need input for new amp (s)

[hays0023]

Hi everyone! I am in need of some input for a new amp or pair of amps. I am currently running the classic 7100 with the 5250. I am going to be stepping up to a 7.1 system and need help with what amp to go with.

1) Purchase the 2250 and have my fronts run off of this one

2) Purchase two of the 2125 and bridge to mono to run my fronts of off.

3) Purchase one of the 2125, bridge to mono to use for my center channel and then go to a 6.1 system.

I am using Paradigm S4's for my fronts, C5 for center and S2's for all surrounds.

[J.H.]

2250 all the way. That things got major power.

[Chris D]

I'll second that...

[Peter Nielsen]

:agree: Go with the 2250! Avoid bridging if possible. Bridging is baaad....

Peter

[Chris D]

Peter, why do you say that? I'm buying a couple of Zamp v.3's, and was planning on bridging both of them to mono for more power in a Zcustom stack.

[eduardw]

Instead of bringing try to bi-amp.

http://stereos.about.com/cs/theamplifierfaq/f/bridge_mono.htm

After doing those things, you STILL have to be careful. By bridging an amplifier you essentially halve the impedance it "sees" from a speaker. So an 8 ohm speaker behaves like a 4 ohm speaker to the bridged amp. Be sure your amplifier is capable of delivering consistent power into the lower impedance without overheating or distorting before going through with the bridging process.



Eduard

[Peter Nielsen]

Peter, why do you say that? I'm buying a couple of Zamp v.3's, and was planning on bridging both of them to mono for more power in a Zcustom stack.

-You cannot use a speaker with smaller imedance than 8 ohms
-Your 8 ohm speaker will be seen as 4 ohm loads when the amp is bridged. The amp will output more power, but the "4 ohm rule of thumb" also applies - ideally the amp should have the capability to double its power in 4 ohms. If not, the amp is not ideal for driving a 4 ohm load.

That article sums it up pretty well:
"Many times, its better to simply buy a more powerful amplifier, rather than operate two different ones in bridge mode. Bridged amps usually run hotter, and excessive heat is the enemy of every stereo component."

Not necessarily a problem with the Z-series, since they're not running particularily hot anyway. Still, your speakers have to be 8 ohms or more.

Peter

[kfr01]

... and along with all that, those amplifiers that do not double power into four are generally not as well behaved, distortion-wise, when bridged.

As a side note, for more on the technical side of bridging amplifiers, see:

http://www.bcae1.com/bridging.htm

www.bcae1.com is originally a car audio site, but I've found it very educational for learning more about the technical aspects of home audio electronics as well.