Bi Amping With Active Xover

[jcmusic]

I have decided to try bi amping my setup just to hear what changes take place. I am pretty happy with it now but, I have always been curious about bi/tri amping so I am gonna give a go and see where it lands. For those interested I will setting up a active xover with two different amps, a SS amp on the woofers and my 45 tube amp on the mid/high frequency's.

[Alrainbow]

What are you using for the active crossover ? I have been down this road a few times.

[JCOConnell]

so your saying youre bicurious....lol

[jcmusic]

What are you using for the active crossover ? I have been down this road a few times.

I am gonna be using a Xilica 4080 as my xover...

[fcrowder]

Many years ago I owned a pair of the original Apogee full range speakers which required bi-amping. Given that my electronics were all Levinson (ML6A's, matched ML3's, I tried a Levinson active crossover, but in the end went back to a very simple passive crossover with a single Teflon capacitor. What was interesting at the time was the differences. The active x-over had tighter, better controlled bass and better dynamics but the passive unit had much more natural mids and highs with no trace of hardness at the top end. I suspect that x-overs have come a long way in the last 30 years.

[Dr.Ears]

I am still a believer that the fewer components in your signal path, the better off you are. Using matched ML3's is the best, you could have done. I have 4-ways using only first order cross-overs and limit my drivers to only one per frequency range, which eliminates many issues trying to achieve phase coherency.

[jcmusic]

Many years ago I owned a pair of the original Apogee full range speakers which required bi-amping. Given that my electronics were all Levinson (ML6A's, matched ML3's, I tried a Levinson active crossover, but in the end went back to a very simple passive crossover with a single Teflon capacitor. What was interesting at the time was the differences. The active x-over had tighter, better controlled bass and better dynamics but the passive unit had much more natural mids and highs with no trace of hardness at the top end. I suspect that x-overs have come a long way in the last 30 years.

Yes they have as I understand it, also I will be using a sweet 45 type tube amp on the mid/highs and I haven't heard anything yet that sounds as good as this tube. In the end though it may just be how good the xover is and the way it effects sound quality...

[Rob]

apparently the Xilica 4080 converts everything to digital and back again, or am I missing something? It also uses balanced XLR throughputs.

I tried the Pass B4 xover last year, according to Nelson its the most transparent elec xover he knows how to build. its direct coupled (no caps in the signal) and uses discrete JFETs for buffering (these devices are OOP, once they're gone he cant make more B4s) the B4 can be cascaded if you want to tri-amp, quad-amp, etc.

[jcmusic]

apparently the Xilica 4080 converts everything to digital and back again, or am I missing something? It also uses balanced XLR throughputs.

I tried the Pass B4 xover last year, according to Nelson its the most transparent elec xover he knows how to build. its direct coupled (no caps in the signal) and uses discrete JFETs for buffering (these devices are OOP, once they're gone he cant make more B4s) the B4 can be cascaded if you want to tri-amp, quad-amp, etc.

Hey Rob,
So what's your point?

[mkuller]

One of the last reviews I wrote for TAS was for a pair of Brian Cheney's VMPS FF3 SRE ribbon loudspeakers (http://www.ztexas.net/for-sale/vmps/review.pdf) that needed to be bi-amped with an outboard electronic crossover. Crossovers are not all the same and can make a big difference. The crossover Cheney brought had been designed by his pal John Curl and had over 1,000,000uF of energy storage in the power supply. Cheney said he kept adding storage as long as the sound improved and then ran out of room.

His speakers were also very sensitive to the amplifiers I used. Once I got a pair that worked (Joule Electra and Sunfire), they were seamless and sounded terrific but it was quite a process.

[Alrainbow]

You enjoy your endever doing things yourself always has some level of being proud st the end. My speakers are very old and we're in need of a new cross over
I bought a Deqx HPD 4 complex at first but it got simple over time
keep in mind it did full blown crossover and room correction and anilizing too.
Paul is still friends with the infinity founder arnie N. he had him and his staff make a new outboard cross over
i got lucky to have him design and voice it. It has internal and external adjustments. One other I considered was from pass as well it's a two part unit one crossover and one psu. Many internal dip sws.
I think you can achieve better externally as you are planning but tiime must be given to finding its place in sound. In my lampi 45 are the sweet spot too. A 300 is hewvey and can be bloated in the bass where a 45 is detail rich and remains more neutral across the whole sound.

[Rob]

Hey Rob,
So what's your point?

the Xilica relies on heavy DSP the signal goes through AD to DA converters, that would be a non-starter for me.

[Alrainbow]

I felt this way when I bought my first digital Cross over
truth is they sound different but not bad.
My Deqx adds details I did it have but does change the overall sound and its USB input so I do not need a dac but it's input is only pcm 24/192. now having said this I do like my new cross over better and my own dacs to use. It Is something feel I could easily learn to live with the Deqx.
Now here is some food for thought anyone who does EQ OR room correction is doing this method ad to da conversion. The Deqx skips one step as it inputs digital or analog and if I choose digital it's reallly a dac , cross over and room correction with timing error correction then it goes to analog.
Lastly goldmund systems have speakers that use there own dac and amp inside each speaker. Room correction too. They sound very good and it's a one stop shop and if I could afford one they are it. Just saying lol

[jcmusic]

Well true bi amping is using an active xover and different amps for each set of drivers. This way you get complete control over all the drivers, time delay, eq, phase, etc.
Anyway I just always wanted to hear the difference using an active setup so I am gonna try it.For those of you that wouldn't try because of the digital aspect, how does your room sound without being able to correct the faults???

[Alrainbow]

Lol read my post on my cross over settings and please look at the picture that shows the outcome to fix it with out dsp. Your right to try it and it has many virtues too. For me I use the deqx4 for a rs1b setup that I triamp. They sound fine and more detailed. What they and my IRS v lacked when I used it on them was weight. It did two things I did not like
one was it removed weight the second was air around the music. I was able to easily remove the device to do quick AB Comparisons. Goldmund usies this method with an amp and dac for each speaker. I can say as I heard them they are amazing in everything. Grest sound is what you like and for anyone to tell you how it should sound is for me not fair. Give advice yes but we each have our views on tone and the rest that goes with it.
Min my case if I had dsp to adjust the phase of each woofer tower it could be setup normal. I might try dsp for just the woofer columns but I think this will delay them and add to uneven time alignment. I think moving them fowward might help that is it all worth it.

[jcmusic]

Lol read my post on my cross over settings and please look at the picture that shows the outcome to fix it with out dsp. Your right to try it and it has many virtues too. For me I use the deqx4 for a rs1b setup that I triamp. They sound fine and more detailed. What they and my IRS v lacked when I used it on them was weight. It did two things I did not like
one was it added weight the second was air around the music. I was able to easily remove the device to do quick AB Comparisons. Goldmund usies this method with an amp and dac for each speaker. I can say as I heard them they are amazing in everything. Grest sound is what you like and for anyone to tell you how it should sound is for me not fair. Give advice yes but we each have our views on tone and the rest that goes with it.
Min my case if I had dsp to adjust the phase of each woofer tower it could be setup normal. I might try dsp for just the woofer columns but I think this will delay them and add to uneven time alignment. I think moving them fowward might help that is it all worth it.

That's the idea using the active xover you can adjust all the delays to be correct. Also my speakers are horns with horn loaded bass so there has to be correction to the mid/tweeter sections to match the slower woofers. Using the passive xovers with all drivers connected to them introduces feedback from the woofers and that will muddy up the upper frequecy's, hence removing the woofers and putting them on their own SS amp. This make my 2 wpc amp much better!!! Ok I took a look at the manual of the B4 no delay settings, that is a show stopper for me...