[ttan98]

I am thinking of using this TT Bass Boy as a bass unit in a vented enclosure. It has the following paramenters:

10" Bass Tone Tubby 8 Ohm Speaker Specs
Driver Properties
Name: TT Bass 10
Type: Standard one-way driver
Fs = 63.8 Hz
Fsa = 42.7 Hz
BWs = 81.4 Hz
Vas = 48.4 Liters
Cms = 2.82E-04 m/N
Mmd = 18.3 g
MMr = 3.76 g
BL = 11.1 Tesla/m
Eta = 2.61 %   
Qms = 1.69
Qes = 0.46
Qts = 0.36
Re = 6.400 Ohms
Zmaxs = 29.7 Ohms
2.83-V SPL = 97.1 dB
1-W SPL = 96.2 dB
Kr = 0.000
Xr = 0.000
Ki = 0.000
Xi = 0.000

Can any tell me the difference between the Fs and Fsa quoted above? What is the real resonance frequency?

Thanks in advance.

The unit only costs $105 after discount, not bad price.

[painkiller]

Where did you get those specs? I'd really like to get specs for the 15" version, but Tone Tubby seems to keep it to themselves. Wonder what the Xmax is.

Fs is the "real" resonance frequency. Fsa is the lower resonance frequency with added moving mass, which I never understood the point of.

[iON]

painkiller: TT used to have the t/s published on their website, Try archive.org.

ttan98: Fs is probably the one you'll be interrested about. (A guess would be that If they've used delta mass method to compute the t/s parameters Fsa may be the resonance frequency with added weight)

Cheers!

[ttan98]

painkiller,

the archive webpage does not include the spec for the 15".

[scorpion]

You won't get much (any) low-bass out of that element in a VB.
Bass speakers should be considered in order: IB, OB and CB and ...........

/Erling

[painkiller]

You won't get much (any) low-bass out of that element in a VB.
Bass speakers should be considered in order: IB, OB and CB and ...........

But a low Qts driver in an OB. How does that work? Perhaps one could get some bass output by placing the driver close to the floor, using side braces and perhaps some stuffing?

[scorpion]

The last sentence was meant more like a general remark of my personal preference for bass-pruduction.
This Tone Tubby bass won't do it for Hi-Fi in any kind of (non-) enclosure but will probably be OK for guitar in VB.

/Erling

[painkiller]

I'm in dialogue with A Brown about a custom 15" Super Boy for OB. They seem positive so far, but we'll see.

[painkiller]

I finally managed to get the 15" specs from A Brown.

Nom. diamerer [inch] 15   
Vas [Liters] 260   
Qts  0,3   
Qes  0,31   
Qms  13   
Fs [Hz] 43   
Sensitivity [dB] 101   
Max Power [W] 400   
Lower freq [Hz] 60   
Upper freq [Hz] 3500   
xmax [mm] 3,25   
Moving mass [g] 48   
Disp area [m2] 0,086   
xdamage [mm] 12,5   
Coil diameter [mm] 62,5   
Cms [mm/N] 0,214   
Rms [N*s/m] 1,4   
Magnet weight [gr] 2,225   
Re [ohm] 5,2   
Z [ohm] 8 

Crazy sensitivity there. A bit lower Q, and lower Fs. Any way one could make this work in an open baffle? I guess the 16 ohm version would have a bit higher Q?

[ttan98]

15" woofer has been used as mid-bass driver in an open baffle configuration before, eg being Bastani open baffle, the bass driver(15") is a separate unit driven by a solid state built-in amplifier in a sealed enclosure.

I don't know the specs of both drivers.

[dewar]

I've used Qt 0.29 12" Peerless drivers in OB and did not have the use the DEQ2496 it was running through for anything else than pulling down a peak, but this was with a 30hz room node helping out, and biamping, which makes sensitivity largely moot.

Maybe have a read of the Jamo OB whitepaper. They used lowish Q bass drivers but of much higher sensitivity than the midrange drivers and a coil on the bass drivers to achieve a net flat FR and sensitivity match, if I remember. (Havent read actual paper myself).