How do I bi-amp?

danlarson

I have a (new) pair of RTi A9 speakers and an Emotiva XPA-5 amp that is coming this week. How do I bi-amp the speakers? I have pre-amp outs from my Harmon Kardon reciever that I will run to the XPA-- do I need to split the RCA?

Any tips/pointers/articles/links on how to bi-amp, especially with these speakers, would be great. (I know to remove the plating that links the speaker inputs-- I'm fuzzy on how to go from the receiver though.)

comfortablycurt

I'm not to knowledgeable on it myself, this is a good article on the subject that I found a while back though. It's a long read...but it has a lot of info. I'm sure someone that knows more about it will be able to chime in more than me.

From what I've understood though, using the two separate pairs of binding posts on the back of your speakers isn't true bi-amping. It's similar, but not quite the same. True bi-amping involves a separate external crossover for each speaker.

http://sound.westhost.com/bi-amp.htm

danlarson

Anyone got recommendations for crossovers in a reasonable price range-- that would go well with the RTi A9s and the XPA-5, with my Harmon Kardon 384 receiver?

comfortablycurt

I have another question actually that kinda fits into the same topic. I don't wanna start a whole new thread for it though.

Is there such a thing as Tri-amping? If you have a 3 way speaker, you have three different driver sizes typically. Wouldn't it be better to have a separate crossover for each driver, with a dedicated amp for the woofers, mids and tweeters?

mmadden28

danlarson wrote: »

I have a (new) pair of RTi A9 speakers and an Emotiva XPA-5 amp that is coming this week. How do I bi-amp the speakers? I have pre-amp outs from my Harmon Kardon reciever that I will run to the XPA-- do I need to split the RCA?

Any tips/pointers/articles/links on how to bi-amp, especially with these speakers, would be great. (I know to remove the plating that links the speaker inputs-- I'm fuzzy on how to go from the receiver though.)

If we disregard for a moment what is said in that article--I only just skimmed over the article and what I gathered is that using an external crossover network might be a better and more efficient way to do it, but I don't see how the author can say using two amps is not true biamping. Of course I am not an expert and what the author stated could be actually true. But for the purposes that most people understand the term bi-amping to mean especially with the purpose being for Home Theater use..
Of course I'd love to learn a bit more about using an external crossover with my 2 ch. music rig....

Anyway...the way I always understood bi-amping and true bi-amping is that some AVRs allow you to use the rear channels to use for bi-amping. However an AVR typically only has one power supply. While there may be some sonic benefits realized in bi-amping this way, it's not true bi-amping when you're using, what is essentially, one amp.

Using two amps would be true bi-amping.

Removing the jumpers enables the bi-amping in the speakers. The speaker has its own crossovers to filter and route the signals appropriatley.

You just split the pre-out signal from the AVR with a cable such as this. Run one line to one channel on the amp (lets say #1), and the other to another (lets say #2), then you run the amp speaker level outputs from #1 to lets say the Left channels lower binding posts, and channel #2's to the upper posts. You do a similar thing for the Right channel with lets say channels #4 and #5.

comfortablycurt

I'm in no way a bi-amping expert. I've never even bi-amped anything before, but I'd have to agree. I don't really see what the difference is between the internal crossovers that a lot of speakers have, and external crossovers that you can buy separately. A crossover is a crossover...granted I'm sure there are good ones and bad ones, but they essentially all do the same thing.

Especially when you're buying from a good brand like Polk, I don't see why you'd really need an external crossover, when there is already an internal one which is there for the purpose of bi-amping.

Dagoods

I am Bi-amping all of my speakers and before I did I talked to Polk customer service. They said that the internal crossover was fine to use. That the best was to do it was "vertical Bi-amping". That means using a 2 channel amp to each speaker to be bi-amped. Use Left channel for highs and right channel for lows. So each speaker has it's own dedicated amp. Same as not Bi-amping and using mono blocks in my opinion.

The guy at Polk freaked at the thought of disabling the internal crossover and using an external one. Said that on a three way speaker you would need 3 crossovers and three amps. It can be done but complicated and some say it is the only "true" way to Bi-amp. To each his own but I think that the crossover in the Polks is a very good one and can do the job in a home theater environment. If I were doing a commercial theater of course it would have external crossovers.

I think anytime you add external amps you make am improvement in sound. It also takes the burden off the AVR.

I had a Yamaha amp from my 2 channel days and started buying more of them on Ebay over the last few months and here is what I have ended up with. Each speaker has it's own amp and I got them for an average of $200.00 each on Ebay. You can find some really good deals if you watch and are careful.

RTi10's = Yamaha MX 800 (2X175 W)
RTiA1's = Yamaha MX 600 (2X135 W)
CSi5 = Yamaha M60 (2X160 W)

The external amps really woke up the speakers with the additional power even if I saw no improvement with Bi-amping or not Bi-amping.

There is a lot of discussion on the pros and cons of Bi-amping. I say to each his own and enjoy you hobby. That's why we do it and every one's system and opinion is different. It makes this all the more interesting.

mewisemagic

off topic,but i would like to know how you like the emotiva once you get it up and running

danlarson

My purpose of bi-amping would be to throw more juice at the mains-- throwing 2 amp modules at each main, 1 amp module at the center-- and letting the AVR drive the surrounds. But, without bi-amping, the 5 amp modules will drive the mains and center equally (1/3 of the watts per channel), which will also be killer.

Regarding the crossover-- you wouldn't want to disable the speaker crossovers ever-- but I would think you'd get better sound if you crossover before the amp-- so you're not amplifying the bass for the mid/high speakers and vise-versa. Although, that's just my theory, I'm not sure how it works.

Regarding the XPA-5-- yeah, I'll post when it gets here-- it just left Nashville (I'm in Denver). I can't freaking wait-- those A9s are going to get born again. (Shoot, I'm still driving them off my 75 watt Harmon Kardon!)

SEH

comfortably_cur wrote: »

Is there such a thing as Tri-amping?

Yes. In car audio active crossovers and multiple amps are very common. And actually, if somebody's bi-amping their speakers in a .1 system, then they already are tri-amping. Sub has its own power, and the typical AVR has the ability to do an active two-way crossover. Or maybe that's just bi-amping, depending on how you define it.

If you have a 3 way speaker, you have three different driver sizes typically. Wouldn't it be better to have a separate crossover for each driver, with a dedicated amp for the woofers, mids and tweeters?

I guess that would depend on whether you think it's better to have a separate amp to run tweeters (which I guess is a given if you prefer to bi-amp two-ways), and how good your active crossovers ended up working for you. My bet is that for the price of an active three-way crossover you could just get an amp with power to waste, wire it up the normal way, use the crossovers the manufacturer gave you, and be more than happy.

fossy

Looking forward to hearing how the 9's sound with some good power to um. I really want to get a pair but must wait till i pay off some bills.I have a pair of parasound hca 1000's to run mono when I get a pair.

danlarson

I would recommend the polk direct ebay store-- I got my 9s from Amazon, but got my center channel (csia6) and surrounds (fxia4) from there refurb, and couldn't tell the difference between refurb and new. And it's a ton cheaper.