Seeking Subwoofer Advice

[Paducah Home Theater]

Thought I'd add a pic that shows the difference between the DIYsoundgroup MDF (bottom layer) and the stuff you get from Lowes (top two layers). The DIYsoundgroup material is a much finer and denser grade.

image.jpeg

That's double-refined cabinet grade MDF. They use it because you can run it through a router and CNC machine much better, plus when you paint it especially on the edges it doesn't suck up the paint and swell up. I used the big box stuff recently on a test project to keep the price down but it sucks comparatively. Menards actually has the good stuff for only $5 more a sheet but it's usually more like $15-$20 more a sheet and weighs about 10+ pounds more. It's also way stiffer, you can pick up the short end and across an 8' long sheet there's just hardly any flex/sag at all.

Edited July 26, 2016 by MetropolisLakeOutfitters

[fuzzydog]

 

Get the I Nuke 6000 DSP.  This will let you run one on each channel.  Wire the driver in series to 4 ohms. Your diver is 1200 RMS and will peak over 2000 watts.  A single channel of the I Nuke is good for a bit over 2000 watts at 4 ohms.  The I Nuke 3000 DSP would have to be done in bridge mode for one sub.

 

 

@derrickdj1, is the DSP version still needed if you have an advanced receiver with sub EQ?

 

Although the Behringer EP4000 doesnt have DSP, i'd read somewhere that the EP4000 rates closer to advertised power than the Inuke 6000.  

 

Thanks.

 

Just bumping my last question up since it was at the bottom of the last page...

[Paducah Home Theater]

is the DSP version still needed if you have an advanced receiver with sub EQ?

It's actually surprisingly doable, I've done it before and it sounds better than what some people would have you expect. Your rolloff on sealed subs will be steep enough that a DSP is kind of really nice to get things flat though if you're measuring. Plus you can dink with the limiters and squish any boosts from room mode issues and get it close so that Audyssey doesn't have to work so hard.

You could actually get another amp then use a MiniDSP, but they're harder to set up, they clip easier than most people think. iNuke's DSP is real easy. MiniDSP makes a balanced version that accepts higher voltage, maybe look at that, but you lose the easy RCA connections.

I wouldn't worry about power from the iNuke except for like 15 hz and below. It and every other cheap class D amp starts rolling off below 20 hz. Otherwise you would have more than enough clean power. They can bottom out an Ultimax for sure, I've done it on multiple occasions. You have a little more xmech though.

Edited July 26, 2016 by MetropolisLakeOutfitters

[babadono]

 

 

Get the I Nuke 6000 DSP.  This will let you run one on each channel.  Wire the driver in series to 4 ohms. Your diver is 1200 RMS and will peak over 2000 watts.  A single channel of the I Nuke is good for a bit over 2000 watts at 4 ohms.  The I Nuke 3000 DSP would have to be done in bridge mode for one sub.

 

 

@derrickdj1, is the DSP version still needed if you have an advanced receiver with sub EQ?

 

Although the Behringer EP4000 doesnt have DSP, i'd read somewhere that the EP4000 rates closer to advertised power than the Inuke 6000.  

 

Thanks.

 

Just bumping my last question up since it was at the bottom of the last page...

 

Cecaa850 posted a link to some real measurements in another thread, I'll try to find it.

[babadono]

yea here it is:

http://www.avsforum.com/forum/155-diy-speakers-subs/855865-measuring-amplifiers.html

no inuke though.

[fuzzydog]

no inuke though.

 

Thanks, i had seen that, but still wondered how the Inuke 6000 DSP real world power ratings compared to the EP4000's.

 

I'm eventually going to be running two sealed Stereo Integrity DS4's in 4 CF sealed cabinets.  

 

The DS4's are rated for 1200 watts so i want to make sure i'm not leaving anything on the table...especially since a 4 CF cabinet may be on the small side for this driver.  

[Paducah Home Theater]

This is the problem with the iNuke more than power in general.  iNuke fans don't like admitting there's an issue, but it is what it is.  

 

http://www.avsforum.com/forum/155-diy-speakers-subs/2100354-inuke-6000dsp-filter-mod-guide-less-low-frequency-rolloff.html

 

[fuzzydog]

This is the problem with the iNuke more than power in general.  iNuke fans don't like admitting there's an issue, but it is what it is.  

 

LOL, if i tried to do what that guy did, i'm pretty sure my house would burn down.   

[Scrappydue]

This is the problem with the iNuke more than power in general.  iNuke fans don't like admitting there's an issue, but it is what it is.  

 

http://www.avsforum.com/forum/155-diy-speakers-subs/2100354-inuke-6000dsp-filter-mod-guide-less-low-frequency-rolloff.html

 

 

i love seeing this stuff. i must have some serious room gain cause my stuff dont look like that even a LITTLE BIT

[Paducah Home Theater]

 

i love seeing this stuff. i must have some serious room gain cause my stuff dont look like that even a LITTLE BIT

 

 

That's because you're measuring the output of the subs, in a concrete bunker, probably at a not so high of output, and not what the amp itself can do.  If you were really spanking the amp and the amp was flat, you'd have nothing but clacking below 20 hz where that top/bottom plate of those HT-18's is getting smacked.  

 

But yes, as for room gain, class D amps have a stated 6 db per octave negative slope while room gain is usually estimated at a 12 db per octave positive slope below the calculated point where it starts.  Very possible for room gain to more than make up for the loss, at least for awhile until the power supply starts crapping out.  Which it will sooner or later.  

Edited July 27, 2016 by MetropolisLakeOutfitters

[derrickdj1]

Sure you can mod the DSP and amp but, the real question do you need it.  The I Nuke is more than adquate for most people.  Most of us are not trying to get to 130 or 140 db.  I have very little gain in a 4300 cu ft. + room.  I calculated that room gain does not start until 18 Hz and the subs go down to 15 Hz-18 Hz.  I am flat to 15 Hz.  Don't look at all this stuff with a microscope or you can miss the big picture.

 

More power is not the issue.  Most drivers only have so much excursion and as long as that can be reached, no more power is needed.  Unused power is simply that.  The I Nuke is not the issue, match the appropiate amp to the driver/box size is required.

Edited July 27, 2016 by derrickdj1

[Paducah Home Theater]

I have very little gain in a 4300 cu ft. + room.  I calculated that room gain does not start until 18 Hz and the subs go down to 15 Hz-18 Hz.  I am flat to 15 Hz. 

 

You also have multiple ported subs that are tuned super low including two that are 17 cubic feet and tuned to 14.5 hz.  I don't see how you couldn't be flat to 15 hz.  

Edited July 27, 2016 by MetropolisLakeOutfitters

[derrickdj1]

 

I have very little gain in a 4300 cu ft. + room.  I calculated that room gain does not start until 18 Hz and the subs go down to 15 Hz-18 Hz.  I am flat to 15 Hz. 

 

You also have multiple ported subs that are tuned super low including two that are 17 cubic feet and tuned to 14.5 hz.  I don't see how you couldn't be flat to 15 hz.  

 

 

I was flat to 15 Hz a long time ago before the big box subs.  The I Nukes DSP has always been needed in large rooms to raise the low end.  The DSP gives you so much more control on mating the sub with the room.  This is rarely possible with your standard plate amp sub.  I just don't see a bunch of people complaining about not enough power from the I Nuke amps.

 

I know the amps have been evaluated on AVS and acknowledge there is a roll off.  The I Nuke is still the best bang for you buck.  I had the subs on Crown amps but, the Crown's could not generate the same performance of the I Nuke since they did not have the DSP/PEQ.  They cost more for less performance. IOW, the PEQ/DSP makes up for any short comings on the I Nukes.

[Paducah Home Theater]

I thought the Crown sounded the most defined for whatever reason.  Super crisp kick drums.  Possibly higher damping factor than the others but I'm not sure, may have been a setting, who knows.  It definitely suffered below 10 hz though, the power supply just couldn't hang.  They actually have a hard limiter on the power supply and it would just completely cut out.  I destroyed it trying to follow Seaton's advice on how to break them in quickly.  He said to run them for half an hour just below Fs at maybe half excursion, free-air.  That equaled a blown up Crown amp and that really wasn't even half excursion.  He's used to playing with SpeakerPower I suppose.  The Crown can't handle long term output, only short bursts.  

Edited July 28, 2016 by MetropolisLakeOutfitters

[derrickdj1]

Where you doing sine waves or something similar to keep the excursion?

[Paducah Home Theater]

Yes, non-stop sine wave for 30 minutes.  Was supposed to fast track the break-in period and do the same as if you had 100 hours of real world use on them.  Apparently it's fairly common.  Ricci does something similar before every test.  

Edited July 28, 2016 by MetropolisLakeOutfitters

[derrickdj1]

I know some people believe in breaking in the sub.  I just run them and re-calibrate the system at the end of the first month and then the second month.  I fooled around with sine waves but, stopped after given a stern caution by a Klipsch forum member.  The driver needs to move to keep the VC from getting to hot.  A hot VC increases resistance and makes the amp work harder.  End result, damage the driver or amp.

 

I may have had a hand in one of the I Nukes that I sent for repair to Berhinger.  Now, high spl with only Omnimic short sinewaves.

Edited July 28, 2016 by derrickdj1

[Paducah Home Theater]

I know some people believe in breaking in the sub.

 

Changes are measurable even on normal speakers.  Serious subs are especially bad though.  Super stiff spiders and surrounds make for some muffled upper extension until they loosen up.  For LFE down low it just doesn't matter much, just a matter of slightly less SPL.  

Edited July 28, 2016 by MetropolisLakeOutfitters

[RoboKlipsch]

On Tuesday, July 26, 2016 at 2:18 PM, FuzzyDog said:

 

Thanks, i had seen that, but still wondered how the Inuke 6000 DSP real world power ratings compared to the EP4000's.

 

I'm eventually going to be running two sealed Stereo Integrity DS4's in 4 CF sealed cabinets.  

 

The DS4's are rated for 1200 watts so i want to make sure i'm not leaving anything on the table...especially since a 4 CF cabinet may be on the small side for this driver.  

I went through this thought process too.  I got the 6000dsp.  Understand that your basic level of sub output comes from the first watt.  With ds4 u get say 88db at 1meter.  Double watts to 2 for 3db boost.  Then double to 4 for next 3db....and so on.  Do the math u see at some point you run out of doubles....at a wattage beyond the ds4s capability.  On the low end excursion is a factor.  Sounds crazy but 1000 watts or 2000 watts is not that important.  DSP is.    In a room under 5000ft3 2 ds4s sealed will be awesome.  When u need more u add anothet sub....but u wont need it for spl.

[fuzzydog]

Progress report...almost done with the veneering.