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post #1 of 233 Old 09-25-2012, 05:31 AM - Thread Starter
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Hi everyone!

OK, so long story short, I had an Onkyo HT-S5400, then upgraded the receiver to a 609, upgraded all my speakers, EXCEPT the sub and here we are.

Was dead set on a pre-fab sub from Lava, BIC, or Klipsch. Finally decided to go another route and build my own.

This is what I am working with:

TC Sounds Epic 12" DVC (500w RMS @ 2+2 ohms) sub
Dayton Audio SPA500 amp (540w RMS @ 4 Ohms)

Unfortunately, I have zero box building skills. My room is big too, about 35' x 17' total, kitchen and LR shared, no separating wall, ceiling that goes from 9ft up to like 15ft.

Also, I am on a limited budget. I've already purchased the amp, and I will be ordering the sub early next week.

I figured 3/4" MDF is a good place to start. I also have a fully activated copy of BassBox Pro 6.

So what's the best configuration for me? Ported, Passive Radiator, Sealed? I want to make sure my sub still can hit north of 100db at 20hz, if possible. Polyfill? Acoustic Panels? Both? How to I make the port. If using PVC, how do you sand it down to make smooth?

What tools do I need? How do I measure out a perfect circle and cut it? Things like this are making me nervous about this project...

Anyway, any advice is appreciated.

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post #2 of 233 Old 09-25-2012, 09:50 AM
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Quote:
Originally Posted by mfrey0118 View Post

...Unfortunately, I have zero box building skills. My room is big too, ...I figured 3/4" MDF is a good place to start. I also have a fully activated copy of BassBox Pro 6. ...How to I make the port. If using PVC...What tools do I need? How do I measure out a perfect circle and cut it? ....
The least challenging approach is sealed. It's also smallest, lightest, etc.. Find what size box will keep the driver within Xmax at rated amp power, and build a box that internal volume. Stuff it with low-density (fluffy) insulation or fiber fill until it sounds good. Put it in the corner with the lowest ceiliing, so you get the most efficient coupleing to the room and maximize room gain.

The most challenging (and highest performance) approach is to design a folded horn, but I suspect fabrication alone would be a sufficient barrier.

That leaves ported, and with enough room for the box, I'd second imagic's LLT. You have box design SW, so look at very large volumes and very low tunings to get an LLT. Plan to put it in the same corner as above, for maximum output.
http://www.hometheatershack.com/forums/diy-subwoofers-general-discussion/1820-llt-explained.html

MDF is a good place to start, but plan to double-up on the baffle (side with the driver), especially if you want to recess vs. surface mount the driver. The one advantage to surface mount is that no one sees the hole you cut, so a simple jig-saw is all you need, and the ability to draw a circle (needs a nail, string and pencil) and follow the line. A router and circle jig is commonly used, especially for accurate circles with crisp edges when recessing a driver.

Cutting straight side panels is important. Pay someone to do this if you don't have a good table saw, or you'll need to fill gaps on the outside and add sealant in the interior corners.

PVC makes great ports. Be sure to model with the intended pipe ID. I like to cut a recess on the inner side of the port panel and epoxy the pipe there, where there are no critical dimensions. I then complete the (undersized) through hole and trim with a router roundover bit. I get a smooth transition from MDF to PVC, a nice flare to the port mouth, and no need to worry about how well the PVC finishes as its MDF that I'm painting. Some like to cut a slip-fit through hole, then glue and route the roundover... no functional difference and paint holds well to a routed PVC surface, but you can see the seam.

Assuming ported, you'll want a layer of acoustic absorber on the walls, perhaps 1-2" thick, to damp any harmonics coming off the sub. Anything from air-permenable foams to purpose-designed materials. I use carpet underlayment foam as it's cheap and effective. No one sees what's inside, and in a sub, it's less critical than higher-frequency speakers. Add nothing but braces in the open interior space, especially between driver and port, as you want that volume to resonate, so the port has functional output.

Add cross braces at roughly 8-12" spacings. 1-1.5" hardwood dowels are easy to use and take up minium space for their effectiveness. Cut them a little short and slip some tapered shim stock (like you'd use to align a window or doorway)under when you glue them in. Some do very elaborate braces, but it's inside so audible benefit counts more than visual appeal. The braces don't need to be exactly spaced, and any that touch should be glued or separated to prevent buzzing.

Then be prepared for "room modes;" spatial variation in loudness. Above grade construction with single-layer sheetrock walls and windows/doorways can mitigate a lot of room mode issues compared with a sound-isolated room. If there are obvious issues, you do have options, but hey're more complex than I want to go into here.

Regardless, take the leap and build something. Your first project may not be your best, but it's how you learn...

HAve fun,
Frank
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post #3 of 233 Old 09-25-2012, 11:18 AM - Thread Starter
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Guys thanks so much for lending your expertise...this is good stuff...

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post #4 of 233 Old 09-25-2012, 01:30 PM
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Horn or ported.

 

As big and tuned as low as you can accomodate.

 

You'll need EQ for High Pass.

 

Corner Load

 

Sell the dayton and get a pro-amp(prefereably one with EQ) you'll not even wake up the TC with a 500W plate amp.

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post #5 of 233 Old 09-26-2012, 07:12 AM - Thread Starter
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Quote:
Originally Posted by NicksHitachi View Post

Horn or ported.

As big and tuned as low as you can accomodate.

You'll need EQ for High Pass.

Corner Load

Sell the dayton and get a pro-amp(prefereably one with EQ) you'll not even wake up the TC with a 500W plate amp.

How is this amp not waking it up?

TC Sounds Epic 12: 500w RMS
Dayton SPA500: 540w RMS

??

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post #6 of 233 Old 09-26-2012, 07:53 AM
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I just built a pair of subs (will post build log later today) but each one uses the epic 12 in 3 cubes tuned to 21 hz. They are each powered by a yung 500w plate amp. I had to go plate to please the wife. Trust me these guys are awake! They could take more power, but I know that the drivers are safe, they move alot though, crazy excursion. It's more bass than I'll ever need honestly.

Dan
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post #7 of 233 Old 09-26-2012, 08:10 AM
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Hi mfrey,

 

First off, I'm not bashing your amp.  It is a fine sub plate amp.  As always with any manufacturer take the published specs with a grain of salt.  For example since I couldn't find testing results for your exact amp, take the Dayton Flagship subwoofer amplifier HPSA1000-R. 

 

Specifications:

Measured power output: 512 watts RMS into 8 ohms @ 0.09% THD,
1,024 watts RMS into 4 ohms @ 0.15% THD
Signal to noise ratio: 98 dB (A-weighted)
Parametric EQ: Frequency: 18-80 Hz, Level: -14.5 to +6 dB, Bandwidth: .1-1 Low pass crossover: 30-200 Hz
Phase: 0-180°, continuously adjustable
Dimensions: 17-1/2" W x 4" H (2RU without feet) x 14" D
Power requirements: 110/220 VAC, 60/50 Hz
Dimensions (with feet, without rack ears): 17-1/2" W x 3-7/8" H x 14" D Dimensions (without feet, with rack ears): 19" W x 3-1/2" H x 14" D.

Actual Tested Specs:

 

High impedance specs are easier to hit and the dayton isn't far off @ 8ohms but 4ohms is almost half the published spec, nevermind these were at 40Hz and the numbers would be lower and more unstable at 20Hz since distortion is already at .33% @ 40Hz.

 

 

I would be surprised if the 500W plate amp tested above 300W true RMS output. 

 

Now, having said all that:

 

  • I only recommended another amp/pro amp with EQ since you will have to buy one(EQ) anyways and your likely underpowered.
  • Is that TC rated 500W/ coil or 500W total?
  • 86.6db sensitivity, don't leave spl on the table undershooting power requirements.
  • Modeling should help determine your power requirements as excursion will prob dominate your limitations.
  • Double the power = +3b
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post #8 of 233 Old 09-26-2012, 08:36 AM
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Big room, small sub. What I would do is maybe look for a 15" sub to use in a large ported design and tune it to around 20hz since the Dayton amp has a subsonic filter around 18-19hz in order to maximize your output where it's needed most.

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post #9 of 233 Old 09-26-2012, 02:17 PM
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Quote:
Originally Posted by NicksHitachi View Post

Hi mfrey,

First off, I'm not bashing your amp.  It is a fine sub plate amp.  As always with any manufacturer take the published specs with a grain of salt.  For example since I couldn't find testing results for your exact amp, take the Dayton Flagship subwoofer amplifier HPSA1000-R. 

Specifications:


Measured power output: 512 watts RMS into 8 ohms @ 0.09% THD,
1,024 watts RMS into 4 ohms @ 0.15% THD

Signal to noise ratio: 98 dB (A-weighted)

Parametric EQ: Frequency: 18-80 Hz, Level: -14.5 to +6 dB, Bandwidth: .1-1 Low pass crossover: 30-200 Hz

Phase: 0-180°, continuously adjustable

Dimensions: 17-1/2" W x 4" H (2RU without feet) x 14" D

Power requirements: 110/220 VAC, 60/50 Hz

Dimensions (with feet, without rack ears): 17-1/2" W x 3-7/8" H x 14" D Dimensions (without feet, with rack ears): 19" W x 3-1/2" H x 14" D.


Actual Tested Specs:



High impedance specs are easier to hit and the dayton isn't far off @ 8ohms but 4ohms is almost half the published spec, nevermind these were at 40Hz and the numbers would be lower and more unstable at 20Hz since distortion is already at [URL=mailto:.33%25@%2040Hz].33% @ 40Hz[/URL].


I would be surprised if the 500W plate amp tested above 300W true RMS output. 

Now, having said all that:
  • I only recommended another amp/pro amp with EQ since you will have to buy one(EQ) anyways and your likely underpowered.
  • Is that TC rated 500W/ coil or 500W total?
  • 86.6db sensitivity, don't leave spl on the table undershooting power requirements.
  • Modeling should help determine your power requirements as excursion will prob dominate your limitations.
  • Double the power = +3b

It's too bad that test will always scar Dayton's rep. It must have been a faulty amp. That amp has been measured by other members on other forums and it was shown to put out rated power. I have one of there 1000 watt plate amps and you can just tell that it's much more powerful than my 500 watt yung amp or oaudio 500 watt amp.

Dan
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post #10 of 233 Old 09-26-2012, 07:42 PM
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Nonsense!!! Everyone knows that if a single sample of a amp can't deliver the rated power in continuous sine waves then it's junk!
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Nonsense!!! Everyone knows that if a single sample of a amp can't deliver the rated power in continuous sine waves then it's junk!
+1
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post #12 of 233 Old 09-26-2012, 08:04 PM
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Quote:
Originally Posted by saabracer23 View Post

I have one of there 1000 watt plate amps and you can just tell that it's much more powerful than my 500 watt yung amp or oaudio 500 watt amp.
I doubt it. Even if the speaker was capable of handling twice the power it would only be at best a 3dB difference, probably less, due to thermal and mechanical power compression. What you're hearing is likely attributable to different gain structures.
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post #13 of 233 Old 09-26-2012, 10:21 PM
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Originally Posted by Stereodude View Post

Nonsense!!! Everyone knows that if a single sample of a amp can't deliver the rated power in continuous sine waves then it's junk!
For one straight hour right? LOL!
I toast my home brewed Oktoberfest to ya man, that was good comedy.

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post #14 of 233 Old 09-27-2012, 06:06 AM - Thread Starter
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Well, worst-case scenario I am still in my 45 day return window for the Dayton. But this is my first product from them and I'm willing to give them a shot. I read both descriptions for the Yung SD500 and the Dayton Audio SPA500 from PE.com...
Quote:
Yung SD500 500W Class D Subwoofer Amp Module No Boost
Yung International's SD Series Class D subwoofer power amplifiers are equipped with the unique ability to operate continuously at full rated output—a performance attribute not shared by most home audio amp designs. The benefits of this remarkable reserve capacity include solid, punchy dynamic range and fewer "nuisance" shutdowns when operated at sustained high levels.

The amplifiers are also extremely compact, lightweight, and cool-running, allowing users to enjoy the advantages of compact system form factors and flexibility of placement. An internal peak limiting circuit prevents amplifier overload, and protection against internal and external faults is also provided. Input power requirements are user configurable to either 115 VAC or 230 VAC line voltage.

Room optimization and system integration are accomplished easily, thanks to the SD Series amps' inclusion of fully variable level, crossover frequency, and phase controls. Signal input is connected via dual RCA-type jacks, including the means to accept the output of an A/V receiver's LFE output, and dual RCA jacks are also provided to facilitate line level loop-through. The amplifier also accepts high (or speaker) level input signals through binding post terminals. When in standby mode, the amp's full active operation is engaged by signal presence of less than 1/2 watt.

Specifications: • Measured power output: 500 watts RMS into 4 ohms @ < 1.0% THD • Signal to noise ratio (at rated power): >90 dB • Input sensitivity (@ low level): 210 mV/50 Hz • Input sensitivity (@ high level): 3.0V/50 Hz • Low pass adjustment: 40 Hz to 200 Hz • Phase adjustment: Continuously variable from 0º (normal) to 180º (reverse) • Power requirements: Switchable, 115/230 VAC, 50/60 Hz • Dimensions: 9-7/8" W x 10-5/8" H x 3" D; Cutout dimensions: 8-7/8" W x 9-3/4" H.
Quote:
Dayton Audio SPA500 500W Subwoofer Plate Amplifier
NEW updated design! One of the most technologically advanced subwoofer amplifiers on the market today! The Dayton Audio SPA500 subwoofer amplifier is based on a state-of-the-art Class-G circuit topology that combines the proven high power, high fidelity characteristics of a Class-AB amplifier with a patented tracking down converter power supply to achieve an operating efficiency up to 86%. You get the efficiency of a Class-D amplifier without compromising audio quality and reliability. The Class-AB output stage provides the clean and low-distortion sound that audiophiles demand, without any of the instability problems that plague other high-efficiency amplifier designs.

This American-designed and engineered amplifier uses patented circuitry that continuously tracks the input signal to modulate or control the voltage available to the output stage. This "tracking" capability delivers the exact amount of power based on demand instead of constantly keeping it in reserve, so the output stage only draws the amount of power that is required at any given time. Less energy is wasted as heat, and more power is available for the subwoofer driver. With its enhanced thermal management, the SPA500 is an upgrade over previous models—making it a nearly bulletproof amplifier choice for today's demanding HT audio and music playback applications.

Specifications: • Rated power output: 273 watts into 8 ohms, 540 watts into 4 ohms with 0.92% THD (based on one-third power duty cycle) • S/N ratio: 98 dB (A-weighted) • Low-pass crossover: 30 - 200 Hz, 24 dB/octave • Input voltage: User switchable 115/230V (Euro cord available) • Dimensions: 11-15/16" W x 11-15/16" H x 5-1/4" D; Cutout dimensions: 10" W x 10" H.

You people speaking out against the SPA500, is Dayton a crap company or something, like the home audio version of Boss or Pyramid?

It's good to know, also that it has a built in subsonic filter @ 18hz....I was wondering about that.

One of the things that sold me on this amp was the parametric EQ with -14.5-+6 db. I think that will help me with room correction, yes?

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post #15 of 233 Old 09-27-2012, 06:21 AM
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Can anyone comment on how the Yung plate amps compare to other plate amps and pro-amps? Debating on going with a Behringer iNuke 1000 (non Dsp) versus a Yung 500 watt plate amp.
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post #16 of 233 Old 09-27-2012, 06:30 AM - Thread Starter
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Quote:
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Regardless, take the leap and build something. Your first project may not be your best, but it's how you learn...

HAve fun,
Frank

Frank, would you mind explaining to me why you would not recommend a large sealed box? From what I know, sealed is tighter and more accurate, also protects the driver from bottoming out (my Kicker Solos are in a sealed box)...but you sacrifice a bit of low end, yes? If I can still get over 100db @ 20hz in a sealed enclosure, I think I would like to try that as my first project...what do you think?

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post #17 of 233 Old 09-27-2012, 06:36 AM - Thread Starter
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Quote:
Originally Posted by imagic View Post

I'm sorry to not answer your question the way you wanted but... If you buy an iNuke, you gotta get the DSP version,

Yeah, I don't have any home audio experience with DSPs, but back in '06 Kicker was still selling the SX amp line. They had DSP and a cool networking feature that allowed you to run a CAT 5 cable from amp to amp and then to the front of your car to a digital display that fit in your DIN...you could hook up to 15 amps in a signal chain and have then all controlled by the SXRC remote...

it had parametric eq, phase, mute, gain, kompressor, voltage matching...it all still works flawlessly too...I love having that level of control and I was very disappointed when they phased that line out to go with the DX...which is all analog dials...

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post #18 of 233 Old 09-27-2012, 07:50 AM - Thread Starter
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Hey there, how are the Solos? Are they in your car? I wanted to do a sealed home theater sub with an 18" Solo-X but I'm in a holding pattern with the WAF issue.

They are in my car. Two square L7 12's in a sealed box that has them facing each other about 11" apart and then ported through my armrest. Best bass I've ever heard. I used to go to empty parking lots and just plug my ears up and sit back and get a sick bass back massage for about an hour blasting Bass Mechanik CDs.

My wife used to get so mad at me because I would set off car alarms in the neighborhood. My cab vibrates so much it made your arm hairs tickle and your eyes water. I'd say they have withstood the test of time, also, 6 years running and in South Florida heat and humidity and being worked out very strenuously even to this day...you should hear dubstep on my system. biggrin.gif

They have huge magnets, are very well made, at least they were in '06 who knows how much cheap chinese crap is in them now though...

The Solo X is absolutely sick...I wanted to get one 18" with the Warhorse but I ran out of money, lol...

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post #19 of 233 Old 09-27-2012, 08:27 AM
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Quote:
Originally Posted by saabracer23 View Post

It's too bad that test will always scar Dayton's rep. It must have been a faulty amp. That amp has been measured by other members on other forums and it was shown to put out rated power. I have one of there 1000 watt plate amps and you can just tell that it's much more powerful than my 500 watt yung amp or oaudio 500 watt amp.

Dan

 

Hi Dan,

 

Can you link me to those tests?  I like the amp just don't believe the specs.

 

Quote:
Originally Posted by Stereodude View Post

Nonsense!!! Everyone knows that if a single sample of a amp can't deliver the rated power in continuous sine waves then it's junk!

 

Well it doesn't help.

 

Quote:
Originally Posted by mfrey0118 View Post

Well, worst-case scenario I am still in my 45 day return window for the Dayton. But this is my first product from them and I'm willing to give them a shot. I read both descriptions for the Yung SD500 and the Dayton Audio SPA500 from PE.com...
You people speaking out against the SPA500, is Dayton a crap company or something, like the home audio version of Boss or Pyramid?

It's good to know, also that it has a built in subsonic filter @ 18hz....I was wondering about that.

One of the things that sold me on this amp was the parametric EQ with -14.5-+6 db. I think that will help me with room correction, yes?

 

The dayton amp is a fine plate amp.  It appears very well built.  You should have no problem besting those commercial subs you mentioned with your current hardware.  A properly designed ported sub should perform well with your current setup.  As prev mentioned one twelve is gonna drown in your room, it just has too many cubic feet to compress.

 

One band of EQ will help, you might be able to squash one constructive mode, but thats about it.

 

I do believe you'll be underpowering the driver:

 

The amp ships with a 5A fuse.  Assuming a max current draw of 5A.  120V*5A=600W.  Efficiency is rated at 75%.  .75*600=450WRMS This is a generous assumption assuming the amp would pull current at the max rating of the fuse.  Acutally its prob pulling close to 3-4 Amps since fuses are over sized(typically by 33%) for acutal current draw dropping your max calculated power to 360WRMS.

 

Back of the amp claims 500W draw.  500*.75= 375WRMS  The amp can't make more power than it draws, its not a generator.

 

The devil is in the details.  They rate their amps 1/3 peak power, not RMS.  Measuring "Peak Power" is highly dependent on the methodology used to test.  Numbers are only comparable to others tested exactly the same. 

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post #20 of 233 Old 09-27-2012, 08:33 AM
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If you decide to return the Dayton, I recommend the Behringer NU3000dsp.  620W RMS per channel into 4ohms.  Then you can build another sub later and power off the other channel.  Trust me you will want another.  Sub building is like a sickness, you will want more.

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post #21 of 233 Old 09-27-2012, 08:55 AM
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Quote:
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Then you can build another sub later and power off the other channel.  Trust me you will want another.  Sub building is like a sickness, you will want more.

Ain't that the truth!

That is the very reason I went with the iNuke3000DSP.
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post #22 of 233 Old 09-27-2012, 12:17 PM
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Originally Posted by mfrey0118 View Post

Frank, would you mind explaining to me why you would not recommend a large sealed box? From what I know, sealed is tighter and more accurate, also protects the driver from bottoming out (my Kicker Solos are in a sealed box)...but you sacrifice a bit of low end, yes? If I can still get over 100db @ 20hz in a sealed enclosure, I think I would like to try that as my first project...what do you think?

Sealed boxes have a natural drop in output at low frequencies. They do protect the driver, but it's a tradeoff between box size and power handling - you can still bottom a driver in an overly large sealed box unless the driver's designed for that application. Due to the roll-off, sealed works best with some active boost at the low end, and they are best used in a room that's small enough for room gain to augment the boost at very low frequencies. Your room is so large (35' with large openings to other rooms) that room gain isn't much help, and boost just hurts your headroom.

That's where the LLT comes in. Being low tuned, port output is infrasonic; you're hearing only driver output in the range where "tighter and more accurate" actually matter. In one case, F3 is 20Hz with an F10 in the low teens for LLT, compared with F10 of 20Hz for sealed. The same driver gives ~7dB greater output at 20Hz for the same applied power... and you need it with that size room. Hoffman's Iron Law cannot be broken - size, loudness, extension: pick 2.

It's all about matching the device to the application...

Have fun,
Frank
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post #23 of 233 Old 09-27-2012, 02:06 PM
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Originally Posted by NicksHitachi View Post

The amp ships with a 5A fuse.  Assuming a max current draw of 5A.  120V*5A=600W.  Efficiency is rated at 75%.  .75*600=450WRMS This is a generous assumption assuming the amp would pull current at the max rating of the fuse.  Acutally its prob pulling close to 3-4 Amps since fuses are over sized(typically by 33%) for acutal current draw dropping your max calculated power to 360WRMS.

Back of the amp claims 500W draw.  500*.75= 375WRMS  The amp can't make more power than it draws, its not a generator.

The devil is in the details.  They rate their amps 1/3 peak power, not RMS.  Measuring "Peak Power" is highly dependent on the methodology used to test.  Numbers are only comparable to others tested exactly the same. 
The devil is in the details and unfortunately, you've gotten them all wrong.

1) Do you know what the 5A rating on a fuse means? Wait, I can answer that. You post shows you don't... A 5A rating means the fuse can sustain either 130% (North American) or 150% (IEC) of it's current rating for 1 hour (continuous) before it blows. For short peaks and transients you can pull 200% of the rating and it still won't blow.

2) The manufacturer puts a typical power draw on the device. They are not obligated to put the absolute worst case peak power draw number. That UL rating doesn't mean the amp can't put out 500W.
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post #24 of 233 Old 09-27-2012, 04:21 PM
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Quote:
Originally Posted by Stereodude View Post

1) Do you know what the 5A rating on a fuse means? Wait, I can answer that. You post shows you don't... A 5A rating means the fuse can sustain either 130% (North American) or 150% (IEC) of it's current rating for 1 hour (continuous) before it blows. For short peaks and transients you can pull 200% of the rating and it still won't blow.

2) The manufacturer puts a typical power draw on the device. They are not obligated to put the absolute worst case peak power draw number. That UL rating doesn't mean the amp can't put out 500W.

 

1)  I think YOU may be confusing a fuse with a breaker which meets your stated criteria in some cases.  Fuses are rated fast blow, slow blow, etc and dont meet any "continuous" requirement.  Fast blow "common fuse" blow if they pass more than rated current which in this case is 5A.  Slow blow fuses are much more tolerant too transient spikes etc.

 

2)  I never said the 500w was a max rating, but you are correct in that its an average of the power draw.  thats a good observation, however depending on the amp architecture some amps draw the same power reguardless of how hard their driven.  IDK about the architecture of this one, it states special circiutry but its prob just a tweaked A/B.

 

Nitpicking someone else's post is easy, why don't you come up with something positive and constructive to add for the OP.

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post #25 of 233 Old 09-27-2012, 06:11 PM
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Quote:
Originally Posted by NicksHitachi View Post

1)  I think YOU may be confusing a fuse with a breaker which meets your stated criteria in some cases.  Fuses are rated fast blow, slow blow, etc and dont meet any "continuous" requirement.  Fast blow "common fuse" blow if they pass more than rated current which in this case is 5A.  Slow blow fuses are much more tolerant too transient spikes etc.
I'm not confused. The information I provided is 100% accurate. Why don't you educate yourself instead of trying to claim the person debunking your smear attack is wrong.
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Nitpicking someone else's post is easy, why don't you come up with something positive and constructive to add for the OP.
First, correcting blatant misstatements is not "nitpicking". Second, I'm doing something constructive for the OP. I'm demonstrating your attack on the Dayton amp to be baseless and without merit.
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post #26 of 233 Old 09-27-2012, 06:39 PM
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Originally Posted by imagic View Post

For bass, the iNuke just works... perfectly. I went with the 6000DSP, no regrets- two iNuke 3000's bridged, in one box for $100 extra... and even so I've clipped it thanks to the LFE track on XMFC. The 4-channel 6000 is coming soon, I gotta have it: http://www.behringer.com/EN/Products/NU4-6000.aspx
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Ain't that the truth!
That is the very reason I went with the iNuke3000DSP.

I helped a buddy integrate a berry dsp on two f20s they are the easiest pro amp/eq ive ever used.
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post #27 of 233 Old 09-28-2012, 06:22 AM - Thread Starter
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Yeah, I don't want to get into "I would buy this amp..." or "You should get this driver". It's counterproductive to the intent of my thread, as much as it may contain truth...

What I would like is assistance in working with the equipment I mentioned.

60" 1080p 3D Plasma Panel
3D 1080p Blu-Ray player
4K 7.2 Channel AVR

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post #28 of 233 Old 09-28-2012, 08:13 AM
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Quote:
Originally Posted by mfrey0118 View Post

Yeah, I don't want to get into "I would buy this amp..." or "You should get this driver". It's counterproductive to the intent of my thread, as much as it may contain truth...
What I would like is assistance in working with the equipment I mentioned.
Did you already buy the driver? If so, a single sealed 12 in that size room will have underwhelming performance and you'd be better off building a larger ported box tuned to around 20hz. It would at least give you more performance within an octave of your tuning frequency. 100db@20hz might sound like a lot of bass, but it's not. At your listening position, you might be at 90db...

If you wanted to go sealed in that size room, a good starting point would be twin 15's and >600w total power. But you'd likely want to double that within the year if you're like most folks around here.

YID DIY
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post #29 of 233 Old 09-28-2012, 06:18 PM - Thread Starter
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Originally Posted by imagic View Post

Well I've got good news for you. I just modeled the 12" epic in a 60 liter sealed box (2.1 cubic feet) and it hits 100db with 350 watts. That satisfies the specs you wanted to meet, and that size/type box is easy to build or to buy prefab. If you shop Parts Express, you could buy a cabinet with a cutout for your amp. The LLT will buy you more sound, 3-6 decibels more in the lowest octave... but would need to be at least 3X larger. Personally I like sealed subs but I definitely get the argument for LLT as well... but with a 2 cubic foot box you could be done quick and easy and get what you asked for with the parts you've got.


Whoa, thanks for taking the time out to do that! That's good to know, a sealed box would be a great starter project for someone like me with zero experience...

60" 1080p 3D Plasma Panel
3D 1080p Blu-Ray player
4K 7.2 Channel AVR

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post #30 of 233 Old 09-28-2012, 06:31 PM
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here is the dilemma. 2.1 sealed in yellow. 5 cubic feet net ported to 20hz (that is about what the svs pb13u cab is).

350 watts into each cab. in a large room, you won't get a ton of gain, so if you want strong 20hz... :-)


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