PC Ultra bottoming out...

Jakakadave

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I'm afraid I'm rather a 'tard when it comes to the actual setup of my speaker system. Anyway, like many of you no doubt I like to watch DVD's at moderately ferocious volumes but the problem is, as soon as i get to a volume at which i feel i'm gettin the kind of bass I crave. I.e. i can feel it in my chest and my trousers are flapping occasionally, the sub bottoms out when it gets really deep leaving me frustrated and concerned about the health of my beloved PC Ultra.

I really want gut wobbling bass as often as possible - i love it so very dearly. What do i do?

The room is the living room of my open plan flat - the lounge is probably about 1000sq ft floor space, ceilings about 12ft.

One admission, the sub is only calibrated by ear (which i know isn't good enough, but work, being a bit thick and various other excuses have conspired against me)

Cheers guys
 
12000ft^3 is a very large space to fill with any sub. Assuming that your 'by ear' setup' isn't resulting in you sitting in a huge room induced null, there are only a few solutions:

- Run the sub in it's highest tune (20Hz) to maximise SPL capability - In a room that size, you're going to have to pick between extension or SPL. I would expect minimal room gain to prop up the bottom end, so the sub is going to have to hold it's own.

-Move the sub closer to the listening position. Closer=Louder.

-Buy more/bigger subs.

I really would recommend at least doing basic setup with an SPL meter and test tones to check what you're actually getting in room though. Until then, any suggestions (that may well turn out to be correct) could also suffer from exactly the same problem; the biggest sub in the world can't boost a null.;)

Incidentally the HTS6B, awsome though it is, is no more capable at the trouser flapping infrasonics than a single PB13. It might be huge, but it has to divide that volume by four, so it's bottom end is only comparable to that of four subwoofers 1/4 the size, each one of which is smaller than a PB13. It does however possess ridiculous capabilities at the kick in the chest frequencies which are a lot higher and easier to do. That's why so many night clubs feel impressive but if you stop and listen, they don't go that deep.:)

Russell
 
Have you run Audyssey on your 805? This will be a big step up over calibrating the sub by ear. This sounds to me like it could be caused by the subwoofer channel gain on the amp being too high and overloading the input. Audyssey will rectify this.
 
from the history of OP's posting i guess he owns old Ultra

All the subs I've had and I have never bottomed out one of them, and that's not to say I do not go loud because I do and most of the time, I would of thought he is running the settings extremely hot to do this :eek:
 
The room is the living room of my open plan flat - the lounge is probably about 1000sq ft floor space, ceilings about 12ft.
I say again, 12000 cu ft!

My room is 1750cu ft, AngelEyes' room is at least double that, so the OP's room is three to four times the volume of a really good size room. To put in perspective, a single garage conversion like UrbanT's would be a shade over 1000 cu ft.

What single sub would people expect to 'wobble' 12 single garages with exactly?

Russell
 
12000 cu ft!

My room is 1750cu ft, AngelEyes' room is at least double that, so the OP's room is three to four time s the volume of a really good size room. To put in perspective, a single garage conversion like UrbanT's would be a shade over 1000 cu ft.

What sub would people expect to 'wobble' 12 single garages with exactly?

Russell

He did say it was an open plan flat. Given the dimensions, I would guess something like a conversion of an old industrial building. I imagine it being like the loft conversions you see in films.
 
He did say it was an open plan flat. Given the dimensions, I would guess something like a conversion of an old industrial building. I imagine it being like the loft conversions you see in films.

If that is the case then he certainly needs a few more subs to fill his listening area.

Edit : I would say atleast 2 PB13 Ultras at the front, 2 at the sides and 2 more at the rears ! :eek: :devil:
 
That's the spirit!

If that doesn't work, he can always stack additional units until the required SPLs are met and/or the neighbours move out.:devil:

Russell

PS. I'm assuming the measurements to be accurate, but a chapel conversion or some such, would approach this sort of volume easily.
 
Hi Guys!

Yep, thats for the assistance. Well, yes it is the old Ultra 12 rather than that new fella - I was able to pick mine up from Badger as he was selling his and lived not far from my old house.

My flat is a big warehouse conversion - you can see my room in the image below. You can see about half of it in this picture. I think the real trouble is though, the lounge and kitchen are semi open plan so if you are in the kitchen and the sub is doing it's thing, the bass is really loud, but it's not as that noticeable when you are actually sitting there.

loungeca1.jpg


For it to be bottoming out, I'm talking about volumes of around -5 to 0db on the Onkyo 805. It's pretty loud, but you dont really get convincing rumble in your chest and trouser flapping below volumes like that.

BUT - if you get to something which has extreme bass, like for example the explosion at the start of children of men - it bottoms out.

Also, watching death proof, which is AWESOME, there is a really nice bit of bass as Kurt Russels car's V8 thunders past, but when he crashes it, it's all undermined by the dreaded pop of it bottoming out.

I have just one port bung in... is my gain set too high maybe?

Incidentally - i know my rears aren't in the ideal position, but otherwise they really get in peoples way as they walk around the flat. I'd deal with it personally. but others arent so accomodating.
 
That's a huge room... put into perspective by how tiny the pool table looks!!!
 
When you say that your rears get in peoples way is this flat yours or yours and your partners or a shared apartment by a few other people..........if its just your then ask in a nice way to not touch them and walk carefully around them etc etc.:mad::D

You can buy movable bespoke large partitions and even tracks which you can lay in which ever shape it needs to be........they would be setup and close off the room to what ever size you choose so when closed all your equipment should be setup and calibrated to the room size you have chosen..........then when the friends come around and parties held can be pushed back to one or both ends of the walls opening up your vast lol space again.

They also come in various colours and finishes and even plain so you can paint them yourself.

P.S........Fanstastic place though with plenty of scope!
 
You're listening at those levels in a flat? Don't you have any neighbours to worry about? :eek:
 
I have just one port bung in... is my gain set too high maybe?

Really nice flat.

I'm interested in the gain setting from the Onkyo to the sub? I have a feeling it may be set too high and overloading the line level input.
 
I think the real trouble is though, the lounge and kitchen are semi open plan so if you are in the kitchen and the sub is doing it's thing, the bass is really loud, but it's not as that noticeable when you are actually sitting there.

I'm surprised no-one has picked up on this line.
If, as you seem to suggest, the bass is loud in the kitchen, but not when you're sat down watching the telly, it does indeed suggest you're sitting in a null and as Russ said, you're not going to improve that.

You need to move the sub around to as many positions as you can and run some test tones to see what's happening.
I expect you're just expecting too much of it and the gain needs to be turned down a touch.
 

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