mustang guy Posted September 7, 2013 Share Posted September 7, 2013 My intent is to bi-amp a speaker which has a bass impedance of 8ohms. I have not purchased a compression driver. What I am wondering is, what are the ramifications of using a 16ohm driver for the horn? My amp will be a Yamaha P5000S. The 16's are more abundant on the second hand market, and cheaper to boot. Quote Link to comment Share on other sites More sharing options...
Don Richard Posted September 7, 2013 Share Posted September 7, 2013 Not an issue if biamping. The bandpass gains on the crossover will have enough adjustment range to handle the impedance difference between the HF and the LF. Quote Link to comment Share on other sites More sharing options...
mustang guy Posted September 7, 2013 Author Share Posted September 7, 2013 Not an issue if biamping. The bandpass gains on the crossover will have enough adjustment range to handle the impedance difference between the HF and the LF. That's great news for me, thanks Don. Quote Link to comment Share on other sites More sharing options...
Deang Posted September 8, 2013 Share Posted September 8, 2013 Assuming you're doing real biamping as opposed to "fools biamping" with passives. Quote Link to comment Share on other sites More sharing options...
mustang guy Posted September 9, 2013 Author Share Posted September 9, 2013 Assuming you're doing real biamping as opposed to "fools biamping" with passives. I am using a DCX-2496; however, if I were going to use a passive "fools biamp", I would think a steep slope 3rd order crossover like this Butterworth used between the preamp and the amp would do nicely. Would this not work due to current requirements? I would think very tiny caps and inductors would only be needed since the output currents of the preamp are low voltage. Quote Link to comment Share on other sites More sharing options...
djk Posted September 10, 2013 Share Posted September 10, 2013 A passive crossover between the preamp and amplifiers is not 'fools biamping', it's the real deal. The values calculated must be based on an impedance high enough for the preamp to drive, probably 600Ω or higher. I used to build these kind of filters all the time, usually designed around 2K impedance. Just because a preamp is rated to drive 600Ω doen't mean it will sound good doing so. Quote Link to comment Share on other sites More sharing options...
mustang guy Posted September 10, 2013 Author Share Posted September 10, 2013 Oh. Fools biamping is after the amplifier. You're talking about a 1st order network with a capacitor on the HF channel and an inductor on the LF channel. I'm trying to wrap my head around what wouldn't work about that. I know it would have very gradual 6db/octave slopes, but each driver would still get a full channel of the amplifier and preamp. Perhaps I need someone to define a fools biamp setup. Does that mean full signal is sent to each channel? Quote Link to comment Share on other sites More sharing options...
Don Richard Posted September 10, 2013 Share Posted September 10, 2013 Yes, a full range signal to two amps in parallel with the passive crossover doing the crossover function. Quote Link to comment Share on other sites More sharing options...
djk Posted September 11, 2013 Share Posted September 11, 2013 "Oh. Fools biamping is after the amplifier. " Correct. It should have been called duo-amping, not bi-amping (a long established practice, well defined). "You're talking about a 1st order network with a capacitor on the HF channel and an inductor on the LF channel. I'm trying to wrap my head around what wouldn't work about that. I know it would have very gradual 6db/octave slopes, but each driver would still get a full channel of the amplifier and preamp. Perhaps I need someone to define a fools biamp setup. Does that mean full signal is sent to each channel?" Crossover parts after amplifier = fools's bi-amping, crossover parts ahead of amplifier = the real deal (bi-amping). Re: Question: amp power and bi-amping Posted by djk (M) on December 23, 2001 at 02:21:45 In Reply to: Question: amp power and bi-amping posted by Tony B. on December 22, 2001 at 13:56:50: If you use an electronic crossover and bi-amp a speaker like a Klipsch Cornwall with a 50W amp on the bass and a 10W amp on the mid and hf it will play as loud as a 400W amp through the passive crossover.If you 'bi-amp' your Newform speakers with a 250W amp on the bass and a 160W amp on the hf without an elecronic crossover it will play as loud as the 160W amp would play running both.The 4:1 benefit for bi-amping is only there when the spectrum is divided ahead of the power amps and when the division point is near the mid point of the spectral distribution of energy.On a voltage basis the division occurs around 250hz.This must be weighted by the peak to average ratio so that the equal energy point for above and below the crossover is about 500hz.This is also affected by the slope of the crossover.For the example of the Klipsch Cornwall it has a 600hz crossover point.If the drivers were the same efficency then 50W + 50W would = 200W through the passive crossover.In reality the HF is 10dB more efficent than the LF so we only need 50W + 5W to = 200W.If the HF remains undistorted it will mask distortion from the LF amp driven slightly into clipping.This means that if we use a 10W HF amp with a 50W LF amp it would take 400W to play the same level undistorted through the passive crossover.If you 'bi-amp' your Newform speakers without an electronic crossover each amp will be receiving full range signal and will clip at the same point it did with only one amp hooked up to the speakers.It does sound different to do this, but make no mistake, you will not be getting the benefits of dividing the signal ahead of the amplifiers. Quote Link to comment Share on other sites More sharing options...
erik2A3 Posted September 17, 2013 Share Posted September 17, 2013 "Fools biamping" ? Can actually sound quite good. Quote Link to comment Share on other sites More sharing options...
djk Posted September 17, 2013 Share Posted September 17, 2013 So what? Real biamping can sound even better. If you're going to all the trouble and money, why not do it right? Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.