Why so much Wattage ?

[Kevin C]

I am looking at moving to a McIntosh system. Most of the speakers I look at are highly efficient and need less than 100watts.

The MAC7200 and MC8900 have 200WPC

If I invest in a Klipsch Heresy or Cornwall, the max Watts is half that?

Am I missing something?

 

[TSmith8605]

Many popular speakers are not anywhere near as efficient as those you are considering. Also the relationship between perceived increases in loudness and amplifier power is logrithmtic which means adding 3 dB of loudness (an amount that is perceived as noticeably but not much louder) requires twice the power. Turn it up again, and twice the power again.

So with a Cornwall with a sensitivity of about 101 dB (@1Watt/@1 Meter),10 Watts is likely more than sufficient but a speaker like a Magneplaner with an sensitivity of 86 dB (@1Watt/@1 Meter) would require 15 dB more from an amplifier to achieve the same acoustic power (loudness) - that's 320 Watts.

Also, the amount of power needed increases dramatically as you move farther from the speaker.

I once heard a pair of restored / recapped original Cornwalls in a very large room driven by a pair of MC 30 amps (30 W) and the sound was wonderful.

You can also research the benefits of having "headroom" allowing the amplifier to support short-duration peaks in power above the average level that are common in actual music.

Crown has an online tool that I like that gives an idea of amplifier power needed to achieve a desired loudness level given distance from the speaker and the speaker's sensitivity.

You can get free sound pressure level meter aps for your smart phone and use one in you listening position to get a rough idea of how loud you like to listen and you can measure the distance to your speaker and then using the speaker sensitivity spec, you can use the Crown tool to estimate approximate power required.

For close to the examples I have above (and with 3 dB of headroom) to achieve 98 dB (really loud) at 3 meters (about 10 feet): the Cornwall needs 9 Watts and the Magenplaner needs 285 Watts.

 

[Kevin C]

Thank You - so now, do I bother with a McIntosh, or Bother with a Cornwall, or get them both, and not turn the knob to 11

 

[c_dk]

A customer at one of Gow's presentations asked him the same question, basically why his companies speakers were so inefficent compared to other brands.

He talked about lower distortion, true 20 hz bass response, wide dispersion etc. etc.you know the typical technical talk. He then smiled and said......" I also happen to own a company that makes big amps so we can".

 

[TSmith8605]

Thank You - so now, do I bother with a McIntosh, or Bother with a Cornwall, or get them both, and not turn the knob to 11

That's your call. Go listen if you can and research as best possible and then decide. McIntosh does make power amps of lower power such as the MC 275 and MC 152 which would require a separate preamp. If you go McIntosh vintage, you get a large variety of lower-power options like the MC 30, MC 225, MC 240, MC 275, MC 2505 and mono variants of these.

 

[sKiZo]

Bass and headroom ...

Check speaker specs and figure on about 80% amp load at your maximum peak SPLs. Room size will have a major impact on what you hear in the primary listening area.

Check the small print too. My "classic" McIntosh amp is rated at 200wpc, but can handle 400w instantaneous peaks gracefully without popping into protection. Also factor in any post processing like bass enhancement or expansion - I do both, and that can easily double the demand on the amps.

 

[62caddy]

I am looking at moving to a McIntosh system. Most of the speakers I look at are highly efficient and need less than 100watts.

The MAC7200 and MC8900 have 200WPC

If I invest in a Klipsch Heresy or Cornwall, the max Watts is half that?

Am I missing something?

Put it this way:

A one (1) watt amplifier with 101 dB speaker would play as loudly as a 10 watt amplifier with a 91 dB speaker or a 100 watt amplifier with an 81 dB speaker.

A 10 watt amplifier with a 101 dB speaker would play as loudly as 100 watt and 1,000 watt amplifiers with 91 dB and 81 dB sensitivity speakers respectively.

The bottom line is that very little power is needed to drive a pair of Cornwalls for high SPL; a pair of Klipschorns need even less. PWK himself used to say all the world needs is a good 5 watt amplifier.

 

[damacman]

I don't have that problem here, thank goodness.

 

[Yamaki]

For me it's the headroom my amps provide to handle the peaks without them bursting into flames.

My friend describes the combination of my MC501's (500W @ 2, 4 or 8 ohms) and the Aerial Acoustic Model 8 speakers (300W @ 8 ohms) as "effortless".

 

[Dana Hutchins]

I don't have that problem here, thank goodness.

 

[Dana Hutchins]

Klipsch heritage line and McIntosh(especially tube) are a very sweet combo.

 

[Chubba]

This is cool.

 

[CruzBay]

I don't have that problem here, thank goodness.

Just had 3 20 amp DL's installed in my room.

 

[kevzep]

Yes not something I need to worry about either.........

 

[damacman]

Yes not something I need to worry about either.........View attachment 1645900View attachment 1645914

Now that's just ridiculous! Lmfao ...

 

[SaturationPt]

I like flexibility. If you decide to buy a pair of power-hungry speakers, you're covered.

 

[sberger]

I don't have that problem here, thank goodness.

Do you own a cat by any chance?

 

[kevzep]

Now that's just ridiculous! Lmfao ...

Isn't it though, but entirely necessary at times!! Especially when I get my Parliament albums out!!

 

[damacman]

Do you own a cat by any chance?

No sir, allergic.

 

[onwardjames]

Wattage gives you headroom, is my understanding. Everything is happier when the amp bullies the speakers, not the other way around.