My Dual 15" Dayton HO How should I build it Thread? - Page 3 - AVS Forum
Forum Jump: 
Reply
 
Thread Tools
post #61 of 87 Old 11-08-2012, 09:59 PM - Thread Starter
Senior Member
 
Evolvo's Avatar
 
Join Date: Jan 2008
Location: West Michigan
Posts: 229
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
Here are my mockups of port velocity. I did 5.750 Cu Ft Box, Tuned to 18.37 hz, 2nd order Buttorworth @ 19hz, 2 X 3" X 18.25" Ports. The first one is 200 watts and the 2nd 400 watts. Its between 20 and 28 m/s. Don't know if that's considered bad or not, but I can't tell if it is. Some people say it can be higher without problems and some people say it should be lower, but sounds good to me.


Evolvo is offline  
Sponsored Links
Advertisement
 
post #62 of 87 Old 11-24-2012, 02:01 PM - Thread Starter
Senior Member
 
Evolvo's Avatar
 
Join Date: Jan 2008
Location: West Michigan
Posts: 229
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
So I have to give my friend back his ep 2500 and need a new amp for my subs. I was thinking the 3000 berry inuke amp with dsp or buying 2 500 watt yung plate amps. With the inuke im wondering what is the lowest u can set high pass frequency at cause i need to do about 17hz. Also im wondering would the fact the inuke has higher input sensitivity than home gear cause me problems. The ep2500 did not. Im thjnking the plate amps might be to week to eq properly .
Evolvo is offline  
post #63 of 87 Old 11-24-2012, 02:45 PM
AVS Addicted Member
 
LTD02's Avatar
 
Join Date: Oct 2003
Posts: 16,199
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 233 Post(s)
Liked: 947
go for the inuke 3000 w/dsp. even though the corner on the highpass can't be lower than 20hz, there are some ways to fudge it and get pretty much the same result.

Listen. It's All Good.
LTD02 is online now  
post #64 of 87 Old 11-24-2012, 03:27 PM - Thread Starter
Senior Member
 
Evolvo's Avatar
 
Join Date: Jan 2008
Location: West Michigan
Posts: 229
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
What about the sensitivity level difference, is that going to be pretty much the same as with the EP2500. Man I don't want to spend that kind of money, but if I have to I will. I see a EP4000 on craigslist for 200, hope i can pick that up. If I were using the Inuke does that mean I would no longer need my feedback destroyer.
Evolvo is offline  
post #65 of 87 Old 11-24-2012, 03:40 PM
AVS Addicted Member
 
LTD02's Avatar
 
Join Date: Oct 2003
Posts: 16,199
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 233 Post(s)
Liked: 947
if you go with the ep4000, what is your highpass solution? i dug through the feedback destroyer manual when we were talking a while back and i didn't see any high pass filter functions.

wait, are you the guy who ran the rumble filter on the amp up around 30-35hz and then just eq'd up the bottom end with the bfd?

Listen. It's All Good.
LTD02 is online now  
post #66 of 87 Old 11-24-2012, 03:46 PM - Thread Starter
Senior Member
 
Evolvo's Avatar
 
Join Date: Jan 2008
Location: West Michigan
Posts: 229
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
Quote:
Originally Posted by LTD02 View Post

wait, are you the guy who ran the rumble filter on the amp up around 30-35hz and then just eq'd up the bottom end with the bfd?

Lol, yeah that's me. I'm pretty sure the way I'm doing it, I'm probably losing some DB's with the amt of EQ I'm doing to bring the rest of the frequency range above 30hz down to where 20hz is, but with the EP4000, my crazy process may sound better with the more powerful amp.
Evolvo is offline  
post #67 of 87 Old 11-24-2012, 03:53 PM
AVS Addicted Member
 
LTD02's Avatar
 
Join Date: Oct 2003
Posts: 16,199
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 233 Post(s)
Liked: 947
sorry, there are so many builds it is difficult to keep track of what everybody is doing in my head.

stick with your method. i would not have thought that it could work so well, but i modeled it up a few different ways and it seems to work just fine.

just make sure that you test that craigslist amp before your turn over the cash. lots of jokers in the secondary market.

example: a high pass filter at 35hz, 2nd order butterworth combined with a parametric eq at 20hz +9db q=2 gives a flat frequency response with a -3db point of around 18hz.

you probably don't need that much eq because of boundary and pressure vessel gain, but it was a bit of an eye opener to me.

Listen. It's All Good.
LTD02 is online now  
post #68 of 87 Old 11-24-2012, 03:56 PM - Thread Starter
Senior Member
 
Evolvo's Avatar
 
Join Date: Jan 2008
Location: West Michigan
Posts: 229
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
Thanks for the advise, I'll definitely test the crap out of it.

Is there a way to ultimately tell what your sub is tuned to, so that you can put the high pass filter at the correct frequency?

Should your HPF be set at the same frequency as your tuning frequency?

Given that price was the same for both processes, would you go with the more powerful ep 4000 using my process or the inuke?
Evolvo is offline  
post #69 of 87 Old 11-24-2012, 04:17 PM
AVS Addicted Member
 
LTD02's Avatar
 
Join Date: Oct 2003
Posts: 16,199
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 233 Post(s)
Liked: 947
"Is there a way to ultimately tell what your sub is tuned to, so that you can put the high pass filter at the correct frequency?"

without any gear, you can run some test tones and watch the cone motion. at tuning, the cone will move little. above and below it will be moving much more.

"Should your HPF be set at the same frequency as your tuning frequency?"

it doesn't have to be exact. at tuning or a little lower is common.

"Given that price was the same for both processes, would you go with the more powerful ep 4000 using my process or the inuke?"

they actually output about the same real power, approximately 2000 +/- watts from both amps. with a 4 ohm driver on each channel, you'll get around 650 +/- watts or so into each driver.

Listen. It's All Good.
LTD02 is online now  
post #70 of 87 Old 11-24-2012, 04:36 PM - Thread Starter
Senior Member
 
Evolvo's Avatar
 
Join Date: Jan 2008
Location: West Michigan
Posts: 229
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
Quote:
Originally Posted by LTD02 View Post

"Given that price was the same for both processes, would you go with the more powerful ep 4000 using my process or the inuke?"
they actually output about the same real power, approximately 2000 +/- watts from both amps. with a 4 ohm driver on each channel, you'll get around 650 +/- watts or so into each driver.

So then that means the Inuke 3000 is more powerful than the EP2500. I thought the ep2500 was on the same level as the inuke. I'm suprised by that, I guess I haven't officially read the stats. I was more or less just looking at pricing.

As far as the HPF goes, "does 2nd order buttorworth mean 12db per octave dropoff"?

I've seen 4th order which seemed to drop at a faster rate, at what point is 4th order necessary?
Evolvo is offline  
post #71 of 87 Old 11-24-2012, 05:03 PM
AVS Special Member
 
Stereodude's Avatar
 
Join Date: Jan 2002
Location: Detroit Metro Area
Posts: 9,905
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 494 Post(s)
Liked: 530
Quote:
Originally Posted by Evolvo View Post

As far as the HPF goes, "does 2nd order buttorworth mean 12db per octave dropoff"?
Yes a 2nd order butterworth filter has a 12dB per octave slope.
Quote:
I've seen 4th order which seemed to drop at a faster rate, at what point is 4th order necessary?
If you can bottom out the driver below the tuning point with the 2nd order you can either move the HPF up in frequency or steepen it. It's a little trial and error.
Stereodude is offline  
post #72 of 87 Old 11-24-2012, 05:17 PM
AVS Addicted Member
 
LTD02's Avatar
 
Join Date: Oct 2003
Posts: 16,199
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 233 Post(s)
Liked: 947
"So then that means the Inuke 3000 is more powerful than the EP2500."

the ep4000 is pretty much the same thing as the ep2500.

all three amps have pretty much the same real power output.

Listen. It's All Good.
LTD02 is online now  
post #73 of 87 Old 11-24-2012, 05:25 PM - Thread Starter
Senior Member
 
Evolvo's Avatar
 
Join Date: Jan 2008
Location: West Michigan
Posts: 229
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
Quote:
Originally Posted by Stereodude View Post



If you can bottom out the driver below the tuning point with the 2nd order you can either move the HPF up in frequency or steepen it. It's a little trial and error.

This kinda opens another can of worms for me. I didn't know bottoming out factored in to this. So taking from the statement you just made I'm going to make an assumption and you can tell me whether this is right or not.

I knew that I needed an HPF so that the woofer would not extend pass Xmax and move to far in or out. I'm guessing the term for this is called bottoming out. Assuming that statement is right, I never really new that term meant that. I thought you could damage a woofer without knowing it, meaning that the woofer could be flopping while playing loud music and you would not know that it was flopping. I thought bottoming out meant something else.

So just for clarification will you definitely know if you need a HPF by hearing the sound of the woofer bottoming our or could you still be damaging woofer without knowing it?

You say trial and error, so also I'm assuming that the sub bottoming out once or twice is not a problem, but constant bottoming out would eventually damage woofer?
Evolvo is offline  
post #74 of 87 Old 11-24-2012, 05:38 PM
AVS Special Member
 
Stereodude's Avatar
 
Join Date: Jan 2002
Location: Detroit Metro Area
Posts: 9,905
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 494 Post(s)
Liked: 530
Quote:
Originally Posted by Evolvo View Post

So just for clarification will you definitely know if you need a HPF by hearing the sound of the woofer bottoming our or could you still be damaging woofer without knowing it?
It depends on the driver. Some will make a mechanical clank or clack sound when bottomed out (from the motor running into something). Some will dent the cone and cause the glue to fail and things will come apart. Others will start to make mechanical noises in distress (but not a sharp clack of the motor running into something).
Quote:
You say trial and error, so also I'm assuming that the sub bottoming out once or twice is not a problem, but constant bottoming out would eventually damage woofer?
Basically yes, with the exception that if you push it hard enough you can probably damage it on the first shot. Something like putting 4000W on a driver that should only get 250W might wreck a driver in one shot.
Stereodude is offline  
post #75 of 87 Old 11-24-2012, 05:46 PM - Thread Starter
Senior Member
 
Evolvo's Avatar
 
Join Date: Jan 2008
Location: West Michigan
Posts: 229
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
This may sound stupid but technically speaking could I play War of the Worlds at 100 watts with no HPF just to see how it sounds, or would this be a huge risk to the driver.

I previously had played "bass I love you" without the HPF on and I noticed the woofers was moving big time and the air was gushing out of the box, but I was scared to to turn it up. So technically in this situation was the woofer ok because the woofer wasn't making any bad sounds?

Also is it possible that the natural rolloff of a sub could act as a HPF considering most subs take a steep dive after the the tuning frequency anyway?
Evolvo is offline  
post #76 of 87 Old 11-24-2012, 05:51 PM - Thread Starter
Senior Member
 
Evolvo's Avatar
 
Join Date: Jan 2008
Location: West Michigan
Posts: 229
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
Quote:
Originally Posted by LTD02 View Post

"Is there a way to ultimately tell what your sub is tuned to, so that you can put the high pass filter at the correct frequency?"
without any gear, you can run some test tones and watch the cone motion. at tuning, the cone will move little. above and below it will be moving much more.

I just ran tones in 2 DB increments from 22hz down to 8hz. At 16hz I have the least amount of cone movement. The cone moves more at 18hz than it does at 14hz. So I'm not sure if that means I'm closer to 14hz than 18hz, but we'll just say I'm tuned to about 16hz.
Evolvo is offline  
post #77 of 87 Old 11-24-2012, 06:26 PM
AVS Addicted Member
 
LTD02's Avatar
 
Join Date: Oct 2003
Posts: 16,199
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 233 Post(s)
Liked: 947
"Also is it possible that the natural rolloff of a sub could act as a HPF considering most subs take a steep dive after the the tuning frequency anyway?"

no. below tuning the driver unloads from the sub and flops like it is in free air.

"we'll just say I'm tuned to about 16hz."

great.

Listen. It's All Good.
LTD02 is online now  
post #78 of 87 Old 11-24-2012, 06:38 PM - Thread Starter
Senior Member
 
Evolvo's Avatar
 
Join Date: Jan 2008
Location: West Michigan
Posts: 229
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
Quote:
Originally Posted by LTD02 View Post

"Also is it possible that the natural rolloff of a sub could act as a HPF considering most subs take a steep dive after the the tuning frequency anyway?"
no. below tuning the driver unloads from the sub and flops like it is in free air.
.

I don't know quite what that means but I'm going to take a stab. The box frequency is actually rolling off and not the amount of power that is being applied to the woofer below 16hz. So a HPF will send a week signal to the woofer so the woofer doesn't even attempt to create play loud below a certain frequency.
Evolvo is offline  
post #79 of 87 Old 12-04-2012, 05:52 PM
Advanced Member
 
AI Limited's Avatar
 
Join Date: May 2005
Location: CA
Posts: 690
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
Quote:
Originally Posted by Evolvo View Post

I don't know quite what that means but I'm going to take a stab. The box frequency is actually rolling off and not the amount of power that is being applied to the woofer below 16hz. So a HPF will send a week signal to the woofer so the woofer doesn't even attempt to create play loud below a certain frequency.

The amount of power is not rolling off below tuning. A high pass filter prevents the sub from playing frequencies below the frequency at which it's designed to work at, or more precisely, it attenuates the signal by 6db/octave or more (12db, 24db are also common "slopes"). The high pass filter attenuates the signal to the amplifier, which in turn doesn't send the power to the sub.

AI Limited
AI Limited is offline  
post #80 of 87 Old 12-04-2012, 06:21 PM
Senior Member
 
kcnitro07's Avatar
 
Join Date: Jul 2011
Posts: 302
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 13
Quote:
Originally Posted by AI Limited View Post

The amount of power is not rolling off below tuning. A high pass filter prevents the sub from playing frequencies below the frequency at which it's designed to work at, or more precisely, it attenuates the signal by 6db/octave or more (12db, 24db are also common "slopes"). The high pass filter attenuates the signal to the amplifier, which in turn doesn't send the power to the sub.
Meaning the power is redirected to a resistor somewhere and is output as heat nested of sound.....I think lol

kcnitro07 is offline  
post #81 of 87 Old 12-04-2012, 06:50 PM
Advanced Member
 
AI Limited's Avatar
 
Join Date: May 2005
Location: CA
Posts: 690
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
If it is a passive crossover, it is made of inductors and capacitors, 1 each for a 12 db/octave device, or just a cap for a high pass 6db/octave, or just an inductor for a 6db/octave low pass filter. In the digital domain, a dsp usually modifies the frequency response prior to amplification.

AI Limited
AI Limited is offline  
post #82 of 87 Old 12-09-2012, 02:05 PM - Thread Starter
Senior Member
 
Evolvo's Avatar
 
Join Date: Jan 2008
Location: West Michigan
Posts: 229
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
I never posted pics of the finished product and hate when people don't so here they are. I added another piece to the front baffle so the woofer could be inset. I also rounded the edges and ports to give sub a more finished look, added polyfill to enclosure walls and then slapped some paint on them. They sound and look fantastic tuned to somewhere around 16hz and no port chuffing. All I ever dreamed of, except I'd like one more for the back of the room.










Evolvo is offline  
post #83 of 87 Old 12-09-2012, 02:37 PM
AVS Special Member
 
brian6751's Avatar
 
Join Date: Mar 2006
Location: Canton, MI
Posts: 3,297
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 13 Post(s)
Liked: 101
Nice job! How do those Cornwalls sound up that high? How high up does that put the tweeter? I want to raise my cornscalas up more an not sure how high to go.

Xbox One Gamertag = The Barbeerian

PS4 PSNID = The-Barbeerian
brian6751 is offline  
post #84 of 87 Old 12-09-2012, 04:11 PM - Thread Starter
Senior Member
 
Evolvo's Avatar
 
Join Date: Jan 2008
Location: West Michigan
Posts: 229
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
Quote:
Originally Posted by brian6751 View Post

Nice job! How do those Cornwalls sound up that high? How high up does that put the tweeter? I want to raise my cornscalas up more an not sure how high to go.

I have tiered seating so the tweeter is ear level. They sound amazing. Bass is super tight and I get great soundstage. The stands are filled with 75lbs of sand. What are u going to replace Ur tht's with? Are u building Cornscallas? I really like the La Scala midrange better. 22" stands about and the tier is 14".
Evolvo is offline  
post #85 of 87 Old 12-09-2012, 04:35 PM
AVS Special Member
 
brian6751's Avatar
 
Join Date: Mar 2006
Location: Canton, MI
Posts: 3,297
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 13 Post(s)
Liked: 101
Quote:
Originally Posted by Evolvo View Post

I have tiered seating so the tweeter is ear level. They sound amazing. Bass is super tight and I get great soundstage. The stands are filled with 75lbs of sand. What are u going to replace Ur tht's with? Are u building Cornscallas? I really like the La Scala midrange better. 22" stands about and the tier is 14".

Not sure what I'm going to replace the tht's with. Have to sell them first. Something with the dayton or si 18".

I already have the cornscalas. They have 2" risers on them already but I'm going to make some concrete filled risers for them to sit on to get the tweet/mid up to ear level.

Xbox One Gamertag = The Barbeerian

PS4 PSNID = The-Barbeerian
brian6751 is offline  
post #86 of 87 Old 12-09-2012, 08:58 PM - Thread Starter
Senior Member
 
Evolvo's Avatar
 
Join Date: Jan 2008
Location: West Michigan
Posts: 229
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
Quote:
Originally Posted by brian6751 View Post

Not sure what I'm going to replace the tht's with. Have to sell them first. Something with the dayton or si 18".
I already have the cornscalas. They have 2" risers on them already but I'm going to make some concrete filled risers for them to sit on to get the tweet/mid up to ear level.

Did u build Ur cornscallas? Do u have a thread? How do they sound compared to Cornwall's?
Evolvo is offline  
post #87 of 87 Old 12-10-2012, 11:15 AM
AVS Special Member
 
brian6751's Avatar
 
Join Date: Mar 2006
Location: Canton, MI
Posts: 3,297
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 13 Post(s)
Liked: 101
Quote:
Originally Posted by Evolvo View Post

Did u build Ur cornscallas? Do u have a thread? How do they sound compared to Cornwall's?

yep. heres the thread

http://www.avsforum.com/t/1438540/cornscalas-2-way-tractrix#post_22645894

i never had cornwalls. i had La Scalas, but its just like they say, La Scala mids and highs with bass. They are monsters.

Xbox One Gamertag = The Barbeerian

PS4 PSNID = The-Barbeerian
brian6751 is offline  
Reply DIY Speakers and Subs

User Tag List

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page


Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off