DIY Sub Questions

[wvu80]

11 hours ago, ACV92 said:

One other note, I feel a little dirty being on a Klipsch forum and I haven't mentioned Klipsch in my posts.  This sub setup will be with my KG 5.5's.  I know, not the most noteworthy of Klipsch's past and present offerings., but I've been happy with them.

I try to always be aware that Klipsch is the host and I am a visitor here, so I try to be respectful of Klipsch products and not undermine sales or defame their products. 

 

I think of DIY the same way I think of buying and selling used Klipsch products, they are not a direct competitor to Klipsch, Inc.  The DIY sub is usually a no-name, has no warranty and does not have the finish a Klipsch sub would have.

 

In that light ACV92 I think your conscience should be clear and your motives for discussing a DIY build, honorable. 

[ACV92]

DizRotus - Thanks for the link.  I've started with room acoustics and will move around from there.  This is what I was looking for.  So much to learn.

 

wvu80 - You've eased my conscience.  I've always enjoyed the sound reproduction and efficiency of the Klipsch products that I've heard.  I'm trying to upgrade as I can and Klipsch will definitely be in the mix.  After the sub project I want to go audition some RF-7's.  Then start saving some more pennies.  But first, I should move to a preamp/amp combo setup to run them........

[Paducah Home Theater]

On 2/14/2017 at 3:02 PM, jason str said:

 

I disagree, they are made specifically for driving subwoofers is all.

 

Show me a cheap-ish subwoofer amp like the Daytons that you like and I'll show you an amp that can't handle subsonic frequencies very well.   There's a reason why nicer amps like SpeakerPower exists and it's not because all other amps can handle that stuff just fine.  

 

 

On 2/14/2017 at 3:02 PM, jason str said:

Nothing but spewing distortion at higher SPL subsonic frequencies anyways, can't figure out why anybody would want this incorporated in their music playback myself but whatever floats your boat. Maybe if you had the proper tools for this with home theater (IE lots of large cabinets to handle the load) i can see the need but otherwise i say you are just pissin into the wind.

 

I don't even know of any normal music that has those frequencies.  You'd have to purposely be playing with "bass I love you" at 7 hz or the lowest possible pipe organ frequency ever recorded at 8 hz.  Otherwise it's strictly for home theater.  Subsonic filters are handy for high tuned ported boxes where you're going to destroy a driver if you play it hard below the tuning frequency where it is unloaded, maybe pro audio where you're plugging stuff in and out and a low pop could damage some stuff, but personally I think it's a little unnecessary to say the least for a sealed box inside a home.  Not sure why anybody would consider it to be a high priority for sure.  You'd be hard pressed to even find something with that stuff in the recording.  

[jason str]

1 hour ago, MetropolisLakeOutfitters said:

 

Show me a cheap-ish subwoofer amp like the Daytons that you like and I'll show you an amp that can't handle subsonic frequencies very well.   There's a reason why nicer amps like SpeakerPower exists and it's not because all other amps can handle that stuff just fine.  

 

The Dayton 250 watt amp works perfect with most of the larger horn loaded home audio subwoofers i build, for most direct radiating models i recommend Crown units but in the end its up to the customer to decide what they want. My in ceiling subs i build for the local AV business are run with Lab Gruppen witch i think is overkill but again not up to me.

 

I don't even know of any normal music that has those frequencies.  You'd have to purposely be playing with "bass I love you" at 7 hz or the lowest possible pipe organ frequency ever recorded at 8 hz.  Otherwise it's strictly for home theater.  Subsonic filters are handy for high tuned ported boxes where you're going to destroy a driver if you play it hard below the tuning frequency where it is unloaded, maybe pro audio where you're plugging stuff in and out and a low pop could damage some stuff, but personally I think it's a little unnecessary to say the least for a sealed box inside a home.  Not sure why anybody would consider it to be a high priority for sure.  You'd be hard pressed to even find something with that stuff in the recording.

 

You are welcome to do whatever you like with your personal cabinets, i have to warranty mine.

 

 

[derrickdj1]

Most modern avr will use a hpf 2n order(12 db, slope) during autocalibration for the speakers.  Depending on the level of autocalibration, filters for the subwoofer may be set.  There are many schemes of bass management all varying in their resolution.  The take home message is know your  system and it's limits.  Also, the audio chain starts to get weak in the under 12 Hz to 13 Hz range.  This drop off in the audio chain could be in the BPD, amp, avr or any other connected gear.  

 

For vented subwoofers, a good rule for setting the hpf is no lower than 0.8 of box tuning for those pushing the envelope.  For a bit more protection, set the filter to the box tuning.  How can you get by with the 0.8 of box tuning, filters are not brick walls and start to cuff frequencies before the target frequency.

[Paducah Home Theater]

12 hours ago, jason str said:

for most direct radiating models i recommend Crown units

 

Only mentioning this since you were responding to the subsonic comments, but a Crown XLS is actually horrible when it comes to subsonics and cannot handle them at all.  There's an admitted 6 db rolloff, and even a secondary limiter on the power supply, get it up past two lights at 10 hz for even a split second and _click_.  I destroyed one playing a sine wave at 18 hz.  Above 20 hz I like them but Crown anything other than the old school Crown XLS 5000 and whatnot just does't do well with subsonics at all.  

[jason str]

1 hour ago, MetropolisLakeOutfitters said:

 

Only mentioning this since you were responding to the subsonic comments, but a Crown XLS is actually horrible when it comes to subsonics and cannot handle them at all.  There's an admitted 6 db rolloff, and even a secondary limiter on the power supply, get it up past two lights at 10 hz for even a split second and _click_.  I destroyed one playing a sine wave at 18 hz.  Above 20 hz I like them but Crown anything other than the old school Crown XLS 5000 and whatnot just does't do well with subsonics at all.  

 

There is no rolloff, its flat to 10 Hz.  You were probably trying to drive too low impedance.and triggered the protection circuit.

 

I have had no complaints from customers.

[Paducah Home Theater]

22 minutes ago, jason str said:

 

There is no rolloff, its flat to 10 Hz.  You were probably trying to drive too low impedance.and triggered the protection circuit.

 

Everybody at Crown will readily tell you there's a 6 db per octave rolloff, which has been the case with many of their amps for a long time, and I was running 4 ohm stereo which is easy peasy to drive.  

[jason str]

25 minutes ago, MetropolisLakeOutfitters said:

 

Everybody at Crown will readily tell you there's a 6 db per octave rolloff, which has been the case with many of their amps for a long time, and I was running 4 ohm stereo which is easy peasy to drive.  

 

 

 

See post #124 and work your way down. >link<

 

When you are through with that read through >this<

 

 

[Paducah Home Theater]

1 hour ago, jason str said:

 

 

 

See post #124 and work your way down. >link<

 

When you are through with that read through >this<

 

 

 

So at 10 hz it's 10 db down from where it was at 20 hz, and because it's only 1 db different than a Crest amp, you deem it to be flat?  Makes perfect sense.  All cheap class D amps look like that, Crest/Peavey, Crown, iNukes, they all drop off below 20 hz.  Here's a graph showing the same thing and everybody's acting like it's flat, I don't get it.  

Also some of these measurements are very short bursts.  SpeakerPower's ratings are based on 6 seconds straight and it only drops like 3 db after that.  Apples and oranges yet according to this they're in the same league.  They're not.  

[jason str]

22 minutes ago, MetropolisLakeOutfitters said:

 

So at 10 hz it's 10 db down from where it was at 20 hz, and because it's only 1 db different than a Crest amp, you deem it to be flat?  Makes perfect sense.  

 

Look at the voltage output of all the different amplifiers at different frequencies.

[derrickdj1]

Why even worry about anything that low.  Tune your sub higher and get a lot more out above.  It will equal what you are getting from extension down that low.  Chasing output at 10 hz or below is not worth it  when you can add 10  db at 15 Hz-  30 Hz.  I've been chasing this for a while and the amount of amps/power and wooferage can be squashed with just a couple of Crowson for less cost.  To get TR this low is indirect coupling.  TT's will give direct coupling and need to be no where as powerful for the same result.  Set your goals and pick the right gear to get there.

[ACV92]

After reading everyone's posts I've decided I'm going to get the 15" Umax.  I realize the HO is somewhat more musical, but I'm coming from a Klipsch SW-10 single sub in this setup.  I don't think I'm going to be disappointed.  Plus, if this setup grows and I start using it for movies as well I would be covered.  Is there any advantage to putting feet on the enclosure?  It's going on carpet so I'm not worried about floor/enclosure vibrations.

 

Now, I'm down to two amps.  The Behringer NU3000DSP and the Crown XLS 1502 Drivecore. I've read the subsonic output debate and well, I don't feel that will be an issue for me.  Consider the aforementioned sub.

 

So, with the iNUKE are the fans really that loud?  It will be in an entertainment stand that is somewhat enclosed.  The front is open but it's enclosed on all other sides except for a cutout on the rear.  Do you feel that the fan will be that invasive considering it will be about 10' from my face.  The input/output connections are easy enough to work around.

 

The Crown has more input/output options and I figure will have a somewhat similar actual output as the iNUKE.  If anyone has any actual output readings for either at 4 ohm mono/bridged please share them.  The input sensitivity option with the Crown will prove useful.  I don't believe the iNUKE has this feature.  Lastly, are the DSP's similar in capability?  For a relative beginner, is one DSP easier to use then the other?  Is the Crown worth $120 more?

 

Now down to the receiver I'll be currently using.  I've decided to leave the Marantz SR-8400 in our rec room as it is all setup for movies/music.  So, that leaves me with, I'm embarrassed to say, a Yamaha RX-V590.  Please, I can hear you laughing from here.  Here's my question, the LPF on this unit is set at 200hz with a 6db slope.  There is no output level control for the sub out, it is what it is.  I will upgrade as I can, but what problems do you see with the what I'm trying to do?  Am I wasting my time until another upgrade?

 

I apologize for the length of my posts, brevity is not one of my strengths.  Sorry if redundancy creeps in here to.  I'm trying to eliminate buyers remorse before I hit the place order button.  

[ACV92]

One other thing, glue for the enclosure.  Back in the day I, and quite a few car audio installers, used Elmer's Wood Glue.  Is Gorilla Glue, or others, better?

[minermark]

4 hours ago, ACV92 said:

One other thing, glue for the enclosure.  Back in the day I, and quite a few car audio installers, used Elmer's Wood Glue.  Is Gorilla Glue, or others, better?

I do not build Subs.

I am however in cabinet making/Re-furb/Re-fresh/re-new.

Gorilla is my preference, it's forever. Woodgrain will give before Gorilla gives up it's bond.

Learning curve with Gorilla is, i have a spray bottle set on heavy mist, water insures a full cure and quicker, you spray both sides of your joint, apply Gorilla, join/clamp, and in 10/15 hrs full cure and ready. 

 

>Fine print on the bottle as well as the website states this<

[CECAA850]

Wood glue or PL Premium. 

[totalcomfort]

Tite bond 2 works very well, blue jug. Use it on all my builds. PL fills gaps very well from what Bill says just never used it.

[derrickdj1]

I use Gorilla glue.  A bottle is roughly $5.00.  The I Nuke 6000 DSP amp is a perfect match for what the UM  driver can do and anything more powerful is just going to be unused power.  It appears that some I Nukes produce more fan noise than other.  I've done the fan mod on two and no mod on the other 5.  I did not find the fan to be distracting.  I can't hear it over the TV at normal listening levels.  There are quite a few of us that can help you with the DSP on the I Nuke amp and setup.

[jason str]

If you use wood glue you will probably have to caulk the inside seams to make it absolutely leak proof, its great for doll or bird house construction but not so much when you need an airtight seal.

 

Gorilla glue expands a bit, i use it at times.

 

PL premium X-3 is what i use 99.5% of the time, it expands and its very strong.

[HDBRbuilder]

8 minutes ago, jason str said:

If you use wood glue you will probably have to caulk the inside seams to make it absolutely leak proof, its great for doll or bird house construction but not so much when you need an airtight seal.

 

Gorilla glue expands a bit, i use it at times.

 

PL premium X-3 is what i use 99.5% of the time, it expands and its very strong.

It all depends on the type of material and the type of joinery you use for the assembly...and the type of glue.  I still  use tightbond wood glue...it has proven itself.  WOOD glue actually is SUPPOSED to get into the fiber of the items it is used upon, making the joint stronger than the wood around it!  But I would NEVER use tightbond on an MDF project!  I have personally SEEN WOODEN speaker cabinet assemblies which got trashed, and way more often than NOT, the joint held, but the wood around it came to pieces.  When building with WOOD, I also wipe tightbond into the seams after assembly.  That is why I pre-finish (with a semi-gloss polyurethane) the (plywood) LaScala doghouse assembly itself  and the INSIDE of the bass bin portion(except for the glue joint areas) PRIOR to assembly...I can build the cabinet up and then WIPE more tightbond into the joints of the cabinet, and clean up the extra and NOT leave a "glue line" that would show up if I had waited until AFTER assembly to apply finish.  It takes more time, but it is worth the effort.