Double Bass How to read cabinet statistics?

[Ben Rolston]

I'm in the midst of comparing and contrasting a few cabinets, but feel a bit lost knowing what the numbers actually mean. Curious to hear people's thoughts and guidance about this topic. I'm specifically curious about comparing sensitivity, SPL, and frequency response -- and how people measure these things. Obviously hearing them in real life is most important, ideally in direct contrast.

Background info:
I had both a powered MAS 18 and 16, but realized that what I actually need is somewhere in between weight-wise. Additionally there's been a few instances where I really missed having an amp head at home. I owned a Wizzy 10 before, so I'm not really considering it but its interesting to look at the numbers.

I've been looking at:

AI DoubleShot:
12in D x 11in W
15 lbs.
Frequency response: 40 to 16kHz
Power rating: 600W
Max SPL: 118 db / 1m
Impedance: 4 ohms

Barefaced One10T:
15" x 11.5" x 11"
Cloth 8kg / 17lbs
Broadband sensitivity 95dB
Max output ~119dB
Frequency range 30Hz - 20kHz
Nominal impedance 8 ohms

EA Whizzy 10
Frequency Response: 45Hz to 5.5KHz
Sensitivity: 102dB @ 1m
Sound Pressure Level: 126dB @ 1m
Power Handling: 250 watts
Impedance: 4 ohm
Size: 15.5"H x 12.5"W x 11.5"D
Weight: 17.8 lbs

 

[JBarz]

I’ve been cabinet ‘window shopping’ and have narrowed it down to the same three, coincidentally. Eager to follow this thread!

 

[Francois Blais]

What the numbers don't tell you, is how colored is the sound.
And that's probably the most important factor to me.

 

[Ben Rolston]

What the numbers don't tell you, is how colored is the sound.
And that's probably the most important factor to me.

Indeed! The whizzy 10 is so mid-forward, maybe thats why its SPL measures higher?

 

[Francois Blais]

I have a Wizzy 10 too.
The solution for me was to replace the driver.
First tried an Eminence Beta 10A.
Better but still left to be desired.
Then got a Kappa-Pro-10A, which is much better.

 

[lurk]

I've never owned any of these, but I've heard others playing them. I like the doubleshot. The friend who has one doubles on 6 string electric bass, and it handles that low B, FWIW.

 

[flatback]

Not a big fan of the Wizzy 10 for upright. Way too mid-y and brittle sounding.Interested in the double shot though

 

[Ric Vice]

The only reason I used to look at cabinet statistics was to see if they were 8 or 4 ohm, was when I intended to use them in pairs, because smaller cabinets were easier to load in and transport.

Once I started using powered cabinets like the MAS 1/8 and 4x5.5 that stopped being and issue. It's just easier to pick the right sized cabinet for the gig and use that one. The Doubleshot is the lightest

2x10 (at least I think it is) out there. I like MAS cabinets and since I own 3 the Double Shot just isn't on my radar. These days I'm selling off gear cause gigs are few and far between at present.

 

[N. Kentucky Bass]

I've owned Barefaced Big Baby II and Super Midget. Both sounded very clear and transparent -- good for double bass or electric bass. I have not owned or played the One10 but based on what others have said, it is slightly colored and may be better for electric bass. Now there's a statistics-free opinion for you. Free!

 

[Wasnex]

Max SPL of 118dB is pretty low. There are many situations where this SPL would be useful, but also many situations where you would not be loud enough to keep up with the drums.

Sensitivity ratings are typically expressed at 1W/1m. In other words one watt is applied, and the output is measured at a distance of one meter.

Some companies post 2.83V/1m Sensitivity ratings. Personally I think this is used in a deceptive manner. Here's the deal: 2.83V at 8 ohms results in 1W and 2.83V at 4 ohms results in 2W. Why is this done? 4 ohm speakers are often slightly less efficient than their 8 ohm counterparts. So IMHO this is a way to hide this disadvantage.

Here's a rule to keep in mind. When power is doubled you get +3dB. Likewise when power is cut in half you get -3dB. Using this rule you can convert your 2.83V/1m at 4 ohm sensitivity rating to 1W/1m by simply subtracting 3dB. In other words you are converting the 2.83V at 4 ohms rating, which equals 2W, to 1W.

For example let's say you have a drivers rated for 96dB 2.83V/1m at 8 ohms, and 98dB 2.83V/1m at 4 ohms. Nothing is needed to convert the rating for the 8 ohm cab...it's simply 96dB 1W/1m. With the 4 ohm driver you need to subtract 3dB to convert to the 1W equivalent rating. So 98-3=95dB 1W/1m

Hopefully you see how this can be misleading. With the 2.83V rating it appears the 4 ohm driver is more efficient than the 8 ohm driver. With the 1W rating you see the 4 ohm driver is slightly less efficient.

Why this matters? Solid state amps frequently have a minimum impedance rating of 4 ohms. Also, amps tend to make more power at 4 ohms than 8 ohm. Because of this it can seem logical to buy a 4 ohm speaker to get maximum power out of your amp. But if you do the calculations you may find the actually difference in SPL is only about 1dB. Here's another rule: To hear an audible change in volume, you need a 3dB change in SPL.

Under many circumstances it's a better solution to buy an 8 ohm cab; then if you need more volume later, you can add an identical 8 ohm cab. Doubling the speakers increases the 1W sensitivity rating by 3dB due to something called mutual coupling. Also the affects of mutual coupling give you up to +6dB of SPL if you have enough power to push the cabs to their max volume.

 

[Ben Rolston]

This is helpful info @Wasnex ! I've seen the power x2 = +3db before, but the extra context is great.

I've sort of got the feeling that I like 4ohm cabinets more than 8ohm, but not for the volume. The section marked "Power Damping: on Page 8 from the Mesa TT-800 manual describes the feeling but I don't know if its actually applicable to this situation.

https://mesa-boogie.imgix.net/media/User Manuals/Subway-TT800-web.pdf

 

[Wasnex]

This is helpful info @Wasnex ! I've seen the power x2 = +3db before, but the extra context is great.

I've sort of got the feeling that I like 4ohm cabinets more than 8ohm, but not for the volume. The section marked "Power Damping: on Page 8 from the Mesa TT-800 manual describes the feeling but I don't know if its actually applicable to this situation.

https://mesa-boogie.imgix.net/media/User Manuals/Subway-TT800-web.pdf

AFAIK, the perceivable effect of damping depends more on the design of the amp than the impedance of the speaker. The last paragraph for the section of the TT800 manual you referenced says: "The damping factor...remains relatively constant no matter what the speaker loud is." So with this amp, I doubt you would hear much of a difference in damping simply by switching between 4 and 8 ohms cabs that are identical other than the impedance.

I believe whether a speaker sounds/feels tight and controlled or loose and bloomy relates considerably to how the port is tuned. The Thiele/Small parameters of the driver are significant factors that effect the tuning. The cab and driver must be designed to work together. I believe this articles will give you an idea of what I am trying to say: Thiele / Small parameters explained with real world cases (audiojudgement.com).

This stuff is pretty complicated...best thing to do, if you can, is audition a bunch of speakers and then choose the one the gives the performance you like. Gaining a basic understanding of what the specs means helps narrow down your potential choices, but actually trying the cab with your bass and amp is the ultimate test.

 

[juusokasperi]

Has anyone had the chance to try the One10T, preferably with both a pickup and a microphone setup? I'm currently thinking about getting another Barefaced cab to use together with the One10 (tweeterless) I have and I'm curious about the new tweeter edition. My thought it that maybe with the tweeter the sound will be a bit more natural and crisp, which might be nice when using a microphone into the amp. Torn between the Super Midget and the One10T now..

 

[Ben Rolston]

I did try the One10T, sounded great but still like an electric bass cab to me. I ended up going with the AI doubleshot instead. BUT if you like your One10 already (sounds like you do) and just want a bit more sparkle it'll be good for that.

 

[brianrost]

Both the sensitivity (i.e. 1w/1m) and max SPL can tell you roughly the same thing: how much extra power you will need to get a less efficient cabinet as loud as a more efficient one.

Simple case would be cab A is 95dB at 1w/1m and cab B is 101dB at 1w/1m. You would need four times the wattage to drive cab A as loud as cab B. If that is more power than cab A can handle, cab B will be capable of a greater max SPL.

None of this tells you anything about what the cabs sound like, because the senstivity is almost always measured at 1kHz, not over the full frequency range.

 

[notabene]

The most important spec. for the Barefaced One10 is its weight. It is a joy to carry. Sounds about as good as the EU for me.

 

[bassdude51]

I'm no expert so I only have a few basics to mention. There seems to be a trade-off with high efficiency speakers and low efficiency speakers. Lower SPL seem to have a richer and truer bass but require more watts to produce volume.

High efficiency speakers are louder (less wattage needed) but the bass response can be diminished compare the low SPL. GENERALLY SPEAKING!

Finally, frequency response. Especially low end. 30 hz? 41 hz?........+ or - what db? Minus -3 db? Minus -6 db? If the volume is not there for those low frequencies (41 hz or 30 hz) then the volume will be diminished on that low end.

Sounds overly simple................."listen to cabs before you buy"! "Let your ears be your guide"!