biamping sr6500 with 120w to each driver.

killerb

i just ordered my sr6500 set and i want to biamp them. i have a vintage carver m4120 thats 120w a channel 4 channel amp. i want to use this amp, but im nervous about over powering them. if i set the tweeters to -3db and use my fader to futher attenuate them will i be o.k.? i know some people use close to 100w with no problem, but the extra power has me concerned. my head unit puts out 5 volts and my input sensitivity on the amp only goes to 4 volts so trimming the gains is not an option. any help will be great. thanks.

1996blackmax

That is alot of power to be going to the speakers....

The good thing about the gains is that you should still be able to keep them low enough to lower the power to the speakers. My current HU puts out 5v's and my amps lowest gain setting is 2.5v's. The thing is that the 2.5v's rating is RMS, so that is why it is not an issue. My last HU had 8v preouts and that was still not an issue.

killerb

i should be able to turn the gains all the way down and still drive the amp to max. i love the carver amp and just hate to waste it, but i dont want to blow the speakers. maybe ill just sell it and get something safe.

1996blackmax

No, you could use the amp. Just because the gains say 5'v on you HU does not mean that it will not work with the 4v input sensitivity of your amp. My amps input sensitivity range is from 250mv to 2.5v's. I have run an 8v hu to them with no problems whatsoever. Running a 5v HU to them now. You should still be able to tweak the settings to where they will be at a safe level for your speakers.

killerb

i dont have a problem with the head unit. with my gains set to minimum the head unit will drive the amp to max. power, so i will leave them on minimum. i got my o scope out and measured the max. undistorted output of my excelon head unit and found that at the volume setting of 34 i have 4 volts. with the fader set at 5 toward my rear preamp output i have 2 volts. if i run the at 2volts from my preout with the gains set at minimum i should only get half the power or 60 watts to the tweeters, and the full 120 watts to the mids. so this should be safe i asume. what do you think?

1996blackmax

Connect your gear and leave your amplifier's input sensitivity at the lowest setting (4v's). Listen to how it sounds. You may find that the volume will be at a lower level than you expected. I biamped my front speakers before. My amp can do 90 watts RMS x 4. My components are rated at 100 watts RMS. Keep in mind that my amps input sensitivity was goes from 250mv to 2..5v's, and that my HU at the time was a HU with 8v preouts, and I had no issues at all. I would assume the same to be true in your situation.

killerb

i checked the amp outputs at minimum gain with my o scope and found that the amp starts to clip at 33 on the head units volume. thats at 3.8 volts. at that volume i get 1.8 volts on my front preamps with the fader set at 5 toward the rear. this should put me at a safe power output for my tweeters with zero clipping. your right it might not be as loud as i think. now i can play with the fader to balance if needed. im really not looking for a lot of spl anyway. now i should have 120w to the mids and about 60w to the tweeters. what do you think?

1996blackmax

120 watts to the mids is alot of power. Just watch the volume and make sure that you have crossover settings at a point where they will not get pushed too hard.

killerb

yeah that is alot of power. ill wont pull the throttle that hard on these. im going to use my high pass xover on my head unit to limit the bass notes. ill probably cross them at 100hz. now i have to get a nice sub to match. thanks.

1996blackmax

No problem. Let us know how it works out.

MacLeod

Yeah, that is an awful lot of power. Im using a 50x4 amp to bi-amp mine and thats more then enough to fry em. Id recommend using something smaller but if youre set on the Carver, be very VERY careful, especially with the mids.

killerb

you might be right. maybe i wont biamp them until i get another amp. what sucks is i have a u.s. amps tu-4360 rated at 75 watts into 4 channels, but i gave it to my fiance. its hooked up to my home stereo and i dont know how to ask for it back!!! that amp would be perfect!!! i will just look for another amp. that carver amp is just awsome, and i hate to see it back in the garage collecting dust.

Thom

You're planning on bi- amping through the passive crossovers? You should be OK, but it will depend on your listening.

I've got a Zapco C2K4.0 running mine- no passives- and that amp is rated at 100W x 4. When I really crank it up I can see the clip lights flashing on the RSD, but after 4 or 5 months no problems so far. But I don't flat- out abuse them. Just slightly...

killerb

yes i was going to biamp them using the passives. after using the fader im at 60 watts to the tweeters and 120 watts to the mids. i just measured the voltage out of the amp with it maxed and then trimmed the front outputs to half that voltage with the fader. so i assume i should be getting half the power to the tweeters. for now i think i will just run them with 2 channels of my amp. this will give me 120 watts to each side. i dont really crank my music, so i was going to try the biamping. but it just seems too risky. who ever thought i would have a problem with too much power!!! also how much power do the passive crossovers eat up?

MacLeod

As long as you use common sense with the volume control you will be fine especially, as mentioned, if youre using the passive x-over. Just be careful. X-over or not, you could still overdrive your mids. The tweeters have the protection bulb in the x-over so it would probably blow before the tweets did.

1996blackmax

Get em in and use common sense, you should be fine.

killerb

thanks for all of your input. i have a few days to decide what im going to do. im leaning toward not biamping. that carver amp puts out alot of power and i think it should sound pretty good with 120 watts going to each side. its just a shame i have to waste the other 2 channels. well it could be worse. ill let you guys how it sounds. again thanks.