More vs Less Cones - Impact on Tone, not Volume ?

[Munjibunga]

In my experience, adding an identical 112 cab to your rig will improve two things:

1. your volume
2. your tone

The whole is greater than the sum of its parts in most cases of stacking identical cabs. Why don't you just give it a try? You don't have to crank it and, seriously, you will love the improvement in your sound.

 

[Doner Designs]

Another thingie I think and hope I've grasped from these forums is baffle step: having two stacked cabs instead of one lowers the point (or area) of the response below which frequencies are omnidirectional, and above which a 6dB peak, for the same reason (frequencies whose wavelengths are now too short to get around the baffle are projected in half the space), is produced. While the general area is still that of low mids, the downward shift in the step due to stacking (and a wider total baffle) approaches that of the upper bass (depending on the dimensions and shape of the cabs involved) and thickens the sound.
Or sumthin.

Could you clarify the bottom line? I got thickens the sound. Are you also saying that there is a broader frequency range of omnidirectional sound when stacked or not stacked?

 

[Mark Reccord]

Could you clarify the bottom line? I got thickens the sound. Are you also saying that there is a broader frequency range of omnidirectional sound when stacked or not stacked?

Increasing the effective size of the baffle by adding a cabinet lowers the frequency where the propagation becomes omnidirectional, or in other words it allows directionality at lower frequencies than a single cabinet does and as soundwaves become more directional, on-axis SPL increases (beacause they are radiating into a smaller part of space) So when multiple cabs are involved the proportion of the spectrum that is omnidirectional decreases. These effects are exploited all the time in the PA world to create directional arrays, but to get good pattern control at true bass frequencies you need very large arrays (larger than the longest wavelength you want to be directional). So for 40Hz you'd need an array at least 28 feet long/wide to get any kind of directionality. We used to fly arrays of 2x18 Meyer subs in a line 16 cabinets tall (40' array). That gave us decent vertical control down to about 50Hz. It was a lot of work.

 

[Doner Designs]

Increasing the effective size of the baffle by adding a cabinet lowers the frequency where the propagation becomes omnidirectional, or in other words it allows directionality at lower frequencies than a single cabinet does and as soundwaves become more directional, on-axis SPL increases (beacause they are radiating into a smaller part of space) So when multiple cabs are involved the proportion of the spectrum that is omnidirectional decreases. These effects are exploited all the time in the PA world to create directional arrays, but to get good pattern control at true bass frequencies you need very large arrays (larger than the longest wavelength you want to be directional). So for 40Hz you'd need an array at least 28 feet long/wide to get any kind of directionality. We used to fly arrays of 2x18 Meyer subs in a line 16 cabinets tall (40' array). That gave us decent vertical control down to about 50Hz. It was a lot of work.

Due to a small stage, and to hear better, I typically have my amp firing sideways at me rather than pointed toward the congregation. I always figured that was fine since the lows tend to be less directional and there is PA support for the low-mids and above (the PA is not so good with the low end). I know these are nuances and that I'm overthinking it just because I like to understand the theories. Based on what you are saying, it sounds like with dual cabs it might be more important to fire toward the congregation or maybe at an angle?

 

[Mark Reccord]

Due to a small stage, and to hear better, I typically have my amp firing sideways at me rather than pointed toward the congregation. I always figured that was fine since the lows tend to be less directional and there is PA support for the low-mids and above (the PA is not so good with the low end). I know these are nuances and that I'm overthinking it just because I like to understand the theories. Based on what you are saying, it sounds like with dual cabs it might be more important to fire toward the congregation or maybe at an angle?

I don't think it will make much difference, TBH. Adding the second cabinet won't make your true low end any more directional as the array would be way too short for that and stacking them vertically won't change anything in the horizontal plane (with respect to the baffle step) because the baffle size doesn't change in that direction anyway.

 

[Doner Designs]

I love this technical talk. Thanks for all the replies.

I built some home audio speakers in high school and I'm starting to get the bug to play around with bass amp/cab building.

The coolest thing I did in HS was design and build a huge labyrinth cabinet that used a 5 inch speaker but sounded like an 8 or 10.