Talk to me about Biamping?

[cmb3366]

OK, in my search for sonic perfection, I've been auditioning some fancier speakers. All of them have on thing in common, double binding posts with a brass strap to make them easily biampable.

This is where I get confused, what is the proper way to biamp a system. Should you buy one of those electronic crossovers and set your crossover points after the preamp, but before the poweramp, and disconnect the crossovers in the speakers? Should you just get some splitters off you preamp, run through 2 poweramps, and let the speaker crossovers do the job?

Can you use two dissimilar amps, ohhh say a Mc 2100 for the highs and a Crown PS200 for the lows? Should you use the same brand/type of amplifier?

If I should look into an 'active crossover' what is a good one, all I can find on google is lowgrade NADY and obscure progear priced around 100? Will such an inexpensive crossover do a good job?

As you can see, I really dont know which direction I should be heading in, so some council on the topic would be appreciated.

[markus]

In my opinion, a 'Bi-amped' speaker is not necessarily better than a speaker with just a bigger amp. .. there are still passive crossover components eating up 'sonic energy' i.e. VOLTAGE, dissipated as HEAT, sooooooo. . . I never bother.

You are however on the right track with using an active crossover - this makes the speaker / amplifier interface MUCH more efficient, since the frequency separation happens before the signal is amplified. This is EXACTLY the reason why 99% of aftermarket car audio systems use an active crossover between a subwoofer and the 'main' speakers . . . same thing for home theater . . .

currently, I use an active crossover to split the sound between my Karlson 15's (100 Hz and under), and my open baffle line arrays . . . never looked back using THAT setup, but I'm also a sucker for vintage bookshelf speakers, and single fullrange drivers (no crossover / maximum simplicity)

[Fred Sanford]

There are different approaches to this between different speaker models & brands.

Some have switches to switch between internal and external crossovers, some don't.

Some with the switches leave parts of the crossovers in line, some don't.

Some with no switches sound better as soon as you throw the gold straps in the garbage and use cable jumpers instead.

Yes, you can use different power amp models & types between highs & lows, absolutely. Experimenting is part of the fun, as long as you don't ever accidently send low freqs to the high drivers...that's not so fun. Which is why many speakers leave the passive crossovers in line even when you bi-amp...which brings us right back to the beginning.

DBX has a decent looking x-over for $150-170, I just played with one tonight & will check it out more thoroughly soon. Ashly also has some pretty cheap. You'll likely want one with unbalanced ins & outs, and you should also be checking for matching input & output levels to the rest of your gear.

je, just getting back home from teaching a band how to bi-amp their PA system...

[beemer]

Markus' advice is on the money. However in his case the active crossover is the only crossover, there are no passives on his speakers.

Keep in mind even if you biamp and actively cross the line level prior to the amps, the speaker's own passive xovers are still in the loop unless there is some way of disabling them. If all you have is jumpers between the two pair of binding posts then those passive xovers are still active. This really won't help you.

Your money may be better spent on an amplifier or preamp upgrade.

Best,

Paul :thmbsp:

[dgwojo]

I'm still waiting to get tube amps for this unit but I went with the BBE DS26, with MSN cashback tonight (20%), you could get into a unit like this on "that auction site" for a buck eighty eight ($188), that's about half the normal going rate for this model. I plan to use a 40 watt tube amp for the woofs, and an 8 watt tube amp for the horns on my Altecs, Dave.

Bargain BBE DS26 (http://cgi.ebay.com/BBE-DS26-LOUDSPEAKER-MANAGEMENT-SYS-2-IN-6-OUT-NEW_W0QQitemZ290241600285)

[jhal]

I am currently using a DBX 223 in my system and it is "invisible" sonically, as far as I can tell (and these speakers would let me know, loud and clearly, lol). My Yamaha preamp has no problem driving it; the input gains are at unity, as are the "high" outputs. I am sending 90hz and down to a sub, and the rest to my B&W's. I chose it because of it's capability to crossover down to 40hz, which many unit's don't go down to that low of a crossover frequency. That way, I can effectively take the sub out of the system just by turning it down to 40hz, if I choose to (for late night listening). This unit has TRS jacks, and all I did was use some TRS to RCA adapters and everything's nice and quiet. I don't have any ground loops with the satellite receiver or the bass amp, which has a 3 prong cord. Lifting the amp's signal ground was unnecessary.

I understand your application would be different, but I do recommend this unit if you are looking for a relatively low cost, high quality crossover. You can get one that has spent it's life in a fixed installation for a little over 100 bucks over there if you are patient. Everyone's going to digital loudspeaker management systems now, so quality analog gear can be found for a song. It's also available with XLR's; the DBX 223XL.

[FalconEddy]

Some of my 'big' system is bi-amped, and some of it is tri-amped. I use different seperate variable point crossover boxes. Both utilize an additional output to feed another amp for subwoofers. So, technically these full-range systems are 'tri' or 'quad' amped.

The thing with 'bi' or 'tri' amping a system is to be sure you can remove the internal crossovers in the speaker cabinets from the equation. I have switches on mine that allows me to do exactly that.

Also, you really don't need a tremendous amount of power to drive the highs. Well, at least no where nearly as much as the lows and mids.

Be sure to use proper gauge cabling that will allow enough energy to flow through them without getting hot during extend usage. In my case, 15,000+ watts will translate to a pretty fair amount of heat; so, I use 10 gauge for the mids and highs and 8 gauge for the subs. I increased the gauge cable required by one since those cables will take more physical abuse than a lighter gauge cable, and with multiple setups and breakdowns during a month, I needed something that I wasn't going to need to replace or repair every couple of months.

. . Falcon

[ALTEC9846-8A]

Tried bi amping the altecs with two tube amps. After spending $800 I couldn't hear any difference so I went back to one amplifier and the internal speaker crossovers. One thing I found out later was that the two amps must be in phase. E.G. If one amp has 5 amplification stages and the other as four,your woofer and tweeters will be out of phase(each time you amplify sound you get a 180 degree phase shift! Gets a bit scary.:yes:

[Face]

Keep it simple.

[cmb3366]

Thanks for the input guys. This morning I tried dual amping (Mac high and Onkyo low) with the passive crossovers in a pair of Klipsch RF-35's, and I've got to say, my ears like where this is going. When the Crown arrives I'm going to try it in place of the onkyo, and that will decide where I go with speakers and active crossover.

[Lux Man]

I am currently bi-amping ADS L910's. I first ran them stock, I then ran them passively bi-amped, and finally using an active cross-over. I liked them in the beginning and liked them more each step of the way. Everything continued to improve with each step. I may tri-amp them next but I would need to add another active cross-over because the one I have is a 2-way. The following link I believe is quite good.

[Lux Man]

the link I neglected to add: http://sound.westhost.com/bi-amp.htm