Re: Selling the Ampeg. What will I get now?

"Mike Rieves" <mriev@xxxxxxxxxxx> wrote in message
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"coreybenson" <coreybenson@xxxxxxxxx> wrote in message
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Upon a full re-read of this painful thread, I've come to the conclusion
that
Mike (and you) are both correct about the peak to average ratings. It's
absolutely possible/probable that amplifiers will have to handle a 10dB
peak
at any point in a given performance. What Mike's left out of the
conversation completely, and you haven't raised at all, is why this just
plain isn't a big deal.

That depends on what kind of music you're playing.
<snip lots of wordy nonsense>

Bullshit. It's not a big deal, unless you're using a crap PA, Mike. If you
have a reasonable head on your shoulders, or are doing an install, it just
isn't that hard to put together a PA that can handle whatever duty cycle you
need.

Frankly, the place where you can defend yourself (orchestral amplification),
having to amplify is so rare as to be something you're not going to have to
worry about. You're grasping at straws to defend your idiotic 20db and now
30dB numbers. 10dB, I'll agree it happens. The rest of your nonsense? Sure,
you can find somewhere the numbers have been printed, but it's NOT germaine
to this discussion, so stop grasping at straws, ok? Your lunacy will be much
less apparent if you stop speaking in esoteric extremes, Mike.

Ever hear a live band that just didn't sound clean, but you couldn't put
your finger on flaws at any particular frequency? There's a good chance
that
their PA didn't have enough headroom and you were hearing it clip on the
peaks, even though it wasn't bad enough to identify the problem as
clipping
distortion.

Thank you SO much for repeating EXACTLY what I already said. Self edit,
dude.

If you're using a didital recorder to record live music, then it's a
very
big deal, if you don't make allowances for it, you'll get some very ugly
digital clipping on the recording.

No one, besides you, has talked about digital recording, other than to
evaluate samples. I don't disagree with you're statement, but it doesn't
have a place in this discussion. Head over to Rec.Audio.Pro if you want to
discuss digital recording.

I'll add that if your bass amp or PA doesn't have enough power for the
type music and volume you're playing at, then it can be a very big deal.

Of course. No one disagrees with you. In fact, this is such an incredibly
obvious statement, it makes me wonder why you bothered to make it?

Which goes right along with what I've been saying.

Except, as usual, you had to take everything to the utmost extreme to make
people think you know what you're talking about. Instead, once again, you
look like a freaked out loon. It's too bad, really. You're almost useful.

On that same note, I've worked with (or owned) over a dozen regional
sound
companies that use the same rule of thumb most people use in the
industry:
Whatever the RMS rating of your speakers, double the RMS rating of your
amp.
This keeps the amp clean when it's getting whacked, and the vast
majority
of
pro-grade speakers can easily handle short transients of double their
RMS
rating.

No disagreement with that, and again, it reinforces what I've been saying.

Of course it does. However, it was stated in a USEFUL manner, as opposed to
talking about having to have 10x the power, blah blah blah. The problem is
you leave out half the facts when you make your extreme comments, Mike. Then
you try to fill them all in because everyone piles on and pokes holes in
your lunacy. Maybe you had those facts at the start of the conversation, but
frankly, it doesn't seem like it most of the time. Instead, you look like a
Google maniac, with mad skilz at Copy/Paste.

This is where Mike and I disagree, and frankly, it's one of the areas he
talks about where I find it hard to believe his supposed experience:
Using
an amp at the SAME rating as the speaker involved is often a source of
failure. Using an amp BELOW the speaker's rating is a fail point very
likely
to occur, unless you're aware and careful.

Using an amp at the same rating as the speaker is only a problem if
you're
driving the amp into clipping hard enough and often enough to exceed the
speaker's continuous power rating.

You are correct. However, in my experience, you are MUCH more likely to
overdrive an AMP than to push a speaker to it's limits on a regular basis.

<snip Mike's repetition>

Using an amp that's less than half the speaker's continuous power rating
isn't likely to damage the speaker because even at heavy clipping, it
isn't
going put out enough power to exceed the speaker's continuous power
rating.

While I understand the math you use to support this statement, and have even
seen others agree with you, my real-world experience has been somewhat
different, so I'll just agree to disagree.

Fortunately, most people have enough common sense that when clipping
becomes
audible they turn it down, those who don't are probably going to be buying
or reconing a lot os speakers.

I would maintain that many people can't hear amplifier clipping as clearly
as they can hear a speaker being driven past it's power rating.

On the flip side, using an amp that's rated at twice the speaker's
continuous power rating can be dangerous because that amp will be capable
of
peaks that reach twice it's continuous power rating. Example a 1200 watt
amp
with a 600 watt speaker, the 1200 watt amp may be capable of 2400 watts or
more short term peak power, and a 600 watt speaker will typically have a
peak rating of 1200 watts. That makes it dangerous if someone drops a mic,
because a 2400 watt transient can separate the cone from the voice coil,
rip
the spider and/or surround, bottom out and warp the coil, or even blow the
cone clean out of a 600 W continuous/1200 W peak rated speaker. You can
exceed the speaker's continuous power rating for short periods without
damaging the speaker, but you exceed a speaker's peak power rating at your
own risk. Many people run limiters for that reason, limiting doesn't
distort like clipping does, and it will protect speakers in the event of a
dropped mic.

Once again, if you talk in extremes, you're right, Mike. This can happen.
But, as YOU'VE pointed out, you're not going to be running said system
straight to the nuts. You're going to run it so it sounds good, and when the
microphone hits the floor on the system described above, it won't BE at full
peak power.

Math aside: I've seen more burned voice coils with underrated power amps
than I've seen destroyed speakers from over-powering. In fact, the only
speakers I've ever destroyed in the manner you suggest above was a pair of
single-18" cabs, which had been re-ported and loaded with JBL 2240's,
powered by a Crown Macrotech 2400. The AC power dipped, and the amp threw DC
at the drivers (something the MT2400 is known for in low AC power
situations, I found out later). Popped 'em right out of the gap. Pulled the
grills off when we got home, and they looked like they were screaming, if
you know what I mean. Other than that I've ONLY seen speakers with burned
voicecoils, but NEVER when powered with good clean power, from an amp that
can easily provide double the RMS.

I note you haven't called Jason Sound, Clair Bros, etc., to ask how THEY
spec their systems.

I've cobbled together some of the most cluster-f'd systems you can
imagine,
and had people come up and ask me for contact info so they can hire me
for
their next event. At one point, I'd become so good at this it was almost
all
I did... "We only have a pile of crap to work with? Call Corey. He seems
to
be able to get good sound out of almost ANYTHING..."

For the record, being THAT go-to-guy sucks. You're working your arse off
trying to keep things alive, etc. I'd much rather run the big rigs I do
these days (when I op, that is) and just keep everything down around the
Fun
level, instead of the painful.

Been there, done that, and I agree 100%!:-)

To steal a line from Brian: No you haven't.

But thanks for agreeing anyway.
--
Corey Benson

Radio by dogs, for dogs:
http://www.HenryAndBuster.com/

http://www.curbsideproductions.com/



.

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