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post #1 of 20 Old 01-16-2013, 02:01 PM - Thread Starter
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I have a pair of magnapan's Mg||'s. I'm pushing them with a Nakamichi 100w amp, I was listening to some music today, and the volume level was at 1.0 db. I noticed that the little red lights were coming on. Does this mean it was clipping and is harmful to the speakers or amp?
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post #2 of 20 Old 01-16-2013, 04:22 PM
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It is easy to overdrive those speakers.

The amplifier is probably not clipping, but the speakers may be reaching their physical limit of deflection, which can damage them.

This should be covered in the manual that came with the speakers.
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post #3 of 20 Old 01-16-2013, 07:39 PM
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Maggies aren't very sensitive, so you could easily clip a 100w amp. You should probably stay with the old adage of powering them with twice their rated power, and be sure the amp is comfortable at 4 ohms.

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post #4 of 20 Old 01-17-2013, 04:06 AM - Thread Starter
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Thinking of upgrading to the Emotiva 150 wpc at 8ohms 240 at 4 ohms
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post #5 of 20 Old 01-17-2013, 06:38 AM
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Originally Posted by Pat315 View Post

Thinking of upgrading to the Emotiva 150 wpc at 8ohms 240 at 4 ohms
You didn't state what impedance the Nak would deliver 100w into. If that's 8 the Emo isn't an upgrade. If 4 it is, but only by a smidge over 3dB, which isn't much. Generally speaking if you're clipping an amp you want to upgrade it by no less than 6dB, which is quadrupling the power rating.

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post #6 of 20 Old 01-17-2013, 06:41 AM
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Quote:
Originally Posted by Pat315 View Post

I have a pair of magnapan's Mg||'s. I'm pushing them with a Nakamichi 100w amp, I was listening to some music today, and the volume level was at 1.0 db. I noticed that the little red lights were coming on. Does this mean it was clipping and is harmful to the speakers or amp?


Sounds like you were clipping out that power amp.

My concern is not with the clipping but the actual power levels. IME Magnepans are not the speaker of choice if you want dynamic sound.


While your Magnepans may be OK with a 100 wpc power amp that is not being clipped, clipping the power amp is an effective but undesirable strategy that sacrifices sound quality for more power. If you clip a 100 wpc amp severely enough, the average power from it can be on the order of doubled.
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post #7 of 20 Old 01-17-2013, 06:47 AM
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Originally Posted by Bill Fitzmaurice View Post

Quote:
Originally Posted by Pat315 View Post

Thinking of upgrading to the Emotiva 150 wpc at 8ohms 240 at 4 ohms
You didn't state what impedance the Nak would deliver 100w into. If that's 8 the Emo isn't an upgrade. If 4 it is, but only by a smidge over 3dB, which isn't much. Generally speaking if you're clipping an amp you want to upgrade it by no less than 6dB, which is quadrupling the power rating.

Good points.

One problem is that there are a number of different speakers that are called the MGII

http://digilander.libero.it/pasqua49/COLLEZIONE%20HI-FI/MAGNEPLANAR%20MGII/Magneplanar%20MGII.htm

Model
Year
Speaker inputs
Impedance
Dimensions (“)

MGII 1973
No fuse- Mono ampli
6 Ω
22 x 71 x 2

MGII improved 1975(?)
Fuse – Mono ampli
6 Ω
22 x 71 x 2

MGII A 1978
Fuse – Mono ampli
6 Ω
22 x 71 x 2

MGII B 1981
Fuse – Bi ampli
6 Ω
22 x 71 x 2

MGII C * 1987
Fuse – Bi ampli
5 Ω
22 x 71 x 2

AFAIK in every case the speaker is fused for 3 amps with a regular medium delay fuse. IME this fuse can be blown with a 100 wpc amp, perhaps at the cost of some clipping.

Experienced Magnepan owner lore is that blowing this fuse often may be followed by permanent damage to the panels and an expensive rebuild job.
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post #8 of 20 Old 01-17-2013, 07:01 AM - Thread Starter
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I bought the Maggie's and Nakamichi in the mid to late 80's. I know the Nak is a 100 wpc, not sure at what ohms I'm assuming its at 8 ohm.
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post #9 of 20 Old 01-17-2013, 07:13 AM
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Getting a larger amplifier will make it easier and quicker to damage your speakers.

Maybe you should just realize that those speakers are limited in how much volume they can put out without damaging them.

Turn down the volume or get some speakers capable of the sound levels you seem to be pushing for.
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post #10 of 20 Old 01-17-2013, 09:25 AM
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Do you have a sub? If not adding one would take the low frequency load off both the maggies and the nak and probably both cure the problem and sound better.

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post #11 of 20 Old 01-17-2013, 09:31 AM - Thread Starter
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Quote:
Originally Posted by Bill Fitzmaurice View Post

Do you have a sub? If not adding one would take the low frequency load off both the maggies and the nak and probably both cure the problem and sound better.
Yes I have a sub I set all speakers to small
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post #12 of 20 Old 01-17-2013, 11:46 AM
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Yes I have a sub I set all speakers to small
Do the maggies sound strained? Clip lamps flashing on occasion doesn't necessarily indicate a problem. Running constantly would.

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post #13 of 20 Old 01-17-2013, 01:12 PM - Thread Starter
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No they sounded ok the light only came on occasionally.
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post #14 of 20 Old 01-17-2013, 01:14 PM - Thread Starter
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I can't remember those ever coming on before not if the amp is under powered or just old.
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post #15 of 20 Old 01-17-2013, 03:01 PM
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Originally Posted by Pat315 View Post

I can't remember those ever coming on before not if the amp is under powered or just old.
Amps aren't like people, when they get old they don't lose the ability to work as hard as they used to. Unless you see the lights coming on often I wouldn't be concerned.

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post #16 of 20 Old 01-18-2013, 05:40 AM
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Originally Posted by commsysman View Post

Getting a larger amplifier will make it easier and quicker to damage your speakers.

Maybe you should just realize that those speakers are limited in how much volume they can put out without damaging them.

Turn down the volume or get some speakers capable of the sound levels you seem to be pushing for.

Can you explain how "getting a larger amp will make it easier and quicker to damage your speakers"? I'm thinking just the opposite.

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post #17 of 20 Old 01-18-2013, 05:49 AM
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Can you explain how "getting a larger amp will make it easier and quicker to damage your speakers"? I'm thinking just the opposite.
Neither is the case. Speakers are damaged by over-powering. That can happen with a small amp pushed too hard, it can come with a large amp at moderate gains. In either case the speaker will audibly distort at levels well below where damage will occur. In the case of a small amp pushed to clipping most of the distortion will be sourced in the amp, with a large amp most of the distortion will be sourced in the drivers, but in both instances the warning sound of distortion will be heard. Ultimately it's the ignoring of that warning that causes blown drivers.

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post #18 of 20 Old 01-18-2013, 06:00 AM
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Originally Posted by Pat315 View Post

I can't remember those ever coming on before not if the amp is under powered or just old.

if you didn't get clipping before but get clipping now, the most likely explanation is that you are pushing the amplifier a little harder. There are many possible explanations for this.

One possible cause that you probably don't want to hear about is either long term or short term loss of sensitivity of your ears. This loss may be short term due to something like a head cold, or it can be long term and the consequence of of things like aging.

It might be as simple as playing different recordings that make different demands on your system. For example, recordings that distribute more of their energy to the frequency extremes take more power for equal loudness than recordings that focus more of their energy in the middle range.
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post #19 of 20 Old 01-18-2013, 06:05 AM
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Quote:
Originally Posted by commsysman View Post

Getting a larger amplifier will make it easier and quicker to damage your speakers.

Maybe you should just realize that those speakers are limited in how much volume they can put out without damaging them.

Turn down the volume or get some speakers capable of the sound levels you seem to be pushing for.

Can you explain how "getting a larger amp will make it easier and quicker to damage your speakers"? I'm thinking just the opposite.

The idea that a less powerful amp is more likely to damage your speakers is an audiophile myth that has been used to trick people into buying more powerful amplifiers than they need.

Speakers are a little like light bulbs in that they are more likely to burn out if they receive higher voltages. One of the things that more powerful amplifiers do is make it possible for your speakers to receive higher voltages.

Let's say that your current speaker and amp situation is like running 120 volt light bulbs on 120 volt power. If you get a power amp with 4 times the power rating and turn the music up to its limits, it will be like running 120 volt light bulbs on 240 volts. If you've ever actually done such a thing the experience is relatively short experience because the bulbs don't last very long.
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post #20 of 20 Old 01-18-2013, 07:15 AM
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Originally Posted by arnyk View Post

The idea that a less powerful amp is more likely to damage your speakers is an audiophile myth that has been used to trick people into buying more powerful amplifiers than they need.
Like most myths this one has its basis in fact. A clipped waveform has far higher power density in the harmonics than a clean waveform. The typical 5% of total power content that lies above 5kHz can be 20% or more with a heavily clipped signal. That results in severe overpowering of a tweeter, and the death of same. Midrange drivers can also be vulnerable. Woofers and subs are not. Where the truth ends and the myth begins is when a source says that 'clipping kills speakers', as opposed to the accurate statement that clipping can kill tweeters and midranges.

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