Help in configuring Altecs

[LICORNE]

That's what I use also 2X the power. I thought I would give the novice a prudent advice.

We often do that in permanent installations were
evry Joe come lately has access to expensive systems.

I've heard EV rear loaded custom built cliped
on AVE MARIA song.

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[Ronald Lee]

Originally posted by Old Guy:
I've always used 2x power as a rule of thumb. haven't pooped a driver in a while.

the key is- DON"T CLIP THE AMP.

You can destroy drivers at half power with a clipped amp.
One treatise is- Danger : Low Power at JBL's Tech Library. I'm sure there are others.

Power ratings for speakers are lower with clipped waveforms. Clipping by itself won't destroy a driver. But not derating the drivers when subjecting them to such a signal will.

<font size="2" face="Verdana, Helvetica, sans-serif">It not the clipping that destroys tweeters, it is the inaudible supersonic harmonics. This is from my JBL phamphlet 50777 N2 5/77 "Technical Note-Danger: Low Power."

[LICORNE]

Clipping is a form of distortion that occurs when an amplifier is overdriven, which happens when it attempts to increase voltage or current beyond its threshold.

Effects of clipping
In power amplifiers, the signal from an amplifier operating in clipping has two characteristics that could damage a connected loudspeaker:

Because the clipped waveform has more area underneath it than the smaller unclipped waveform, the amplifier produces more power when it is clipping. This extra power can damage any part of the loudspeaker, including the woofer or the tweeter, by causing over excursion, or by overheating the voice coil.
In the frequency domain, clipping produces strong harmonics in the high frequency range. The extra high frequency weighting of the signal could make tweeter damage more likely than if the signal was not clipped. However most loudspeakers are designed to handle signals like cymbal crashes that have even more high frequency weighting than amplifier clipping produces, so damage attributable to this characteristic is rare.

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[Old Guy]

Originally posted by RKLee:
[QBIt not the clipping that destroys tweeters, it is the inaudible supersonic harmonics. This is from my JBL phamphlet 50777 N2 5/77 "Technical Note-Danger: Low Power."[/QB]

<font size="2" face="Verdana, Helvetica, sans-serif">A lot more complicated than that.

While it's true those harmonics exist- there is a great deal more area under a square wave than under, say a sine wave.

That area means one thing-power.

The duty cycle is longer, meaning the power is on for a longer time. Less time for the driver to dissipate heat.

So a combination of there being more power in a square wave, and less time to shed heat, is fatal

Harmonics are only a small contributor to the overall picture. They do aggravate the situation.

[Old Guy]

I've always used 2x power as a rule of thumb. haven't pooped a driver in a while.

the key is- DON"T CLIP THE AMP.

You can destroy drivers at half power with a clipped amp.
One treatise is- Danger : Low Power at JBL's Tech Library. I'm sure there are others.

Power ratings for speakers are lower with clipped waveforms. Clipping by itself won't destroy a driver. But not derating the drivers when subjecting them to such a signal will.

[Old Guy]

meant o say "popped" surprised the auocensor let that slip thru.

[tomt]

srkredliner,

you would do allright with some low cost emneince

speakers, in the 210's-

they sound ok, and will not break the bank-

[hmole]

Here is a pair of 3156 for reasonable on EPAY.

http://cgi.ebay.com/2-match-altec-LF...QQcmdZViewItem

The 3154 should have slightly better low bass if you can find them.

The 3156 should be fine in those cabinets and for $179 how can you go wrong.
Harry

[hmole]

There certainly is truth to what you say,but others on this forum have tried this combination and not been entirely dissatisfied.
It is not as good sounding in the midbass from what I see posted, but a bit pun***** at the low end. It also handles a bit more power.
It is an overhung design and as such of somewhat lower fidelity.
Harry

[LICORNE]

The 3156 ARE RADIATOR TYPE SPEAKERS NOT SUITED FOR HORN TYPE CABINETS . Your better with Bass Horn speakers;like the 515 . Beyma makes one
but I don't have the model No. Anyway it would probably in the same price range.

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