the more common term is “acoustic impedance”
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New, and confused about size vs. tone
- Thread starter ColoradoRex
- Start date
the more common term is “acoustic impedance”
If you're new to this, I think you need to start feeling fine with being confused about the relationship between the physics we were taught at school and bass tone.
Worst experience of my recent life was getting a small, modestly priced JBL bluetooth speaker for my son. The bass response on that thing is insane! I find listening to it so frustrating because I think about how much time and effort I've spent chasing that very tone! Argh! ... and what are they, 2" speakers at best!?
I also know Phil Jones produces amps with 7" speakers that have been reported to make some angels weep.
Put it this way, if Harry Potter played bass, cab design might make a lot more sense.
Welcome to TB @ColoradoRex
Horses for courses...
A 356 Porsche beats the paint off its contemporary V8s on the short-course twisties,
The Big Three's V8s trounced the little Porsches on big wide open road courses.
Either of those types of race cars above suck if you need to haul 40+ people — then a double-decker reigns supreme.
If bigger was simply better for bass tone, then we would've grown those 18" Foldback horns of the mid-'70s to a minimum 40" foldback by now. How many kids playing bass these days have even heard an 18" foldback? Any foldback?
Anyway, there are many schools of thought that will vie for your attention and allegiance: Vertical-array punters, ol'school fridge holdouts, in-ears adopters, and many others...
I hope you find what works for you, quickly. Good luck!
Horses for courses...
A 356 Porsche beats the paint off its contemporary V8s on the short-course twisties,
The Big Three's V8s trounced the little Porsches on big wide open road courses.
Either of those types of race cars above suck if you need to haul 40+ people — then a double-decker reigns supreme.
If bigger was simply better for bass tone, then we would've grown those 18" Foldback horns of the mid-'70s to a minimum 40" foldback by now. How many kids playing bass these days have even heard an 18" foldback? Any foldback?
Anyway, there are many schools of thought that will vie for your attention and allegiance: Vertical-array punters, ol'school fridge holdouts, in-ears adopters, and many others...
I hope you find what works for you, quickly. Good luck!
”for”
a lot of people say “better” instead of “better for” and fail to continue the thought.
a single 115 with one or another type of cabinet voicing under an amp with one or another type of non-SVT voicing that can deliver as many watts at a certain amount of ohms as that one voice coil can handle will be better for certain music genres in certain sized/shaped rooms than a pair of 810s being driven by an SVT.
There are some genres & “room” types for which any 300w SS amp driving any single 410 will be just plain insufficient and a 1,200w power amp driving a pair of Fearless F215 cabs is the better option.
Conventional wisdom says you get your mids and highs from 10” drivers, and your lows from 15” or 18” drivers. 12” drivers are a compromise.
As is so often the case, “conventional wisdom” in this case is pure BS. Multiple small drivers function together as an array to provide the performance of larger drivers. How the driver is made is much more important than its size in terms of sound.
As is so often the case, “conventional wisdom” in this case is pure BS. Multiple small drivers function together as an array to provide the performance of larger drivers. How the driver is made is much more important than its size in terms of sound.
I love the sound of a 4x10, but like people said... judge with your own ears as to what you like.
It doesn't make me wonder cause the term radiation impedance is unfortunatelly quite rarely discussed in forum discussions.
Here you are with an explanation in "easy understinding words" about the meaning of acoustic radiation impedance.
Acoustic radiation impedance - TestHiFi
Here you are with a more scientific reflection about the term acoustic radiation impedance.
Invalid Link Removed
SPL is the derivative of sound particle velocity rather than total moved air volume. Moved air volume is often identified as reactive acoustical power that does not contribute to SPL.
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you missed the many threads/pages of discussion on the subject, right here on TB, all these years!
search the subject (probably best to search on google for TB discussions) and have a field day! welcome to talkbass/TB and let's hope you don't miss out on the answers to your query!
You are missing the fact that the size of the drivers does not make the sound. The amount of air moved makes the sound. so it depends on the movement of the cone not the size. An even bigger factor is the design of the cab. A correctly tuned cab will make a better sound than a poorly designed cab. There are a dozen parameters and the circumference of the driver is only one of many.
Wasn’t that your answer for the guy looking for a practice combo in a different thread?
The tone from speaker size is a bit subjective. 10's in my experience seem to be a little more tighter and higher end whereas 15's can be a bit more "loose" and low end. It all depends and there are obviously different manufacturers of speakers so no two will be the same between two different manufacturers. I have a personal love for 10's and 12's however again to each their own. More speakers sure will move some more air but again it depends. Bigger does not always equal better either.
I'm thinking an 18" speaker would be harder to find a replacement, or service parts ffor recone when the time comes. A 12" and 10" are found more frequently these days use 2X12 or 2X10 or other multiple config to displace more air.
Also speakers with neodymium magnet structures will give the same and in some cases better performance than conventional magnets and weigh much less. That is where a *real advantage* can be had.
Do you mean dispersion? Impedance is resistive (current opposing) reactance to an alternating voltage such as the sound signal fed to the speaker. Momentary impedance will vary depending on the frequencies of the sine or other wave fed through the speaker voice coil. ...At least that is how I understand it.
The acoustic impedance for free air is given as:
Z0 = 413 N·s/m³ at 20° C
While (to the contrary) radiation impedance tells something about the (in general frequency-dependent) efficiency of a given acoustical source that induces SPL into the free air environment.
For ported cabs the Helmholtz resonator helps to improve the acoustic radiation impedance of the loaded speaker inside the cab.
In the range the tuning frequency of the cab the movement of the speaker cone becomes very small cause the Helmholtz resonator contributes effectively to the radiation impedance.
At tuning frequency there is only little air volume moved by the speaker cone yet plenty of SPL induced into the free air environment
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The general sentiment is that smaller speakers sound tighter and larger speakers sound looser/warmer but that's only really applicable in the exact same cab, tuned the same way, with the same style woofer. 12in woofers seem to be the favorite these days because they're a good middle ground.
