High efficiency 15 in tuba ht

[NickH]

I was wondering about using a high efficiency pro driver on the tuba ht build. A driver with very low q, say less then .25 Am I correct in thinking that since it is horn loaded the fs of the driver doesn’t matter as much in this application?
The driver in questions is a precision devices pd.1551nr1. It has a fs of 37 but has a relatively high ebp. Would it still produce output around 20hz. I’m looking for the efficiency at the lower output.
The specs on the driver are as follows
Fs 37
Qms 6.1
Qes .237
Qts.228
Vas 140
X max 12mm
Ref eff 2.77
Ebp 156

I’m just wondering how this driver will perform in the cabinet since most other drivers talked about are just normal high excision sub drivers.

Thanks,
Nick

[Seth]

Hi Nick. Do you have the plans yet? The required parameters and a list of several known acceptable drivers are listed in the plans. It's super common for people to want to use other drivers that aren't the one's listed in the plans, so you're not alone. My advice would be to start with and use the least expensive "recommended" driver in the plans, listen to it for a while, and swap out for something different if at that point you feel you need to... which I doubt you will.

[NickH]

Yes I have the plans. I bought them years ago. I just want to know what effect having a driver with a higher fs will do to the output.

Thanks
Nick

[Bruce Weldy]

Check the plans.....I don't know that the driver you listed will fit. Over 7 inches in depth.

[Bill Fitzmaurice]

The combination of higher Fs and lower Qes will kill the low end. There's nothing to be gained using a pro-sound driver in the THT, and much to be lost. The PD.1551nr1 isn't sub worthy, in any cab.

[NickH]

Thank you sir.