Home Theater Forum and Systems banner

1 - 14 of 14 Posts

·
Registered
Joined
·
159 Posts
Discussion Starter #1
Hi, I just finished building a 200L birch enclousure with two 18-2100 PR's. This box was for a AE AV15X sub I received a few weeks ago that got damaged. Meanwhile, I got this TC 3K 15" sub sitting around and would like to put it in that box with the PR's, at least until I get a new AV15X sub or even the new Revo (a new and hopefully improved version of the old TC 2K sub) sub coming from TC Sounds in November.

I know the TC 3K sub is a high inductance sub that works well in a small sealed box with lots of power. How will it do in the 200L box with the PR's and 1,300 amps (ED LT1300 plate amp) with ED EQ2 as the equalizer. What would the tuning for this sub be? By the way, I added some 5-lbs of polyfill to that enclousure. I know this will only be a temporary solution for a couple of months until I get one of the two choices above since the TC 3k sub is great in the low bass but somewhat lacking in the mid-bass area. I had it previously in a sealed box. Thanks.
 

·
Registered
Joined
·
2,431 Posts
What happened to the AV15?

The TC3K should be fine in that enclosure. The low end may be a little peaky, but depending on where the PR's are tuning things (???) it should be solid anywhere from a 22-15hz tune. It will laugh at the 1300w everywhere above 16hz and ask for seconds. You could use a full 2500w on that driver with the proper HPFing even with a low 16hz tune. May not be as snappy in the 50-90hz area but it should have better bottom octave 16-32hz than the AV15. GL. Post some impressions of the differences in sonic character.
 

·
Registered
Joined
·
159 Posts
Discussion Starter #3
Ricci, I just installed the TC 3K driver in the PR's enclousure and just finished running some test tones. I can say that it's flat (within 4db's) from 20hz-60hz. Even the 15hz test tone is good, only 6-7db's down
from the 50-60hz range. After 60hz, it drops quite a bit, is 6-7db's down by 70hz and 15db's by 80hz. That's with a crossover of 80hz.

The AV15X sub is much better for mid-bass (60hz-120hz), but gives up some spl below 30hz, by 15hz, is down some 4-5db's compared to the TC sub. On the other hand, the TC sub is down some 3db's to 12db's from 60hz-120hz.

My AV15X sub could not take the test tones at 20hz I did to it for several minutes to loosen up the PR's as I was told to run some material with deep bass near tuning of the sub at a good volume level. At first I thought it was the amp, but when I heard some popping noises coming from it and I took the sub out, it smelled like something had burned, probably the coil. Anyways, it's going back to AE to get checked.
I've done the same tests with the TC 3K sub with no problem. The volume of my receiver was at -5 during the tests (0 being reference). It was only tested at 20hz for 15 minutes with a rest of a few minutes every 5 minutes of tests.

Lets see what AE does, if it does not work out and I don't get another AV15X sub, then I might go for the new TC (Revo) sub coming out in a few weeks. It should (hopefully) be a better version of the old TC 2K sub and should be much more linear in its response than the TC 3K sub I have now.

The TC 3K 15" sub I have is the older version. It has the black cone and is a DVC 2ohms. I will be testing it with some movies, which were bottoming my AV 15X driver out during some heavy bass scenes. Anyways, if someone has the specs for this sub and can find out the tuning point in my enclousure, I'll apreciated. Right now, my ED EQ2 filter is set at 15hz.
 

·
Banned
Joined
·
1,074 Posts
My AV15X sub could not take the test tones at 20hz I did to it for several minutes to loosen up the PR's The volume of my receiver was at -5 during the tests (0 being reference). It was only tested at 20hz for 15 minutes with a rest of a few minutes every 5 minutes of tests.
:scratch:

free air you can do that all day.... but at tuning loaded in an enclosure??? playing sceens is 1 thing, test tones is another....
 

·
Registered
Joined
·
2,431 Posts
Wait let me get this straight...You left a 20hz sine wave playing at a high level through the subwoofer for 20minutes? :paddle: That would be a near worst case scenario for the driver. It's close to your tuning which means that the impedance is low, drawing a lot of power from the amplifier and the driver is at a point of minimal motion which means that it isn't pumping much air across the vc's and through the motor. That would fry a vc yes. The AV15 has a less massive smaller diameter vc so it is not going to handle as much power as the TC3K thermally. (It is more efficient though). It doesn't have as much clean stroke either. Don't do the 20hz sine wave beating to the TC3K too.

If you want to loosen up your PR's just use the sub. Watch a bunch of action movies. this will be much easier on the system than a sine wave.

I don't own either of these drivers, but I'd say that the TC3K is a much beefier and robust driver all around while the AV15 probably sounds a little better.

Also your enclosure PR tuning will not change. It'll be the same for any driver that you put in there. That does not mean that you will get the same overall FR, headroom, or any other aspect of performance other than the tune of the PR's.
 

·
Registered
Joined
·
159 Posts
Discussion Starter #7
Ricci, I played the test tones in 5-minute intervals x 3 = 15-minutes, with a few minutes of rest between each test. I've pushed the TC 3K just as hard with no issues. With this incident though, I won't be pushing any more subs with high volume test tones. I played some action movies at reference level and the AV15X was bottoming on some of the deepest bass scenes (the driver was making claking sounds). Can't I damage the driver by bottoming it several times? The SPL level at my seat is around 105db during the bottoming of the sub. Also, if the coil is burned, does that mean the sub is useless (can't be rebuilt)?

The AV15X sub is much better than the TC 3K sub in the mid-bass, it has the slam that the TC lacks. Music is more articulate and louder. On the other hand, I expected more in the HT department, maybe I'm been to demanding of this sub. From all the positive reviews, I expected a lot. Also, the AV15X sub's weight was only 30-lbs. I thought this sub's weight was closer to 40-lbs. I wonder if I got the right sub. The TC 3K sub is beefier, about 42-lbs and can take more abuse (much more power handling).

Even with each 15" sub's different specs, you're saying that the tuning point is going to be exactly the same? Won't there be some difference of maybe 1 to 2hz in the tuning point? Thanks.
 

·
Banned
Joined
·
1,074 Posts
Even with each 15" sub's different specs, you're saying that the tuning point is going to be exactly the same? Won't there be some difference of maybe 1 to 2hz in the tuning point? Thanks.
The enclosure with the PRs is independant of the driver. The enclosure and PRs will always have the same tuning. Every driver that you put in there will behave differently in it though, yes. It is called alignment.

However, yes, you maye gain a tiny bit of airspace or lose a tiny bit of airspace by putting different sized drivers in, but you will never hear that slight bit of tuning change...it's very minimal.
 

·
Registered
Joined
·
2,431 Posts
Hey Marce,

I've heard both subs but I haven't personally had a chance to play with them. However I think you have it right. The AV15 is just not as rugged as the TC3000 and it doesn't have as much excursion. Yes if you hard bottom'd the driver you can damage it. Also if the coils are toasty that means it was getting a large amount of heat build up in the motor. However you should be able to get it re-coned no problem. 5min or 15min of 20hz sine wave either way is very brutal on the driver in your enclosure. The most that I ever put through my drivers at high levels is about 25sec. I leave a tone playing for much longer for some sorts of tests, but it will be at a much reduced level and again this was only for tests. If you want to break something in just run music or movies through it as you would in normal use, or you can free air it as the better cooling and lower power required will be much easier on the driver.

What amp were you using on it?
 

·
Registered
Joined
·
159 Posts
Discussion Starter #10
simon5 at AE told me to run heavy bass scenes close to the sub's tuning for 10-minutes or so to break in the PR's. In the process, not only did I break the PR's, or did I? but also the sub. I learned my lesson, believe me. The power was supplied by ED LT1300 plate amp.

Anyways, I'll be testing the TC 3k and the PR's to see how they perform this weekend with some deep bass movies. John at AE was good enough that he paid the return shipping of the sub which I shipped today. So you're saying the sub (coil) can be repaired and a new sub won't be needed? I hope so because I don't want to pay for the same AV15X sub twice. I probably have to pay for the repair and return shipping but it should be cheaper than getting a new one, right?
 

·
Registered
Joined
·
159 Posts
Discussion Starter #11
I just finished playing the bass scene that bottomed out my AV15X driver on the TC 3K sub at reference level and it did not bottomed the TC driver. Both subs with the same power (ED LT1300 amp) and same size box (7cf) with PR's. The scene is when King Kong jumps in towards the end of the battle scene with the T'rex. Is is because the TC sub has more power handling and xmax? Maybe the TC sub got some help if the PR's are now "broken in" with the test tones I ran with the AV15X sub. The thing is that with the AV15X sub in this scene I got 103db's in the meter compared to 100db's with the TC sub at my seating position (12ft away) in a 6,000cf room.
 

·
Registered
Joined
·
1,633 Posts
To me it seems as though you are just realizing one sub is more suited to low bass and the other to mid-bass. You are probably expecting the AV15 to not only supply the mid-bass that you like so much but to cover the low end like the TC3K you are familiar with. Most of time there are trade-offs that need to be made when building subs. You might be better off keeping the TC3K in there and building a MBM to cover the 50 to 120hz range. This way both subs will be working in there comfort zone.

Maybe when you get the AV15X back you could try a MBM out. It doesn't appear that it is going to supply the low end you desire but it will deliver the mid-bass you crave.

Just a thought.
 

·
Registered
Joined
·
159 Posts
Discussion Starter #13
sub_crazy, you make a good point, one I've thought about before since I already have a 4cf box sealed box sitting empty. I would need to get a 500w plate amp and a crossover (behringer?) and like you said, put the AV15X sub there and use the TC 3K sub for the 50hz and below bass and let the AV sub do the mid-bass (50hz-120hz), we'll see.
 
1 - 14 of 14 Posts
Top