Help me understand...

CTC564 · #1 10-19-2011, 05:30 PM

It seems the more I read on this forum, the more my head spins regarding amps and cabs...

I'm aware that parametric EQ is available on some amps, and it's a would to boost or cut a particular frequency...but how would I know WHICH frequency to boost or cut? Is it as simple as "whatever sounds good to you" or is there some kind of science to it? And what is "Q"???

I've always heard that the "rule of thumb" is---4x10=2x12=1x15

Or something along the lines of more speaker area=more volume....but bass response is only as good as the cabinet design

And what exactly is "headroom"

Would it be a good idea to run a Shuttlemax 12.0 into 2 (4 ohm) 2x12 cabs in order to get max performance and headroom from the amp? Is that OVERKILL???

Thanks in advance TB'ers....

bongomania · #2 10-19-2011, 05:38 PM

Quote:

Originally Posted by CTC564

I'm aware that parametric EQ is available on some amps, and it's a would to boost or cut a particular frequency...but how would I know WHICH frequency to boost or cut? Is it as simple as "whatever sounds good to you" or is there some kind of science to it? And what is "Q"?

Different EQ Types Explained
The practical way to think about Q is "how wide of a frequency range am I trying to affect here".

Quote:

Originally Posted by CTC564

I've always heard that the "rule of thumb" is---4x10=2x12=1x15

No, I'd forget that, pronto.

Quote:

Originally Posted by CTC564

Or something along the lines of more speaker area=more volume....but bass response is only as good as the cabinet design

THAT is true, generally.

Quote:

Originally Posted by CTC564

And what exactly is "headroom"

Headroom

CTC564 · #3 10-19-2011, 05:50 PM

Awesome info Bongomania!!! Thanks....

CTC564 · #4 10-20-2011, 01:55 PM

What about cabinet specs?

What are the keys to a more efficient cabinet design?

CTC564 · #5 10-20-2011, 02:05 PM

For example...it seems as if these specs are MUCH better than any other 4x10 cab I've looked at---

Power handling 1400 W RMS
2800 W Peak
Impedance 4/8 ?
Sensitivity @ 8 ? 106dB @2.83V/1M
SPL @ Maximum rated power 137 dB SPL max
Frequency response 37Hz to 14KHz
Size 33" x 23.75 "x 16"
Weight 79lb
Coverage pattern 60 degree
Tuning

will33 · #6 10-20-2011, 02:08 PM

Quote:

Originally Posted by CTC564

For example...it seems as if these specs are MUCH better than any other 4x10 cab I've looked at---

Power handling 1400 W RMS
2800 W Peak
Impedance 4/8 ?
Sensitivity @ 8 ? 106dB @2.83V/1M
SPL @ Maximum rated power 137 dB SPL max
Frequency response 37Hz to 14KHz
Size 33" x 23.75 "x 16"
Weight 79lb
Coverage pattern 60 degree
Tuning

Specs like that are more advertisement than "spec" and should always be taken with a spoonful of salt.....unless they come from a very few reputable builders.....very few.

CTC564 · #7 10-20-2011, 02:11 PM

Assuming that they are accurate, does this mean that a 600 watt head would be TOO SMALL and not properly matched for this cab?

They are the specs of a DNA 410 (David Nordschow)

GrowlerBox · #8 10-20-2011, 02:12 PM

Quote:

Originally Posted by CTC564

For example...it seems as if these specs are MUCH better than any other 4x10 cab I've looked at---

Power handling 1400 W RMS
2800 W Peak
Impedance 4/8 ?
Sensitivity @ 8 ? 106dB @2.83V/1M
SPL @ Maximum rated power 137 dB SPL max
Frequency response 37Hz to 14KHz
Size 33" x 23.75 "x 16"
Weight 79lb
Coverage pattern 60 degree
Tuning

Let me guess -- DNS? (Edit: you posted while I was typing)

A good deal of scepticism has been reported regarding these cabinets, largely due to the fact that these purported specifications seem to exceed the realms of physical possibility.

There is but a handful of commercial cabinet manufacturers who provide useful (and true) specifications -- Duke LeJeune who makes the Thunderchild, Alex Claber of Barefaced, Acme, and Roger Baer come to mind. In addition, there are fully specified designs from Greenboy (fEARful) and Bill Fitzmaurice, but you either build these or have them built for you.

GrowlerBox · #9 10-20-2011, 02:15 PM

Quote:

Originally Posted by CTC564

Assuming that they are accurate, does this mean that a 600 watt head would be TOO SMALL and not properly matched for this cab?

They are the specs of a DNA 410 (David Nordschow)

1) You can't assume they are accurate.

2) You can't underpower a cabinet. Imagine what might happen if you ever stopped playing or turned your amp off, or even paused between notes.

scottfeldstein · #10 10-20-2011, 02:18 PM

37 Hz from a 4x10 cab? I'm skeptical. Probably more like 47 Hz. If that.

will33 · #11 10-20-2011, 02:19 PM

With any speaker, you can drive it with as little as 1 watt...or 0 watts but that wouldn't make any sound now would it?

Your upper limit is where you start to hear it distort, regardless of what the specs say or what the power rating of your amp is.

CTC564 · #12 10-20-2011, 02:24 PM

Okay...so it's NOT similar to putting a Yugo 4 cylinder engine into a Mack truck?

How does one determine what good specs are? Just by ear?

Is it "fair" to assume that Bergantino, Aguilar and Genz Benz all make comparable 4x10 cabs?

How do you "properly" match a head and a cab?

will33 · #13 10-20-2011, 02:25 PM

Quote:

Originally Posted by scottfeldstein

37 Hz from a 4x10 cab? I'm skeptical. Probably more like 47 Hz. If that.

When you don't at least qualify it with +/- 3db, 10db or something or state how/where it was measured you can write down whatever number you want.

will33 · #14 10-20-2011, 02:29 PM

Quote:

Originally Posted by CTC564

Okay...so it's NOT similar to putting a Yugo 4 cylinder engine into a Mack truck?

How does one determine what good specs are? Just by ear?

Is it "fair" to assume that Bergantino, Aguilar and Genz Benz all make comparable 4x10 cabs?

How do you "properly" match a head and a cab?

There isn't much you can glean from numbers like that, more information is left out than is included.

Your best bet is to listen to it for yourself, next is rely on the experience of others AFTER they've used it for a while, the honeymoon's over and the new wore off.

GrowlerBox · #15 10-20-2011, 02:34 PM

Quote:

Originally Posted by CTC564

Okay...so it's NOT similar to putting a Yugo 4 cylinder engine into a Mack truck?

Er, no.

Quote:

How does one determine what good specs are? Just by ear?

Probably the single most useful thing would be a frequency-response curve, measured both on and off-axis, and the ability to interpret it. Failing that, you need to listen to them.

Quote:

Is it "fair" to assume that Bergantino, Aguilar and Genz Benz all make comparable 4x10 cabs?

In that they all make 410 cabinets, yes. Otherwise, define "comparable".

Quote:

How do you "properly" match a head and a cab?

By relying on your own experience of the voicings of the head and cabinet in question, or the experience of others whose opinions you trust. This would all be far easier if "proper" specifications were provided.

CTC564 · #16 10-20-2011, 02:38 PM

Thanks to all...ignorance truly IS bliss :-)

Seems the more I learn/research, the more my head spins

GrowlerBox · #17 10-20-2011, 02:41 PM

CTC564 · #18 10-20-2011, 02:45 PM

:-)

Apropos AND holiday related!!! Bravo

RickenBoogie · #19 10-20-2011, 02:46 PM

How she do that?

Joe Louvar · #20 10-20-2011, 03:24 PM

+1, good questions CTC546 - thank you.

This thread should be a “sticky” - seriously, it would save people a lot of time.