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First build - Octo SI 18's with flat packs. - Page 12

post #331 of 790
Thread Starter 
Thanks Scott and Ratm, my thoughts exactly.

I haven't completely thrown in the towel on flat bass yet though. When I move have of my subs to the rear part of the room the curve should be smoother and I won't have to do so much massive pulling down with eq (I pulled down 14.9 at 30h with a q of 1.2!!!!)

So, maybe in that configuration I'll get all the bass feeling I can handle before the evil little red light begins to flicker and at the same time have flat bass. smile.gif
post #332 of 790
Which minidsp did you get? I found after plugging mine in and flattening the response my subs sounded like crap, no dynamics or anything. Then I found I had been clipping its inputs, I redid the gain structure and all was better.
post #333 of 790
Thread Starter 
Quote:
Originally Posted by ratm View Post

Well said Scott! And Carp, again, great post. There are far, FAR more knowledgeable peopl on here, but for me, my ears will almost always trump measurements.

Yep - the biggest difference though wasn't the ears it was the feeling - man, so much impact tactile bass. Pretty nuts. I can see why Bass Love You is used so much as a demo song, now that the LT is in place those low "notes" are really cool too. The Submersive tried to play it, but just not enough of them to experience what I'm getting now.
post #334 of 790
Quote:
Originally Posted by mtg90 View Post

Which minidsp did you get? I found after plugging mine in and flattening the response my subs sounded like crap, no dynamics or anything. Then I found I had been clipping its inputs, I redid the gain structure and all was better.

I did talk to him about checking the input and output levels but I don't think he's done it yet. You definitely need to do that carp and remember that what reads as "-6dB" is clipping. Otherwise none of the various eq comparisons are really valid.
post #335 of 790
Consider still that maybe you should pick up another amp in the near future. I think some of that lack of impact was because you had a massive boost in the area where your woofers will want and absorb well...massive amount of power. The area that you pulled down (~30hz) is the exact area that your drivers are resisting current from your amp and they are at their most efficient. So there is a huge swing in power there. Also, the 30hz area is usually the most impressive sounding to most people. I personally LOVE the 15-30hz octave but any lower and it's just jiggles and possible smooth waves of bass that don't really have any sound whatsoever. You should probably go do some A-B testing with more movies that have 5-20hz bass. Bass I Love You? rolleyes.gif Yawn. Test some real dynamic events in movies.

Another consideration would be some nearfield or side/rear bass units. A guarantee a quad set cubed up of these 18's would bring in that visceral feeling right back. smile.gif
post #336 of 790
Thread Starter 
Quote:
Originally Posted by mtg90 View Post

Which minidsp did you get? I found after plugging mine in and flattening the response my subs sounded like crap, no dynamics or anything. Then I found I had been clipping its inputs, I redid the gain structure and all was better.

I got the balanced kit. Actually the one I have now is mrsmithers, but he has the same one. We checked for clipping on the input gain button (just left of the parametric eq button) and it looked fine so I don't think that's the problem.
post #337 of 790
Ok just wanted to make sure it was not the same problem I had as your description of it sounded similar.

Edit: Jumper is on 2v setting right?

Edit Edit: Looks like that should be default setting never mind.
Edited by mtg90 - 3/21/13 at 9:58pm
post #338 of 790
I agree with the previous posts, just blast it the way you like it and don't worry about the measurements.

Awesome stuff Carp, very impressive system!
post #339 of 790
Quote:
Originally Posted by carp View Post

I got the balanced kit. Actually the one I have now is mrsmithers, but he has the same one. We checked for clipping on the input gain button (just left of the parametric eq button) and it looked fine so I don't think that's the problem.

We looked at it briefly but not at any kind of volume. Just turn the amp off and run a couple different frequency test tones and see how high you can go. Program content isn't great for checking levels on the miniDSP.
post #340 of 790
Thread Starter 
Quote:
Originally Posted by MrSmithers View Post

We looked at it briefly but not at any kind of volume. Just turn the amp off and run a couple different frequency test tones and see how high you can go. Program content isn't great for checking levels on the miniDSP.

I just put on track 18 from the omnimic disk turned off the amp and turned the receiver as loud as it would go and the numbers only got to the 50's.

Another reason I don't think clipping is the issue is that I was still using the minidsp LT for that blue curve above when I went nuts on Bass I Love you and no clipping on the amp at all.

BTW, after you left I noticed the dreaded hum. It's not there without the minidsp but obvious with it and became more so the longer I've been tinkering. I hope there is a way to get rid of it.
post #341 of 790
Thread Starter 
Quote:
Originally Posted by Scott Simonian View Post

Consider still that maybe you should pick up another amp in the near future. I think some of that lack of impact was because you had a massive boost in the area where your woofers will want and absorb well...massive amount of power. The area that you pulled down (~30hz) is the exact area that your drivers are resisting current from your amp and they are at their most efficient. So there is a huge swing in power there. Also, the 30hz area is usually the most impressive sounding to most people. I personally LOVE the 15-30hz octave but any lower and it's just jiggles and possible smooth waves of bass that don't really have any sound whatsoever. You should probably go do some A-B testing with more movies that have 5-20hz bass. Bass I Love You? rolleyes.gif Yawn. Test some real dynamic events in movies.

Another consideration would be some nearfield or side/rear bass units. A guarantee a quad set cubed up of these 18's would bring in that visceral feeling right back. smile.gif

Good ideas Scott.

I did do bass heavy scenes, not just bass I love you. The beach scene from x-men has crazy low stuff and was the only scene that has ever made my Submersive make a bad sound and that's what I was mostly testing with tonight along with Iron Man 2, Underworld scenes etc.

Scott, play Bass I Love you at 15+ hot at reference and it's no more yawning!! biggrin.gif

Yep, the next step is trying subs on the side wall again. I just have to get help getting the top sub down. I suppose I could do it myself, it would be easier than stacking it was but that makes me nervous.
post #342 of 790
Quote:
Originally Posted by carp View Post

Thanks Scott and Ratm, my thoughts exactly.

I haven't completely thrown in the towel on flat bass yet though. When I move have of my subs to the rear part of the room the curve should be smoother and I won't have to do so much massive pulling down with eq (I pulled down 14.9 at 30h with a q of 1.2!!!!)

So, maybe in that configuration I'll get all the bass feeling I can handle before the evil little red light begins to flicker and at the same time have flat bass. smile.gif

I noticed the same thing with my mini settings that were cutting instead of boosting towards flat. I really had to crank the volume and gains in other parts of the chain to get volumes I wanted.

Have you read the comments Bosso wrote in Papas thread about the settings of the back switches on the clones when using the mini? I havent tested his advice yet but it does make a light bulb go off in my head like oh yeah that makes sense! If havent read them just look at like 3 pages back I think.
post #343 of 790
Quote:
Originally Posted by MrSmithers View Post

I didn't make a thread or take any pictures. I can when I put carp's together. Basically I just put it in a 1U rackmount case so that it can go in a rack (someday when I have one!) and have the connectors on the back side be the only thing visible. I had no interest in paying extra for their "boxed" solution that still doesn't do a bit of good since you still have to use those Phoenix terminal to XLR connectors (or similar) and then are left with this form factor that isn't really conducive to anything. Just personal preference really, but I like having it all enclosed and neat-like.

Much appreciated my good sir!

Quote:
Originally Posted by carp View Post

Ok, did a lot of playing around with the minidsp tonight. What I have found is that I do not like flat bass, or at least so far I don't.

So here is the comparison. The blue line sounds/feels so crazy good and the red line is nice but underwhelming and doesn't do it for me.

Hear you man. I'm not the biggest fan of "flat" as well... I've learned that I like all of the infrasonic stuff (2Hz - 14Hz) waaaay higher then the 15-25Hz stuff and I like the 15-25Hz higher then the 26-40Hz stuff...

Hey, you ever figure hot how to fix the OM snapshot settings? Maybe when MrSmithers stops by your place next time you guys can figure out how to change from 10db increments.Guess its moot at this point, but I'd like to know why your OM is defaulting to 10db increments to begin with.

Quote:
Originally Posted by Scott Simonian View Post

Consider still that maybe you should pick up another amp in the near future. I think some of that lack of impact was because you had a massive boost in the area where your woofers will want and absorb well...massive amount of power. The area that you pulled down (~30hz) is the exact area that your drivers are resisting current from your amp and they are at their most efficient. So there is a huge swing in power there. Also, the 30hz area is usually the most impressive sounding to most people. I personally LOVE the 15-30hz octave but any lower and it's just jiggles and possible smooth waves of bass that don't really have any sound whatsoever. You should probably go do some A-B testing with more movies that have 5-20hz bass. Bass I Love You? rolleyes.gif Yawn. Test some real dynamic events in movies.

Another consideration would be some nearfield or side/rear bass units. A guarantee a quad set cubed up of these 18's would bring in that visceral feeling right back. smile.gif

IRENE!!!!
post #344 of 790
F**kin' Irene! biggrin.gif
post #345 of 790
Wait guys, do you mean flat bass vs hot bass? I don't like peaky bass at all and love a flat response. However, I do love running that flat response hot. Meaning my 4-120hz is +/- 2.5 dBs but 10 dBs hot from 120hz and above. There are effects in Transformers ROTF that you don't even feel unless you run the sub hot but without it being flat it sounds off to me. Run your subs flat like you show but then with it flat turn up the LFE channel 10 dBs then thank me later.
post #346 of 790
Quote:
Originally Posted by MKtheater View Post

Wait guys, do you mean flat bass vs hot bass? I don't like peaky bass at all and love a flat response. However, I do love running that flat response hot. Meaning my 4-120hz is +/- 2.5 dBs but 10 dBs hot from 120hz and above. There are effects in Transformers ROTF that you don't even feel unless you run the sub hot but without it being flat it sounds off to me. Run your subs flat like you show but then with it flat turn up the LFE channel 10 dBs then thank me later.

+1. Carp has ACTUAL flat response--as in flat from 9 to who-knows-where. With as much headroom as you have, Carp, turn your LFE channel up and enjoy!
post #347 of 790
I like a smooth response, .. no peaky stuff.

However, similar to others, for me there's a strong subjective appeal to a somewhat sloping response (regardless of playback level within sane norms).

Smooth, absolutely necessary IMO for adequate resolution and delineation of the material. Decay, tight decay times have an equally as strong subjective appeal (maybe even greater).


It's all about the room, the room's all about the time domain. That's sig worthy, I intend to do that sometime .. smile.gif
post #348 of 790
Quote:
Originally Posted by Scott Simonian View Post

F**kin' Irene! biggrin.gif
Or as my wife woud say, "Mutha F'n IRENE!!! biggrin.gif
Quote:
Originally Posted by MKtheater View Post

I don't like peaky bass at all and love a flat response. However, I do love running that flat response hot. Meaning my 4-120hz is +/- 2.5 dBs but 10 dBs hot from 120hz and above.
+1
Try this out for a while Carp and see how you like it. Sometimes it just takes a bit getting used to the way "flat bass" sounds. Personally, i think you'll pick up on all the subtle details in the music/sountrack running your system flat. I know that if i switch my settings to bump up that mid section, it almost sounds boomy (for lack of a better word) to me.
post #349 of 790
I have something for you guys to try. Put in Transformers ROTF and start it at the scene where the autobots and military are rescuing Sam so he can revive Optomous. Run that scene flat all the way, meaning flat response and subs flat, even 2-3 dBs hot if you wish. Then run that scene 10 dBs hot and you will notice many more pulse waves that hit you which never did before. I mean there are at least 6 waves that are very cool effects and don't even notice any of them but the last one when running flat. I would have never even known this was happening until I had the DTS10's. The DTS10's in my room naturally runs the 8-20hz stuff hot in my room so when I was trying them out I all of a sudden felt all these bass waves(this was the big movie that came out at the time) which never happened with my eD sealed 190v2 system so I automatically sold them off and kept the DTS10's. Now I have realized to get this same effect with a sealed system(CHT subs) I need two things, boost down low and run the subs 10 dBs hot compared to the DTS10's only 3 dBs hot. Fast forward to my current system which should have less output compared to 18's and such and I can get the same effect doing one or the other. If I run my subs 10 dBs hot I get this same effect really pronounced or I can boost the low end a little and get it as well, I don't need both. I am on concrete so maybe I need a little more than most but try it. Once you feel ever blast bass wave you won't go back.
post #350 of 790
Thread Starter 
Quote:
Originally Posted by carp View Post







Now, looking at that you might be thinking, well sure you have more bass with the blue line so of course that will seem better - but here's the thing. I ran both settings hot and loud until I got clip lights - well actually that's not true. I never clipped with the blue line!! That's the whole thing I've been after, I gave in before my amp/subs did!! With the red line setting I clipped before I cried uncle.

Ha, oh one other thing. Earlier today Kevin and I did discover that one of the 8 subs was out of phase. It was easy to spot during the x-men scene because the drivers were moving so slow in parts. That throws off all of my measurements from before - damn.

It didn't make a massive difference but it did smooth things out some.


Guys, I was running the bass hot when it was flat. I saw a red flicker on the clip light before it was enough bass using the red line or flat setting. With the eq turned off but LT left on (blue line) I never saw a flicker at all on the clip light and it was enough bass for me - and that's saying a lot!!

I really think that its the 14.5 db pulldown over a massive area that causes the problem. I bet when I move 4 of the subs to the back half of the room it will be flatter and I'll be good to go. I plan on doing that today.
post #351 of 790
Well a 12 dB peak at 28hz will cause a huge difference in bass.
post #352 of 790
Thread Starter 
Here's something else that happened last night.

Kevin had built me a relay so that my CV amp will shut on and off when I turn on and off my receiver - how cool is that by the way. Well, during the x-men scene my amp suddenly shuts off the instant a clip light flickers for the first time. I was way above reference when this happened, I think I was reference on master volume subs 10 hot. I also had the LT boost (12.7 gain) plus another low shelf boost of +4.5 at 18hz with a q of 2. That's what it takes to get me flat down low - I guess that's part of the problem.

So anyway, the amp goes off and I'm panicking thinking I killed my amp already. My next thought was maybe the relay somehow caused the problem so I go back and unplug the amp from the relay and plug it straight into the wall again and boom, back in business.

Well, it didn't occur to me until just now that I might have actually tripped the breaker the relay power cord was plugged into. Sure enough that's what happened. The only thing on that line was the CV amp.

I'm relieved that my relay still works but pissed that I tripped a breaker.

I just had 2 dedicated 20 amp lines put in a few weeks ago to make sure I would be good to go. Evidently that wasn't enough. Damn Damn Damn. I should have had them run 30 amp lines... I know they ran 12 gauge wire but it's not enough. Hmmmm well I guess I could get another amp so that I have one amp plugged into each dedicated line. Would that work for how I have my subs wired? I have D4's and currently running 4 drivers off of each channel of the amp in paralllel for a 2 ohm load.

So, 2 CV amps with 2 subs each per channel? Does that work?

Also, could the relay cause an issue? The rest of the night I was using the other dedicated 20 amp line which the receiver and all components share and didn't trip the breaker. I was still going nuts with the volume and flickered the clip light a couple more times and no breaker shut off.
post #353 of 790
I don't understand something, you were happy with two submersives or 4 15's running 10 dBs hot. Now with 8 18's you need a 13 dbs boost plus another 5 dBs boost down low to be happy? Did you boost the submersives? What were the measurements for them? Boosting that much and 10 dBs hot will shut down the amps with no problems. Oh, running flat does take displacement and power to do it right. You are running way past normal so it will take even more. People you say yeah I have one or two subs doing it all at 10 dBs over reference with no problems are either not flat or not getting any low end. Or running in a broom closet.
post #354 of 790
Quote:
Originally Posted by MKtheater View Post

Wait guys, do you mean flat bass vs hot bass? I don't like peaky bass at all and love a flat response. However, I do love running that flat response hot. Meaning my 4-120hz is +/- 2.5 dBs but 10 dBs hot from 120hz and above. There are effects in Transformers ROTF that you don't even feel unless you run the sub hot but without it being flat it sounds off to me. Run your subs flat like you show but then with it flat turn up the LFE channel 10 dBs then thank me later.

I can't speak for Carp, but I'm saying I would prefer this.... (thanks Dave!)



vs flat. I'm basing that on my limited experience with super systems. Some would argue this graph is pointless and the never ending debate of the human hearing threshold should just be left alone:



...but until I can replicate a similar curve to experience ULF ridiculousness on that level, I can't give up on it.
Edited by popalock - 3/22/13 at 9:02am
post #355 of 790


http://www.avsforum.com/t/980916/official-classe-ssp-800-thread/3510#post_19350155

jbl/harman has probably spent more money and performed more research than anybody on subjective sound preference. here is the target curve for their top of the line home theater system:



so don't feel like you are an oddball if you like a rising bass response. :-)
post #356 of 790
Yes, but I believe that Dave runs his system flat with that house curve? If so then running the subs flat and then 10 dBs hot will be the same levels(5-20hz). So not only will you feel all the same stuff the flat curve will pound you more with midbass. That low stuff is felt and whether you have lots of midbass or not I still feel it and it is not masked. Just my opinion though. I am just saying that with all that boost and 10 dBs hot you are going to shut down those amps for sure. You do realize how much power you are asking for to do that? So my question again, how did you even like the submersives which has much less displacement and could not play as loud than these 8 18's? If you were happy with them at 10 dBs hot without boost(why you can run them 10 dBs hot) then why are you boosting these? I understand the need for perfect graphs but in the end it is the movie and for you the music experience that counts.
post #357 of 790
Thread Starter 
Quote:
Originally Posted by MKtheater View Post

I don't understand something, you were happy with two submersives or 4 15's running 10 dBs hot. Now with 8 18's you need a 13 dbs boost plus another 5 dBs boost down low to be happy? Did you boost the submersives? What were the measurements for them? Boosting that much and 10 dBs hot will shut down the amps with no problems. Oh, running flat does take displacement and power to do it right. You are running way past normal so it will take even more. People you say yeah I have one or two subs doing it all at 10 dBs over reference with no problems are either not flat or not getting any low end. Or running in a broom closet.

This is nothing like the dual Submersives, it's way more impressive. However it should be and my expectations are much higher so my comments have not been a comparison to my old sub setups. I am searching for no limits other than myself and I still may have it I just need to tinker a lot more.

It seems that my room has horrible gain down low and I'll just have to deal with that. If I have to buy more subs in the future so be it.
post #358 of 790
Quote:
Originally Posted by carp View Post

This is nothing like the dual Submersives, it's way more impressive. However it should be and my expectations are much higher so my comments have not been a comparison to my old sub setups. I am searching for no limits other than myself and I still may have it I just need to tinker a lot more.

It seems that my room has horrible gain down low and I'll just have to deal with that. If I have to buy more subs in the future so be it.

Maybe you just need a more powerful amp to give you that extra headroom? I never ran that much boost in my room with the subs hot so I don't know what would happen. I do know that boosting that high has it's limits for sure. What is the sensitivity at 10hz with your system? How loud are you trying to play at 10hz? This will let you know how much power is needed to do so. I say if it sounds good to you without a perfect flat response and you are not clipping at the levels you want then just leave it.
post #359 of 790
carp, before you get too crazy with things, we need to loopback your receiver again since we apparently didn't save it last time. From what I recall it wasn't great (relative to my cheap Onkyo at least) and I think we need to know if that's the case.
post #360 of 790
Quote:
Originally Posted by LTD02 View Post



http://www.avsforum.com/t/980916/official-classe-ssp-800-thread/3510#post_19350155

jbl/harman has probably spent more money and performed more research than anybody on subjective sound preference. here is the target curve for their top of the line home theater system:



so don't feel like you are an oddball if you like a rising bass response. :-)

True except Dave's curve starts to rise at 20hz rather than start coming down. He likes a rising curve but just for the low stuff. Carp's is just a broad peak at 28hz and not a rising curve.
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