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Yamaha sub bins and Drive rack Pa

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  • Giving the Fane designed, P Audio loaded subs a run tomorrow for the first time. Will be running them (two of them in parallel) from a bridge mono Aussie Monitor amp that should give us 3000W at 4 ohms, or 1500W per box (3.5 times RMS value of the driver). Hopefully this should give us the giddy up we're looking for. Any thoughts on the amp power would be appreciated. Will post results tomorrow.
  • GadgetGadget Posts: 4,915
    That should be good to get those to \"Giddy up\"... and no that's not too much power...I have used them with a Crown 3000 watt amp and they could take even more... (600/1200/2400watts)I think your really going to like those little puppies... especially at the end of the gig when you have to load them out...\"Bass you can pick up and carry at the end of the night\"...I'll be interested to hear what you think...

    Gadget
  • Well, gave the subs a run today. I may have to go to the dentist and have some fillings replaced. These things hammer...

    When we first fired them up, there was a noise coming from them that sounded terrible, kind of like extreme distortion, but not. Turns out the castors we put on them were rattling like nobodies business. The Yamahas didn't have the ability to even get a peep from theirs. Took the castors off, plugged the holes and they performed brilliantly. We're now building a panel the same size as the back with the castors on it, that will velcro to the back to make it removable.

    The Aussie monitor amp doesn't have the DIP switches to bridge mono it, so I fed the signal into channel A and ran a link to channel B with pins 2 and 3 swapped on one end to invert the signal and ran the bins off the two channels positive output terminals. Ran perfectly.

    Using these subs, we were able to run the top amps harder, as everything was a lot more balanced. Really looking forward to using them at the next gig. Will take some photos when they're 100% finished. I'm sure two more will be under construction before long. Thanks heaps for your help on getting our sound dialed in and I' recommend these subs to anyone.

    Robbo
  • Here are the photos of the new subs. I hope the link works OK. We covered them with speaker carpet to give them a more civilised look at the local bowling club gigs and to match the Yamaha top boxes and had the grills powder coated. You can see where we had to remove the castors at the back.

    Looking forward to hearing them at a gig :D:D

    http://viewmorepics.myspace.com/index.c ... mId=993372
  • GadgetGadget Posts: 4,915
    Very nice..The links worked great. pound for pound you can't beat em...get it pound :lol: I crack myself up...

    Anyone need a kick ass PA? looks like the last live rock bar is about to be history.. and me along with it...

    G
  • DraDra Posts: 3,777
    :shock:
    :?
    :(
    :cry:

    Seems like every year at this time you go through this.

    DRA
  • DraDra Posts: 3,777
    Robbo, What was your cost to build the 2? Did you hire out the wood work or do it yourself? What did you for grill material? Source?

    Gadget, The Fane build instructions say to use the port length specified on the drawings. Looked and looked, but I don't see them.

    Thanks,
    DRA
  • GadgetGadget Posts: 4,915
    Ya.. the last rock bar is closing after next weekend... so the system will be sitting in a trailer..only parties and outdoor gigs now... :cry::cry::cry:

    As for the port length...162mm....It's the second line on the technical data sheet under the picture..

    I think 2 took about 1 1/2 sheets of 3/4\" 16 ply...I think it was like $34 a sheet...Parts express...the corners are $.60
    http://www.parts-express.com/pe/showdet ... er=260-708
    Handles
    http://www.partsexpress.com/pe/pshowdet ... er=262-832 Are $.55 each right now...

    I bought the good exterior paint and a knap (texture) raising roller for about $20...The Pipe was like $10... for a length... @ Loudspeakers plus the P Audio challenger series EL drivers are about $120 each plus shipping ... came out to like $300 with the speakon connectors and all...Glue.. use Poly Propylene..(gorilla glue... but generic) $8... home depot ...So even if you paid more for the wood... under $500 for a pair...I have only made the 15\" but the 18\"s could be close price wise but the difference in performance and the added size and weight I thought... well... and went with the 15\"...

    Did a gig with 4, and a pair of bi-amped Peavey SP4's Kicked ass all over the place...
    They really kick ass... pound for pound the best sub for the money...period...
  • DraDra Posts: 3,777
    My (2) Yorkville SW800's (old LS808) sound fantastic and even though they are rated 400w RMS, I can't seem to get them on an amp with more than 600w. When I do (had 1300w, then 1100w, now 750w) and throw rap crap at them they on occasion will pop or snap like the stops are being hit. I have moved the HPF all the way to 50hz. Limiter is set to hard limit with 2db over shoot a little before 80 volts, which is where the 750w amp starts thinking about clipping. They are loaded with the factory RCF's. The only damping material in these (front loaded but with quasi-horn rear reinforcement) is a 2 x 2 open cell foam piece in the speaker chamber. Would more damping help? Hurt? No change?
    But otherwise, they really do sound great. Maybe the 700,000 cu ft gym I was in had something to do with it, but it still should be able to take all the power the amp had to offer. Right?

    DRA
  • All up the cost came in around AU$1300 or AU$1400 for the pair I think. We had the work working gear available to us and it made a huge difference. We had a table saw, router, jigsaw and everything else we needed. The price also includes two boards the same size as the back with 4 castors on one side and velcro on the other. At the end of the night we slap the board on the back of the sub, throw it on its back and roll them out. We got the grill at a good price of $45 each from memory and had them powder coated for $40 each. I'm sure there are cheaper options out there but they look great and are road ready. We used nearly two full sheets of ply but just used pine ply and filled any voids. It took us a while to find the port lengths too as they're in the specs rather than shown on the drawing. We bridge monoed our Aussie monitor amp to run them in parallel, which gives us 1500W per box. We only gave them a run in the garage at home but they sounded great. We have our first gig with them on Friday night. Will report back how they go under battle conditions.

    Robbo
  • GadgetGadget Posts: 4,915
    Sorry Dra... damping material won't help... make sure the chamber is sealed though... absolutely NO AIR LEAKS. Those could be 3\" voice coil woofers.. if so that would be indicative of why they .... wait... how many hours are on them? I have RCF's in my tops and they got really flabby and I had to recone them...

    Gosh that seems like a lot? Like I said I built a pair for around $500US... and our money ain't worth doggie excriment any more...
    Gadget
    Inquiring minds...
    :!: :wink:
  • The drivers were about AU$350 each here in Australia and heavy duty carpet is more expensive than we figured on, as were the castors. The Yamaha bins we replaced (SW118V) were AU$1100 each new, so these cost us around the AU$600 mark each and are far more impressive. Things like corners and handles and pole mounting gear, speakon connectors added up REAL quick. :roll: Anyway, they ended costing us a little more than we first budgeted (thought we'd build them for around AU$500 each) but they'll suit us down to the ground. We actually have enough carpet and ports to build another two.... :lol::lol::lol: but that's another post...
  • DraDra Posts: 3,777
    They were reconed about 3 years ago. I doubt they have 200 real use hrs on them. These cabs had the factory XLR connectors and I changed them for speakon, but didn't get the \"sealed for speaker use\" ones. I guess I should silicone or hot glue the input panels up good. The original cones were popping (before I changed the input panels). That prompted the recone, although the reconer said that they were in pretty good shape.

    DRA
  • GadgetGadget Posts: 4,915
    NO AIR LEAKS....that is problem one to solve...the back chamber must be sealed so that the cone damping is proper... you didn't say which driver they used? I once talked to the guys at Yorkville who strongly urged me to get a more powerful amp for my tops.. I was only using a Mac 3600... :shock: kinda thought that was funny...

    :lol:
    G
  • DraDra Posts: 3,777
    RCF L18/851 4 ohm version, but in the cab, presents an 8 ohm load to the amp. I confirmed that with Yorkville.

    DRA
  • GadgetGadget Posts: 4,915
    Looks like it's a 3\" voice coil? If it's less than 4\" that would explain the power handling... were the recones done with RCF kits?

    Gadget
  • DraDra Posts: 3,777
    Yes, I even went with the upgraded flatwire coil. I just looked and the current LS808's use B&C, custom I believe, because the number 7458 does not show at the B&C site. But listed as 4\" VC. Sent you a PDF.

    DRA
  • GadgetGadget Posts: 4,915
    Is that a sealed chamber under the cone end of the woofer? I assume so? Ya unfortunately with a three inch voice coil and that design you are getting all you will ever get out of that speaker...If I had the Theile small parameters I could maybe suggest a better woofer for that application in a 4 \" VC but without the parameters it's a no go...
    Gadget
  • DraDra Posts: 3,777
    http://srforums.prosoundweb.com/index.p ... msg_372320
    There may be some gleenable info in this thread (one page).

    As far as the chambers goes, the woofer is reflex mounted and has that inner chamber that exits up, back, down, forward and out. The theory is that the cabinet fire forward like a normal reflex and the back wave travels out the \"horn\" and reinforces the front wave. The entire horn length is the full width of the cabinet. The inner chamber is also full cabinet width with no ports.

    If a 4 ohm speaker is put in an enclosure that loads it to 8 ohms for the amp... What happens if you put an 8 ohm speaker in that same enclosure? Stays 8?

    DRA
  • GadgetGadget Posts: 4,915
    You know... that is kind of a manifold design then...and I can definately see why the woofer blats out... I'd put a couple of those P audio challenger series EL woofers in there... they would work good as well as the Eminence omega 18, or even the lo rider by peavey... that is ascending in price I believe the P audio and the Emminence are similar in price...

    G
  • Just a quick opinion seeking exercise here if I may. While trying to nut out how to bridge mono our amp manually (no dip switches, just hard wiring) I drew up some waveforms to get an idea of what's going on. In plain old garden variety mono form our wave goes above and below our reference point, say 50V above and 50V below, producing our output. If we bridge mono the amp, our voltage is now referenced to its inverted self, so when output A is at 50V, output B is -50V. This means we have 100V across our load. This is where our 4 times the power comes from (ignoring our amps internal losses). If we assume our frequency does not change, our bridge mono amp has an output of 100V compared to our non bridged mono output of 50V but they take the same time to do it. Will this change the way it sounds. Will this provide more punch and attack or would the differences be negligable? Just a thought. Thanks for your thoughts...

    :?

    Off to try our subs...

    Robbo
  • DraDra Posts: 3,777
    Gadget, check your PM.
  • Well, we've had two gigs with the subs now. These things are loud. We had to keep the volume down a little as there was a boomy resonance coming from the subs that was verging on unbearable. It seemed to be in the lower bass guitar frequency. We put a layer of wadding inside the boxes when we built them (white fluffy from a craft shop) but I was thinking we may need some more. On stage it was really loud, but out front it sounded fine. Maybe it was just the way we had to set up in the venues as the bass would of been funneling towards us a bit. Any thoughts are appreciated.

    Thanks

    Gadget. Thanks for suggesting these bad boys. I know we'll get these dialled in and have the sound we're looking for.
  • GadgetGadget Posts: 4,915
    You my friend have probably got that stage din that has the bass welling up in all the mic stands and open mics...First HPF all the instruments that DON'T have any business in the subs.. Roll off the low end on vocals as well, and play with the instruments to find those that need the low end, roll the others off a bit.. like guitar...the only things that should be in the subs are the Kick, Bass, Keys (if any) and the floor tom... the rest shouldn't be...Perhaps you will even have to go with Aux Fed Subs... Perhaps a bit of attenuation @ 60-80hz would help.. but most likely 100 hz... 200hz and 4-500 hz (room resonance) now that you have kick ass subs.. Remember that any sub isn't flat over a very large area.. and the peaks in the subs are likely to be up to 30 db hotter than the average...
    G
  • Thanks for the reply G and thanks for taking the time to help us out. We've got two vocal mics and a silent stage. Our two guitars go through modellers then through the FOH. We play pre recorded backing tracks through a stereo channel and have a small powered wedge for foldback, and its usually barely running. We turned the monitor off to see if that was the problem but it made no difference. Then I grabbed hold of the low EQ knobs on the vocals and turned them to nearly off (we have the 80Hz hpf on both vocal mics on). This made a bit of a difference but the din was still roaring. We're now considering rerecording our backing tracks to mono, with kick and bass on one channel and everything else on the other. Is this the way to go to aux feed the subs? Thanks again and any thoughts are appreciated.

    Robbo.
  • GadgetGadget Posts: 4,915
    Hmmm.. I think I'd try using a PEQ on the subs and set a Q of 1.5... and a 5.0-6.0 cut and sweep the 50-100 hz range and see if you can't take care of that rumble.. it may take a bit more cut than that but a little experimentation should help find the fix... try that and report back..
    G
  • Thanks. Shall do. Our next gig is on the weekend, on 27th so we'll try it then and let you know.
  • DraDra Posts: 3,777
    Are you doing any \"weird\" routing with the bass guitar or other low frequency inputs that could cause an internal feedback loop? Can you stop the roar by turning off channels?

    DRA
  • DraDra Posts: 3,777
    Gadget, back to my cone popping problem. I posted to PSW and one guy there suggested that because it is rap that causes the problem (real content down to 30hz and relatively little in the 70 - 100hz range and the fact that 30 - 60 hz is 8-12 db hotter than any other band (including tops), using the RTA internal A&B source) and I was HPF'ing 45hz, then 50hz trying to \"stop the pop\", that the filter may be the cause. Trying to get loud in the sub region (50 - 100hz) when all the content is below that (30 & 40 hz), so to solve the problem, the best solution is to drop the HPF to allow that content through. More content at less power = more volume with less excursion. It seems to make sense. Thoughts?


    Robbo, Have you run any rap through your system at high volumes to see how the new subs do? How do you have them Hi Passed?

    Thanks,
    DRA
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