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Recommended amplification strategy for Parts Express Dayton UM18-22 kit?

cavedriver

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Looking at buying the fairly popular 6 cu ft sealed UM18-22 kit from PE and I was trying to decide how to amplify it. The obvious choice is a Crown XLS 1502 (I think), but what about the linearity on this driver in a sealed box like this? There was a website called data-bass.com that seems to have shut down that had measured it. Reposts from it suggest it's fairly flat with a gentle roll-off on the low end but without the original article I am not sure how they tested it except that people said they used a 6 cu ft sealed box. Is this correct?

The alternative is to set aside one channel from my minidsp and really try to "flatten" it but I would prefer to keep the minidsp free to use in other rooms. Since the minidsp is worth about $500, plus $600 for the build and another $600 for the amp, using the minidsp creates the problem that I could just buy a Monolith 13" at $1700, or even less if I can get it on sale. Although I have the output curve for the Data-bass test, I don't know what the CEA limits are so I also don't know how the UM18-22 could compare to the Monolith in max output. Finally, maybe there is a DIY alternative to the Crown that people are using? I've found the Wondom DSP and amp products but haven't found anyone document how they used them for a sub.
 

fpitas

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fpitas

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I'd probably get one of the latest class D offerings reviewed here to drive it.
 

Ron Texas

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XLS amps claim to be able to drive 2 ohm loads. I'm using a 1502 to drive LS50's from 100 Hz up. In terms of power it's complete overkill.
 

fpitas

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cavedriver

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Plate amps in general are kind of notorious for failing quickly. But they are cheap.
yes, also the UM18-22 can take gobs of power, like 1000W, especially with DSP, so the largest of the Dayton DSP plate amps is still too weak. It also eats into the cabinet volume, which is already just at the recommended minimum for good extension in a sealed design for this woofer.
 

Count Arthur

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It also eats into the cabinet volume
You can always mount an external box for the plate amp, they even make one, but if you feel you need more power, you'll have to look elsewhere. I have no experience with regard to reliability; although I don't see why a plate amp should inherently be less reliable than one in a box, all things being equal.

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617

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I recommend the dayton dsp amps. You don't need to push the driver to full power, the output of these drivers is immense.

Remember watts and loudness do not have a linear relationship. 500w is only 3db less than 1000w, and 100w is only 6db less.

The dayton dsp 500 amp would be a very good option. I have the smaller one for my office and it was very easy to set up. You can use a pc interface via USB or just use the interface on the amp itself.
 

fpitas

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I don't see why a plate amp should inherently be less reliable than one in a box, all things being equal.
I agree. But it seems they are usually made to be kind of disposable.
 

middlemarch

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I use one channel of an XLS 2502 to drive mine and it doesn't even breathe hard for all the bass I care to handle. Then you have another channel for your second sub (can't have just one).
 

DVDdoug

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I ALWAYS recommend speaker design software to model the design & predict performance and to optimize box volume and port dimensions in a ported design. (The software will help you decide which is better.)

Everything is a trade-off! ;)

Reposts from it suggest it's fairly flat with a gentle roll-off on the low
Without doing any research on this particular driver & box...

In general, sealed designs then to roll-off more gently than ported designs. But you usually get more output from a ported design down to where it starts rolling-off, and it can start rolling-off at a lower frequency. So for example, the ported box might give you more output at 40Hz, but it rolls-off more quickly and the roll-off curves cross so the sealed box may be putting-out more at 20Hz. You can also tune the ported box with a little 1 or 2dB bump (or whatever) and extend-down the -3dB point a bit more.

Given a "small" box, a smaller driver will usually have a lower cut-off frequency (but less output capability).

Because of the more-gentle roll-off, it's easier to EQ & flatten a sealed box. If you want to go as low as possible, a sealed box with EQ, and a high-power amplifier and high-power driver is often the best way to go. You can also get-away with a smaller box if you can "overpower" it with EQ and wattage. In a home environment, you don't need a lot of efficiency. And since the roll-off is (usually) gentle & smooth you don't need fancy DSP EQ (ignoring room acoustics).

Pro subs used live and in dance clubs are usually highly efficiency ported designs that go-down to around 40Hz. It's the best compromise to fill a large space with bass you can feel. (Just for reference, the lowest-note on a standard bass guitar is about 42Hz.)

If you add a lot of low-end boost to a ported box, the driver tends to move freely-uncontrollably, with less sound-output at the lowest frequencies (because of that steeper roll-off) and the EQ just doesn't work as-well. You end-up wasting a lot of power and you are more likely to burn-out the speaker.

...My homemade subs are 15-inch drivers in large ported cabinets I think they tuned to around 30Hz, per the design software. I didn't measure them and I don't exactly remember, but they can "rattle the walls" and they put-out bass you can feel in your body.
 

Palmspar

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I use a Hypex FA501 plate amp in my DIY subwoofer, in HFD software its easy to make filters for the dsp.
The sub has a even flat response as a SB2000 and its +-3db point is tuned slightly deeper.
 
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Get a used crown XLS 2000 series. It's what I use with mine and it will take full advantage of the driver. Each voice coil has its own channel at 2ohms. My crown 1500 will clip/shut off when driven too hard with the driver.
 

Axelpowa

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Has anyone thought about using the SVS 13 ULTRA Amplifier Kit? For 600€

Its rated 1200w rms and 4000peak with a nice dsp and bluetooth control with mobile app.

Regards!
 

anotherhobby

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I use a pair of Crown XLS1500's for my 4 Dayton 8" Ultimax subs. I ended up with a 4 ohm config, but in my testing the amp clipped at the exact same levels with a 2 ohm load. I ran them at 2 ohms for about a month and they handled everything fine, with no difference other than wiring. They also clip safely in that the amp just "clicks" into protection mode for a second or two and then returns to operation if you over drive it. As a bonus, the onboard fans are surprisingly quiet compared to other pro amp options with this power level.
 
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cavedriver

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I use a pair of Crown XLS1500's for my 4 Dayton 8" Ultimax subs. I ended up with a 4 ohm config, but in my testing the amp clipped at the exact same levels with a 2 ohm load. I ran them at 2 ohms for about a month and they handled everything fine, with no difference other than wiring. They also clip safely in that the amp just "clicks" into protection mode for a second or two and then returns to operation if you over drive it. As a bonus, the onboard fans are surprisingly quiet compared to other pro amp options with this power level.
That would make sense if it's the power supply limiting the output. Some of the class D amps (I forget which of Amir's reviews) showed that 2 ohm output was really limited by the power supply and as a result was not markedly greater than the 4 ohm output.
 
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cavedriver

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Has anyone thought about using the SVS 13 ULTRA Amplifier Kit? For 600€

Its rated 1200w rms and 4000peak with a nice dsp and bluetooth control with mobile app.

Regards!
Since it's designed for a specific SVS sub it doesn't look like they will be too forthcoming on some of the specs and perhaps limit one's access to the full DSP capabilities. In other words, there may be no way to use it on anything other than the intended SVS sub unless you hack the DSP settings and remove whatever custom layers they have in there. Nonetheless, the capabilities and power for the price appears to be quite good.
 

Palmspar

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Has anyone thought about using the SVS 13 ULTRA Amplifier Kit? For 600€

Its rated 1200w rms and 4000peak with a nice dsp and bluetooth control with mobile app.

Regards!
The Hypex FA502 has in bridge mode 1000w@4ohm and HFD software where you can make custom filters for any driver and size box.
But in a normal room and listening levels 500w@4ohm is already more then you wil ever use.
Dual opposed sub design is also a great way to have more spl.
For a dual opposed sub with 500w total power compared to the same single driver it needs 1000w to have the same max output but it has way more distortion.
If a 12 inch dual opposed sub has 12mm max cone travel the single sub must do 24mm for the same output level.
A good 12 inch subwoofer driver has no distortion at 12mm cone travel, but for 24mm i am not sure there are any.
 
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