joz Posted March 6, 2007 Share Posted March 6, 2007 Joz's 18"ers -------------------------------------------------------------------------------- After visiting some audio friends of late(you know who you are ) I have come to the realisation that deep bass is goooood! and the fact that although I have a capable sub it could be much better. Anyway over the last few weeks i've been listening to very impressive subs,both Infinate baffle and boxed. Another very good freind of mine(JA) seems to be a never ending source of hi-fi technical knowledge and is always suggesting the DIY thing to me.He has forever sung the praise of JBL subwoofer drivers,along the way he has worn me down and pointed out a pair of boxed JBL 2245 18" drivers on E-bay.They are in a box like those ugly un waf freindly stage type boxes with the fuzzy externals. Anyway I kept an eye on them placed one bid out of two total bids and I won them Origainaly I had contacted Andrew(Aslan)if i could get them to him but now the drivers are being freighted home only.Thanks anyway Andrew for offering mucho appreciated. Then they arrived!! Shyza!!they're damm big! Link to JBL 2245 Each cabinet is to have a volume of between 250-300 ltres. So I'm looking at a cabinet with the demensions of, H:600mm. W:1000mm. D:500mm. So two cabinets like this side by side to run as dual/stereo subs. With the height I'm wanting to acheive I was planning a sort of bench top scenario,this way they would look more like a low line cabinet fronted with grill cloth rather than additional large boxes,and I like the little feet AJW has under his Australs(very nice). Dilemma 1. At this stage I'm not sure which way to go with regards to power supplies? Do I go the way of plate amps or separate power amps with an external crossover?My issues are that I want the best possible intergration and don't know what will offer me whats best?.At the moment I still have two free channels on my Elektra amp,this may do for a while. With regards to plate amps,Jaycar is running a special at the moment.Their 350 watt into 4ohm amp I can get for $235 at the moment(its rated 240 watts@ 8 ohms)The speaker is an 8ohm and @95db sensitivity. The thought of having it simple and fuss free is appealing,hence the plate amps. Also not sure about the 6db boost at 35hz? Any suggestion really appreciated here Dilemma 2. The finish? They need to look non industrial because they are in my lounge. May go plain black,then get a nice top with side panels sprayed in two pac? This way it would look like one peice of furniture,Happy wife . Or good ol Bubinga(ala Osbourne) Dilemma 3. The thought of three of these muthas across the front is oh soooo tempting.All in an LCR configuration. I wonder when it will become to much?. This means finding a third driver,though JA said if a pair do come up he wants another aswell(he's truly nuts) I'm not really after the loudest subs around,but that extra headroom sounds nice. The drivers are now at Speaker bits,one being re-fitted with a new roll surround and the other being matched up as it had the wrong re-cone kit fitted While at speaker bits one of the guys there was really helpful and within minutes had BassBox6 up on the puter,modelling what could be done with theses drivers.Needless to say it seems they will do big SPLs and go quite deep.. So stay tuned with the adventures of my 18"of pleasure __________________ Link to comment Share on other sites More sharing options...
Grumpy Posted March 6, 2007 Share Posted March 6, 2007 If you go with the Jaycar amp plates you also get remote control. If I was building again I would go with the seperate amps and Xovers suggested by, I think, Seano at AVL? Can't wait for the progress pics. Speaking of the Jaycar amps, I use one and that boost at 35HZ has me scratching my head, but I might start a new thread about that later. Link to comment Share on other sites More sharing options...
Phil G Posted March 6, 2007 Share Posted March 6, 2007 Cool Joz, congrats on the new adventure. I'm sure with JA helping in the background you will not go wrong. That deep bass that some of the PA ground breakers have is very addictive isnt it? Looking forward to progress reports and pictures. Link to comment Share on other sites More sharing options...
Guest alebonau Posted March 6, 2007 Share Posted March 6, 2007 holy cow ! joz is about all I can say ! have you considered getting the boxes leather covered ? same colour as your couches and would blend in well in the room I think - presuming this is going ot be a low slung ? bench/ottoman like think that goes across the front below the pj screen. you could have the drivers even down firing to hide them visually. jsut thinkign of your current modern minimilist setup you have present. Still going to be big boxes I imagine so not sure how much hidign you can do of the boxes them selves ! wouldnt be suprised if the couple of channels spare on the elktra si plenty. they look like high efficiency drivers with a sensitivity of 95db and know ken ran his two ib 18" no probs of the elektra at one time. you could do this for starters anyways till fully explore other amp options via sgr and others. Link to comment Share on other sites More sharing options...
JA Posted March 6, 2007 Share Posted March 6, 2007 Also not sure about the 6db boost at 35hz? Any suggestion really appreciated here :blush: [/b] Joz, Good pick-up. The eq for these: 6dB is OK, but it needs to be at 20-25 Hz for best extension. You could use a parametric EQ for this. Best JA Link to comment Share on other sites More sharing options...
joz Posted March 6, 2007 Author Share Posted March 6, 2007 Joz, Good pick-up. The eq for these: 6dB is OK, but it needs to be at 20-25 Hz for best extension. You could use a parametric EQ for this. Best JA [/b] OK JA,please explain how this paralletic :biggrin: EQ works.In a language that even I can understand Link to comment Share on other sites More sharing options...
Keith_W Posted March 6, 2007 Share Posted March 6, 2007 Wow joz! Congrats on the purchase ... but that was the easy part I'm sure that ajw can make a cabinet for you, but I believe you can get someone in Melbourne to do it as well. Why not try SGR ... they can probably supply a plate amp of their own design. They also do a beautiful automotive grade finish, but (in my very humble opinion) a big sub in an automotive grade finish in a living room is a bit too much. This is why ... have you considered getting the boxes leather covered ? same colour as your couches and would blend in well in the room I think - presuming this is going ot be a low slung ? bench/ottoman like think that goes across the front below the pj screen. [/b] ... I think that Alebonau is a man of taste Great suggestion! Certainly will go a long way to diminish the size of that thing. Link to comment Share on other sites More sharing options...
JA Posted March 6, 2007 Share Posted March 6, 2007 holy cow ! joz is about all I can say ! have you considered getting the boxes leather covered ? same colour as your couches and would blend in well in the room I think - presuming this is going ot be a low slung ? bench/ottoman like think that goes across the front below the pj screen. you could have the drivers even down firing to hide them visually. jsut thinkign of your current modern minimilist setup you have present. Still going to be big boxes I imagine so not sure how much hidign you can do of the boxes them selves ! wouldnt be suprised if the couple of channels spare on the elktra si plenty. they look like high efficiency drivers with a sensitivity of 95db and know ken ran his two ib 18" no probs of the elektra at one time. you could do this for starters anyways till fully explore other amp options via sgr and others. [/b] Al, I prefer not to go for down/upfiring subs because... Most subs have very compliant suspensions and heavy cones for best low freq response. Putting them into a downfiring and upfiring is not ideal for the suspension as it can take on a permannet set in one direction and usually is not recommended. Infact it is even a good idea for a vertically mounted driver, particularly for very compliant suspensions, to rotate the driver in the baffle every so often/few years to even up any sag in the suspension? OK even when mounted in the vertical plane the suspension will be subject to the dead load of the cone, but the stiffness in the vertical direction will be considerably greater than the stiffness (compliance) in the direction of motion and less deflection will therefore result . Best JA Link to comment Share on other sites More sharing options...
Guest alebonau Posted March 6, 2007 Share Posted March 6, 2007 understand ja was jsut a suggestion to hide the big suckers. although would agree in much you say I did read an article from colin whatmough in the local aussie rags a few years ago on reasons why he didnt believe in cone sag. only his opinion and not to say though that in engineerin terms what you say doesnt make perfect sense Link to comment Share on other sites More sharing options...
JA Posted March 6, 2007 Share Posted March 6, 2007 OK JA,please explain how this paralletic :biggrin: EQ works.In a language that even I can understand [/b] Its just a normal eq that has had a few. :biggrin: :biggrin: It provides eq which is variable in frequency, amount (gain) and shape (Q). Even for the same frequency and the same boost you can have a sharp spike in the response (high Q) or gentle bump in the response (low Q) This is not possible on a normal (graphic) equaliser it has a fixed Q, usually around 1 or 2. Best JA Link to comment Share on other sites More sharing options...
joz Posted March 6, 2007 Author Share Posted March 6, 2007 Grumps thanks for reminding me of the links.I just went and had a look. Behringer Power Amp Behringer Crossover These are food for thought,thanks again Link to comment Share on other sites More sharing options...
JA Posted March 6, 2007 Share Posted March 6, 2007 Grumps thanks for reminding me of the links.I just went and had a look. Behringer Power Amp Behringer Crossover These are food for thought,thanks again [/b] And this digital crossover (which includes parametric eqs.- bands???) http://www.behringer.com/DCX2496/index.cfm?lang=ENG Spearmint uses one of these. Best JA Link to comment Share on other sites More sharing options...
Drizt Posted March 6, 2007 Share Posted March 6, 2007 Check out this bad boy power amp.. Crown XTi 4000 on ebay <h1 id="productTitle">Crown XTi4000 Power Amplifier (3200 Watts)</h1> Integrated proprietary DSP. Accurate, uncolored sound. Advanced protection circuitry. Switch-mode universal power supply. Link to comment Share on other sites More sharing options...
davidsss Posted March 6, 2007 Share Posted March 6, 2007 18" JBL subs, all I can say is wow. They should make the house shake quite nicely. DS Link to comment Share on other sites More sharing options...
Tony M Posted March 6, 2007 Share Posted March 6, 2007 holy cow ! joz is about all I can say ! have you considered getting the boxes leather covered ? same colour as your couches and would blend in well in the room I think - presuming this is going ot be a low slung ? bench/ottoman like think that goes across the front below the pj screen. you could have the drivers even down firing to hide them visually. jsut thinkign of your current modern minimilist setup you have present. Still going to be big boxes I imagine so not sure how much hidign you can do of the boxes them selves ! wouldnt be suprised if the couple of channels spare on the elktra si plenty. they look like high efficiency drivers with a sensitivity of 95db and know ken ran his two ib 18" no probs of the elektra at one time. you could do this for starters anyways till fully explore other amp options via sgr and others. [/b] Absolutely brilliant idea, Al.....gives me a few ideas, thanks Link to comment Share on other sites More sharing options...
terry j Posted March 6, 2007 Share Posted March 6, 2007 Hi JA and Joz welcome to the real world Joz!! Me thinks you will notice a difference!! JA, that piece of behringer kit would not be the one to use in this situation. Head on over to home theatre shack and check it all out over there. Link to comment Share on other sites More sharing options...
JA Posted March 6, 2007 Share Posted March 6, 2007 Hi JA and Joz welcome to the real world Joz!! Me thinks you will notice a difference!! JA, that piece of behringer kit would not be the one to use in this situation. Head on over to home theatre shack and check it all out over there. [/b] Why not- digitalis? Best JA Link to comment Share on other sites More sharing options...
terry j Posted March 6, 2007 Share Posted March 6, 2007 hi ja the dcx 2496 is a loudspeaker management system, lets you run a PA system etc, or as I have done here, run a two or three way active setup. It is good value, and as a bonus has (limited) PEQ capabilities. If you simply want to EQ your bass, there is a cheaper option, and more closely targetable for the job and that is to use the BFD's from Behringer, or maybe there is only one. Off the top of my head I can't give you the code number, but search on BFD and you should find it. A higher quality option, and more expensive, is the DEQ 2496 ( which spearmint has posted a thread on ) which is very good value in my book. It will even eq your main system once you know how ( the manuals really suck!). In any case, go to the shack and research it all there, it was the reason (using the BFD to eq your bass) that the whole site was founded. Plenty of the guys on this forum can help once you get into specifics but truly, it is the place to go for this type of thing. Bit daunting at first of course, like most things. Link to comment Share on other sites More sharing options...
Guest RodN Posted March 6, 2007 Share Posted March 6, 2007 Why not- digitalis? Best JA [/b] It runs on pro-audio levels and requires a mixer for starters perhaps? Other than that it's the bees knees IMO, offers delay as well (but I believe only a couple of bands of parametric per channel). Joz I guess with plate amps vs the likes of behringer setup you have a comprise, ease of setup (plate amps) vs integration level (parametric, 24db xover slopes, delay etc). They're awesome Joz.... Link to comment Share on other sites More sharing options...
terry j Posted March 6, 2007 Share Posted March 6, 2007 hi Ja just looked it up, there are two products usually recommended for this role,FBQ 2496 and the dsp1124. There are arguments for using either, again gone over on the shack. Hi Rod, not sure what you mean by needing a mixer???, have not used a mixer on mine.... Link to comment Share on other sites More sharing options...
norpus Posted March 6, 2007 Share Posted March 6, 2007 A great start Joz into the deep recesses Looking forward to hearing these babies once EQ'ed etc And you thought the neighbours wouldn't be happy with a once off sub day?? :blush: I'll talk to them about their experiences after a month of these puppies (thats if they don't sell up and shift before the month is up :biggrin: ) Link to comment Share on other sites More sharing options...
JA Posted March 6, 2007 Share Posted March 6, 2007 Hello Terry, I will check it out. One reason I would like to try the Berringer is that it has eq, xover and time delay in one unit. I need these now because I am experimenting with some horns and have to use a seperate crossover and active filter (for bass eq). Thanks for the suggestion I will check the Shack you mentioned. Best JA It runs on pro-audio levels and requires a mixer for starters perhaps? Other than that it's the bees knees IMO, offers delay as well (but I believe only a couple of bands of parametric per channel). [/b] Hello Rod, Yes there sure is a lot of stuff in one box- I will have to download the user manual and check it out in detail. Best JA Link to comment Share on other sites More sharing options...
JA Posted March 6, 2007 Share Posted March 6, 2007 understand ja was jsut a suggestion to hide the big suckers. [/b] Yes they are big- a couple of medium size fridges infact (250+ litres, up to 450 if you like). Anything is a good idea to hide these. Best JA Link to comment Share on other sites More sharing options...
terry j Posted March 6, 2007 Share Posted March 6, 2007 Sorry Ja I simply thought you mentioned it for Joz' bass eqing, didn't realise you were bi-amping something doh! Sure, for what you want to do it's a great thing. I used it in my system before upgrading to the DEQX, there is no way you will find me bagging it. That is not to say it doesn't come with compromises. It's Professional stuff, so the input levels etc are a pain. You, however, seem to have the nouse to fix that sort of thing (and help me with it later!). The biggest problem is the lack of volume control. It can be overcome to a small extent by having a volume control on the source. But controlling the volume that way means we throw away bits, which can lead very much to a loss of resolution at lower volume. Before I learnt that - from this forum BTW hurrah- I found I tended to play on the loud side, I now think that phenomena had a lot to do with that. The best option is to have some sort of volume control post dcx and prior to the power amps, we can investigate that later. Sorry for my stupidity, so to sum up it's one DCX for JA and one FBD for Joz. By the way, there was evidently a huge fire at the warehouse, which led to supply problems, may be back to normal now. There was also talk of supply probs with the DCX in the normal course of things, once again that may all be ok now. Link to comment Share on other sites More sharing options...
joz Posted March 6, 2007 Author Share Posted March 6, 2007 Wow joz! Congrats on the purchase ... but that was the easy part I'm sure that ajw can make a cabinet for you, but I believe you can get someone in Melbourne to do it as well. Why not try SGR ... they can probably supply a plate amp of their own design. They also do a beautiful automotive grade finish, but (in my very humble opinion) a big sub in an automotive grade finish in a living room is a bit too much. This is why ... ... I think that Alebonau is a man of taste Great suggestion! Certainly will go a long way to diminish the size of that thing. [/b] Actually Keith(sounds weird Amf)ajw was my fist thought. Only with the size of the cabinets and their weight transport was my only issue,with costs and damage.I'm sure it wouldn't be worth personal delivery,they're not Australs after all holy cow ! joz is about all I can say ! have you considered getting the boxes leather covered ? same colour as your couches and would blend in well in the room I think - presuming this is going ot be a low slung ? bench/ottoman like think that goes across the front below the pj screen. you could have the drivers even down firing to hide them visually. jsut thinkign of your current modern minimilist setup you have present. Still going to be big boxes I imagine so not sure how much hidign you can do of the boxes them selves ! wouldnt be suprised if the couple of channels spare on the elktra si plenty. they look like high efficiency drivers with a sensitivity of 95db and know ken ran his two ib 18" no probs of the elektra at one time. you could do this for starters anyways till fully explore other amp options via sgr and others. [/b] At this stage I'm thinking a lowline cabinet style,then perhaps sitting a chunky bechtop looking item over the top.(to match the kithchen. Will try the spare Elektra channels short term I be thinkun. Black grill material across the front is where I'm leaning at the mo. Guys thanks for all the suggestions so far.It seems though that off board amps are the way to go with external crossovers.With what I've heard I was believing this would be the premier choice,but I still had to ask and research this myself Anymore good ideas?Bring them on. Link to comment Share on other sites More sharing options...
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