Any DIY Tempest owners? (1 Viewer)

[Allen Ross]

so what are you going to do with your other enclousre?

 

[Kevin_Johnson]

I really don't know yet what I'll do with the sealed enclosure. I was hoping to talk the jazz loving friend into buying it. He's definitely interested in adding a sub to his system now, but I think I made a mistake and got him liking the ported one. I may end up having to build another one of those. I suppose if anyone is seriously interested I'd be willing to sell it. I'm in Nebraska, so I don't know how shipping would go.

 

[PaulDF]

For movies, my Tempest is phenomenal. It's in a 12.5 ft^3 box lurking in the front corner of my room. Some people mistake it for a shiny black refrigerator! When watching a bass heavy movie, it'll shake my couch, and even make my hair tingle. Thats at a distance of 14 feet away!

For music, it fills in a lot, but does lack in chest pounding bass. For my musical taste, a smaller box would have been better suited.

I also tend to look for the action and bass booming movies, I think that must be pretty common, it gets the adrenaline pumping.

 

[GeorgeS]

"I have the 122L sealed tempest per Adire's instructions and it sounds fabulous. [...] No real extension below about 30Hz in my room"

maybe yours is a huge room but mine's 4000+cuft with adjacent spaces and its solid well below 20Hz

how?

BFD

 

[Ronnie Ferrell]

[QUOTE"I have the 122L sealed tempest per Adire's instructions and it sounds fabulous. [...] No real extension below about 30Hz in my room"

maybe yours is a huge room but mine's 4000+cuft with adjacent spaces and its solid well below 20Hz

how?

BFD
[/quote]

That's what I wanted to here!!! Just got my BDF on Wednesday and am going to hook it up to my 122L sealed tempest this weekend!


Ronnie

 

[Aaron_Smith]

My room is about 5600 cu.ft. and opens into other rooms. I can't be completely sure that I don't get bass below 30 Hz; the Rat Shack SPL doesn't measure that low and it's hard to really hear it, so I could be mistaken.
I wouldn't say that I am at all unhappy with the sealed sub... it is plenty loud and plenty deep. I'm curious to hear how things work out with the BFD, but I am happy enough with the current situation and probably won't even bother. I considered adding bass boost to the PE amp but chose the 24 db/oct. rolloff instead and am very happy with that mod.

 

[Ronnie Ferrell]

I considered adding bass boost to the PE amp but chose the 24 db/oct. rolloff instead and am very happy with that mod.

Good to hear that too! I am also considering it. Right now I am using both my amps x-over and my plate amps x-over to double up the roll-off slope, both set to 60Hz. Works pretty well with my system.


Ronnie

 

[GeorgeS]

"plenty loud and plenty deep"

If you're happy with it, your set. I bought the BFD because I had a huge room mode around 36hz that I wanted to tame. Pushing it ultra-low is nice for HT, but it's definitely working a lot harder and becomes excursion limited well below reference (but 'reference' isn't anything I care to sit around listening to anyway).

I was happy with it before, but the BFD was definitely a worhtwhile addition.

 

[DavidAM]

Thanks for all the replys. I think I will stick with the MID Q sealed box. I am curious though, what is BFD that you guys are talking about?

 

[Chris Tsutsui]

A BFD is a parametric equalizer.

The function is to "equalize" the bass in your room because people have different shaped room and different standing waves that affect the frequency response.

What the BFD does is reduce the volume of bass at specific frequencies that you can choose. By reducing the "peaks" or audible resonant frequencies that "ring" in the room, you can then flatten the response more.

One thing BFDs do not solve is the "dips" in the response or bass suckouts. That is where acoustic treatments come into play.

BFD = Behringer feedback destroyer I think which makes rack mount PE equalizers. They are about $100-200 and are popular among the bass geeks on this forum.

(Who am I kidding, I still want one)

 

[DavidAM]

That sounds pretty cool....I'll see how my sub sounds and then will get one if I need it. Thanks.

 

[GeorgeS]

"One thing BFDs do not solve is the "dips" in the response or bass suckouts. "

Not to split hairs but you can boost a dip in the response curve *if* its not a null (caused by destructive interference).

I set up my filters one at a time starting with large broad cuts, progressively reducing the gain and bandwidth for each adjustment and remeasuring each time. This can totally transform your response but may leave some dips. If they're nulls, dumping power into them will only strain your amp and your sub for no gain but you wont know for sure until you try. Throw a boost filter at each and see if it goes away. If it does, smile, if not, smile and delete the filter.

There are several excellent BFD threads in the speaker and subwoofer area. Definitely worth a search if you (rightly ) believe its not *real bass* until things start falling off the shelves...

 

[DerrickW]

DIY forum will give you more info. I've been playing lots and lots with winisd, but if you read any of my previous suggestions I take them back! At least for myself, now I'm looking more for low group delay along with the super-low response. This is because I've played some more with the various theories lately, and I believe that this is important to having the bass sound good and accurate.

One of my favorites is actually the well-known EBS alignment. For the tempest this is 340 liters tuned to 15.8Hz. This gives you a -3dB at 20Hz. This setup actually gives you a lower group delay from frequencies down to 32Hz than a sealed 0.707 Qtc tempest. Of course the group delay of only 7ms at 30Hz shoots up to 21ms by 20Hz. I guess the trade off is that if you really want that extra extension from 30 to 20Hz, then it isn't going to be as clean sounding. But the frequencies above 30Hz compete well with an overdamped sealed subwoofer for "tightness."

Of course this "audiophile" type of alignment doesn't give you the midrange boost of more boomy alignments. But realistically you're only talking about 1-2dB, and (IMO) if that's really the deciding factor then you may as well get multiple tempests, more power, or another sub altogether.

Best of luck.