Upgrade my 2xTempests?

[SVO]

Hello,
I have a well-sorted IB 2-Tempests sub that I have been happy with for 4 years (60 cubic feet crawlspace, 2200 cu. ft. room). But those SPX drivers are tempting. What do folks think I would gain by upgrading drivers and/or amplification (currently running an old Carver 150 WPC)? The original tempest sounds "quick" to my ear. The new drivers are much more massively built with heavy, stiffer surrounds. Would I lose some of that snap possibly? Also, it seems odd that people buy massive amps for IB. I mean, in most installations you can bottom nearly any driver pretty easily. Are boys just buying toys or are some of the drivers so inefficient they actually need that power?

Cheers,
JD

[Darren]

I think you'd gain quite a bit by upgrading your amp. I'm not sure of the new Tempest specs though. I have 1,500 watts going to 4 RLP-15's and I cannot bottom them out no matter how hard I try. The amp gives up first. When I had a single vented Tempest I ran 250 watts to it and it performed well. I'd suggest going to 1000 watts or more and just keep the gain in check, that way if you decide to add 2 more drivers in the future you are covered. Going with a bigger amp will gain you significant headroom and you drivers will perform well. I'm willing to bet you haven't heard nearly what those drivers can do in an IB with only 150 watts.

[Kevin Haskins]

SVO wrote:

Hello,
The new drivers are much more massively built with heavy, stiffer surrounds. Would I lose some of that snap possibly? Also, it seems odd that people buy massive amps for IB. I mean, in most installations you can bottom nearly any driver pretty easily. Are boys just buying toys or are some of the drivers so inefficient they actually need that power?

Cheers,
JD

The surround is looser than the old Tempest. The Cms is a measure of the "stiffness" of the surround and in the new Tempest it had to be looser because the Mms is lighter. It doesn't really have anything to do with the sound quality though, its more a factor in choosing a set of parameters that meet a design goal in terms of what kind of box the driver will work in.

How much power you need is dependent upon two factors. First, the efficiency of the system, which is a combination of the Mms & the BL product of the driver. The new Tempest-X isn't any more or less efficient than the old Tempest. The same power will net you about the same output (pretty close at least).

The second factor is how much output you need and how much usable stroke is available. The new Tempest-X can use more power simply because it has more usable stroke. Same efficiency as the old driver but there is more output available if you have the power to take advantage of it.

[SVO]

Thanks guys. I didn't find a CMs spec for them, but the old Tempests are listed as 2 dB more efficient (not a big difference) and much smaller Xmax (obviously). The airspace is about 60 cu. ft. and the room about 2200 (dedicated, sound insulated), so on the small side. I do not use any boost in the PEQ set-up, FYI. Any other opinions welcome.

[Owen Bartley]

I'm kinda with Darren on this one. If you upgrade your amp, you may get yourself some more punch without having to do the drivers as well. And in that scenario you certainly won't LOSE any of the good sound you have now. On the other hand, if you do decide to upgrade the drivers you'll definitely need more power, so this could always be a "first step".