then we call help you sketch out the XO cirxuit and figure out wgat is doable,

One other question: what is the nominal impedance of the CVs?

dave

[Zorac]

Originally posted by sreten
[B]
That does sound very likely, but would be true if they used a
series crossover. You could probably fairly easily add another
set of terminals. They probably did not do it because ideally
you need 3 sets of terminals and TBH CV's and tri-amping ?

let me rephrase, they do not have bi-amp terminals, only a single set of terminals.

Originally posted by planet10
We can continue to talk in generalities, what we need to get to the nitty gritty is a picture of the loudpeaker, and a picturew of the crossover,,, then we call help you sketch out the XO cirxuit and figure out wgat is doable,

One other question: what is the nominal impedance of the CVs?

ill open them up and post the information shortly!

[Cal Weldon]

Here's a review

http://www.audioreview.com/mfr/cerwi...0_1594crx.aspx