[soundemon]

I've tried a couple of DIY subwoofer projects, both of which turned out to be dismal failures. (one was a large transmission line design, the other was dual 300 liter sonosubs tuned to 15Hz)

http://www.avsforum.com/avs-vb/showthread.php?t=1021866
http://www.avsforum.com/avs-vb/showthread.php?t=998500


I'm not sure if the problem was the drivers, amp, methodology etc, but I didn't have the time, cash, or will to swap things around to improve the sound.


I am, however, still interested in making a monster sub. I've got a pretty full woodshop, and decent skill to get the job done. I've been considering the purchase of the elemental designs A7-900. It's ranked #1 on the craigsub list, and I've heard alot of the subs on that list and agree with his opinions.


This sub is interesting becouse they make it very clear the exact drivers and amp they're using, and the tuning frequency. I'd probly use a pair of 6" ports or a trio of 4" ports instead of slot porting, but other than that it seems pretty cut-and-dry.


Anyone with any comments or suggestions on building this sub? I have no problems making it monsterously large, but don't want to make mistakes with the port lenths and configurations etc...


Heres a couple more links to the sub:
http://www.edesignaudio.com/product_...roducts_id=606
http://www.audiojunkies.com/blog/341...0-in-the-works

 

[Luke G]

Could it possibly be the room that is giving you trouble? If that is the case, building another sub probably isn't going to change anything if you put it in the same place the other two were.

 

[soundemon]



Quote:
Originally Posted by Luke G /forum/post/14197034


Could it possibly be the room that is giving you trouble? If that is the case, building another sub probably isn't going to change anything if you put it in the same place the other two were.

Good question, but

#1 it is going to be in a different room (a much bigger one)

and

#2 I've had several comercial subs in my origional room (Velodyne DD10, SVS PB12 ultra, Axiom EP600v2, and M&K MX350) they all sounded great, to a more or lesser degree - even the M&K sounded bette than my dual sonosubs, how sad is that?

 

[ssabripo]

I find it very VERY hard to believe that the two sonotubes did not give you a good result. It leads me to believe that a) you either have a very acoustically challenging room, or b) you have deffective drivers, or a combination of both.


In your LT thread, you mentioned that the SVS Pb12 sounded better than your LT sub, which is curious. To me, it points that the room is not too much of a culprit if your PB12 sounded ok. To me, that points more towards something wrong on the drivers.


Have you ran some sweeps on the driver in air to see if you see any immediate defects?


If your PB12, heck, if your M&K sounded better than your dual sonosubs, I will bet you a soda that there is a 95% chance you have something defective on those drivers, or your power source.


You should start eliminating variables, before you give up.

A) have you tried a different amp, and see if your power plant is the culprit?

B) have you double checked and triple checked your wiring? believe me, even experienced DIYers have screwed up this. The Ava 18's are dual 2 ohms, so you need to wire them in series for a 4ohm load. Have you checked your binding post connectors, make sure you have a good connection?

c) after the above, try running some free air tests on the drivers, to make sure they are ok. Measure their impedance, run sweeps in free air, etc.

 

[soundemon]



Quote:
Originally Posted by ssabripo /forum/post/14197410


I find it very VERY hard to believe that the two sonotubes did not give you a good result. It leads me to believe that a) you either have a very acoustically challenging room, or b) you have deffective drivers, or a combination of both.


In your LT thread, you mentioned that the SVS Pb12 sounded better than your LT sub, which is curious. To me, it points that the room is not too much of a culprit if your PB12 sounded ok. To me, that points more towards something wrong on the drivers.


Have you ran some sweeps on the driver in air to see if you see any immediate defects?


If your PB12, heck, if your M&K sounded better than your dual sonosubs, I will bet you a soda that there is a 95% chance you have something defective on those drivers, or your power source.


You should start eliminating variables, before you give up.

A) have you tried a different amp, and see if your power plant is the culprit?

B) have you double checked and triple checked your wiring? believe me, even experienced DIYers have screwed up this. The Ava 18's are dual 2 ohms, so you need to wire them in series for a 4ohm load. Have you checked your binding post connectors, make sure you have a good connection?

c) after the above, try running some free air tests on the drivers, to make sure they are ok. Measure their impedance, run sweeps in free air, etc.

Hi ssabripo

I tested and trouble-shot to the best of my ability with no success. I've since sold the AVA drivers and Crown K1 amp, and have donated the tubes to someone who thinks they'll be able to make them work.


I had pretty much decided to f*ck DIY and go with only comercial, but I still want a big bruiser. I have my eye on the eD A7-900 but at $2200 plus probly about a million dollars to ship it and pay brokerage/taxes/duties on it i'd consider building again. It looks the 2 drivers and amp come to about $800 and then probly 3 8'X4' sheets of 3/4 MDF will be about $100, and then just my time and effort. Since it a proven design and proven components, I hope I'll have more success.

Comments?

 

[ssabripo]



Quote:
Originally Posted by soundemon /forum/post/14197828


Hi ssabripo

I tested and trouble-shot to the best of my ability with no success. I've since sold the AVA drivers and Crown K1 amp, and have donated the tubes to someone who thinks they'll be able to make them work.


I had pretty much decided to f*ck DIY and go with only comercial, but I still want a big bruiser. I have my eye on the eD A7-900 but at $2200 plus probly about a million dollars to ship it and pay brokerage/taxes/duties on it i'd consider building again. It looks the 2 drivers and amp come to about $800 and then probly 3 8'X4' sheets of 3/4 MDF will be about $100, and then just my time and effort. Since it a proven design and proven components, I hope I'll have more success.

Comments?

listen...let me be very straight forward with you, with all the friendly respect of course!

Like I said, I've had enough experience, and so have plenty of people here, to tell you with 90% certainty that your lack of success in your previous 2 attempts HAD to be due to a defective driver or defective power plant.


Having said that, you want a big bruiser with a $2200 budget? EASY:

option A

* Pair of Maelstrom X18's ($350 each), 4 18" PR's ($120/each), a QSC PLX3402 amp ($800) , a DEQ 2496 ($250), some wood/paint/glue ($100) and you will have two ported subs, tuned to mid-low teens, capable of besting the A7-900 in all areas, including headroom and extension.

option B

go with something like I'm doing

:


*4 x Maelstrom X18's = $350x4 = $1500

*2 x QSC PLX3602 amps = $500x2 = $1000

* DEQ2496 = $250

* 4 x 24"^3 sealed enclosures = $150


this would give you 4 high output sealed 18"s, with tons of placement options for your challenging room. The headroom, extension, and Audio Quality of this would rip the A7-900 a new one

and Of course, you can start with 1/2 the subs ( 2 cubes, 1 amp) and see how it does, and go from there.

 

[soundemon]



Quote:
Originally Posted by ssabripo /forum/post/14198321


listen...let me be very straight forward with you, with all the friendly respect of course!

Like I said, I've had enough experience, and so have plenty of people here, to tell you with 90% certainty that your lack of success in your previous 2 attempts HAD to be due to a defective driver or defective power plant.


Having said that, you want a big bruiser with a $2200 budget? EASY:

option A

* Pair of Maelstrom X18's ($350 each), 4 18" PR's ($120/each), a QSC PLX3402 amp ($800) , a DEQ 2496 ($250), some wood/paint/glue ($100) and you will have two ported subs, tuned to mid-low teens, capable of besting the A7-900 in all areas, including headroom and extension.

option B

go with something like I'm doing

:


*4 x Maelstrom X18's = $350x4 = $1500

*2 x QSC PLX3602 amps = $500x2 = $1000

* DEQ2496 = $250

* 4 x 24"^3 sealed enclosures = $150


this would give you 4 high output sealed 18"s, with tons of placement options for your challenging room. The headroom, extension, and Audio Quality of this would rip the A7-900 a new one

and Of course, you can start with 1/2 the subs ( 2 cubes, 1 amp) and see how it does, and go from there.

Don't worry about offending, I'm looking for all the advice I can get

do you think that a pair of Maelstrom 18's in sealed enclosures will beat the A7-900? specifically I'm looking for depth, clean depth down towards 13 or 14 Hz. Headroom is less of a consideration, if necesary I can add more drivers, more subs. It was my understanding that ported was the way to go for ultra deep subs(?)...

 

[ssabripo]



Quote:
Originally Posted by soundemon /forum/post/14198858


Don't worry about offending, I'm looking for all the advice I can get

do you think that a pair of Maelstrom 18's in sealed enclosures will beat the A7-900? specifically I'm looking for depth, clean depth down towards 13 or 14 Hz. Headroom is less of a consideration, if necesary I can add more drivers, more subs. It was my understanding that ported was the way to go for ultra deep subs(?)...

I don't know if two sealed maelstroms will best the A7-900 in pure headroom. Remember, the a7-900 is a ported large enclosure, so it has the upper hand already in headroom. However, the Maelstrom drivers are much better than the ED drivers, with a good 10mm more of Xmax, and much higher power handling, in addition to the XBL^2 topology. With a QSC PLX3602, you will have a lot more power as well at your disposal, as compared to the plate amp used in the A7-900.



However, with 4 of these, you will obliterate it.

My Point is, start with two...see how they perform. You will be pleasantly surprised. If you still want more headroom, and want deeper extension, build two more, add more L/T to it, and call it a day.

 

[AlexE]

While T-line designs are a guess-and-check affair, sonos should be a well blazed path - this is weird.


Don't give up on DIY, it worked for me and many others. I doubt I'm any more talented than you, I got my hands coming out my azz on most days and I'm lazy to boot. Give it another shot I say...

 

[Ricci]

I've got to agree with Sherv on this one. Must've been something off with the sonotube set-up to get beat by a lowly M&K.


If you wanted a slightly cheaper driver option especially since you are in Canada you could go with 4 IXL18's(Mach5 is Canadian) sealed at $249 ea ($1000). Might not quite be the Maelstrom's but still a nice beefy 18. Put em all in a 24" cube each like suggested. Buy 2 EP2500's for roughly $650. Add prefered EQ, wood etc... Still cheaper than an A7-900.


Sherv,

$500 for a PLX3602

???? Where? I thought they went for more like $850 ea.

 

[AlexE]

Gotta agree with Ricci - you CAN'T miss that way! If you screw up a tune in a t-line or a sono, you have to rebuild it. If you screw up a tune in a sealed box, you reset the filter on the EQ box...

 

[ssabripo]



Quote:
Originally Posted by Ricci /forum/post/14199062


Sherv,

$500 for a PLX3602

???? Where? I thought they went for more like $850 ea.

gotta be patient...look at ebay and craigslist.


one 3602 went for $560 3 weeks ago. a 3402 went for $550 2 weeks ago.

 

[soundemon]

Interesting advice so far everyone - keep it coming. Note here that my main priorities are depth, depth, SQ and depth.


If headroom is a problem I can add more subs. I don't listen at reference volume anyway.


I'd also prefer to use a plate amp instead of a pro amp, to avoid the RCA / XLR switching. I know it "should be" fine, but in the back of my mind I wonder if this is one of the factors leading to my previous failures.


1300wRMS @ 4ohms should do the trick for any of the above mentioned drivers...(?)
http://www.edesignaudio.com/product_...roducts_id=500

 

[ssabripo]



Quote:
Originally Posted by soundemon /forum/post/14199194


Interesting advice so far everyone - keep it coming. Note here that my main priorities are depth, depth, SQ and depth.


If headroom is a problem I can add more subs. I don't listen at reference volume anyway.


I'd also prefer to use a plate amp instead of a pro amp, to avoid the RCA / XLR switching. I know it "should be" fine, but in the back of my mind I wonder if this is one of the factors leading to my previous failures.


1300wRMS @ 4ohms should do the trick for any of the above mentioned drivers...(?)
http://www.edesignaudio.com/product_...roducts_id=500

my friend, you need to throw out all these preconcieved perceptions out of your head!

I suggest you read chasw98's amp measuring thread....you will quickly see how proamps compare to plate amp counterparts. RCA/XLR switching is a problem how? it is just a connection! most of us are using it fine with absolutely zero issues.


here is the internals of the PLX amp:

here is the internals of even the lowly EP2500:

yours truly's semi-good K2's:

and of course, the 1300W plate amp:

like I said, part of the problem with unsuccessful DIY projects are cutting corner tactics, implementation faults, and of course, part defects. In your case, you already are trying to cut corners in this project before it even begins!

Do yourself a favor... just start with 2 maelstroms or 4 IXL's as mentioned, make some sealed cabinets, buy yourself some decent amps, get a DEq2496 to help with EQ and L/T duties, and go from there.


I have a feeling you will be more than fine with that solution, much less with double them!

 

[alexlindeman]



Quote:
Originally Posted by ssabripo /forum/post/14199311


and of course, the 1300W plate amp:

If you are referring to the LT/1300, that is not the amplifier. I think that is the insides of the Bash 1000 watt.


To the original poster: The A7-900 uses 2" thick walls as well.

 

[mgboy]

Ooh alex - show us the insides to the LT1300 if that's not it. =D

 

[ssabripo]



Quote:
Originally Posted by alexlindeman /forum/post/14200399


If you are referring to the LT/1300, that is not the amplifier. I think that is the insides of the Bash 1000 watt.


To the original poster: The A7-900 uses 2" thick walls as well.

would you share with us the interior guts of the LT1300?

 

[alexlindeman]



Quote:
Originally Posted by mgboy /forum/post/14200412


Ooh alex - show us the insides to the LT1300 if that's not it. =D

If you look at the picture's info its from PE's website.


I dont have any pictures at this time, and its not a quick thing to take one, due to the backs being sealed.


Hopefully in the next couple days I will get one.

 

[soundemon]



Quote:
Originally Posted by alexlindeman /forum/post/14200399


If you are referring to the LT/1300, that is not the amplifier. I think that is the insides of the Bash 1000 watt.


To the original poster: The A7-900 uses 2" thick walls as well.

I think they're just doubling up on 3/4" MDF. Amungst the articles I've read on this beast someone mentioned they use 3 layers on the bottom for a total of 2.25" thick.

 

[Chris Schempp]



Quote:
Originally Posted by soundemon /forum/post/14200523


I think they're just doubling up on 3/4" MDF. Amungst the articles I've read on this beast someone mentioned they use 3 layers on the bottom for a total of 2.25" thick.

It's actually 1" MDF all the way through, that beast doesn't touch the 3/4" pile.


Double layered on all walls except the bottom which is triple, so 3" thick.


And yeah, that's a Dayton HPSA1000 that Sherv linked to:

http://www.partsexpress.com/pe/pshow...TOKEN=13610444


We did initial prototyping using some of those 2ish years ago and ran them to the point of death playing Burnout.


If we have time, I'll have Alex get a pic of the guts of an LT/1300.


Back to inventorying.