Sub

[WmAx]

Cool stuff Greg. So where are you going to put that stuff?

Do you really need the DCX crossover device? I would think your denon has all the adjustments you need.

Not that I am questioning Andrew but as you have limited spaced if you don't need it then save the space and cash.

Well, the DCX will allow him to get a flat response to low frequencies. Sealed systems require EQ to get flat and extended response curves. Also, the DCX would be ideally used to cross the mains AND the sub(s). But I don't know if he will use it for that. The DCX can also be used as a dynamic protection system if he wants to use the dynamic EQ system to limit maximum output to specific frequency band(s). Of course, the driver will barely surpass 50% of it's linear xmax since he only has 2000 watts available to power it with. He is not able to power this driver anywhere near it's limit(s).

-Chris

 

[ParadigmDawg]

Mine is a v.2.

I understand what you are saying but I am more of a "proof is in the pudding type of guy" who wonders how all this applies in real world applications. If we are taking all these powerful subs, sticking them in rooms and having to turn then down to 1/4 of what they will put out in order for them to blend with our mains then what is the point of having a sub with more output?

The Servo 15a certainly did not impress.
http://www.avtalk.co.uk/forum/index.php?t=msg&th=18353&start=0&rid=14&SQ=1147288271

The Servo .v2 is better, but still no match to what you can expect from an AXIS-15 driven by 2000 watts in a 5 cubic sealed enclosure.
http://www.hometheaterhifi.com/volume_12_3/paradigm-servo-15-subwoofer-7-2005-part-1.html

Pay attention to the compression occurring as excursion becomes high at 25Hz and under.

Let's examine an inferior TC Sounds driver; I mean inferior to the AXIS 15 you acquired. But clearly superior to the driver used by Paradigm. Powered by a Tapco 2400 - which is similar the EP2500 - it is obvoius that the only limits in this test were due to the amp. The amp is starting to clip at the highest levels, and virtually no compression is visible due to the driver. The Servo 15 .v2's motor appears to quickly lose BL as excursion nears high levels(note the exponential reduction comparing SPL increment steps in output as frequency lowers), where the TC Sound driver is remaining constant, seemingly only limited by the amp driving it. You could easily use a 4000 watt amplifier on these TC Sound drivers. It is also possible that the exponential reduction at lower frequencies on the Servo 15 is due to factory included limiting system to protect the driver. But even so, the end result has the same likely meaning: the driver is not able to physically operate near the level of the TC Sounds unit (without suffering damage/failure).

http://www.hometheatershack.com/forums/subwoofer-tests/5759-diy-tc-sounds-tc-2000-15-sealed-90l.html

-Chris

 

[ParadigmDawg]

I still have no idea where I will put everything. I may have to run it to a closet since it's kind of ugly.

I am trusting Andrew and Chris on the need of it. Since I am doing this, I want to go all out on it (except for the fact that I am not going to spend 1k+ on amps).

Save cash...what does that mean...I can always make more money

Cool stuff Greg. So where are you going to put that stuff?

Do you really need the DCX crossover device? I would think your denon has all the adjustments you need.

Not that I am questioning Andrew but as you have limited spaced if you don't need it then save the space and cash.

 

[WmAx]

Mine is a v.2.

I understand what you are saying but I am more of a "proof is in the pudding type of guy" who wonders how all this applies in real world applications. If we are taking all these powerful subs, sticking them in rooms and having to turn then down to 1/4 of what they will put out in order for them to blend with our mains then what is the point of having a sub with more output?

If you are not using even the Servo 15 near it's limits where it start to distort or compress to an audible degree, and if you EQ it the same as the AXIS15, and you place both in the same position(would require a large turntable type device) then there would be no audible difference in a blinded test. There are a lot of IFs in there, but if you can meet the qualifications of all of them, then there is your answer.

-Chris

 

[ParadigmDawg]

Well, in my case I am trying to pressurize a 8,000 cubic ft room and I like to play loud so I need more output. I am just wondering why one would need to do this in a normal size room.

If you are not using even the Servo 15 near it's limits where it start to distort or compress to an audible degree, and if you EQ it the same as the AXIS15, and you place both in the same position(would require a large turntable type device) then there would be no audible difference in a blinded test. There are a lot of IFs in there, but if you can meet the qualifications of all of them, then there is your answer.

-Chris

 

[mike c]

Well, in my case I am trying to pressurize a 8,000 cubic ft room and I like to play loud so I need more output. I am just wondering why one would need to do this in a normal size room.

servo 15 in an 8k room?

you NEED two Axis 15's ... buy a second one and make some more money.

 

[croseiv]

Wow Greg! You definitely need more sub for that cubic footage!

 

[ParadigmDawg]

That's why I am saying the Servo holds it own pretty darn well. Andrew has heard it in action.QUOTE=mike c;497494]servo 15 in an 8k room?

you NEED two Axis 15's ... buy a second one and make some more money. [/QUOTE]

 

[ParadigmDawg]

Should be able to post some build pictures of the box later tonight....

my red crayon is showing again...

 

[WmAx]

Well, in my case I am trying to pressurize a 8,000 cubic ft room and I like to play loud so I need more output. I am just wondering why one would need to do this in a normal size room.

Well, in your case, I presume you are straining the hell out of that poor Servo 15.

The AXIS will be a far more capable device, and even then, you are amp limited, not driver limited in your case, using only 2000 watts to drive the AXIS.

As for use in normal size rooms... you got me... I don't know. But I am going to use 2 x AXIS 15" units in my 1800 cubic foot listening room; each powered by a bridged EP2500 on it's own 20A circuit. Why not?

-Chris

 

[ParadigmDawg]

I am going to wait until Andrew brings my sub over and then show him my other 3 AXIS subs and tell him I decided to go IB and he has to start all over.

 

[WmAx]

I am going to wait until Andrew brings my sub over and then show him my other 3 AXIS subs and tell him I decided to go IB and he has to start all over.

Please note, IB, to be done right, needs to have a special high mass mounting system/baffle built that is physically decoupled with a very low Fs of the suspended joint, but air tight, in relation to the main house wood framing structure, in order to minimize resonance of the structure. Few do it correctly. Obviously, if your structure that the woofers will be mounted to is masonry or other high strength construction, then such mechanism need not be used. Another problem with IB is that you have fixed locations for the subwoofers. You need to have the room response modeled by appropriate sophisticated software before hand to predict the best locations for the drivers since you will not have the option of physically moving them as you do with normal in-room cabinets.

-Chris

 

[adk highlander]

Chris, Man you know your stuff but, common you have to know when P-dawg is cranking you up.

I can see it now.

Greg says "Hi honey I decided that these puny box subs are just not enough. I'm going ot use our living room as an enclosure and mount this 18" driver in that wall".

 

[Warpdrv]

IB when implemented properly can really deliver, but there are so many variables that usually go unanswered and overlooked. I personally like the controlled scenario of a box - be it sealed or ported....

Greg, I know you mentioned it, but when is the arrival of your new baby...?

I have a TC-3000 Titanium cone on the way which I'm am looking forward to, but I am curious and wary of the prominent inductance hump in the 40-50hz range (same as the Axis), which can easily be EQ'd which I will be posting my own measurements.

I know Andrew will be running REW, can you guys post your measurements before and after. I would love to see the results.... I'm sure others would as well, it will make for a great incite to people here...

 

[WmAx]

That's why I am saying the Servo holds it own pretty darn well. Andrew has heard it in action.QUOTE=mike c;497494]servo 15 in an 8k room?

you NEED two Axis 15's ... buy a second one and make some more money.

[/QUOTE]

Andrew has the Infinity Kappa Perfect VQ 12" in the ported cabinet system I outlined and built to my specs; it easily outperforms the Servo 15 v.2 as I'm sure he will tell you. The AXIS 15 even in sealed, is going to substantially outperform the Perfect in the ported system at most frequencies - though centered at 20Hz the Axis and Perfect are pretty close, as this is a transition point where the sealed enclosure has low potential output, but that's relative.

-Chris

 

[ParadigmDawg]

Andrew has been hard at work as he complains about how cold it is outside.

 

[AcuDefTechGuy]

Looking pretty good.

Just don't forget to play that Shockwave scene in Transformers blu-ray.

 

[Matt34]

That driver is just MASSIVE!!

 

[Warpdrv]

Looks great.... that will be a fantastic sub, good bracing there, should be plenty solid...

Can't wait to see more, keep the pics coming buddy...

 

[ParadigmDawg]

I think Andrew is frozen in his garage, I may have to run over there and pour some hot water on him and see if he comes back to life.

My amp and EQ should be here today.

Looks great.... that will be a fantastic sub, good bracing there, should be plenty solid...

Can't wait to see more, keep the pics coming buddy...