Acme B-112 vs Barefaced Big Baby

[BassOnTheSide]

I've run many many simulations in Bassbox pro, with an 18 vs 15 vs 112 vs 212, and in pretty much every one, the 18 came out favorable for what I'm looking for. I guess I must have some uncommon requirements or preferences.

 

[ThisBass]

I've run many many simulations in Bassbox pro, with an 18 vs 15 vs 112 vs 212, and in pretty much every one, the 18 came out favorable for what I'm looking for. I guess I must have some uncommon requirements or preferences.

LOL,
you have your preferncies, so nothing is wrong.
There are many of paramters that possible may let you prefere one distinct paramter over other different pramters of a driver design. That's nothing wrong doing it this way. Everybody is doing it this way, with all the tradeoffs

 

[CL400Peavey]

It should be intuitively obvious that a big cabinet with a big driver is going to have a higher sensitivity at the lower frequencies. Is that not obvious?

Why? What about driver size alone tells you anything about response or sensitivity? There are a number of other specs that do tell you this.

Well of course, assuming those "all else being equal" things. I think I'm failing to make my point

Edit: Also, I didn't say I was ignoring excursion. To me that's one of the "obvious" things that is covered under "all else being equal".

The problem with this is, it is very rare to find meaningful "All else being equal" examples. Even when comparing drivers of the same size, there are a number of other characteristics that can be different and have a huge impact on the sound/performance of a driver.

Agree that cab size makes more difference to low response than driver size.
At the other hand within a family of drivers those with bigger diameter "demand" larger cab volume anyway just to compare apples to apples.
For example if a cab is rather large in relation to driver specs than the benefit of lower low-response and way better efficience comes "naturally" along with the bigger diameter (which naturally demands bigger cab size).

Clearly for an equal cab size lots of smallish drivers can outperform the bigger diameter cones regarding low response cause the cab size then is (often) to small to get best results with driver specs of the larger cone diameter.

same net cab volume for both
white: 3015LF /F3=66Hz
yellow: 3010LF /F3=43Hz
View attachment 943571
For the 3010LF xellow the net volume seems a little to big while for 3015LF yellow the net volume is to small.
The crappy "average" efficience tells a lot about how the 3010LF gets pretty good low-response.

max acoustic power
View attachment 943574
the smallish cone can't compete with the large cone.
The noticeable valley around 50..100Hz also tells that for the 3010LF net volume should be smaller while tuning somewhat higher

For the record, I compared apples to oranges in this case!

More practical considerations, same net volume both cabs,
most hated combination 410+115
white 115 3015LF /F3=44Hz, Fb=45Hz
yellow 410 3010LF /F3=51Hz, Fb=48Hz

normalized response
View attachment 943599

SPL 1 watt input power
View attachment 943600

BTW group delay looks perfect for "matching"

These drivers are about the best example for "all else equal" as they use the same motors and pretty much just change out the baskets and cones. The differences illustrate what changes in cone mass will do. And the similarities show that a small driver doesnt specifically produce better high frequency response.

It's the same like horse power means nothing but horse power, actually nobody would assemble a Ferrari engine into a truck as well nobody would assemble a truck engine into a Ferrari allthough horse power is the same.

Pardon?

Dodge Ram SRT-10 - Wikipedia, the free encyclopedia

Jeep Grand Cherokee - Wikipedia, the free encyclopedia

 

[ThisBass]

All things beeing equal means system/cab Qtc shall be equal just to compare apples to apples.
For raw Qtc = 0.65 target the proper cab net volumes was as follows:
DL II 2510: 38 liters ( 1,342 cu ft)
DL II 2515: 106 liters ( 3,743 cu ft
KL 3010LF: 13 liters (0,459 cu ft)
KL 3015LF: 151 liters ( 5,333 cu ft)

Fc Fb F3 (all things being equal)
DL II 2510: Fc 82Hz / Fb 53Hz / F3 56Hz
DL II 2515: Fc 72Hz / Fb 47Hz / F3 53Hz
KL 3010LF: Fc 93Hz / Fb 60Hz / F3 75Hz
KL 3015LF: Fc 63Hz / Fb 41Hz / F3 41Hz

For all things beeing equal consideration the 3010Lf provides a rather "crappy" low end but (as big benefit) demands the smallest chamber in the field.

As Qtc is equal to all and Fb calculated by same formular so roll-off curve at the low end looks very similar to all and system damping is just the same, of course F3 points are very different but, it's nothing but comparing apples to apples.

Of course the number for Qtc can vary a lot, depending on designers goals but, keeping things equal is the requirement just to compare apples to apples.

A typical "trade-off" to get more impressive F3 with the 3010LF is to get with lower Qtc around 0.5 by enlarge the chamber volume. The "raw" weaken low response then can be offset by lower tuning Fb, which then generates a roll-off that looks like "fall off like a rock" below F3.
This "sharp" roll-off may be liked, or even not, it all depends, there is no free lunch.