I give UP Aerial 10Ts and Power Amps


Ok, about 30 days ago, I ran a post stating my Citation 7.1, a 4 channel 210 x 4 (biamping my speakers) started cutting in and out at VERY loud levels, probably +100db, give or take. Everyone pointed to larger amps, that the speaker, a 4 ohms load, could take anything I threw at it.
Well, I took that word, while keeping my Citations, and threw a set of Jeff Rowland monoblock 7III's at them!
The babies, definitely high current, 350 into 8 ohms, 700 into 4 ohms, and a whopping 1100 into 2 (not that we are going to 2, but I suppose it could drop) ohms. That said, it happened again! WHAT GIVES?

It did this with the Casablanca, the Citation 5.0, and tomorrow I will be with the keeper, the Proceed PAV/PDSD combo. NOW, what is causing this? Could it be the speaker has a cut off to prevent any clipping, could it be the power in the house hits a wall and can't go anymore, could it be cables, power cords, what?

Or, dare I say, could I have just hit the limits of volume for a home and this set of speakers?

For what it is worth, I do not listen to things this loud, ever, or RARELY, but when changing pieces, I do PUSH to know the limits.

HELP!!!!!

Frustrated home theater guy trying to learn more about 2 channel!

Dan
Ag insider logo xs@2xporschecab
How big is your room? And yes the impedence of your speaker does drop below 4 ohms and rise above 4 ohms. The 4 ohm rating is only nominal but that shouldn't be a problem for a high current amp. You must be playing the speakers louder than you think. If so the speakers may have a protection circuit that is shutting down.
You keep playing it loud to determine the limits and then you hit a limitation and you don't know what to do.

It's possible that at that high current your amps may be running out of power if they are on 15 amp circuits.

Also, the amps may be running out of juice if any other component is drawing power from/sharing the same circuit as your amps.

Also, the amps may be running out of juice if the amps are sharing the same circuit.

Each amplifier should be on it's own dedicated 20 amp circuit and circuit breaker.

I've been informed that if you have a high powered amp, that a 15 amp circuit at the service panel can actually limit the current to the amp acting as a govenor. Even if that's not true, you should still have 10 gauge wiring, 20 amp wall outlets, and a 20 amp circuit breaker at the service panel for each amplifier. At your volume levels you're liable to trip the circuits or start a fire.

Nevertheless, since you insist on playing your system at full volume (even tho you won't admit it), you should dump whatever amps you have at the moment and pick up the used McCormack DNA-2 Deluxe Rev A that's for sale right now on audiogon.

Most amps start straining or getting congested at higher volumes, but, as Internation Audio Review pointed out, this one stays clean, clear, and unflustered.

-IMO
If the amps were being starved for power, they would start clipping and you'd blow the tweeters.

If the amps were pulling way too much from the wall and you had current limiting taking place, you'd pop the AC breakers or amplifier fuses.

Taking the above into consideration, if the speakers have built in protection, you are probably coming up against it. Logic would say that you either need a smaller room or a more efficient / higher power handling speaker.

I ran into a similar situation with a set of speakers quite a while back. Believe it or not, changing the internal speaker wiring made a HUGE difference in the output levels i was able to achieve. No more amp clipping and much better sound quality. Then again, i doubt that those speakers are "choked" like that.

Other than that, 100 dB's at your seated listening position is NOT loud. You are barely getting into "rock & roll" levels at that point. Hopefully, you were just guessing and not basing your figure on any type of actual measurements. Sean
>
Ahh, dudester, what ARE we going to do with you!!!!
I'd like to be a fly on the wall during one of these sessions when the amps clip. Are/were you the guy who directed the planes off the carrier catapult?

I have 33H driving 10t, one of the "big power" specials I had used in the past was a set of Classe' M-1000 monoblocks. M-1000= 1000w/@8ohm, 33H=150w/@8ohm. The 33H drive the 10t's considerably better than the M-1000's did.
I have never had a problem with either the amp or speaker reaching it's limits. I'm not saying the Rowland isn't good, but it may not be the match you may think it is.
Keep trying, I did, and I'm a happy (but broke) guy today.
If you want high volume don't get an 86db inefficient speaker. They can make aircraft carriers go pretty fast, but they need a nuclear reactor to do it. I am not sure of your problem, but efficient speakers of at least 93db/1watt and high power handling, will solve your volume problem. Then you won't need to push so hard. And don't get speakers with a cut out switch. Also, you need to take a little time to learn about this hobby. System matching is one of the most frequently talked about subject on this forum. Learn what speaker efficiency is, and other technical subjects and you will have less headaches. We have all had to do this so don't feel bad. The ones that have studied are the ones that are answering the questions for the people that haven't. This is okay,but as you see, you can spend alot of money and not be happy if you aren't careful.
This is the second or third time you've run this post about your 10t's for which you've received all sorts of advice. You now state that you do not really listen to music that loud and only want to know the limits of your system. So now it would seem, for whatever reasons, that you have met your limit and if you don't plan to listen that loud anyway what is the problem? It was also suggested by myself and others that you contact Michael Kelly at Aerial, but it seems you have not done so. He will be able to help you more than any of us. As you've no doubt noticed from all the posts you've received, none of the rest of us 10t owners seem to be having any problems. Suggest you call Mr. Kelly first thing Monday morning.
Sean, the amps do not have to be 'starving' to experience some to many of the affects of being starved. Simply being a little hungry is enough seriuosly hamper an amps ability to perform. And I have no idea what affects a little hunger may have at full volume, but I'm sure it's not pretty.

For example, I have a 600 wpc @ 4ohm amp on a dedicated 20 amp circuit. However, until I installed my 3rd dedicated circuit/line, my preamp shared the amp's line. The preamp only consumes something like 36 watts or so, hardly anything. When I moved the pre off the amplifier's circuit, the amp just started singing dynamics. Huge difference in the dynamic headroom.

And I 90% of the time I play my music at just over 10 percent of full volume.
Just for the record, I was the person to who sold Dan (PorscheCab) the Rowland 7s. As he drove up to my home in his van I knew he was coming as I heard his car stereo from about 4 blocks away!! (:-)

While I have very efficent speakers (Michael Green Chameleon 3s), I agree with Stehno and had each Rowland on its own 30amp Dedicated circuit. In fact I have 5 circuits, 1 for wach amp, 1 for a preamp, 1 for analog, 1 for digital.

Dan, perhaps, you need to get an electrician in to work on your AC supply....give me an email and I put you in contact with the person who did mine.
Thanks to all that have responded (again) to this post.
In deed, contrary to your thoughts, I have talked with Mike Kelley, and indeed, he felt more power from a 2 channel amp would be better served than a lesser 4 channel, biamping.
Thus, he thought the Classe would be a good match, and my thought was, the Rowland would not be any worse, if not better.

In deed, I do not listen to music this loud very often, but I do like to on occasion, as I imagine everyone here does.

Also, I appreciate the 'learn about audio' comment, nice.
I think that is what I am doing, and if there was a clean answer to this question, not only would I probably have know the solution, all the responses would be identical.

That said, I am starting to feel, the circuit is the issue.
I am running BOTH amps, as well as ALL of my gear off the same 15A circuit!

Hey, great suggestions, maybe it is the circuit!!!

Thanks, and I will search that avenue. Let me ask this, would a power regenerator, like the Monster AVS-2000 help?

D
Dan,

I used to have on one Dedicated 20 amp outlet with the rest 15. Because a reconfiguration of my system I went ahead and installed 5 dedicated 20 amp circuits for my system. I just finished setting up my system this morning using the 10T and CC3B. I went from the PM1000 to the PM2000 20amp unit. Even prior with the PM1000 I did not have a problem cranking up the volume. I have changed a number of items in my system in the past 3 weeks but I am sure the PM2000 was the biggest bang which created tighter and very controlled bass with more air to the midrange and still no sign of strain or cut outs.

Maybe it is your in coming current?

JR
Forget the power regenerator stuff, the amps draw way too much. You just solved your problem when you mention that all your stuff's plugged into one circuit, can you say bad, very bad?! I'd be on the phone to your favorite electrician, and quick.

beemer (I love my 10t's)
Aother 10T owner with dedicated 20 amp 10 guage wire circuits and NO problems. Put in dedicated circuits and then come back and tell us if you still have a problem.
I bet ya won't. Having all this stuff on one dedicated circuit is starving your 10Ts on those dynamic peaks.
Its not the equipment, its your power draw and loudness level. It would happen to anyone else with similar gear on only one 15 amp circuit if they played loud enough, too!

The Monster unit does not regenerate AC contrary to its name. Forget regenerated AC, like PS Audio Power Plants, for
high power amplifiers - too expensive. Run your power amps direct from the dedicated hopefully 20 amp wall outlet with a good power cord - I use Granite Audio 560 power cords for this purpose, and I do use PS Audio Power Plants on front end non-amplifier components.
Beemer!
This is it? With all the gear plugged into one outlet?
Plasma, a pair of SW-12 subs, a trio of Roland 7's, a citation 7.1, LD, DVD, preamp, processor, projector, screen, and of course a couple of line conditioners?

This is it? How simple. I understand this is going to make a huge difference.

Do any of you know threads that discuss what types of lines, size of cables, etc that should be run? I understand a dedicated ground should happen, what else should I do?

D
Sbruzonsky is correct. Monster is usually good to stay away from anyway. But with the current draw from your amp, you would need a very high powered AC regenerator which are very expensive.

I'm using a Foundation Research LC-2 in-line power conditioner but even that is only rated for 200 or 250 wpc so I'm suffering just a bit in that it weakens the bass ever so slightly. But it works wonders otherwise and I don't need an aftermarket power cord since it is 'in-line'. On top of that it does more that most power cords can do and costs about the same as a very nice power cord.
If you having problems with your ac lines due to excessive loads, adding any kind of ac regenerator is only going make it worst. The ac regenerator can not give you any more power than what the circuit is capable of putting. The regenrator will actually contribute more load since it's not 100% effcient.