1. Join Now

    AVForums.com uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

A whole bunch of sub questions for the experts

Discussion in 'Subwoofers' started by Dom H, Oct 4, 2002.

  1. Dom H

    Dom H
    Guest

    Products Owned:
    0
    Products Wanted:
    0
    Ratings:
    +0
    Ok here goes (before I start shut it skippy!)


    I'm sure everyone knows my choice of breadbin/midwoofer/shoebox whatever you want to call it and I'm sure everyone has seen my spl results. At the moment the sub is setup in a 12' * 13' ish room.


    1. If (or rather when) I move my setup into a larger room (say 20'sq max) what will happen to my sub's freq curve in terms of bass extension and output.

    2. What will happen if I add more (1 or 2) pro50's in terms of extension and output?

    3. Seeing as the system is used 50/50 music/film, for music what is the general consensus regarding sub size, do larger subs sound slower(wrong word i know eric). Would mulltiple small subs give a tighter sound?



    Thanks

    Dom.
     
  2. Jase

    Jase
    Well-known Member

    Joined:
    Mar 16, 2001
    Messages:
    9,532
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    136
    Location:
    UK
    Ratings:
    +932
    I´ll put my flameproof suit on for this one!;)

    1. It will change, each room will give a different reading and will vary with different subs.

    2. If you add more, you should get increased output and extension, though I´m not sure by what factor. i.e two subs won´t give you twice the output. Feel free to correct me on that someone!

    3. Depends on the sub and not the size I would say, my Velodyne CHT 15 is better than my old Rel Q200 and that was a small 10 inch job. The Velodyne sounds much better (tighter, faster call it what you will).

    Hopefully we´ll get some comments from the experts.:)
     
  3. Lowrider

    Lowrider
    Guest

    Products Owned:
    0
    Products Wanted:
    0
    Ratings:
    +0
    My expertize is that I managed to setup my subs right, IMHO... ;)

    1 - Too many variables, size, materials, furniture...

    2 - You also get a better spread bass, less cancelations...

    3 - Because of point 2 you will better off with two smaller subs, as long as they have similar quality... nothing to do with size, but closed subs will integrate easier than ported...
     
  4. Dom H

    Dom H
    Guest

    Products Owned:
    0
    Products Wanted:
    0
    Ratings:
    +0
    would I be right in saying

    1. Output would be reduced (i.e across the whole freq range), extension would remain the same (i.e would stay -3dB @ 20Hz or whatever)
     
  5. Lowrider

    Lowrider
    Guest

    Products Owned:
    0
    Products Wanted:
    0
    Ratings:
    +0
    I don´t think you can say anything, depends on too many factors, but everything else equal you could say that you will ear less bass...
     
  6. Dom H

    Dom H
    Guest

    Products Owned:
    0
    Products Wanted:
    0
    Ratings:
    +0
    Eric, nic, tom care to add anything?
     
  7. Nic Rhodes

    Nic Rhodes
    Well-known Member

    Joined:
    Mar 23, 2001
    Messages:
    17,133
    Products Owned:
    0
    Products Wanted:
    1
    Trophy Points:
    133
    Location:
    Cumbria
    Ratings:
    +1,277
    Boris is the real sub meister around here but I am sure someone will add something. Off to have a think myself:D
     
  8. Phil Hinton

    Phil Hinton
    Editor Staff Member

    Joined:
    Jan 18, 2001
    Messages:
    9,787
    Products Owned:
    3
    Products Wanted:
    0
    Trophy Points:
    166
    Location:
    AVForums
    Ratings:
    +7,190
    Who's Boris? I have never heard of him or seen any posts from him.

    Dom,

    While The Mj is a fine small Sub, It will definately struggle to load a larger room with any real lower freq at substansial Db's.

    It also depends a lot on the room layout (which I have discovered) and furnishings. I had two Rel Storms in a 13.5ftx14ft Dedicated room, and while they loaded the room well, they tended to cancel each other out at certain freq's. Sub instals are all about experimentation and actual listening sessions, and very little to do with graphs. I always take anything on paper with a pinch of salt, it's what it actually sounds like that counts(althougha little research with an spl with give a very rough idea of nodes etc in the room).

    Since taking delivery of My Velodyne, I am grinning very wide indeed, and the previous problems seem to have gone. This is a different beast to the Rels altogether, and the extra power and low distorsion servo, help no end to loading the room with quality bottom end.

    Experiment a little with positioning and listening tests(always use the same material), but I have heard the MJA, and i doubt you will get a good output in a room the size you mention. Might be an idea to look at some more powerful products.
     
  9. Dom H

    Dom H
    Guest

    Products Owned:
    0
    Products Wanted:
    0
    Ratings:
    +0
    While the Pro50 does a great job in my 12' sq room in both extension and output I agree in a bigger room (thinking about it, not likely to be bigger than 15ft sq) it is definitely going to struggle. I'm talking no louder than about 5dB shy of reference listening level.

    The thing is I have yet to hear a better sub musically and for this reason I wanted to hang on to it, the plan was to add more Pro50's to maintain the same level in the larger room, keeping the musical abilities intact.

    For example wouldn't 3, maybe even 4 pro50's boost the level (with plenty of headroom) to an acceptable level in a larger room?

    Don't 15/18's sound a little 'slow' musically? (all my experience is with car audio so HT may be different)


    So I spose my question could be rewritten;

    Multiple Pro50's as musical as 1 AND enough extension/output for movies in a moderate sized room?


    Many thanks

    Dom.
     
  10. Nic Rhodes

    Nic Rhodes
    Well-known Member

    Joined:
    Mar 23, 2001
    Messages:
    17,133
    Products Owned:
    0
    Products Wanted:
    1
    Trophy Points:
    133
    Location:
    Cumbria
    Ratings:
    +1,277
    Dom

    Here is my take on things for what it is worth.

    1 There are just too many variables on this one to predict what happens. This is a suck it and see. A move away from a square room will be very beneficial however.

    2 more than one sub can lead to a better balance of bass around the room. It might allow you to flatten out gross peaks and troughs in the bass output. 2 subs are generally much better than one, however there are always exceptions. You probably won’t notice much additional extension. This is not dual subs are about. You will get better quality of bass (smoother in room response) and a ‘load’ will have been taken off the sub. Two subs stacked will give you 6dB addition capability, two non stacked will give 3dB, in reality somewhere in the middle is what you are likely to achieve. This means that at the same sound level each sub is working much less hard, therefore distortion is lower, and things sound better as well as having flatter in room response. Small subs like pro50 can be working at their limit so any help on the distortion front is helpful.

    3 larger subs don’t sound slower per se. It is a myth put about by idiots and suppliers of small subs. There is no such thing as slow bass (does the speed of sound change according to small changes in frequency?). You obviously have seen the posts on this by Nic, Eric and Boris I think but this ‘tightness’ thing may be tied up with amps not man enough to control drive units and the corresponding high distortion. Distortion ladened bass can sound ‘ponderous’ and is often mistaken for ‘slow’. It isn’t but it ain’t tight and it is full of distortion. Low notes are the ones which suffer from large distortion most so I think this is why people notice it more with bigger subs and think big subs means slow. Pop on your servo sub and all this disappears even big ones. It is not completely down to size however but also how you do it. There are many horrible large subs but also some good small ones as well. This is why Paradigm Servos and some Velodynes are popular here now, people have seen the light (and SVS / HQ DIY brigade (delete appropriately!)).

    Boris posts under Ramius name here, he certainly has the best knowledge of the bass meisters who are regulars here. Excellent links as well. I always enjoy his words of wisdom and common sense.
     
  11. uncle eric

    uncle eric
    Guest

    Products Owned:
    0
    Products Wanted:
    0
    Ratings:
    +0
    JUst a brief word (sorry, very busy today) about the use of multiple subs here. While the results can indeed be superior in many ways from single subs, it is generally more difficult to get right (as THX Phil found out)
    A number of problems can arise, the worst and most common being cancellation. Again, I'm generalising, subs should be at an equal distance to the listener. This is why you sometimes see stacked subs, ie one on top of the other, as its the easiest way to ensure equal distance.

    From the bass apprentice;)
     
  12. buns

    buns
    Banned

    Joined:
    Apr 29, 2001
    Messages:
    6,066
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    58
    Location:
    Belfast
    Ratings:
    +1
    i have little sub experience, but here is what i have found.

    My normal setup has a single storm......it happens to be behind one of my sofa's and, when on that sofa, the result is highly satisfactory. However, on the other sofa, the result is somewhat less so as is the case in various parts of the room. On dem i tried a 2nd one in the opposite part of the room......i had expected a massive difference, but in reality the improvement was that the bass was just more even throughout the room (of course there was a bit more bass, but it wasnt anything like what i had expected.

    That said, on the deaper notes the 2nd sub did help a fair bit and as beekeeper said, it was obvious that the subs were straining less and the quality of the note was better.

    Ad
     
  13. Dom H

    Dom H
    Guest

    Products Owned:
    0
    Products Wanted:
    0
    Ratings:
    +0
    Cheers guys, much apreciated.

    Ok then lets say for arguments sake in my current room (aprox 12ft 'not' square) my pro50 goes low enough and has enough output (ignoring distortion levles) for the levels I listen at (pretty loud usually -5dB)

    What I'm hoping for is when I put my current pro50 in the larger room the extension stays the same but the output drops so I can then add more pro50's raising the output back to acceptable levels (with some overhead) and keep the musical sound of the pro50 I like so much. I'm thinking 4 pro 50's stacked in a 2by2 cube (might be the size of a normal sub then :p)

    I have always used 1 system for music/HT, both must be taking into consideration when purchasing.


    Dom.
     
  14. Guest

    Products Owned:
    0
    Products Wanted:
    0
    Ratings:
    +0
    Dom.

    I think Nic Rhodes summed it up in a previous thread sometime back....

    Until you've heard / felt REAL sub-bass, you begin to realise what you've been missing out on...

    I've learned shyte loads about bass from the 'low-end dwellers'

    (Eric, Nic, Boris et al)

    It was down to some of these scoundrels that i purchased the
    Velodyne HGS-18...
    I previously owned M&K & REL units.

    The HGS-18 is one of those pieces of equipment that just makes you excited about watching films / listening to music again.

    I love it to bits.

    Adzman
     
  15. Phil Hinton

    Phil Hinton
    Editor Staff Member

    Joined:
    Jan 18, 2001
    Messages:
    9,787
    Products Owned:
    3
    Products Wanted:
    0
    Trophy Points:
    166
    Location:
    AVForums
    Ratings:
    +7,190
    Ah yes, I now know who you mean.

    Dom,

    You said The mja was the best at the price, just out of interest did you look at/consider the CHT10 from Velodyne? This is three times the sub that the MJA is? Just a thought.
     
  16. Dom H

    Dom H
    Guest

    Products Owned:
    0
    Products Wanted:
    0
    Ratings:
    +0
    Wouldn't really fit.

    It's not really a problem if when I move to a bigger room I replace the pro50, but I sorta want to hang on to it if just for music alone. I can't help but think a big 18 which will be great for HT won't be as musical as the sub i have at the mo. Surely the bigger the sub the more inertia therefore change in velocity will be slower.
     
  17. Guest

    Products Owned:
    0
    Products Wanted:
    0
    Ratings:
    +0
    Dom...

    Use search option for these words.

    'Rel sub-terfuge'

    It's got some excellent stuff in it by all the low-end dwellers.

    In it, comes the following from Nic Rhodes (cheers Nic)

    Sorry if the previous answer was short. Standard 15 /18 inch units can sound slow, that is why the car people use 10 inches. The answer to this is an active servo feedback sensing control. It is a very sophisticated and efficient for subs. This is why it is in a different league to other contol mechanism (and prices) with a notable exception.

    Check that thread out for some great reading.

    Adzman
     
  18. Phil Hinton

    Phil Hinton
    Editor Staff Member

    Joined:
    Jan 18, 2001
    Messages:
    9,787
    Products Owned:
    3
    Products Wanted:
    0
    Trophy Points:
    166
    Location:
    AVForums
    Ratings:
    +7,190
    If it makes you feel better, I got rid of Two Rel Storms, noted for its musicality, for the CHT15.
    As I am upgrading my system at the moment I can only use it with cds at the moment, and let me tell you this is one brilliant musical sub, that adds more than the Rels ever did in my particular room. And as far as I (and others) are concerned there is no such thing as a Slow sub, a highly distorted one yes which gets mistaken for slowness, But not slow. And there is certainly nothing slow about servo technology.

    And why Wouldn't it fit ?
     

Share This Page

Loading...