AMP configuration

[dwayne.aycock]

Greetings all, I just finished bi-amping my speakers. I wanted to get your thoughts on my configuration.
I am using a Denon AVR 5800 as my head unit, but the pre amp section only.
As I have a HT and 2 channel needs, this is how I have set it up:

1. Center channel amp is a Denon POA 8200 driving 2 Mirage MC-Si centers.
2. Main amps are B&K EX 4420 and a B&K ST 1400 driving a pair of Mirage M3-Si. ( I use the 4420 for the low end and the 1400 for the high end).
3. Rear amps are Adcom GFA 555 -II and Adcom 535. I use these to drive a pair of Mirage M5-Si (with the 555 driving the low end and the 535 driving the upper end.
4. The back speakers are not bi-wired / bi Amped, but driven by a B&K EX 4420 as well. The back speakers are a pair of Mirage M-7 Si.

So as you can see, I really like the mirages. I know they are fussy about placement, and that they are power hungry. I have no problems with the placement as I have plenty of room. Just wanted your thoughts on my choices for amps.
Thanks, Dwayne

[JoeE SP9]

What you have (amp wise) should be more than sufficient. For the future you might want to consider using electronic crossovers and completely bypassing the internal passive crossovers. The coils and capacitors in passive crossovers contribute a certain amount of veiling. Another added benefit is the amps work on only the signal for each speaker. In your current configuration each amp carries and amplifies a full range signal.

[harley .guy07]

I agree with joeE on this one as well. I know Adcom and Mirage m si series series work great together and if the B&K sound as good you probably have one heck of a setup and very dynamic. How does your Denon work with them. I sold Denon in the past as well and have ran their receivers as preamps for Adcoms and other amps in the past with some pretty good results especially denon receivers in the price class as yours was when it was new. Other than a electronic crossover there is really nothing more to add except making sure that your speaker wires and interconnect cables are giving your continuity between all the speakers and amplifiers. Heck its winter time you should have no problem heating your theater room when playing a dynamic movie with all those amps running in your room.

[dwayne.aycock]

I have been using the Audio Quest crystal and a few Monster digital interconnects from my CD / DAC, turntable and blue ray player, as well as the HDMI out for the video. I am using speaker cables from Dayton Audio on everything that is Bi-Amped, and esoterics aurio cables in the rear. I would love to upgrade my interconnects, but the availability and possibility to try them out with my system before purchase has been an issue. I know different cables and interconnects wirk differently with different systems, but if you are not a dealer or likewise, it is hard to do a comprehensive comparison. I will add PICs of the system soon.
Dwayne

[harley .guy07]

Sounds good as long as you like the way they sound. We used XLO cables and Monster and the XLO was good but overpriced for what they did. the Monster cables higher end stuff is good but their cheaper end stuff is like lamp cord. I think if I change cables around at some time I am going to try Blue Jeans cables, they have several options and they will do custom lengths with terminated ends the way you want them termed and they are very reasonable priced for what I have heard their quality is. You are right it is hard without having to spend a few hundred or thousands on separate cables in order to try them out on your system and I know I am not going to do that knowing that I will have to sell of the ones that are not as good for a loss. About the only people that can get a chance to look at different brands of cables are professional reviewers that get equipment to review but even they might have a different opinion of the sound compared to what your ears or tastes prefer.

[dwayne.aycock]

JoeE SP9, please forgive my ignarance. I am at my weakest when it comes to crossovers. You wrote " For the future you might want to consider using electronic crossovers and completely bypassing the internal passive crossovers. The coils and capacitors in passive crossovers contribute a certain amount of veiling. Another added benefit is the amps work on only the signal for each speaker. In your current configuration each amp carries and amplifies a full range signal." How does the electronic crossover work? Where would I get them and how many would I need? On the surface it liiks like 4 or 5 one for the upper and lower of each mirage and Amp and possibly one for the center. How much do they cost, and how do I know if I am getting a good one?
Where do they go in the signal path? If they are powered, what power stream to I add them to. What is the tendency for them to add noise to the signal?
I guess you can see I am more questions than answers now.
Thanks All for the suggestions...... I am listening.
Respectfully, Dwayne

[JoeE SP9]

JoeE SP9, please forgive my ignarance. I am at my weakest when it comes to crossovers. You wrote " For the future you might want to consider using electronic crossovers and completely bypassing the internal passive crossovers. The coils and capacitors in passive crossovers contribute a certain amount of veiling. Another added benefit is the amps work on only the signal for each speaker. In your current configuration each amp carries and amplifies a full range signal." How does the electronic crossover work? Where would I get them and how many would I need? On the surface it liiks like 4 or 5 one for the upper and lower of each mirage and Amp and possibly one for the center. How much do they cost, and how do I know if I am getting a good one?
Where do they go in the signal path? If they are powered, what power stream to I add them to. What is the tendency for them to add noise to the signal?
I guess you can see I am more questions than answers now.
Thanks All for the suggestions...... I am listening.
Respectfully, Dwayne

The components in a passive (speaker level) crossover in a speaker can and do cause veiling of the signal. This is not to be confused with noise such as hiss or hum. It's more like adding layers of dirt to the window you hear speakers through.

The way you are currently bi-amping each amp amplifies a full range signal. The crossover in the speaker performs low pass filtering on the woofer signal and high pass filtering on the tweeter signal.

Electronic crossovers are AC powered devices. They have adjustable crossover frequencies, variable filter slopes (some) and individual level controls. They are connected to the preamp outputs and split the signal into high pass and low pass. The high pass output goes to the amp driving the tweeters and the low pass output to the amp driving the woofers. The tweeter amp doesn't have to amplify any low frequencies and vice versa. The speakers internal crossovers are completely bypassed.

It's possible to purchase capacitors and coils for passive(speaker level) crossovers that are as transparent and close toleranced as an electronic crossover. However, they are very expensive, usually more (sometimes much more) expensive than an electronic crossover.

I use two electronic crossovers. One for my front speakers and one for the rears. I freely admit I may be a little over the top with the one for my rears. My system is primarily for two channel music. The MC/surround stuff is an add on. I have no center channel speaker so that's not an issue.

I've described a two way crossover for bi-amping. There are three way and four way crossovers for tri and quad amping.

Besides it's more stuff to play with!!!:biggrin5:

da, I brought this up only because you asked. I'm kind of obsessive about my system. What I'm talking about is what you do when you have everything else the way you want.

[dwayne.aycock]

I am a DJ on occasion and I just happen to have the cross over downstairs. So if I am understanding you correctly, I will need the following:
A pair of Behringer CX 2310s
A pair of cables that convert RCA to XLR for the crossover and a pair that convert XLR back to RCA for the AMP that runs the high end, and the same set up for the low end. If I care the do this for the surround speakers, I just have to repeat the steps listed above. Am I correct on this, or an I missing something?
Thanks Dwayne

[JoeE SP9]

That's pretty much it although you need to bypass your speakers internal crossovers. I use RCA to XLR adaptors. I use DH Labs Bl-1 IC's (20') from my preamp to my crossove and amps and DH Labs Air Matrix IC's from crossover to amps. My front speaker cables are DH Labs Q-10 Signature

My rear speakers use a Paradigm X-30 crossover, DH labs White Lightning IC's and T-14 speaker cable.

I should point out my ESL's (both pair) have a switch that disables the internal crossover.

[harley .guy07]

I do from experience that the Mirage M si series speakers do not have a crossover bypass and he would have to take his speakers back plates apart to get this done. If I remember right the Mirage speakers at that time did not have conventional back plates to make it easy to get to the crossover so it might be quiet hard to do this. It would definitely be something for a diyer with some experience with speaker wiring and circuits. I do understand the benefit of crossing over before the amplification but I am not sure the OP wants do dismantle each one of his speakers to make this happen. But then again he said that he was a dj as well so he might have some diy knowledge and could do this no problem.

[JoeE SP9]

I was thinking the same thing. That's why this line started with me saying "in the future". I hardly expected the kind of response I got.

da, I never intended goading you into tearing your speakers apart.

[dwayne.aycock]

Believe me, I was NOT going to take then apart. Since the Mirages (M-Si series) are no longer made, any damage done to them would be difficult and possibly expensive to repair. Would I be gaining anything by just using the electronic cross over and running the high and low signals to the amps and speakers without bypassing their internal networks? Am I in danger of damaging the internal passive crossover by doing so? That was a good idea about the adapters. There is a place here in Atlanta called "dirt cheap music." They make custom cables and possibly have the adapters you are referring to. But in the end, if I am chasing my tail (causing my harm than good/ causing more problems than I am solving) please let me know. I am pretty pleased with the sound I already have, but like the rest of us, I am chasing audio perfection, (unattainable) or trying to get as close as I can. I have seen the external cross overs for about $80 each. How many would I need?
Still confused, but glad I have this forum to set me straight.
Dwayne

[harley .guy07]

I don't think it would hurt anything as long as you kept the crossover set at the same frequency that the internal crossover are set at which might help the amplifiers some but I probably will not be worth the cost if you can not bypass the internal crossovers since that is the real point of doing this to begin with.

[JoeE SP9]

I agree with harley .guy07.

[dwayne.aycock]

Understood, I will keep my money for now. What I have in the signal path so far is an EQ (Audio Control AC-101) on the top end where I can roll off the low frequencies and pass more of the higher frequencies to the amp I have running the highs. Not as good as the suggestions above, but it will do for now.
Thanks, Dwayne