V, Bosso,

no worries, I will take some max SPL and power compression measurements when I get some time. Hang tight. I myself am curious to see what the limits of this guy is.

I'll be honest and say that right now I am amp limited. With material such as WOTW at -10dB and Happy Feet avalanche scene at -11dB, I'm getting clipping with the drivers still visibly well within it's excursion limits. I may have to get some more amps, even if temporary, to get some more accurate data. Using the K2's will give me an idea, but it will be amp limited measurements.

The system currently is capable of handling pretty much everything I throw at it for spirited viewing/listening. Demanding material (as mentioned before) at -10db will start the clipping, but for the most part I never get that high. I will view movies at -15 from reference at most usually, with music listening around -20 usually.

But I will try to get V's, Mark Seaton's, Bosso's, Noah's, and the rest you guys' curiousty taken care of as time permits. :o



Is the K2 graph that's been overlaid at the same EQ and LT settings as the one with the V5001? I'm thinking it's not? Both of the responses look great, but there doesn't seem to be much difference in the roll off below 10hz. I'd hoped to see what the untouched low end of the 2 looked like compared to each other.
yes, for the most part. The graphs were divided into noEQ and EQ (as described above). the Shelving Filter was always applied to all measurements, as +10dB low shelv @ 20hz, 12dB/Oct.

the one EQ was pretty much the same as well, with the exception of a couple of PEQ points that I had to adjust, but nothing major. The power level changed, but the FR wasn't much different from one measurement to the other on the different amps, specially from 20-80hz

This thread is about Sherv's subwoofer system. It is not limited to the two questions you are most interested in. It is open to anyone who wishes to ask any question, so I did.

Apparently more than a few people are curious what clean SPL level this 4x18 system is capable of in room over its entire bandwidth. I would not call that possessed, just curious. Like it or not, it IS one of many performance parameters that does matter. If it can't beat its way out of a wet paper bag, I don't think it would matter if it was flat from 0hz to 500hz. I'm sure its capable on paper, but measurement data is proof of its limitations. The Hindenburg looked good on paper, remember? :p I just wanted to know where the line in the sand was with respect to uncompressed SPL while he was taking measurements.

Take your time, Sherv, get the important stuff taken care of first. This thread will always be here. Sounds like an amplifier upgrade may be in your future!

Dr V

Of course, there is no censorship of questions occurring, just a simple comment that some of them never cease to amaze me.

Maybe suggesting a safe method for determining 'clean output' in-room over its entire BW is appropriate. Running FR sweeps at progressively higher levels is all but useless. What standard will the results be measured against? How will you know how clean the results are? How will you monitor line sag? How do you monitor a clipped signal from the preamp?

Progressively higher levels of a sine wave sweep will tell you at what point any system will succumb to the torture test that it is, not much more. I sure as heck wouldn't subject my system to that to satisfy your curiosity.

Ricci's progressive sweeps show 3-5dB of compression during the 115dB sweep (an estimate, as it's hard to read details in a 12dB-per-division graph), and his driver is capable of handling a whole lot more sustained input power than the Ava-18. You can exceed the rated power handling of a given driver momentarily, but a 22 second sine wave sweep is anything but momentary without limiters and/or filters and when employing a 10dB boost below 20Hz. How clean are Ricci's sweeps?

Ricci has determined that he'll shorten the sweep length and that he'll lop off the top octave and attempt a higher level sweep. This is a process of trial and error with the possible error part being quite expensive. Especially when Ed, Ilkka, Yates and Nousaine have never gone beyond 4dB of compression (except in the case of subwoofers that have specifically designed limiters to cause compression) and he's already beyond that with the 115dB sweep.

Yates used the progressive sweep and the Linkwitz shaped tone burst tests. As an example of the difference in a 1X15" sealed commercial sub Yates said this of the results of the sweep test..."the response of the S15A at 20Hz never exceeded about 104dB, regardless of how hard I pushed it." He then said this of the results of the boinker test..."In general, the Kleiss's ranking relative to its competitors improved as frequency decreased. Only two of the dozen subs surveyed got the better of it at 20Hz [110dB].

That's a 6dB difference between the 2 tests. With the Genelec, there was a 12dB difference. This explains Ricci's disappointment in the results of his sweep test because his sub will certainly provide more uncompressed output than 110dB during normal program playback.

The Hindenburg metaphor is a good one. Fire up those ACPs because I'm curious to know what it takes to Hindenburg them.

Bosso

Bosso,

I agree with what you are saying for the most part. I don't expect Sherv to push his system to destruction or max things out. He should be able to get a good understanding of what he's got going with a few tests at 75-80%. He should be able to tell when his system is starting to get stressed. I doubt that he will just keep increasing things willie nillie 5dbs at a time. I did push mine hard but I was confident and chose to take that risk.

I will repost my graphs with a 5db division in my own thread so as not to thread jack. I will be taking further measurements sometime this week. I have quite a few questions about what is going on. The compression was never as high as 5db but it did top out at about 4.5db right around 9-11hz. This was the worst area(vent overload combined with driver heat?) The other area showing increased compression was 30-35hz at about 3.3db. Everything else was around 2db or less.

I think the reason for the compression is that the active driver is moving very little at that frequency, and dissipating very little heat. I would watch about how much power you dump in at that frequency.

Maybe suggesting a safe method for determining 'clean output' in-room over its entire BW is appropriate.


http://www.hometheatershack.com/forums/subwoofer-tests/



Fire up those ACPs because I'm curious to know what it takes to Hindenburg them.

Bosso

I never implied that anyone should harm their equipment to please peoples curiosity. That is obviously just something you're fabricating in order to appear to have a clever sounding reply.


Progressively higher levels of a sine wave sweep will tell you at what point any system will succumb to the torture test that it is, not much more. I sure as heck wouldn't subject my system to that to satisfy your curiosity.

Many different subwoofers have been tested for power compression safley using the methods in the above link.(only outdoors instead of indoors). Apparently you lack the confidence that your system could stay together for such a test? :p

I'm just messing around of course. Bosso.. :)

I'll let everyone know how my ACPs sound soon enough. The next 4 weeks is dedicated to the business end of surgery & recovery and thats the most important priority for me at the moment.


Dr V

"Lol" at the link for Bosso to the HTS.

Sherv's preference for low noise floor from the amps warrants a different amp mate. He might be better off with XPA-1 by Emotiva which their testers claim 2kw continuous via 4 ohm load. Their reputation tend to rate their power output conservatively.

For relatively the same price as an American Audio 5001+, the XPA-1 might be the ticket. It comes out in a couple weeks, I am keeping an eye on it because it may have pro-sound output without the pro-sound issues - fan noise, line level boost req's, etc.

Oh yeah, it being aesthetically pleasing is just a bonus :)

Sherv's preference for low noise floor from the amps warrants a different amp mate. He might be better off with XPA-1 by Emotiva which their testers claim 2kw continuous via 4 ohm load. Their reputation tend to rate their power output conservatively.

For relatively the same price as an American Audio 5001+, the XPA-1 might be the ticket. It comes out in a couple weeks, I am keeping an eye on it because it may have pro-sound output without the pro-sound issues - fan noise, line level boost req's, etc.

Oh yeah, it being aesthetically pleasing is just a bonus :)

This amp needs to take a visit to Chuck's test bench.

Wait...this is what Lonnie said on the emotiva forums:

The specs are................
Power output:
500 WRMS into 8 ohms
1000 WRMS into 4 ohms
1350 WRMS into 3.2 ohms
and we are not going to recommend this in any way shape or form but it will do 1.75K WRMS into 2 ohms (but you have to run 220 into it because a 110 v line will not supply enough juice).

THD+N is 0.00086%
Frequency response is from 10-150Khz (-3db) and 20-20Khz (>0.1db)

Weight is the same as the XPA-2.

So, not quite 2kW at 2ohms, and they aren't quite recommending it for use with a 2ohm load...and they say it needs 220v for such a use. Doesn't sound so appealing now.

This amp needs to take a visit to Chuck's test bench.

Chuck's testing methodology is explained, testing
the amp is a good idea. :cool:

But, this is lame.

http://emotivalounge.proboards54.com/index.cgi?board=amps&action=display&thread=1656


Well I finished testing it today so I will throw out a few specs here for everyone.

Here is the official specs:
500 wRMS into 8 ohms at 0.008 THD.
1000 wRMS into 4 ohms at 0.008 THD.

This is a fully balanced amplifier from in to out (which is one of the reasons for the ultra low THD).

24) 250 watt output transistors, so it has a boat load of overload capacity.

1800va transformer (at least that is what I spec'ed, but it looked like a 2KVA, so I will need to do a little more digging.

Un=officially the power ratings are very conservative, I will tell you that under one of my test I measured 1.75K watts RMS, thats right continuous not peak. Don't ask me what the test conditions were because I won't say (we don't want anyone trying it at home) but it did almost 2000 watts without even a grunt. Peak power is off the scale, it has dynamic peaks that are just insane.

We still have a couple of small items to dial in. The frequency response was 5 to 200,000hz (-3db) which means it plays well beyond 500Khz. Now that would turn it into an AM broadcast amplifier and turn your crossovers and tweeters into a smoking, melted pile of metal. So I need to pull it back to around 100Khz and it should be good to go into production.

Other than that she's a beast wrapped in silk. Between 20 to 20khz the frequency response is within 0.125db deviation, so she is as smooth as glass.

If you've got a big swinging pair and your motto is go big or go home, then this is certainly the amp for you.

2KVA transformer can't produce almost 2KW of amplifier
output unless the amplifier is 100% efficient. Is this guy
learning from Face Audio Marketing? 95% efficiency claims
on their amplifiers? :rolleyes: :p


Make sure you don't tell people how you tested the
amplifier either !!! :rolleyes:

Often people fail to test their amplifier properly and
they get exaggerated numbers. :p

I'm not clowning the amplifier in general, it is what it is,
but it's nice to let the consumer in on the real skinny, no
secrets ;)

"2KVA transformer can't produce almost 2KW of amplifier output unless the amplifier is 100% efficient. "

Can't xformers give more than their rating when overloaded by low impedance?

"2KVA transformer can't produce almost 2KW of amplifier output unless the amplifier is 100% efficient. "

Can't xformers give more than their rating when overloaded by low impedance?

Output voltage drops when you exceed the design limits, so you are in the same VA range.

This guy claims "1.75K watts RMS, thats right continuous not peak", it wasn't
some trickery test to try to score more output from the amplifier due it's
capacitor storage. If he said 25mS 1.75K watts, then it would be the capacitors doing this.
If RMS, the capacitors can't sustain this continiously, hence the suspicious claims. Maybe
the 2KVA transformer isn't 2KVA unbeknownst to him ? Or his test method flawed ? I personally don't trust
amplifier tests unless I know the testing method, it's far too easy to make a small error in setup and get
inflated scores. I have seen this in cyber. It's just odd that someone who is designing and/or spec'ing
an amplifier, plus testing it, doesn't see this.

"Output voltage drops when you exceed the design limits, so you are in the same VA range."

But the internal impedance is lower than the loads, so not as fast as current increases.

What are xformer VA ratings based on?

I'd guess thermal; given their mass, they can probably be overloaded for at least a few minutes before overheating.

You have to love those amplifier tests [rms test method] where the amplifier
runs into thermal and/or possible failire problems within seconds just to record
those high scores. :) Wouldn't it be nicer to optimize the testing criteria and
have the amplifier operate for a long period of time, lets say an hour, to get
a better feeling about it ? /heh [all day would be nice]

Look at Chuck's tests and all the thermal / fuse / breaker issues seconds after
starting the test, to capture the high score.

You need a robust design, like a Crest 10001 type [if class H] that
can operate all day at full output without problems. Those are real specs.

"You need a robust design, like a Crest 10001 type [if class H] that can operate all day at full output without problems. "

No, I don't, and neither does anyone else.

If you want to pay extra for continuous capacity that has no bearing on real world operating conditions or sonic performance, that's fine, but I don't and I doubt that most others do.

"You need a robust design, like a Crest 10001 type [if class H] that can operate all day at full output without problems. "

No, I don't, and neither does anyone else.

If you want to pay extra for continuous capacity that has no bearing on real world operating conditions or sonic performance, that's fine, but I don't and I doubt that most others do.

Post your message on the pro sound forum ;)

Tell them to replace their amplifiers with EP2500's
or PE plate amps for bass because in the real world,
nobody needs the extra. :p

People said the same thing when migrating from 100w - 300w plate amps
to 1kw plate amps, to EP2500, to PLX, to CE4000, each progression
offering a reward. Why stop here? Someday people continue the climp upward
for a new discovery. ;)

This thread alone has good information. The K2's are being bested by American Audio. lol

The K2's are being bested by American Audio. lol
what exactly is funny about that?:rolleyes:

the V5001 is heavier, beefier, etc, than the CE4000, and unlike you, I can't (or won't) assume what the internals are but it damn sure is a performer thru and thru (easily powering 4 18" sealed subs).

the K2's only fault is that they could use a little more juice, and have the non-defeatable HP, but as far as performance for a silent amp, they are still very good amps.

The V5001 Should best the K2....nothing funny about it.

what exactly is funny about that?:rolleyes:

the V5001 is heavier, beefier, etc, than the CE4000, and unlike you, I can't (or won't) assume what the internals are but it damn sure is a performer thru and thru (easily powering 4 18" sealed subs).

the K2's only fault is that they could use a little more juice, and have the non-defeatable HP, but as far as performance for a silent amp, they are still very good amps.

The V5001 Should best the K2....nothing funny about it.

reply to post 1764

According to that post, you don't need a robust amplifier. Return the V5001,
return the K2, and go backwards in time and use
your receiver to power your sub. :rolleyes:

Now that it's been established that you like the V5001 to drive
four subs. What if someone "pulls a dirty harriet move" and wants
eight to sixteen subs ? You'd probably use two - four V5001's,
in which case, you can also consider one - two Crest 10001's. :)

But wait.....

No, I don't, and neither does anyone else.

If you want to pay extra for continuous capacity that has no bearing on real world operating conditions or sonic performance, that's fine, but I don't and I doubt that most others do.
__________________
Noah


..... meh ........ ;)

Now that it's been established that you like the V5001 to drive
four subs. What if someone "pulls a dirty harriet move" and wants
eight to sixteen subs ? You'd probably use two - four V5001's,
in which case, you can also consider one - two Crest 10001's. :)

But wait.....




..... meh ........ ;)

If Ssab chose to double the drivers to 8, the V5001 would give the same power to each as it did in a 4X18" configuration.

Suggesting that Noah go to the pro sound forums (because his comment makes too much sense in the forum he's posting in) makes me wonder why you post in this thread?

This is one of the most informative threads of all time. Think before you post and, if your intent is to belittle people like Noah and Sherv, try to have a point.

Bosso

If Ssab chose to double the drivers to 8, the V5001 would give the same power to each as it did in a 4X18" configuration.

True

I can connect 200 woofers to the V5001 and ensure
each woofer gets the same power by proper wiring
and amplifier calibration, ie, 10 watt per woofer [maybe up to 20 watts if the amplifier is up to the task.]

Indeed, you are right ;) :rolleyes:

You can do it your way, but I would do it my way ;)

Suggesting that Noah go to the pro sound forums (because his comment makes too much sense in the forum he's posting in) makes me wonder why you post in this thread?

This is one of the most informative threads of all time. Think before you post and, if your intent is to belittle people like Noah and Sherv, try to have a point.

Bosso

I don't mind debates, but it would be funner to debate
with someone who has Crest 10001 experience. If
you do, raise your hand and discuss, else you have
no grounds for rebuttal ;) :p

The pro sound forum is a great place to get additional
information on pro audio amplifiers because you will
find people with experience.

It would be nice if you read my posts vs. skimming
as you are making erronous accusations.

You seem to have a history of confrontations on this forum.

"Post your message on the pro sound forum"

Makes no difference.

Most modern prosound amps are time-limited at full output, also in recognition of the unwillingness of their customers to pay for continuous power they won't ever use.

this is the science behind it....can't go wrong with trying. Wood is cheap my friend.

YOU TREE KILLERs!!! :D:D:D

bump for ssabripo's SPL charts :D

bump for ssabripo's SPL charts :D
it's gonna be a while I'm afraid....:o.......one of my K2's is not working and needs to be repaired. :mad:

That's no fun. What's the problem and cause? Randomly just noticed it's not working any more, or did it maybe go out while you were pushing things hard?

Silly question, I have no idea if it's in the thread somewhere. If it is, I missed it.

I am trying to model up Sherv's 24" cubes in Unibox and I want to be sure I am looking at the right volume. I have been using 170 liters (with wall lined) as a base for the sealed cubes. Do I have the right amount?

Were you going to use the sound splinters in there scott?

Silly question, I have no idea if it's in the thread somewhere. If it is, I missed it.

I am trying to model up Sherv's 24" cubes in Unibox and I want to be sure I am looking at the right volume. I have been using 170 liters (with wall lined) as a base for the sealed cubes. Do I have the right amount?


http://i111.photobucket.com/albums/n139/its-loud-dude/AVS/Shervins%20Cubes/Volcalc.jpg

Were you going to use the sound splinters in there scott?

Hehe, you know, I am not sure anymore. :p I have been spending too much time modeling both the Sound Splinter and the Maelstrom-X for the past few months. Something about the Maelstrom-X these past couple weeks has got me wanting a pair. I want to match my current RLp's with another pair but now I want to get a Maelstrom really bad. :D So, if you want to know what I think today then that would be to get some Maelstrom's. Right now I have way too many ideas on how to treat the subwoofer setup in my room.

As for now, the idea would be to "try out" a pair of the Maelstrom-X in sealed boxes installed behind my couch while keeping my current mofo's up front. I thought I could experiment with (hopefully) smoothing out my FR response with these Maelstrom-X's since they would be easier to integrate and move around the room. If it turns out that sealed is the way to go for me then I will ditch the big boxes, which I really really really do not want to do.

Having a really hard time prioritizing what equipment needs updating first as you may tell. I've got a hell of a laundry list of new additions to my HT this coming year. Before Christmas this year I plan on acoustically treating my room (FINALLLY!!!!!! WoooHoooo!!!), another pair of surrounds so I can get 7.1 back, and an Emotiva XPA3 for the mains. Should be awesome! :D



http://i111.photobucket.com/albums/n139/its-loud-dude/AVS/Shervins%20Cubes/Volcalc.jpg


Dan! My man! Thank you so much, that's exactly what I needed to see. :D So would you say a good number for Unibox would be around 170-180 liters then? I think that is the close math, Ill go check it now. Thanks again. :)

it's gonna be a while I'm afraid....:o.......one of my K2's is not working and needs to be repaired. :mad:

any updates?

i finally managed to read through the whole thread. it was very enjoyable, well, sometimes it was painful. :) thanks for posting all this great information!

a couple questions came to mind as i was reading:

1. from where did the objective of flat frequency response to 5hz come? i can't quite understand this. if we are trying to recreate the sound effects as applied in the mastering studio and given that mastering studios aren't going to have systems that are flat to 5hz, what is the point of "flat to 5" systems?

2. if the goal is "flat to 5" or something similar, why build the enclosures so small? it would seem that you are just going to run out of amp.

any updates?
the amp is supposed to be ready by mid next week. Crown was off for 3 weeks during the holidays, and the amp got "lost" in their warehouse during thanksgiving. By the end of the month I should be up and running full blast again.

1. from where did the objective of flat frequency response to 5hz come? i can't quite understand this. if we are trying to recreate the sound effects as applied in the mastering studio and given that mastering studios aren't going to have systems that are flat to 5hz, what is the point of "flat to 5" systems?
if you read thru this thread, there were several articles and pieces of info of many new titles containing lots of data points in single digits. Whether the studios are doing this on purpose or not is not clear, but what is clear is that the content is absolutely there.

Additionally, a system that can remain composed lower in the frequency spectrum requires a heck of a lot of power/volume/displacement/etc. Thus, dealing with these subsonic ranges usually means that the audible range is well taken care of ;)

I could go on and on.... there are a lot good tid bits about this in the past 20 pages or so.

2. if the goal is "flat to 5" or something similar, why build the enclosures so small? it would seem that you are just going to run out of amp.
the sealed alignments don't need too much volume....what they need is "help" down low, thru either lots of room gain, or low end boost via a L/T circuit, or a combination of both ;)

With multiple sealed boxes, spread in the best location possible in your particular room, and with enough power, you can get great performance on the very low end with just an L/T boost, as me and bosso and many others have.

Hey, Shervin! Good to see you, man. Hope you had a good holiday season. :)

Did you hear? I will be joining the "sealed" club pretty soon. Should be getting my 2nd pair of RLp18's soon and will probably pick up a BASSIS. After I have four, then it's six, then eight. :D :D :D :D :D :D

Or maybe a quad set of 21's.

:eek:

Hey, Shervin! Good to see you, man. Hope you had a good holiday season. :)

Did you hear? I will be joining the "sealed" club pretty soon. Should be getting my 2nd pair of RLp18's soon and will probably pick up a BASSIS. After I have four, then it's six, then eight. :D :D :D :D :D :D

Or maybe a quad set of 21's.

:eek:
yes, I've been following your comments on Stevenn's thread. Welcome to the "dark" side ;)

Hey, Shervin! Good to see you, man. Hope you had a good holiday season. :)

Did you hear? I will be joining the "sealed" club pretty soon. Should be getting my 2nd pair of RLp18's soon and will probably pick up a BASSIS. After I have four, then it's six, then eight. :D :D :D :D :D :D

Or maybe a quad set of 21's.

:eek:


Scott,

Trying to keep up with the MKTheater'ses? ;)

Mike

Scott,

Trying to keep up with the MKTheater'ses? ;)

Mike

Sssshhhhh. Nobody is supposed to know that. ;)

:p

Sssshhhhh. Nobody is supposed to know that.


I heard that:D Hey! your thinking BASSIS? You are getting serious aren't you.

Best grapher period!

if you read thru this thread, there were several articles and pieces of info of many new titles containing lots of data points in single digits. Whether the studios are doing this on purpose or not is not clear, but what is clear is that the content is absolutely there.

i am aware that the content is there. i am just wondering if the systems that engineers use to master the sound are really flat to 5hz or if they tend to rolloff as frequency gets down that low. i mention this because i have yet to see any reference anywhere to any studio that they have sub-bass capability like you do. :eek:

without knowing what rolloff spec the mastering studios used, it is impossible to know if having subs that are flat to 5hz is providing accurate reproduction or if it is way overemphasizing the subharmonics (but then again, i suppose that can be fun too). that's all i was trying to get at.

i am aware that the content is there. i am just wondering if the systems that engineers use to master the sound are really flat to 5hz or if they tend to rolloff as frequency gets down that low. i mention this because i have yet to see any reference anywhere to any studio that they have sub-bass capability like you do. :eek:

without knowing what rolloff spec the mastering studios used, it is impossible to know if having subs that are flat to 5hz is providing accurate reproduction or if it is way overemphasizing the subharmonics (but then again, i suppose that can be fun too). that's all i was trying to get at.

good question....i'm not sure what the studios can do, but I will bet $.05 that their LFE capabilities do NOT go to 5hz flat; just a guess though ;)

Do artificial LF. Get a parachute, mount it on a baffle,
tie a rope in the center (spring in the rear), pull to get
1hz "wind effect". Amaze the natives. :p

i am aware that the content is there. i am just wondering if the systems that engineers use to master the sound are really flat to 5hz or if they tend to rolloff as frequency gets down that low. i mention this because i have yet to see any reference anywhere to any studio that they have sub-bass capability like you do. :eek:

without knowing what rolloff spec the mastering studios used, it is impossible to know if having subs that are flat to 5hz is providing accurate reproduction or if it is way overemphasizing the subharmonics (but then again, i suppose that can be fun too). that's all i was trying to get at.

From Keith Yates (just one example):

One last point: If you've got the dough and real estate to spare, don't shrug off the sub-20Hz content I've shown in the reference waterfall plots as unintended artifacts—say, scraps of subway rumble or HVAC noise—that somehow slipped through the filters during the mixing process. The content is program-related and meant to be there. So, okay, as a hardware matter, how did the engineers at Todd-AO who snagged an Academy Award for Best Sound for Black Hawk Down monitor all that gut-twisting infrasonic content—all those rumblings I've mentioned that lie just beyond the reach of even refrigerator-sized subs? They used big Bag End subwoofers—22 of 'em.

Bosso

Nice find, Bosso. I've been searching for that quote all night. 22 Bag End 18's. Those were rated to 8hz, btw. ;)

Sherv,
What did you think of the American audio amp? I am thinking of running my subs with the v-6100 or a QSC RMX-5050. What do you think? The QSC is black and would look better in the rack but I really just want to make sure the power is good enough in the bridged 4 ohm mode. Fan noise is not an issue as my equipment is racked and the back is in another cool room. Thanks

Sherv,
What did you think of the American audio amp? I am thinking of running my subs with the v-6100 or a QSC RMX-5050. What do you think? The QSC is black and would look better in the rack but I really just want to make sure the power is good enough in the bridged 4 ohm mode. Fan noise is not an issue as my equipment is racked and the back is in another cool room. Thanks

it worked ok with my subs, as shown previously in this thread, but Chasw98 had some issues with the testing. Ping him or Bosso for details.

OK, thanks

sorry guys for the delay. Bosso is right...I'm so swamped right now, I haven't had time to anything. But here are the 4 main graphs from the measurements earlier this week:

V5001 power TWO subs, left and right side of room:
(this is with LT only, no EQ.....low shelv of 10dB, 12db/oct, at 20hz):
http://i44.photobucket.com/albums/f38/ssabripo/ava18%20sealed%20measurements/8-13-08dual-sealedv5001ltnoeq.jpg

(this is with LT and EQ.....low shelv of 10dB, 12db/oct, at 20hz):
http://i44.photobucket.com/albums/f38/ssabripo/ava18%20sealed%20measurements/8-13-08dual-sealedv5001lteq.jpg


V5001 power all FOURsubs, each pair wired in series for 8ohm load:
(this is with LT only, no EQ.....low shelv of 10dB, 12db/oct, at 20hz):
http://i44.photobucket.com/albums/f38/ssabripo/ava18%20sealed%20measurements/8-13-08quad-sealedv5001ltnoeq.jpg

(this is with LT and EQ.....low shelv of 10dB, 12db/oct, at 20hz):
http://i44.photobucket.com/albums/f38/ssabripo/ava18%20sealed%20measurements/8-13-08quad-sealedv5001lteqapplied.jpg


I will post some comments perhaps tomorrow, as I have to run to a family gathering tonite. One note is that, although the last graph is a beauty in terms of FR, for some odd reason the non-EQ'd (third graph) sounded a bit more natural and accurate.

Also, this amp is amazing in the low end as compared to my K2's, specially with no HP engaged, etc. But the noise floor level was waaaaaaaaaaay up due to the amps fan. This guy is LOUD, and I mean loud....louder than a microwave! Thus, I had to run the measurements hotter than I'd like, but here they are anyways.

I these frequency response graphs very nice.

Did you increase the volume level on sub as it to compensate for the small differences?

May I kindly suggest that you get some long cables to power the input on the amplifier and long cable for the subs that will solve mild amplifier humming and fan noise. You won’t see power amplifiers in cinema auditorium.

While the Bag End subs may be theoretically (or advertised) flat to 8 Hz, that only applies before the protection circuitry kicks in to prevent amps from clipping and woofers from leaving their baskets. In reality the flat response to 8 Hz from a single cabinet is at inaudible levels, unless you're in a telephone booth. Hence, the 22 subs they brought in to monitor Black Hawk Down.

As for checking response, tone bursts seem like a reasonable method. Presumably there's software that will generate 'em over a range of interest. Keep the duty cycle low, and there shouldn't be power compression effects to skew the results.

In a way I agree Black Hawk Down has other LFE.1 track discrete playing that would mask the 8Hz range most likely inaudible be grateful it has content 20Hz and up to cut-off point.

This is just the LFE.1 track ONLY! Where others tend to record from left and right output on there DVD player and you can’t tell what is what because its one whole mess, of other tracks overlapping, expect LFE.1 because LFE.1 isn’t carried on the left and right outputs idiots. sigh

http://www.avsforum.com/avs-vb/attachment.php?attachmentid=130850&stc=1&d=1232712190

I don’t start to hear anything until around a satisfactory 18Hz I might get some movement with sine wave tones from 5Hz going upwards but it really doesn’t start happening until 20Hz right off to cut-off range.

I’m content with 20Hz to 120Hz that is where most of the action is anything less then 20Hz is fantasy you need special speakers or specially deigned rooms designed from top to bottom not an average home with wide open areas where some of the lows is going to travel down.

That is what’s happen your room mate needs to be closed off block the window area up with bricks those bay door windows will be allowing some of the energy to pass though just like a cold winter allows cold to enter into the room.

I have similar issues with double naff glazed windows and you don’t need a sodden phd to figure that some frequencies will be passing though it as well as noise from outside like buses that peak at below 30Hz on the spectrumlab when monitoring. Now then!

I have it figured what to do with layers of thick MDF to reduce it. As to when I start that project, I don’t know but it shouldn’t cost no more than £100.00 pounds.

Tell you what get Spectrumlap rigged up to monitor the whole playback from its low end response with the ECM8000 real easy to monitor the response just make sure you set the gains at right level on the preamplifier and try the test when sound on the outside is very quite otherwise it will be picked up and added to the graph.

And please don’t tell me (I don’t have any noise coming into my room). :D Mate you live in neighbourhood I bet you can hear small single airplanes flying over if they happen to pass overhead lawnmowers cars motorbikes neighbours yelling at each other mate I live in the same type of environment and its noisy.

I get jet aircraft and all other types as I only live 3 miles away from an international airport. I often get the pigs flying hovering overhead and I hate pigs!

I can’t do a REW test until early hours in the morning when there is no traffic around as it will be added to the graph unless I had room that was isolated and had extreme low nose background level from outside interference.

it worked ok with my subs, as shown previously in this thread, but Chasw98 had some issues with the testing. Ping him or Bosso for details.

What has ole Chuck been up to? Haven't seen him around these parts in a long time.

What has ole Chuck been up to? Haven't seen him around these parts in a long time.
busy trying some different changes for his 2chl setup.

FINALLY got my amp back....holy cow, what a difference. I'm back to 4 fully operational 18" sealed subs with 3200W of amplification, EQ + L/T.

life is good

congrats , glad you are back in business !

Nice. Bout time, I say. ;)

FINALLY got my amp back....holy cow, what a difference. I'm back to 4 fully operational 18" sealed subs with 3200W of amplification, EQ + L/T.

life is good

Hey sherv,
What ever came about with the bass and audyssey ? As i remember there was an issue but it escapes me.

KG

It's been a while...what L/T you using.Four 18's I'm jealous:D

IIRC, Sherv was using a Behringer DCX2496 (or was it the DEQ?) for some shelving/boosting of the lowend.

And where do the pics of the build begin.I'm getting dizzy flying through the thread.

Hey sherv,
What ever came about with the bass and audyssey ? As i remember there was an issue but it escapes me.
It's been a while...what L/T you using.Four 18's I'm jealous:D
well, honestly, it is still there, but is a very subjective thing. I'm gonna recalibrate everything, but with DynamicEQ engaged, I'm really liking what I hear with HT sources.

with Music, I'm going 2 channel preamp anyways, so it's all good.

IIRC, Sherv was using a Behringer DCX2496 (or was it the DEQ?) for some shelving/boosting of the lowend.
correct, DEQ2496 with low shelving filter.

And where do the pics of the build begin.I'm getting dizzy flying through the thread.
link is in the 1st post of 1st page, under "phase II":
http://www.avsforum.com/avs-vb/showthread.php?p=11138890#post11138890

I've yet to do the upgrade to DynamicEQ. I'm sure when Mullen comes over he'll talk me into it:D like he did with the 3808ci:D I'm a true follower

Kg

I've yet to do the upgrade to DynamicEQ. I'm sure when Mullen comes over he'll talk me into it:D like he did with the 3808ci:D I'm a true follower

Kg

oh, you might as well just give it up...you will be upgrading for sure!;)

after using 3 different Audyssey products, I can tell you that dynamicEQ is by far their best offering to date. That alone was worth the price of admission on the SC-PR886 processor.

FINALLY got my amp back....holy cow, what a difference. I'm back to 4 fully operational 18" sealed subs with 3200W of amplification, EQ + L/T.

life is good

So close to joining you! I have almost finished building 3 of my 4 24" cubes with the exact same driver configuration (3 Avalanche and 1 Maelstrom on the way). Power in the way of a QSC PLX 3402 and a FACE F1200. Only thing missing for now will be a Bassis or DEQ 2496. I'll have to make due with the EQ options of my Anti Mode -8033 for now. Thanks for the motivation Sherv :)

So close to joining you! I have almost finished building 3 of my 4 24" cubes with the exact same driver configuration (3 Avalanche and 1 Maelstrom on the way). Power in the way of a QSC PLX 3402 and a FACE F1200. Only thing missing for now will be a Bassis or DEQ 2496. I'll have to make due with the EQ options of my Anti Mode -8033 for now. Thanks for the motivation Sherv :)

no nice! I didn't know you were close....that's outstanding! :cool:

you are gonna be in good basshape

FINALLY got my amp back....holy cow, what a difference. I'm back to 4 fully operational 18" sealed subs with 3200W of amplification, EQ + L/T.

life is good

I'm glad your back in the groove Sherv:cool:

i'm glad your back in the groove sherv:cool:

+1

I'm glad your back in the groove Sherv:cool:

indeed. Looking forward to your final impressions as well once you get the ep4000 in place ;)

now, if I could get Bosso to stop being upset at me, and gimme some insight into the decay and timing changes DynamicEQ introduced to the system, i'd be in nirvana :D

DynamicEQ introduced to the system, i'd be in nirvana
You might be shooting for to flat of a curve? I have no problem with the Bassis, well unless I'm holding back the roll-off to far, (timing) but the FBQ2496 I notice right away. I'm sticking with just LT until I can come with another eq option. Whats that new eq that's out now? I cant find the Thread, but it seemed to work well with some of the users that were sensitive to the issues involved with eq?

Well I have 3 of the AVA 18s up and running :) Have not even had a chance to set things up to optimal, but did some listening just with music OMG power and ease like never before. They are not even near corners for any help just all three in a line in front of my screen. Cannot wait to get the Maelstrom in the mix and some EQ to help reach the nether regions. Thanks so much Dan for your cut sheet I was able to build 3 boxes (with everything in else in my schedule) in a couple of days.

gpmbc,
thanks :) , I'm glad the build went well for you. Throw some pics up somewhere for us to drool on ;)

Well I have 3 of the AVA 18s up and running :) Have not even had a chance to set things up to optimal, but did some listening just with music OMG power and ease like never before. They are not even near corners for any help just all three in a line in front of my screen. Cannot wait to get the Maelstrom in the mix and some EQ to help reach the nether regions. Thanks so much Dan for your cut sheet I was able to build 3 boxes (with everything in else in my schedule) in a couple of days.

http://i4.photobucket.com/albums/y110/rx787/OTv5/2h2qo7k.gif

oh, you might as well just give it up...you will be upgrading for sure!;)

after using 3 different Audyssey products, I can tell you that dynamicEQ is by far their best offering to date. That alone was worth the price of admission on the SC-PR886 processor.

Hey Sherv what do you find to be the benefit of dynamicEQ?

Hey Sherv what do you find to be the benefit of dynamicEQ?

the decay and time alignment equalization were the biggest benefits, in addition to what DynamicEQ is supposed to do: keep the EQ levels with changing levels.

In laymen's term, during explosions or giant thumps, the subs stop on a dime! You will see one huge excursion occuring to the drivers and then it is stopped! without it engaged, there is lingering movement which produces that additional reproduction.

At first I was totally turned off by it, as I like my earth shattering bass like anyone else, but once you get used to how quickly the driver's excursion can be controlled, it is much easier on the ears and more pleasant... you can hear bass heavy tracks/movies for extended periods of time without exhaustion.

gpmbc,
thanks :) , I'm glad the build went well for you. Throw some pics up somewhere for us to drool on ;)

Unfinished and temporary placement, still awaiting the Maelstrom-X. Behind the screen are JTR Triple 12LFs.

http://i4.photobucket.com/albums/y110/rx787/OTv5/2h2qo7k.gif

where do you get this stuff...<buckled over laughing>

where do you get this stuff...<buckled over laughing>




+1 its hypnotic.... I can't stop watching it, I laughed so hard.

Who is that guy, I juts can't place him and those bug eyes... :eek::D

is the quad sealed king the last episode :( or will there be a sequel? :)

is the quad sealed king the last episode :( or will there be a sequel? :)

no, this is it for now. Will there be a sequel? who knows in the future, but for now this is it...plenty of headroom, extension, and SQ.

+1 its hypnotic.... I can't stop watching it, I laughed so hard.

+2, Isn't that something:D I've always laughed at the many different little things Sherv has come up with over the years. If I'm not mistaken it started with the Gilligan character pic?
no, this is it for now. Will there be a sequel? who knows in the future, but for now this is it...plenty of headroom, extension, and SQ.
One sub nut to another, imo that's a good honest answer;) This is the first time I have no intention of doing so though. Whats not to like?..

Hey Sherv, do you use any polyfill or other stuffing with your subs?

Hey Sherv, do you use any polyfill or other stuffing with your subs?
yeah...look at the pics earlier in the thread. I used just the normal pink fiber stuff, and not too heavy but just padded the interior all around.

no, this is it for now. Will there be a sequel? who knows in the future, but for now this is it...plenty of headroom, extension, and SQ.

fair enough...i know that i speak for many when i say we are disappointed to see the journey conclude...awesome thread!

http://www.poprox.us/ul/1830-550x-Thumbs%20Up%20Swartz2.jpg

http://www.smh.com.au/ffximage/2006/12/12/borat_thumbs_up_narrowweb__300x504,0.jpg

yeah...look at the pics earlier in the thread. I used just the normal pink fiber stuff, and not too heavy but just padded the interior all around.

From the pics I seen (around page 42) it looked like some other boxes besides the 24" cubes but no biggie there, is it regular fiberglass?

From the pics I seen (around page 42) it looked like some other boxes besides the 24" cubes but no biggie there, is it regular fiberglass?

yep, just regular ol' Homedepot fiberglass rolls.

no, this is it for now. Will there be a sequel? who knows in the future, but for now this is it...plenty of headroom, extension, and SQ.

Unless he wants to come play with the big boys and go IB!

And never fear. The journey is not over yet. He still must tackle the EQ/room acoustics with sophisticated electronics and advancd measuring principles! :) :)

yep, just regular ol' Homedepot fiberglass rolls.

Went today, they had about 5 different thicknesses. Do you happen to remember how thick or the item number R something?

And never fear. The journey is not over yet. He still must tackle the EQ/room acoustics with sophisticated electronics and advancd measuring principles! :) :)
wiser words have never been spoken before! :)

Went today, they had about 5 different thicknesses. Do you happen to remember how thick or the item number R something?
don't worry about the thickness. I bought the 1.5" thick one, and I peeled it in layers...just make sure you apply it to all surfaces evenly and about a good 2" thick and you'll be fine.

wiser words have never been spoken before! :)


don't worry about the thickness. I bought the 1.5" thick one, and I peeled it in layers...just make sure you apply it to all surfaces evenly and about a good 2" thick and you'll be fine.

Thanks

Hi,

I've been reading the diy subwoofer forums for quite a while and I think I'm ready to have a go at building one, but need some help. My main purpose is to build the best I can for music not movies. I currently use an Axiom EP500 but want to see if I can do better.

I really like the idea of the 18" sealed as per this thread. I've read a lot about sealed vs ported and want to have a go at 2 sealed boxes. I'm looking at getting a crown amp (maybe a K2) as it seems to have excellent reviews at handling subs. I want to get some high quality 18" drivers known for accuracy with max power being a secondary consideration. I can plug in the tech specs to the simulators but I don't yet have a good feel as what makes one driver better than another and was hoping someone could advise:) Price right now is not the first consideration as I don't want to limit any options, but of course my funds aren't endless.

Thanks in advance for your help!
-James

Someone put together a list of common diy drivers, but I'm open to any suggestions:
18" Aura NS18

18" lms ultra 5400

18" Mach 5 Audio IXL 18.2.2

18" Mach 5 Audio MJ18

18" Ficar audio Q18

18" Soundsplinter RLp18 D2

18" eD190v2 by Elemental Designs

18" Maelstrom-X by DIY Cable

18" XXX by Resonant Engineering

Hi,

I've been reading the diy subwoofer forums for quite a while and I think I'm ready to have a go at building one, but need some help. My main purpose is to build the best I can for music not movies. I currently use an Axiom EP500 but want to see if I can do better.



Don't be shy, start up a build thread for your project :) This isn't really the place for questions on a new build.

Don't be shy, start up a build thread for your project :) This isn't really the place for questions on a new build.
OK... here it is:) http://www.avsforum.com/avs-vb/showthread.php?t=1156246

I really appreciate any help:) Looks like you guys in this thread are very knowledgeable.

welp, it's been a while, but my DEQ2496 took a dump...so I've been subwooferless for a few weeks.

Debating between a DCX2496, another DEQ, or the MiniDSP.

any input would be appreciated.

Yeah, call me someday if you want to use a DCX2496!! I'll teach you how to program it :)

Chuck

welp, it's been a while, but my DEQ2496 took a dump...so I've been subwooferless for a few weeks.

Debating between a DCX2496, another DEQ, or the MiniDSP.

any input would be appreciated.

If your amps do not need more the 2V to reach max output then the MiniDSP balanced 2x4 version is the perfect solution and has more functionality then the other choices.

Yeah, call me someday if you want to use a DCX2496!! I'll teach you how to program it :)

Chuck

Chuck!!! Welcome back!!! Did you read my PM on Htguide? Im wondering if you still measure amps? I have a few I want to ship you.

Thanks
Doug

welp, it's been a while, but my DEQ2496 took a dump...
I hope mine still works. I probably haven't used it since you last posted in this thread.

The DCX kicks ass!

One of the best purchases I have ever made.

if chuck would call me back, we could be trying this thing... :p