First Impressions, EBS Shiva Sonosub... (1 Viewer)

[Tommy T]

First off let me say that Kyle was right when he said I would be addicted. Before I even finished this project, I was planning the next.

Now to the good stuff. I started my Shiva Sonosub about 2 weeks ago and all I can say is this thing is sexy. A term normally reserved for my wife, I'm loaning it to my sub. I didn't think I could create something this nice with my own hands. The Mahogany stain on the birch it just so purty!

A little background. My wife and I purchased our first home a little over 2 months ago and my Sony sub just couldn't cut it. After spending countless hours on this site, I just knew I had to have my own sub. I was contemplating a SVS but since I have a new house and no tools, I thought I could use the sub as justification to buy some. About $200 later I had tools. Home Depot for supplies and Acoustic Visions for Shiva, 300-793 PE Remote Amp, and 4" Flared Port and I was on my way.

Finished it Friday and wanted to give it a full 24 hours for the caulk and glue to dry so yesterday was the day.
I anxiously sat my happy butt on the couch, calibrated to 75db, with the sub a wee bit hot at 78 and started off with Monsters' Inc., when Boo cries. Good Lord, Oh My God! I could have sworn my house was coming down! Wife and dog head for the hills, she's about to blow!

Now, wanting more, I pop in Fight Club, Psycho Boy scene, and crank up the volume a bit. Oh, ooh. Problem. My sub just starts fluttering, bottoming, I dunno. Amp is dialed in at only 1/4 way, receiver set to -3. This can't be right. This puppy has to have more juice, right? What could be causing this?

Slightly distraught, I pop in SW:TPM, pod race, same thing at a higher volume. I back it down a bit and it's fine. I'm not even using the amp's potential so I'm hoping this is an easy fix. I'm open to any and all suggestions as I've probably sank close to $600 into this sub and I KNOW this can't be it.

Sorry for the length but I know you guys can help me out.
Thanks to Patrick and Warren and Dustin for creating the web pages that served as my template. Because without you guys, I probably would have never realized the joy of DIY.

 

[Jack Gilvey]

Congrats, the Shiva EBS is a great, great alignment!

Amp is dialed in at only 1/4 way, receiver set to -3. This can't be right. This puppy has to have more juice, right? What could be causing this...I'm not even using the amp's potential so I'm hoping this is an easy fix.

The setting of the volume control on the amp or the dB level on the receiver's sub-out do not indicate how much wattage the amp is actually producing. It doesn't sound like amp clipping is the problem, anyway.

 

[Tommy T]

Jack,
Yes, it is distorting at reference. Actual room dimensions are about 20' front to back by 25' side to side. This opens to the kitchen which adds another 15' by 25'. I'm only concerned because while the Shiva seems to be effortless, I could tell the Sony was distorting. It just seems that the Shiva isn't breaking a sweat and starts popping way before it should. I could be wrong. I understand that the setting of the amp is only the gain but I had to drop both of these drastically from the settings I had on the Sony. I initially had my amp gain set to 3/4 but even then it was way off the meter with the receiver set to -10.
Am I expecting to much? Will a break-in period help? As previously stated, I'm open to any and all suggestions.

 

[Geoff L]

Yes, great feeling when doing your own DIY project!!!

What is the Subs supposed tuneing point?
The PE sub amp, is boost free correct?

More than likley your just asking to much from the 12-incher. Thats allot of space to fill with the last octave...

Regards
Geoff

 

[Tommy T]

Following the plans, the EBS alignment is tuned to 18.1Hz. You are correct, the Amp, is boost free.
Would a rumble filter take care of the popping if I set it to 17Hz?

 

[Dustin B]

Set the receivers sub level to a middle value. Then using the SPL meter set the gain. Don't worry if it ends up down around 1/3rd or less (the PE amps are known to have very high gain, so everybody ends up setting the gain dial very low; I'm at less than 1/3 on mine). Like Jack said, the dial position has no relation to how much power the amp is putting out. If the input signal is high enough you can clip the amp with the gain backed all the way off.

Then like Geoff said. If you are calibrating to full reference level and trying to play at this level you are asking for too much in that size of a room. If you want full reference in that room I suggest a 480L dual Tempest tuned to 16hz with twin 6" ports and two 300W amp channels.

If there is no rumble filter in place, adding one that starts at 17-19hz will definately help. But at reference I don't think it will take care of bottoming problems.

 

[Geoff L]

I've never used the Remote Amp and don't know if anything is different or not than the PE 300-794.
Jack, Pat and Kyle would likely know about the corner filter and slope as I belive they all have used this amp. I dare not assume that it's the same design as the un-boosted 300-794.
Might be, might not.
A steep subsonic filter would add some protection but belive it won't stop the bottoming at referance in the last octave. Assuming no protection now in the amp.... Dialing back the volume is the only cure for that. :frowning:
Or more Woofage which means more DIY. You could close off the room to the kitchen, but surley this isn't an option obviously.
Have you run a freq disc and spl meter to see what is happing in your room with peeks a valleys and at what freqs. Placement and EQ-ing might get you a "little" more out put.
Are you in a corner now with the sub?
This will get you max room gain to start, maybe not the best freq response, but most "free" room gain.
I'll let the HTF Pro builders help you, as I am reletivly new to the game of DIY myself!
Regards
Geoff
Follow Dustin advise on setting the amp gain....He's posting as I am right now...

 

[Tommy T]

Yep, it's in a corner. Haven't run a frequency sweep, but will. What should I be looking for when I run this?

Dustin, my wife was surprised that this one turned out so well, but if I suggested a 480L anything, I'd be living in it! Maybe I can get away with another 142L Shiva, if I'm lucky.

BTW, just curious. How can I tell if there are any leaks in my set-up? Since I have the amp and remote flush mounted, I am curious to see if I'm sealed up around the edges. I thought about taking a lighter to the edge when playing but I'll be damned if I set my baby on fire!

Thanks guys for the advise though. I'm going to check and see what I can do, but listening at less than reference, that's going to be the hard part!

 

[Dustin B]

Thanks guys for the advise though. I'm going to check and see what I can do, but listening at less than reference, that's going to be the hard part!

What's the rest of your system? I'm usually perfectly happy with the level at 10dB below reference with the sub slightly hot. I don't even give demos at full reference (usually 5dB below reference). At my demo level I've recorded 117dB uncorrected off my rat shack meter when the ball explodes in the THX into to TPM. At full reference I can't stay in the room. And with LOTR I can't even stay in the room at 10dB below reference (that sound track is recorded sooo loud). Granted my room is relatively small and my amp isn't up to driving my speakers cleanly at that level :p)

For leaks a kleenex can work well. Hold it up to the suspect seams while the sub is pounding away and any leaks should be quite appearant. If you do have one, sealing could help your problem somewhat.

A second EBS Shiva would definately help your problem. Not sure if you could do full reference even with two, but you should be able to come very close. As properly coupled a second identical sub will gain you 6dB of clean headroom across the board.

 

[Tommy T]

Dustin, good point as that was going to be my next series of questions. I'm running this off the Sony 540HTiB. It was fine in my apartment but in the new home, it just wasn't cutting it. I'm planning on upgrading the 27" Sony next to a 50-65" HDTV. I'm lost as to all the options there but I'll save that for another week or so.

I just felt that maybe I had done something wrong and that there would be a quick fix or something I overlooked. I'm not home right now but I'll be running down all of the items mentioned above when I get there.

I dared not even try LOTR yesterday! It ate my Sony up to pieces and I just couldn't handle another disappointment so I'm going to try everything before I pop that one in tonight.

Another question that just struck me in regards to reference. When I calibrate with a disk vs when I'm watching a movie, I get 2 different volume levels for 75db. For example, I calibrate to 75db using disk and volume is set to -20. When playing movies at -20, I easily hit peaks over 100db. Is reference then, the volume level on my dial where the disk calibrates 75db, or when I'm watching a movie, when I have 75db peaks? Man I hope that made sense cuz I do not want to type it again!

Thanks,

 

[Tommy T]

OK, just posted some pics of the building process. This is my very first attempt and building a site so take it easy on me!
Here's the link to get to the page I just created.

 

[Dustin B]

Take it easy on you. You kidding, that looks great. Any chance you could post some larger pictures of the finished sub?
Give this a look to learn more about reference level:
http://www.hometheaterforum.com/htfo...985#post993985
What disc are you using for calibration?
A Sony HTIB at full reference level Don't mean to be rude, condescending or mean. But I don't think I could take a Sony HTIB at 15dB below reference in a medium sized room little lone full reference level in a larger room. I'm amazed you can play it that loud without blowing something.
Now that you are into DIY, definately look into build some new speakers too. Do some looking around here for the numerous options avialable. Upgrading the receiver when you do this would be a good idea too.

 

[Geoff L]

Darn, went to your link and the first 6 pictures load, and thats it. The text dose show and a box for the picture also including your links I can see, but NO pick in the box!!!!
Uggg

Anyone else having a problem seeing all the pic's????

I'm on Web-tv so maybe thats got something to do with it.

The 6 pictures I can see look great, but darn want to see the rest as it appears very nice with what I can see.

Really want to see your finished product!!!

Geoff

 

[Tommy T]

Thanks Dustin. I'll try to get some larger pics on there. I just wanted to put something out there so everyone knew what I was talking about.

Hey, no offense taken on the HTiB! I hadn't found HTF last year and my ignorance has been bliss! I just can't see buying speakers when building them is so fun! After the TV in about a month or so, I'm tackling the speakers and receiver next.

 

[Tommy T]

Guess I'm getting some traffic on the site because even I can't get in! A buddy of mine had no problem loading the page so I'm at a loss.

On the subject, are there any other Free web hosting sites that would allow for better file transfer?

 

[Tommy T]

OK! Thanks to Dustin for sharing some webspace, you can go here to see some of the larger pics.
I'll take some more pictures tonight and get them up on the site.

 

[Geoff L]

Tommy
I got in finally! Very nice!!!!
Did you do all that cutting without a router???
If so, very impressive hand control! The flush mount of the amp and remote eye is the only way to go for beauty IMO. Just don't like the look of a amp box attached to the out side of a tube.
Again very sharp looking sub buddy and your first DIY attempt, WOW...
Regards
Geoff

 

[Tommy T]

Thanks Geoff! Yep, just my trusty jigsaw, no router. A router would have made it easier and maybe faster, but I just took my time and went really slow!

 

[Dan Hine]

Nice job Tommy! That sub looks really sharp. I've gotta agree with Geoff, nice hand control with the jigsaw.

 

[Cam S]

Tommy, that is a FINE looking sub!! I REALY like the look that the Mahogany stain adds to the sub, just awsome.