I think I'm misunderstand something...

[computerpro3 10+ year member]

Hello,

Right now my front-stage setup is as follows:

Focal Polyglass 165V1 (although I have ordered 165KP2 Upgraded)

Zapco Reference 360.4

Alpine IVA-W200 (will buy PXA-H701 next month)

I have a very basic question, but one that I can't seem to find the answer to. I'm not quite sure how to ask it though...

The other day I decided to bridge the Zapco to give the Focals 180w RMS per side. My question is, why is this any different from the un-bridged 90w RMS at normal volumes? I can clearly hear a difference - much greater midbass, the harshness went away, and the speakers sound more natural and authoritive overall. And i'm not imagining this, I have very good ears (piano performance major) and and accustomed to very high end sound (Melos SHA-Gold Reference/Grado RS-1).

Looking at this logically, I shouldn't be hearing a difference, correct? At normal, decently loud but not blasting volumes, the Focal's shouldn't even be close to using 90w RMS, correct? The gain on the zapco is set to about halfway and the headunit volume is about 18-19 out of 33. Why would the extra wattage matter when it's not even being used, especially on an amp like a Zapco that won't even blink when putting out its rated wattage?

When people claim that they got huge gains when going from 100w RMS to 250w RMS, they are only talking about at high volumes, right?

I guess I'm trying to ask two basic questions:

1. At normal volumes, when bridging an amplifier, the speakers aren't using any more power than they would be with the amp operating in unbridged mode, correct?

2. If the above holds true, then why in a high quality amplifier such as a Zapco/Audison/etc does having headroom matter? I can see how it would help in a cheap amp that doesn't put out what it is rated for, but I can't see how it would in a quality one where going by the oscilliscope, operating at 5w or 100w from its rated peak doesn't matter in terms of clipping.

Sorry if this seems stupid, but I can't quite wrap my mind around it.

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[pickup1 5,000+ posts]

#1.the power will be doubled in the bridged mode.they will be using twice the power.

doubling your power only gives you a 3 db gain,you'll hear a diff.,but not nite and day.

#2.headroom is for dynamic peaks in the music where it requires 2 to 3 times the "rated" power of the amp.but only for milli seconds.

cheap amps have poor build quality and small caps inside.cheaper boards.

thats why you see 1000 watt amps for 29.95 at pep boys.

doesnt zapco double their power into 2 ohms?you'll get more than 180 per side,wont you?

 

[computerpro3 10+ year member]

How can it be using twice the power if the volume is the same? I don't neccessarily want my music 3db louder (as I already listen quite loud), so I turned down the head unit to adjust to my previous level. So twice the power may be on tap, but I'm not using it, correct?

 

[Prowler573 5,000+ posts]

When your amp was setup for 90w RMS per channel you didn't ever actually get 90w per out of it.

Not listening to music, anyway.

But whatever actual wattage you were feeding those components (at whatever volume setting) assuming all else is equal (gain settings, crossover adjustments, etc) you're still going to be effectively doubling the power feeding the comps when going from stereo mode to bridged mode.

 

[inapontiac 10+ year member]

Can I get that Alpine off of you when you upgrade? PM me...