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(8) Sealed Incriminator Audio Judge 21" build


lukeamdman

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Say Luke, how often do you play those things loud enough to even see the drivers move?

 

Every few months I put them in full range mode and have some fun.

 

When I first got the drivers I ran them free air just to see how quiet the suspension was.  I ran a 10hz sine wave at about 1-1.25" p-p excursion and they were almost completely inaudible.  It was eerie.   

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So Luke...Have you had time to form an opinion on whether the content below 12Hz adds much in your room?

 

I just got the second SP2-12K today, so I'll be testing this more thoroughly soon.

 

I did do some blind testing with Mike on some movie clips that dip to 10hz and a little lower, and he was 100% accurate when asked if a LT was applied or not.  However, even though the could tell the difference, we both concluded that for a ~10db increase at 10hz and below it was much more subtle than you'd imagine.  For 10db you expect something much more noticeable but that wasn't the case.

 

My next test will be comparing a frequency response that's flat to 10hz but drop quickly below that with a frequency response that's flat to 3/4hz. 

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Cool. I'd like to hear your thoughts on what happens when you filter out <10-12Hz versus having it there. I'm looking for more opinions from people on basement slabs with enough displacement and extension for it to mean something.

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Cool. I'd like to hear your thoughts on what happens when you filter out <10-12Hz versus having it there. I'm looking for more opinions from people on basement slabs with enough displacement and extension for it to mean something.

 

It seemed pretty apparent to me at the g2g after we got the dash-v prototype in the chain. But we also took a little peak out as well when that went down. 

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Cool. I'd like to hear your thoughts on what happens when you filter out <10-12Hz versus having it there. I'm looking for more opinions from people on basement slabs with enough displacement and extension for it to mean something.

 

I don't have a way of filtering out that portion of the bandwidth but I can say there is some effect (pre-riser) with <10-12hz content. I'd describe it as subtle. Bosso would say that stuff is more noticeable with transient effects rather than continuous and I'd have to agree.

 

Not sure doubling up on the subwoofer system would really increase the perception of these effects, imho. I think you gotta concentrate on tactile transmission effects in this bandwidth. Suspended floors, risers, tactile transducers, etc. That I think is the best way to perceive these effects in a useful way. The brute force approach some of do works but is an inefficient way to produce these effects. Too often guys like us run at war volume and shake the living shit out of the house but at the seat the effect is "meh". Sounds like the house is going to crash down though.

 

Just my opinion after living with dual 18 LLT's for years and a couple of years with over a dozen sealed 18's in a small room and experiencing other peoples rooms with similar setups.

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It seemed pretty apparent to me at the g2g after we got the dash-v prototype in the chain. But we also took a little peak out as well when that went down. 

 

Before adding the Dash V was the extreme low end ever filtered out like it would be with a high pass on a vented or horn system though? I don't know what type of response you had before and after. Plus we were running how hot on the bass again? +37dB?

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Before adding the Dash V was the extreme low end ever filtered out like it would be with a high pass on a vented or horn system though? I don't know what type of response you had before and after. Plus we were running how hot on the bass again? +37dB?

 

Essentially yes, the bass dropped like a rock right at 10hz. +37dB sounds about right.

 

Wow? That much?

 

I thought it was set to 'just right'. :D

 

Me too. Everything less just sounds so.......thin.

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For me (on a slab right now), I have gone from:

 

1. 40Hz at -20dBRef

2. 30Hz at -15dBRef

3. 16Hz at -10dBRef

4. 6Hz at -7dBRef, can push to -4dBRef but then mains limited

 

Biggest change was 30 to 16, but not apples/apples as spl capability continued to rise. I can tell when content under 10Hz is present, but like Scott said, most easily experienced on transients. There is a significant difference between a Danley firework recording with and without a highpass, even on the slab.

 

The room will finally dictate the difference you sense for <10Hz.

 

Lately, I have been trying to get more upper bass transient response abnormalities fixed.

 

With enough drivers/power, anyone can do <10-15Hz provided the signal chain supports it.

 

But to get the clean slam of a well-tuned cinema is something else entirely.

 

JSS

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Interesting discussion here.

 

If I'm reading right, many here are calling "10 Hz" a point of diminishing returns.  It's ironic for me in my current situation (see the plot of my approximate room gain profile).  Getting extension to 20 Hz with a sealed system is easy, but any extension below there requires a huge increase in displacement.  The required increase is about 8X from 20 to 10 Hz.  But once I get performance to 10 Hz, I get the 5-10 Hz octave pretty much for free.  Actually, it's better than it looks because there's a fair amount of signal chain roll-off in the measurements.

 

What I have no idea about is how much house shaking I'll get from under 20 Hz content, particularly the stuff below 15 Hz if I try to run things flat to 10 Hz.

 

For me (on a slab right now), I have gone from:

1. 40Hz at -20dBRef
2. 30Hz at -15dBRef
3. 16Hz at -10dBRef
4. 6Hz at -7dBRef, can push to -4dBRef but then mains limited

 

Out of curiosity, do you base these performance figures on ability to handle a WCS event?  Or do you assume a WCS won't actually happen in the ULF?  I guess the closest things to a ULF WCS for actual content would be the EOT intro?  I don't think I'll be able to reproduce that 10 Hz tone in EOT at "0" with any multi-sealed sub system I'm contemplating for this room.  Could I do it with 4 X HS-24s?  Maybe, but barely if at all.  And 4 X HS-24 is getting ludicrous already.

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No, this is for program material, I did not have WCS testing capability until system #3.  My current WCS limit is -11dBRef, excursion limited with a 3Hz WCS burst.

 

EoT is only two channels at full-tilt with coherent sound.  All 8 channels coherently adds significantly more demand from the system.  At some point, a test disc will be created.

 

JSS 

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No, this is for program material, I did not have WCS testing capability until system #3.  My current WCS limit is -11dBRef, excursion limited with a 3Hz WCS burst.

 

EoT is only two channels at full-tilt with coherent sound.  All 8 channels coherently adds significantly more demand from the system.  At some point, a test disc will be created.

 

JSS 

 

Are your sealed cabs low qtc? What's the airspace each driver sees?

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Speaker/Box Qtc 0.8 per sims and calcs.  That is not with a dead flat house/FR curve though.  My 'flat' curve still rises some from 20kHz to 10Hz.

 

I didn't try higher freqs as more velocity = more damage.   My tonebursts are enveloped so that the outward stroke/positive swing gets max voltage, so my limit may be a little less than -11dBRef at 3Hz.

 

JSS

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Had a mini-GTG on Friday.  Originally it was just desertdome/mojave visiting, but it ended up being 6 guys!  We brutalized the house from 7pm to almost 12:30am!

 

On Saturday morning, we bypassed all EQ/XO to my mains and Mike hooked up a Motu UltraLite AVB and his spendy microphone.  In about 20 minutes he had everything completely dialed in and I dare say it sounded even better!  At first it was a tad bright but one quick update to the target curve and bingo.  Crazy good. 

 

The Motu combined with Audiolense is incredibly capable.  Gated measurements and it sweeps each individual channel.  With a few software updates I could easily see that in my system in the future. 

 

Mike also brought Ragnarok and yeah, tons of 10-30hz bass.  I just ordered it. 

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Had a mini-GTG on Friday.  Originally it was just desertdome/mojave visiting, but it ended up being 6 guys!  We brutalized the house from 7pm to almost 12:30am!

 

On Saturday morning, we bypassed all EQ/XO to my mains and Mike hooked up a Motu UltraLite AVB and his spendy microphone.  In about 20 minutes he had everything completely dialed in and I dare say it sounded even better!  At first it was a tad bright but one quick update to the target curve and bingo.  Crazy good. 

 

The Motu combined with Audiolense is incredibly capable.  Gated measurements and it sweeps each individual channel.  With a few software updates I could easily see that in my system in the future. 

 

Mike also brought Ragnarok and yeah, tons of 10-30hz bass.  I just ordered it.

 

Told you Ragnarok was great bass. ;)

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Very interesting experiment.  The 6Hz should be noticeable with the room closed (pressure sensation), but since you are on a slab, maybe/maybe not.

 

Do you notice?

 

BTW - that is a nice FR.  No cancellations.

 

JSS

 

I can only tell if I stand in the room above the HT. 

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What's a passive radiator riser?  Is that like building the riser as a sealed box subwoofer with very large surfaces?  Then the large surfaces won't be very rigid and will act kind of like passive radiators.  Right?

 

Or maybe you are just making a joke.  :)

 

I'm sorry to hear that < 10 Hz doesn't make a noticeable difference on your slab.  It definitely begs the question of whether there's a point to sub extension below 10 Hz if you don't actually hear or feel it without a suspended floor of some kind, even if you do have such a floor or riser.  Because then, you could always install tactile transducers to get the same experience while subjecting your subs (and house) to less stress.

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