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Yamaha sub bins and Drive rack Pa

fouronthefloorfouronthefloor Posts: 55
edited March 2009 in PA General Discussion
Hey guys. Been checking out the forum for a while and very impressed with your knowledge base and willingness to help. Play in two different situations but a quick question to kick things off at the moment. Playing in a rock duo with my mate and I on guitars and vocals. We play to backing tracks my old mate records through midi files himself to try and get a good, rock sound. Our mixer is a yamaha mx16/6fx, then through a drive rack PA then to QSC amps, PLX 3002 and from there to 2 yamaha club V SM15V and 2 SW118V. At the moment we're running full stereo to tops and bottoms but finding it hard to get a good bottom end punch. The rig is at my mate's and I plan to run the full gain structure and set the driverack up this weekend, but was wondering one small thing. Yamaha subs at 8 ohms with these amps is 550 watts. Are we better off with the subs, running in parallel at 4 ohms, bridge monoing the amp, giving us 1500W per box (potentially). Any feedback would be appreciated. I am sure I will have more questions in the near future for you guys. Thanks in advance.
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Comments

  • DraDra Posts: 3,777
    Well, that is a loaded question.
    Fact: QSC recommends your amp for that sub (stereo mode).
    Can your sub be powered by a more powerful speaker? Yes, but you have to be careful to not allow the amp to put out its full potential (crank to it's max output, clean or not). You have to set the limiters, but heavy limiting can actually do damge as well. It is really a give and take situation. You must have self control to not \"see what your system will do\" or if it is not loud enough in the size room or the size crowd to just understand that there is no more (there is more but is it worth the hundreds of dollars to recone all your speakers?)
    Crown recommends 2-4 times your speakers continuous power (300w) which is 600-1200w. 1500w is 5 times your speaker.
    As the ol' saying goes, \"six of one and 1/2 dozen of the other.\"


    DRA
  • GadgetGadget Posts: 4,915
    I guess as Dra says ...more AMP power to your speakers will elicit better results bass wise, but can also harm the speaker if a high average power is maintained in the bridged mode... Those are most likely 3\" voice coil Emminence speakers, and I could never seem to get great punch out of them, In front loaded cabs the speakers I have found need 4 \" voice coils to really get up and walk across the floor :lol: ...Any way try the bridged mode, do the gain structure as in the READ ME FIRST BEFORE POSTING section (actually the whole thing has lots of good stuff for you...

    Then the key here is balancing sound from tops to subs and maybe using a PEQ in the 80 hz area to add a little punch...

    Just remember, yes , a Ferrari can go 200 miles per hour.. but do you really NEED to... all the time?
    Gadget
  • Thanks for the replies. Will look at my options when the drive rack is properly set up. Looking forward to getting it running in it's sweet spot.
  • Just thinking out loud and a little off topic. Do we know if the crossovers in the Yamaha SM15IV are any good (turns out they are series four, not five) or would it be a worthwhile experiment to bi-amp them. We have two other amps at our disposal Australian Monitors, not sure of the model off the top of my head that are rated at 1000W @ 4 ohms. Any thoughts on the subject welcome. Will finish setting up the driverack on the weekend with the help of specs obtained from the Yamaha web site and will keep you posted. Thanks again.
  • GadgetGadget Posts: 4,915
    I GUARANTEE...once you properly bi-amp those tops...you'll wonder how you ever got along with passive speakers...ABSOLUTELY NO comparison...I've already laid out the basics for you in the FAQ section...
    http://www.dbxpro.com/forum/viewtopic.php?t=1081
    and
    http://www.dbxpro.com/forum/viewtopic.php?p=4656#4656
    Louder, MUCH MUCH cleaner/clearer, way more efficient...
    Gadget
  • Another quick question if I may. Once I have the yamaha boxes set up for our duo, I will be setting the rig up to run Australian Monitor boxes for our four piece rock band. Drums, bass, 2 guitars and vocals. I have just been emailed the specs for the boxes. Will also bi amp the tops but noticed the suggested crossover point for the subs is 150 to 250hz. This seems quite high. Any suggestions on whether this is right?

    Slam Box :D:D
    2 x 15\" drivers in a bandpass enclosure
    Continuous power handling unclipped 400W
    Short term power handling unclipped 800W
    Usable frequency response 40hz - 250hz
    Recommended crossover range 150hz - 250hz
    sensitivity 106.5db@1W/1M
    maximum short term SPL @rated input 137db
    nominal impedance 4ohms

    Top box
    There are two 12\" drivers and a 2\" hf/mf compression type drivers in a ported quasi bandpass enclosure (according to the brochure)
    Frequency response
    60hz-17khz +/- 3db
    45hz-20khz +/-6db
    sensitivity 105db@1W/1M
    SPL 130db cont
    133db peak
    power handling 400W cont
    600W peak
    impedance 4 ohms

    Can forward spec sheets if required. Thank you in advance for your thoughts.
  • GadgetGadget Posts: 4,915
    Ya, send the spec's.. I assume then that these will become the mains? Sp's to practice? or monitor duty...?

    That crossover point makes sense if your using 12\", or maybe 10\" tops(closer to 250 with the 10\") that aren't meant to go that low...It also allows the tops to have a better lo mid sound since they won't be doing the lo end.

    The xover point will depend on a number of factors... not the least of which is amp power available..application...etc, the more info the better.
    G
    tzone42@paulbunyan.net
  • Thanks Gadget
    I've emailed you the specs for our bins and the Aussie Monitor amp. The yamaha boxes will be used when we perform as a duo, where the bigger rig is just too much. We play everything through the FOH and as such have a silent stage. No guitar amps, just floor boards. My mate Bernie uses IEM and I have a small powered wedge that is oodles for what we do. Minimal equipment to lug and set up, leaving us more time to have a quiet ale or 5 :lol:

    I will bi amp the top boxes (SM15IV) and run them off the QSC PLX 3002 amps. The subs (SW118V) will be driven by the Aussie Monitor amp.

    The Aussie monitor boxes will be used in the four piece band situation. Our drummer has Roland V-drums so not trying to fight him for volume. As we can keep our stage volume to a minimum I still use my powered wedge, our bass player uses a powered wedge, and both Bernie (vocals and guitar) and our drummer have IEM. No real need for too much in the way of foldback. We are also past the \"young and bullet proof\" stage, so the amount of gear we lug is a consideration too.8)

    The basic idea is to have two very similar rigs and just select the bins as appropriate. I will probably bi-amp the Aussie Monitor top boxes as well and run them off the QSCs and run the subs off the Aussie Monitor amp.

    Thanks again for offering up your time and thoughts.
  • Just a quick update. have two gigs on the weekend with the duo, so will be bi amping the two yamaha bins on Sunday arvo, along with the Aussie monitor top boxes. Will run these from the two PLX3002 amps. Will use the Aussie monitor amp to drive the subs as they have a couple of hundred watts more power and 'old school' toroidal power supplies. Hopefully this will give us the bottom end drive and punch we need. If not I'll bridge mono the sub amp and be very careful with the power we give the bins :roll:

    Will post final crossover settings for both set ups when I dial them in. The Aussie Monitor subs have a suggested crossover point of 150 to 250hz. Will prob start around 90hz and work our way up till it gets a bit honky. Very keen to see how it sounds. Thanks for your advice so far
  • Had our first gig after bi amping the yamaha top boxes (SM15IV). Gave them a quick test in the garage before heading off to the gig but couldn't get any usable bottom end out of the two yamaha subs (SW18V). We had the aussie monitor amps (600W @ 8 ohms, stereo) running hard and the bass response just wasn't happening. We plugged the Aussie Monitor subs in as a comparison --

    2 x 15\" drivers in a bandpass enclosure
    Continuous power handling unclipped 400W
    Short term power handling unclipped 800W
    Usable frequency response 40hz - 250hz
    Recommended crossover range 150hz - 250hz
    sensitivity 106.5db@1W/1M
    maximum short term SPL @rated input 137db
    nominal impedance 4ohms

    and there was a huge improvement in bottom end so decided to use these bins at the gig, as it's a nice big room. I just don't think the yamaha subs are efficient enough to do the job we're after. We will be building two of Gadget's suggested subs with P audio C15-600EL drivers to try and get the frequency response we so desperately need :wink:

    So the set up for last night was

    Two yamaha SM15IV (bi amped, making a huge difference, thanks Gadget, and the sound seemed clearer and a little more \"forward\") run by two QSC PLX 3002 amps. The Aussie monitor subs were powered by the Aussie monitor amp (1050W @ 4 Ohms).

    Subs were crossed at

    HPF BW18 @ 40Hz
    LPF LR24 @ 106Hz

    Mids
    HPF LR24 @ 106Hz
    LPF LR24 @ 1.7kHz

    Tops
    HPF LR @ 1.7kHz

    Put a little PEQ in @ 80hz, bell shape, Q of about 5 and gain of about 3 (from memory).

    Any thoughts or suggestions would be much appreciated. Thanks
  • Sorry, one last quick question

    The QSC amps have a bridge mono dip switch on them but the Aussie monitor one does not, but the spec sheet states they can be run bridge mono. To bridge mono the Aussie monitor amp, do you run channel channel two input inverted to channel one (reverse pin 2 and three on the input lead) and bridge the negative terminals on the speaker outputs and run the speakers off the two positive outputs? Thanks again
  • GadgetGadget Posts: 4,915
    I'm not surprised. As I have stated numerous times those front loaded subs with 3\" voice coil drivers just don't cut it! Wait till you hear the boxes I put on the site... they KICK ASS! and are smaller and more portable than the Yamaha's! Like the SW18V, the Peavey PV 118 sub sux... but the SP118, SP218, and QW subs ROCK! IT takes a large motor structure in a front loaded design to get a sub that \"gets up and walks\"...

    Horn loaded subs are a completely different animal. There, the smaller the driver (to a point) the better bass response, lower frequencies, tighter sound, less distortion (more pure bass, sub bass)...Higher efficiency.. BUT they are bigger, heavier and harder to transport, and set up. (I wouldn't trade my LABsubs 2-4 depending on the application... 8 would be INSANE...for 3 times the number of front loaded subs. Even those little kick ass numbers I turned you people on to...There is nothing like sitting on a concrete slab and when a low 'B' note hits on the bass and you'd swear to God Almighty that the floor was moving... and NOT just a little bit...I've had people come to me worried that the building might be falling down...and one of them was the owner....(with an appropriate smile and an evil look in his eye). Nothing like em..and they compete well with subs costing as much as $8000... EACH!

    As for the the amp question... :? well, the problem is... that would seem to be the method, but not all amps are capable of withstanding the stresses of bridging...the amp needs to be stable to a much higher current draw... this amp may not meet the criteria...why after all wouldn't they add that basically free upgrade if the amp was capable of double the output...I'd contact the MFG and ask their opinion-position.

    Keep us informed because informed people use Driveracks, or other high tech solutions to maximize our sound.. I just think the Driverack gets the \"bells and whistles\" award. No other box has more entry level to seasoned sound company features than the Driverack. I have railed against the Auto EQ, but in a room less than useless.., but then in the hands of an experienced sound person it can get stunning results. It just takes a whole lot of knowledge... and that's what we do here..

    Just got home from the gig.. poor crowd, band was better than Friday night, but still in need of something, come to find out the guitar palayer, Johnny, was leaving the band..

    Next week the big country band comes to town and the bar will be WALL TO WALL... turns out this is their last performance as well...Hope everything in the \"land down under\" is going well...Have fun.
    G
  • Fanman20Fanman20 Posts: 223
    Down under is always perfect

    G
    I remember a conversation a few years ago and the person was stating that \"not all amp's sound the same when driving a sub\"

    EG
    take 2 amps
    both same power
    both same specs and freq response
    but 1 can sound sooo much better
    Is this your experience???

    (Maybe has something tho do with the power transformers)

    The Aussie monitor amp AM1600 is one that sounds sooo much better

    Fanman20
  • Hey Fanman

    We have two of the Aussie monitor amps, one is the 1600 and the other is the 1600S. I believe the 1600S has a bit more output power than the 1600. When driving subs, the Aussie monitors seem to be able to dig a little deeper than our QSC PLX amps. Probably because they have very, very heavy toroidal transformers in them (which is why we have two QSC amps for the mids and highs) as opposed to switch mode supplies, which relies on the capacitors to 'fill in the gaps'. Reading gadgets post on light weight amps compared to 'old school' transformer types, I'd have to agree that, in my opinion, the heavier, transformer type do sound more suited to subs, than their light weight counterpart.

    Gadget

    have checked the spec sheet on the Aussie monitor amp and they state they can be run in bridge mono. 1670W @ 8 ohms and 2200W @ 4 ohms. Perhaps one of these each side to power our subs when we build them?

    Take care
  • GadgetGadget Posts: 4,915
    Well, at least in professional sectors, there is some debate about that...The PSW (pro sound web) had a double blind shootout and while they found numerous things to gripe about, and completely dismissed the most awesome amp they had there (the Powersoft)because it wouldn't reach it's rated output with a test tone... but that's not the issue here.. they really couldn't tell the difference in a Mac 3600 and a Behringer 2450.. or a QSC PLX series...The kicker is, they all still post about how a Mac sounds better on top boxes than a PLX or a IT series crown. On sub duty however its a bit more subjective..there you have such words as punch and throb, or tightness as a comparison. Some stated unequivocally that the damping factor had something to do with it, but then QSC's John Roberts came on and shot that full of holes...So indicating that amp sound is subjective is understating the fact...

    In the real world.. it has been my, and my sons experience that the new lightweight amps are not as musical as their counterparts...EXCEPT the Powersoft/Digam amps...we believe that it is because they HAVE a huge capacitor storage banks... unlike most lightweight designs that rely on the Edison supply (wall current) to make up the slack that old huge transformer/capacitor bank amps had. The current batch of amps including the Crown IT series have very little storage and instead rely on a fresh inrush of current to keep the ball rolling...As I stated in the FAQ amp article, we have not been inside the Lab Gruppen amps, and have not had one to play with...but that most others we have. My son is an accomplished electronics engineer and working on a series of amps that are tiny by comparison, and yet huge on power output. with the new DSP on a chip and digital op-amps he is currently getting 500 watts @ 8 ohms...out of an amp the size of a pack of cigarettes. but I digress.. just indicating that we have some amp repair, and design history in the family, and that is our take on the status as of now.

    I know for a fact that the Macrotech amps have the ability to draw HUGE current.. the 3600 has shown instantaneous peaks in excess of 70 amps on peaks driving subs with a 2 ohm load. I have also seen it fry four 4\" voice coil subs.. no SET THEM ON FIRE when young son was experimenting when he was 18 or so...he was always curious... :shock: I know that the QSC 4050 doesn't really reach it's potential until driving a stereo 2 ohm load...That the new Mc2 amps are not much to brag about...and that the Mac 3600 doesn't like a 2 ohm load...actually it like it too much perahps.. but it becomes like a black hole... sucking in everything in it's path... The curious thing we found about the Digam amps is no matter how hard we push the amp.. it only seemed to meet out the amount of power necessary to drive a given speaker to it's power compression limit, and never exceeded that limit... that is to say, it drove 6 Labsubs (3 ohms each)(yes that's almost a 1 ohm short circuit) 3 per side, outdoors all day long in the summer sun...never got even warm...you could FEEL the subs a 1/2 mile away..and yet when put on a pair of Community dual 8\" studio monitors with dome tweeters...it made them stupid loud, but never hurt them no matter how hard we pressed...The kicker is, the Digam has similar specs as the Mac 3600, but will function as stated above on a single 15 amp circuit, run off a 14 gauge drop cord!!!!
    Therefore, the things we know:
    1. Well designed (top shelf .. Crown, QSC...) analog power supply amps sound more musical in the mid and upper frequencies... is it because like the influx of digital into the analog world, we have tried to \"warm up\" the sound with analog? I think as the old dinosaurs like me fade into history, and those brought up in a digital world permeate the planet, we will be looked back on as the generations that \"lived' with distortion, and we will be pitied...
    2. Damping factor is not pertinent.. as long as the design is a good one.
    3. Get the most power you can safely drive your subs and tops with.. that in and of itself will make your sound tighter, punchier, and cleaner...
    4. Make sure you have the power to drive the amps with (wall current)
    5. If you do a lot of equipment humping...we're most likely the only ones that will notice the difference in the sound any way..the other factor is power, and it's a big one, if you find yourself playing in places with inadequate power availability.. the MUCH more efficient amps will play louder, and have less problems...besides, if you didn't have anything to compare it too, those amps would sound fine...
    6. You need some really good speakers in order to discern the differences...actually, it takes a good room, a good sound person, a properly tuned and aligned system, and even then the differences are subtle...I can take a system that sounds like ASS and make it sing..(as long as there is that potential, but how many systems (in the small sound market) that actually sound good? I haven't heard many...but then sound is subjective. What sounds good to me might not to you...NAW... :lol:
  • Fanman20Fanman20 Posts: 223
    Found a spec sheet for the AM1600

    30 kg very heavy

    But they are tough
    I have 2 at work. They are turned on 24/7 for the last 7 years that I know of and have never failed

    http://www.jesther.com/dungeon/pdf/AM1600.PDF

    Fanman20
    Thanks for your thoughts G
  • GadgetGadget Posts: 4,915
    That's actually less hard on a piece of equipment than turning it on and off...There was a radio @ my dads place of employment that ran 24/7 from 1956 to the late 90's when he retired.. never missed a beat.

    Thanks..
    G
  • Thanks Fanman for the link. I have also found this information as well.

    http://www.audio-circuit.dk./images/sch ... wr-sch.pdf
  • Hey guys. I just got back from watching a friends band at a venue where there was a FOH sound guy and foldback guy supplied. Quick question with out notice.... why do these people insist on tearing our heads off with high frequencies in a bid to get things to sound loud. I love to see bands with a nice, well balanced system. A good bottom end foundation can make a whole world of difference. It can make an average band sound so much more enjoyable. Any who...

    We're building a couple of the sub bins recommended by Gadget. We've sourced the drivers and are now looking at the timber required to build them. The recommended timber is 18mm birch ply, but is very expensive down in Oz. The timber supplier also recommended hoop pine as an alternative but it is also very dear to buy. Any suggestions would be greatly appreciated. Basically we are aiming to build these for around the money we can sell the yamaha sw118's for. Would regular, garden variety ply cut it or are we robbing peter to pay paul here. Thanks in advance for your thoughts.

    Robbo
  • DraDra Posts: 3,777
    Piercing highs? Did it sound that way at the mix position? Maybe he was in a dead spot?

    Ply. The more plys, the more glue, the more glue, better density and weather protection. The main thing is avoiding voids to keep down resonances. Fill any that you find.

    DRA
  • GadgetGadget Posts: 4,915
    There is a difference in stiffness and strength, but regular plywood will work fine. I added one thing... You know those acoustic ceiling panels... The ones that are compressed fiberglass, and a plastic sheet glued on one side (very light weight)? I cut them and remove the sheet and glue them to the inside surfaces that would be the outside, not the braces. That should help the regular plywood by damping resonances, and they are cheap here.. you could use carpet backing, foam or whatever but be warned loose fiberglass will blow out of the holes and shower the building :shock: :lol: you won't believe the amount of air those things throw! I used 4 in a cassino setting with a pair of Peavey SP4 tops triamped.. WOW I had so much PA it was crazy.. I couldn't use 1/3 of what I had for volume, and it sounded so tight and rich...1 is impressive, 2 is very good, 4 is wild, 8 are nuts! Whenever possible, put them together, and get 3db of gain free, put them against the wall, and get 3 more, a corner adds 6...cool huh?

    G
  • Thanks guys.

    DRA. I thought the same thing so did a quick walk past the mixing desk but same result. Admittedly, it's a tough room in terms of size and shape, but were people are dancing and sitting listening should be the priority. When I walked around well past the dance floor, it was a little better. Maybe this was taken into account. In the main listening area it was just too painful.

    Thanks for your thought gadget. Will get to building our subs soon and keep you posted.
  • Gadget

    I have a question relating to guitar cabinet speakers and hope you don't mind me asking it here. I know it's not drive rack related but I thought you might have an opinion. I play my guitar through a GNX3000 modelling floorboard which is plugged into my Marshall JMC900 with two 12\" celestion vintage 30's in an open back cabinet. I just can't get it to dig deep into a nice, smooth bottom end drive. Money's tight so I'm stuck with the amp but may be able to spring for new speakers or build another cabinet to sit under my combo. I plugged the amp into my friends Mesa Boogie cabinet with four 12\" celestion black widow drivers in a open top, closed bottom cab and found a sound closer to what i'm looking for. Ideally I'd like to replace the two drivers in my cabinet for something that is a little more full range and not so hot in the mids and highs. Is there something suitable or do i need to look at building something to suit. Any thoughts would be appreciated. Also, took delivery of two p audio speakers to build our subs so will let you know how they come out. Thanks again.
  • GadgetGadget Posts: 4,915
    Try this first, Build a baffle and close the back off on the combo. you can just duct tape it in at first to try this, the Idea is that with the cabinet closet the air inside loads the speakers and damps their action a bit...I have three cabinets and they all sound so different...my favorite by FAR is my closed back 2X12 with ... you guessed it, Vintage 30 ... Celestions... :shock: If you want more low end (which in my opinion a guitar DOESN\"T need.. because it won't cut through the mix as well.. and thats the bass's job anyway) cut a hole in the baffle (port it) and you'll get more low end, a little experimentation will be necessary to get the right volume of air exchange.. but I think closing the back may be to your liking... some batting in the back can lower the Q with a vented cab also...

    G
  • Fanman20Fanman20 Posts: 223
    greatings

    Your question
    why do these people insist on tearing our heads off with high frequencies in a bid to get things to sound loud.

    One possibility is the sound \"sound guy\" has been mixing far too many loud gigs and his hearing has been damaged or ears haven't had time to recover from the last gig
    He is now pushing the highs to replace that he \"thinks\" the system is missing but in fact it is his ears that are \"missing\" though freqs

    Too much wax in his ears???

    Fanman20
  • Thanks G

    Just as I was about to pass out last night I thought about closing in the cab as another option , just as you have suggested. Will give that a go this week and keep you posted. Thanks again.

    Fanman

    Went to another gig two weeks ago and same thing. Great band, very loud but also very painful. Noticed that the young bloke doing the mix didn't venture from the side of the stage much though.

    Take it easy...
  • Hey Guys

    Just a quick update. We're in the middle of building two fane designed subs with p audio drivers (as per Gadgets recommendation) and really looking forward to hearing them. I've got no doubt they'll power harder than the yamaha SW118V's ever could. If they suit our needs, we will build another two (then 3, then 4, or do we just go with the labsubs?....). We really appreciate the time and effort you guys put into helping us dial in our sounds. I've got no doubt I'll be asking for more help and opinions in the future. Thanks.

    Robbo
  • Played a gig on Saturday night and with the help of your suggestions had an absolutely cracking sound. The sound guy had everything sitting in its pocket perfectly. Everything was so clear. The bar manager told us it was the best sound he had heard there. So thank you.

    I have bi amped our top boxes (and recommend it to EVERYONE) and have been told by a couple of people in 'the know' that I should now put a capacitor in series with the horn to make sure it doesn't get damaged by any thumps... Any thoughts on this one. I figured being all digitally processed this would be extremely unlikely, but if we lost power and got the thump that way???

    thanks again guys... :D
  • DraDra Posts: 3,777
    Every DRPA user should have a UPS (battery back-up) for at least the DRPA, but in reality all the processing (not amps) gear. Won't protect against improper turn off sequences, but....

    DRA
  • GadgetGadget Posts: 4,915
    Actually we recommend a UPS (uninterpretable power supply) for the DRPA .. even a really cheap one will prevent the thump if the power fails,, or there is an inadvertent switch off...Lots of threads here about that. As for transients set the limiters and you should be fine...Anxious to know what you think of the speakers.. actually I know you'll love them. They kick ASS! The labs are awesome but BIG and hard to move and pack.
    G
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