Give some examples of a bad design

[rdk]

What are some obvious things you would notice about a bad cab design?

I saw a 4x10 cab being played with a 1x18 cab. The 4x10 was not ported but the 18 was. When the cab was being played live, I almost feel like the higher notes on the bass disappeared in the mix. The cab had good tone, but it just didn't seem to cut through the rest of the band at all. Both cabs were hand built with crappy Madison 10" speakers. Not sure what the 18 was. Any thoughts or theories?

[B-string]

The cab is not the only component in question. Start with the bass guitar setup, strings, control settings, pickups and players style. From there, the amp and the way the player uses the "eq" settings, the cab and if it is properly phased to the miss-matched 18". Add a major fault of mixing a 410 and 118 cab, the room acoustics.

[rdk]

Originally Posted by B-string

The cab is not the only component in question. Start with the bass guitar setup, strings, control settings, pickups and players style. From there, the amp and the way the player uses the "eq" settings, the cab and if it is properly phased to the miss-matched 18". Add a major fault of mixing a 410 and 118 cab, the room acoustics.

What does it mean to be properly phased? And what are your thoughts on a 4x10 being used with a 1x18 and why?

[packhowitzer]

take a spin through the FAQ sticky on cabs. this will answer all your questions and then some!

AMPS FAQ!! Info on OHMS, Allsize RIGS-OverUnderPowerCabs DIY TechTalk-Links

[B-string]

Originally Posted by packhowitzer

take a spin through the FAQ sticky on cabs. this will answer all your questions and then some!

AMPS FAQ!! Info on OHMS, Allsize RIGS-OverUnderPowerCabs DIY TechTalk-Links

^ This will save a repeated 1/2 to 3/4 page post.

Originally Posted by rdk

What does it mean to be properly phased? And what are your thoughts on a 4x10 being used with a 1x18 and why?

Unless the the cabs are run bi-amped with the proper high pass on the 118 and low pass on the 410 it becomes an acoustic mess. (GREATLY simplified answer). Phase is both cabs pushing at the same time instead of one being electronically "out of phase" by pulling the cones in as the other cab pushes out.

[Joe Louvar]

Give some examples of a bad design

There is no perfect loudspeaker design - all loudspeakers designs are a compromise of pros and cons.

But some are better than others and what looks good on paper doesn’t always sound best in real life - but more often than not.

EDIT:
+1, to the FAQ.

[rdk]

Originally Posted by B-string

^ This will save a repeated 1/2 to 3/4 page post.

Unless the the cabs are run bi-amped with the proper high pass on the 118 and low pass on the 410 it becomes an acoustic mess. (GREATLY simplified answer). Phase is both cabs pushing at the same time instead of one being electronically "out of phase" by pulling the cones in as the other cab pushes out.

Are there any Other methods of making this setup in phase other than bi-amping?

[sad_katz]

Originally Posted by rdk

Are there any Other methods of making this setup in phase other than bi-amping?

Yes - dump either one of the cabs and buy another identical cab to the one you end up using.

AFAIK, modifying the cabs to get them in-phase is simply not worth the hassle.

[rdk]

Originally Posted by sad_katz

Yes - dump either one of the cabs and buy another identical cab to the one you end up using.

AFAIK, modifying the cabs to get them in-phase is simply not worth the hassle.

What about hybrid cabs. I see some custom companies mixing a lot of different size speakers in one enclosure. This is one I've seen recently

A 4x10 & 1x12 on top and a 15 on bottom. All one cab but separated by a shelf inside so its 2 cabs in 1 essentially. Does this seem absurd? Basically. The 4x10 was setup with the 12 in middle taking a tweeters place.

[billfitzmaurice]

Originally Posted by rdk

A 4x10 & 1x12 on top and a 15 on bottom. All one cab but separated by a shelf inside so its 2 cabs in 1 essentially. Does this seem absurd?

Totally absurd. There is no advantage to using different drivers within the same passband.

[staindbass]

where you are standing in the room has alot to do with what your hearing when it comes to bass. lots of peaks and dips. the speakers may have been fine.

[rdk]

Originally Posted by billfitzmaurice

Totally absurd. There is no advantage to using different drivers within the same passband.

I don't know how the setup worked really but is it possible to even design a crossover network for that cab to have NOT been absurd or is it pretty well pointless or bass guitar regardless?

[billfitzmaurice]

Originally Posted by rdk

I don't know how the setup worked really but is it possible to even design a crossover network for that cab to have NOT been absurd or is it pretty well pointless or bass guitar regardless?

The problem isn't the crossover, its the drivers. Electric bass tens through eighteens are all designed to operate in the same passband.

[Windreaper]

Originally Posted by rdk

I don't know how the setup worked really but is it possible to even design a crossover network for that cab to have NOT been absurd or is it pretty well pointless or bass guitar regardless?

There is no point in designing a crossover for that cab since none of the drivers in question, especially in that configuration, make for good mid driver candidates due to their diameter alone (beaming is directly related to the diameter of the radiating surface, combinations such as 4x10 can be thought as one large surface for this purpose).

[Joe Louvar]

Originally Posted by staindbass

where you are standing in the room has alot to do with what your hearing when it comes to bass. lots of peaks and dips. the speakers may have been fine.

+10
And moving even a foot or so can make a big difference too.

[will33]

That would be a bad design for the same reasons people advise against using a 410/115 stack. Power distribution and phasing. Speakers have different phase response throughout their passband, it's not just one pushing while the other's pulling. Mix two together that have different phase response and you get all kinds of peaks and dips in the response. Some frequencies disappear and others are enhanced. The result is a smeared, unclear sound. The mesa powerhouse 1000 or any other speaker that has different drivers all trying to play the same frequencies is an example of a bad cab.

For good examples of mixing drivers look at the fearful, barefaced, roger baers cabs and good PA cabs. These use dedicated woofers, mids and sometimes tweeters. You use a crossover and each component is only playing the frequencies it's best at/designed to do instead of one speaker or a bunch of regular speakers trying to play it all. Those woofers are designed to excel at producing lowend and thus don't sound that great trying to play middle or upper frequencies themselves. The mid drivers excel at playing middle frequencies and spreading them widely, but don't have any bass, etc. The "whole is greater than the sum of the parts" thing.

Examples of decent cabs that use oneway speakers would be most 210's if you stand them on their side, Genz's 212 that has vertical driver alignment, or most 215's. These use the same speakers playing the same frequencies and arrange them for the best horizontal dispersion.

Bad examples of oneway cabs would be most any 410 or 310, 212's with the drivers mounted in opposite corners, etc.