I have read all great things about bi-amping as well. I'm in the same boat as you trying to figure which way to go. The fun of the idea is gone. I posted a question a little over a week ago you can check out. If I get info from some where else I'll let you know. Please contact me if you get something new. Thanks Joe
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I use bi-amping in my system to good effect. I'm using an ARC VT-100 for mids 'n tweets (Audio Artistry Dvorak) and a Carver A/V receiver for the subs. My Dvorak came with a Linkwitz-Reiley active crossover (24 db per octave) and crosses over at 100Khz. I like this setup because I can control bass volume when engineer gets stupid (play a Beck album). Also, I think this is extending the life of my insanely expensive tubes ($750.00 to retube) i.e., relieving them of bass duty. I like your idea of using a stereo amp for each channel as it's always better to keep things as "dual mono" as possible. In some cases, you can bypass the need for an external crossover if your speakers roll off enough on their own (at the crossover frequency). Let me know how things work out! -Ken
Elvin, The answers are all simple (at least in words :-) You do need to use an electronic crossover. Passive biamping is (IMHO) a complete waste of time - this is where separate amps are used to a bi-wired speaker system. If there are any gains at all, they are slight. The speaker's internal crossover from bass to mid+high must be disconnected, but keep the mid to high crossover, since that is still needed. The rewiring of the internal crossover is not usually hard to do, and is neither permanent or fatal (i.e. you can put it all back together later if you want to sell the speakers). Make sure you note what you disconnected (and from where), and also make sure that the electronic crossover has as close to the original crossover frequency as possible. The additional amplifier does not need to be balanced (although this does not hurt). As for being valve or transistor, this is completely up to you. My own system uses identical transistor power amps (4 of them), and this performs very well. If I had a valve amp, I would probably use that for the top end (mid+high), but you can always experiment - switch them around until you decide which is the best connection. Cheers, Rod (This is the reply i recieved from Rod Elliot of Elliot Sound Products.) You can find his Web Site at: [email protected]
Elvin, go to SoundStage "synergizing" column archives by Greg Weaver, for 3/98 good article on bi-amping and bi-wiring, http://www.soundstage.com/synergize/ With all do respect to RE above, passive bi-amping is not a waste of time and yeilds very good results. Although there are benefits to having active electronic crossover before amps, it is not mandatory, again read soundstage article. I have Musical Fidelity amps and have used passive bi-amping to good effect, again please read article.
If you want to bi-amplify, there are many good reasons to do so VERTICALLY. Vertical bi-amping means using one stereo amp for each speaker. Every different marquis of amp has different current rise times (slew rate), different input impedances, different distortion levels, different clipping thresholds, different timbral presentations and more. If you use one type of amp (say, tube) for the mids and highs, but another for the lows (say, the DNA), your music will not mesh. If you use two identical DNA's, one for each side, you will not have differing presentations of, say, a single cello (which could be played through woofers or mids/his), or harps, or piano, etc. - you will achieve a seamless whole in your presentation with vertical bi-amping. As far a cross-over mods are concerned, contact the manufacturer. They may be willing and able to help. Avoid additional external circuitry - there is significant loss with each additional resistor, capacitor, inductor, circuit board and the like. In your case, if you split the signal at the speaker inputs, you would run two speaker cables to each speaker (woofer and mid/hi). Back at the amps, you would either fit a Y-connector to your amp inputs, or (better yet)take off the top cover and solder two short sections of wire across the inputs: hot to hot and ground to ground. Use good wire from an old, unused interconnect. Each piece need only be about 2 inches long. I run an audiophile surround with FIVE McCormack DNA amps operating in just this configuration. All five speakers are rigged for vertical bi-amp. I pulled the crossovers and positioned them outboard for easier upgrading and service, but this is not required. Contact me with further questions at AUDIO [email protected] Bruce Kopitz
Hi. I am currently bi-amping my system and have done so for the past several years. Bi-amping the easy and cheap way is to have a stereo amplifier power one speaker. Get a high quality Y-adaptor with the one male end connecting with either the left or right output of your pre-amp (or the Res 55 - I have read it has a great direct output). You the run a pair of interconnects into the left/right inputs of the amp. One channel (doesn't really matter), powers the "high" and the other the "low". Refer to your speaker's owners manual for the proper wiring procedure. Do the same (with exact same make/model of amp) for the other channel. If you have the $$$ for another amp or happen to have two - go for it!! I noticed much more headroom and clarity - and I don't use an external crossover - my speaker model bypasses the internal crossover when you wire it for bi-amping - check your manual as well!) Good luck and feel free to e-mail me with questions. BTW - finding a high-end Y adaptor is NOT easy and I would suggest you use the same material/construction as your interconnects. It may have to be custom made.