I just built the box for my tempest today.
The box specs are 4 ft^3 sealed stuffed with 32oz polyfill. My old setup was a JL Audio 10W7 in 1.5 ft^3 ported tuned to 33hz. Both are driven with a JL Audio 500/1.
My problems with the 10W7 were basically that I couldn't get the combination of SPL and SQ that I wanted out of it no matter what box or location it was in. This would be acceptable for a lesser driver but this is supposed to be one of the best and I expected more out of the $400 that I paid. It ended up that I had to clip the signal to the W7 to get the SPL that I wanted out of the setup and that wasn't acceptable to me.
I put the Tempest in my car and ran some sine waves to it. I tuned the amp to put out 54 volts at my "loud" listening position (40/50 on the HU). 54 volts is the max unclipped signal the 500/1 can put out and stay under 1% THD. I verified all of these numbers with a Fluke 43 Power Quality Analyzer. This equates to roughly 729 watts to the Tempest with the dual 8 ohm voice coils in parallel.
Some pics of both boxes and drivers are below.
New VS Old
Closer Up
Internal Box Bracing
Altogether the speaker and the box weigh 81 lbs.
So how does it sound you ask?
Well my first impression was the SQ was exactly the same as what I was getting out of my W7, actually I liked it a little better. It had a much flatter response without the low-end dropoff that I'm used to. The Tempest is just as loud at 24 hz as it is at 35 hz, and to me this was SEVERELY lacking in the W7 in both sealed and ported applications.
The SPL was about the same to me. Considering I was feeding my W7 almost a square wave at 70 volts RMS I am much happier about the quality of the SPL that I'm getting with the Tempest. I also noticed the Tempest had much greater impact accuracy than my W7 did. My W7 seemed pretty sloppy at things like double bass but the Tempest does it much, much better.
I'm sure that I could do better with a 13W7 than my 10W7 but in all honesty I don't see the point of spending about 5x as much when I can get the sound quality and SPL that I really like out of one $150 driver.
When I get some more money I plan on putting a Brahma 15" in the same box and filling it with some wooden blocks to lower the internal volume, but that isn't for a while.
The box specs are 4 ft^3 sealed stuffed with 32oz polyfill. My old setup was a JL Audio 10W7 in 1.5 ft^3 ported tuned to 33hz. Both are driven with a JL Audio 500/1.
My problems with the 10W7 were basically that I couldn't get the combination of SPL and SQ that I wanted out of it no matter what box or location it was in. This would be acceptable for a lesser driver but this is supposed to be one of the best and I expected more out of the $400 that I paid. It ended up that I had to clip the signal to the W7 to get the SPL that I wanted out of the setup and that wasn't acceptable to me.
I put the Tempest in my car and ran some sine waves to it. I tuned the amp to put out 54 volts at my "loud" listening position (40/50 on the HU). 54 volts is the max unclipped signal the 500/1 can put out and stay under 1% THD. I verified all of these numbers with a Fluke 43 Power Quality Analyzer. This equates to roughly 729 watts to the Tempest with the dual 8 ohm voice coils in parallel.
Some pics of both boxes and drivers are below.
New VS Old
Closer Up
Internal Box Bracing
Altogether the speaker and the box weigh 81 lbs.
So how does it sound you ask?
Well my first impression was the SQ was exactly the same as what I was getting out of my W7, actually I liked it a little better. It had a much flatter response without the low-end dropoff that I'm used to. The Tempest is just as loud at 24 hz as it is at 35 hz, and to me this was SEVERELY lacking in the W7 in both sealed and ported applications.
The SPL was about the same to me. Considering I was feeding my W7 almost a square wave at 70 volts RMS I am much happier about the quality of the SPL that I'm getting with the Tempest. I also noticed the Tempest had much greater impact accuracy than my W7 did. My W7 seemed pretty sloppy at things like double bass but the Tempest does it much, much better.
I'm sure that I could do better with a 13W7 than my 10W7 but in all honesty I don't see the point of spending about 5x as much when I can get the sound quality and SPL that I really like out of one $150 driver.
When I get some more money I plan on putting a Brahma 15" in the same box and filling it with some wooden blocks to lower the internal volume, but that isn't for a while.
