He did mention a dbx in a previous post, and again in the post before this one, the model number he just gave does indicate that this unit is a crossover. Not a good crossover but a crossover nonetheless.
2) Even in the smallest clubs, the usual distance from a cheezy 6 foot deep stage to where the usual weekend warriors place their mains speakers is at least 6 feet. Perhaps you frequent smaller parlors.
3) Agreed, but there is no reason to FUBR (FIBUR) sound before it reaches the patrons.
Oh, there are worse things than this. This 1/4 wave distance "rule" is broken all the time.
Almost 100 percent of mtm speakers have 2 mids placed a foot or more apart, playing the same frequencies with a high crossover point of 2 khz or higher. Lots of waveguide tweeter designs with round waveguides break this rule since there's no way to get the mid and tweeter close enough together. And both of these examples break the rule in the much more critical mid/tweeter crossover frequency range.
It's a rule for a reason, I agree with that, it's definitely the proper and best way to do things. But it's certainly not the end of world if you don't do things perfectly. Life isn't perfect, sometimes lobing happens and sometimes crossovers are not perfect. That's no reason to rule out experimentation.
Maybe, maybe no. OP still doesn't know series from parallel despite having a picture posted and having seen me describe how important it is several times now. Do you really trust his description of how the system is running? He did say he is clipping the amp, he just didn't confirm which light is actually lighting up.
I have no idea who that is but sorry for your loss.
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You should buy a meter, it will come in handy, and you can get one for as little as $5 so there's really no excuse to not have one. But that is NOT an excuse not to learn the absolute basics. It's absolutely mandatory to learn stuff like series vs parallel wiring and how to check polarity. If you can't do stuff like that you have no business at all doing this kind of job for money. I'm sure you are a great drummer and I'm sure your band is great, but if you can't do the electronics hire a sound guy. I'm sorry to be so blunt but I posted a clear and simple picture - if you can't interpret that picture and tell whether you have your system wired in series or parallel you are not qualified to set up and run the electronics.
Lets assume everything's stock and works as it does in every other setup. Connecting two cabinets with any conventional connector puts them in parallel. Its a very weird bit of wiring to get it any other way.
Something to check before you go any further is this: you've set your NU3000 for bridge-mode, but have you changed the wiring accordingly?
Bridged output is across 1+ and 2+ of channel A's output. I suspect you're using a store-bought speakOn cable, which will only take signal from channel A. You're probably only using one channel, non-bridged, and getting 300w per sub at clip.
You'll need to make a special cable up that goes from the amp to the nearest sub. At the amp end, the red wire goes to 1+, and the black goes to 2+. At the sub end, red to 1+, black to 1-. Label that cable, keep it permanently attached to the amp, whatever. Just make sure that the correct end always goes to the amplifier.
Next up, you have a crossover. Lets use it properly.
On the back, make sure the crossover frequencies are x1 (not x10), set for stereo, and engage the Low Sum option.
You want to go desk => crossover inputs => top amp (left and right)
//////////////////////////////////////////////=> sub amp (one channel only).
All of these connections should be XLR. Ignore the forward-slashes, that's the only way I've found of getting things to display properly.
On the front, set the crossover frequency on both sides to be 100Hz. Engage both 40Hz filters. Make sure none of the invert buttons are pressed.
Next up, with amps and speakers connected and positioned as you normally would have them, play some music. Turn the volume controls on the amps all the way up (just the left one on the sub amp), and control the volume from your mixer. Adjust the low-frequency and high-frequency outputs on the crossover so there's a good balance of bass.
Next up, play a 100Hz test tone. Not too loud, just so you can hear it clearly. There's lots of free apps for phones etc that will do this.
Press the two buttons to invert the high outputs.
Does the 100Hz tone get louder or quieter? Press those buttons again to check.
Once you've decided (you want the louder setting), remember those settings in case the crossover ever gets messed with.
Chris
Something to check before you go any further is this: you've set your NU3000 for bridge-mode, but have you changed the wiring accordingly?
Bridged output is across 1+ and 2+ of channel A's output. I suspect you're using a store-bought speakOn cable, which will only take signal from channel A. You're probably only using one channel, non-bridged, and getting 300w per sub at clip.
You'll need to make a special cable up that goes from the amp to the nearest sub. At the amp end, the red wire goes to 1+, and the black goes to 2+. At the sub end, red to 1+, black to 1-. Label that cable, keep it permanently attached to the amp, whatever. Just make sure that the correct end always goes to the amplifier.
Next up, you have a crossover. Lets use it properly.
On the back, make sure the crossover frequencies are x1 (not x10), set for stereo, and engage the Low Sum option.
You want to go desk => crossover inputs => top amp (left and right)
//////////////////////////////////////////////=> sub amp (one channel only).
All of these connections should be XLR. Ignore the forward-slashes, that's the only way I've found of getting things to display properly.
On the front, set the crossover frequency on both sides to be 100Hz. Engage both 40Hz filters. Make sure none of the invert buttons are pressed.
Next up, with amps and speakers connected and positioned as you normally would have them, play some music. Turn the volume controls on the amps all the way up (just the left one on the sub amp), and control the volume from your mixer. Adjust the low-frequency and high-frequency outputs on the crossover so there's a good balance of bass.
Next up, play a 100Hz test tone. Not too loud, just so you can hear it clearly. There's lots of free apps for phones etc that will do this.
Press the two buttons to invert the high outputs.
Does the 100Hz tone get louder or quieter? Press those buttons again to check.
Once you've decided (you want the louder setting), remember those settings in case the crossover ever gets messed with.
Chris
"Just a guy" I literaly answer your questions and comprehend what you say for the most part, yet you disregard it, talk in circles, and call yourself "blunt". You really haven't been a much a help at all, so feel free to leave it to someone who can teach it better and who has patience for a beginner like myself. I'm not looking to be a professional, just need help getting started. Thanks though.
Chris, you explained everything perfectly and concisely and I'll be sure to do all of this as soon as I get home. Didn't expect such a thread from just wanting new speakers in my subwoofers! I learned a lot though. Thanks to everyone for chiming in.
Chris, you explained everything perfectly and concisely and I'll be sure to do all of this as soon as I get home. Didn't expect such a thread from just wanting new speakers in my subwoofers! I learned a lot though. Thanks to everyone for chiming in.
Xalanx309 JAG's post #32 is important (and is basically illustrating what I was talking about in my first post). If wired the first way you have four ohms, if wired the second way you have 16 ohms (and very different spl outputs). The polarity is also very important (ie both drivers connected the same polarity). if opposite then they are 180 deg out of phase with each other and cancelation will result.
This is what he is referring to as the absolute basics. Also the two main things I mentioned in my first post. It is important to get this right
I think from what you have described it seems likely the wiring is parallel, I think all JAG was after was a confirmation.
Sometimes people helping get a little hot under the collar if they are frustrated. Not condoning it, but I think JAG is just trying to help like the rest of us
edit: in case it isn't obvious, these questions are to determine whether you have a problem that can be fixed without any need for an upgrade
Tony.
This is what he is referring to as the absolute basics. Also the two main things I mentioned in my first post. It is important to get this right
I think from what you have described it seems likely the wiring is parallel, I think all JAG was after was a confirmation.
Sometimes people helping get a little hot under the collar if they are frustrated. Not condoning it, but I think JAG is just trying to help like the rest of us
edit: in case it isn't obvious, these questions are to determine whether you have a problem that can be fixed without any need for an upgrade
Tony.
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IIRC I've only asked one question (maybe 5 times now) and it hasn't been answered. I haven't disregarded anything, I've been paying very close attention. Maybe a quick overview of what's actually happened will help you to understand why I'm being blunt.
1. In post 1 you said "The 2 subs are daisy chained, so if I understand correctly, they're now sitting at 4ohms."
2. In post 25 you said "I had a buddy tell me that because I daisy chain my 2 enclosures that I'm sitting at 16 ohms??"
3. In post 31 you said "I've been told that daisy-chaining is technically wiring in parallel, and that prallel wiring divides speaker ohmage. "
4. In post 40 you said "I'm not 100% sure on my ohmage so I may just buy the meter reader.
That's about all you've said on the matter of series vs parallel wiring, could you please point me to the definitive answer to this question?
Here's the deal. It sounds like you have no idea how series vs parallel works and it sounds like you listen to your buddies a lot, buddies who may or may not know anything at all about anything. It's ENTIRELY POSSIBLE that you are using custom cables that wire the cabs in series even though they are "daisy chained". But as most people have pointed out it's most likely to be wired in parallel, as this is a much simpler way to do it and you probably don't have custom made cables. It's also entirely possible that your buddy that told you that it's 16 ohms made you cables that indeed give you a 16 ohm load. There's no way for anyone to know what you're doing because we can't see it and your comments on the situation have been incredibly unhelpful.
Either way, series vs parallel is very important and you haven't answered that question.
In addition to that, your comments on your clip lights are also very confusing.
1. In post 13 you said "The indicator in the sub amp usually hit's the dot right below the clip,
2. But in post 31 you said "I usually try to get it where it only clips now and again, but never constantly."
So which is it? The clip light or the light right before the clip light? This is a very important distinction as the two lights are several hundred watts apart.
Moving on,
1. In post 27 you said "Also, I feel like I may not be properly wired-through when it comes time to my whole rack set-up. and went on to describe your hot mess of a rack wiring situation.
2. In post 40 you said "I mixed things around and here how it's hooked up now. I now have just one output from the main R out to my crossover (is that ok? Or do I need to use both L and R outputs??), high out goes to the ultramizer (which I have bypassed) then that one line is split into L and R to my amp which is in stereo mode, and low out simply goes to the amp. This is incredibly unclear but doesn't sound right.
Additionally you've asked a few questions along the way that have already been answered.
Now can you kind of understand how we got to where we are?
You haven't been much of a help either, you haven't answered simple very important questions, your descriptions are vague and unhelpful, and instead of choosing to learn a bit and answer them you have chosen to ask me to leave. That's fine, and good luck to you. Just know you will get your answers a lot quicker if you take some responsibility for your own education here, understand what you are doing. This will also serve you well in the future. If you know what you are doing you won't make wiring mistakes and you won't have problems. If you don't know what you are doing it's just a matter of time before you mess everything up and are unable to perform your show because you can't figure out what's wrong. This might seem harsh but I've had more luck getting straight answers from toddlers. When I try to help I expect precise answers to basic questions.
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Xalanx,
"Bones" McCoy voice: "Jim, I'm a Doctor, not a bricklayer!"
That said, I'll try to lay some audio bricks for you. As a drummer, you know the beats (better than I, correct me if I get them wrong in the upcoming analogy), think of the "One", as polarity- the speaker cones move forward (repelled from the magnet) with positive voltage applied to the +/Red terminal (unless they are old JBL speakers, in which case they suck inward). Polarity, like the "One", is universal- the speaker is on the beat, or one-half beat off (like many beat-off musos..). On the other hand, (or foot) you have phase, which is (kind of) like the high-hat, there might be Four beats of the hat to get back to the One. It does not matter where the One is, as long as the left foot keeps stomping Four times as fast as the One, everything stays "In Phase/Time".
OK, so far, so good- but speakers, like musicians, have timing (Phase) issues- if the half deaf blind banjo player does not know where the One is, he may come in late, and on every One, get another sixteenth note further behind the universal One. So what does one do to get Banjo Bubba to play in time (Phase) ? The cruel answer would be to fire him, and replace him with a good player (a Time/Phase aligned powered speaker with built in DSP), but we are kind and all One folks, so instead we gaffer tape headphones on his head like Keith Moon and play a click track with the One cracking like a whip through his thick skull, and hey presto, BB is now playing in Time (phase) with the rest of the band. Bubba will now complain that he can't hear his Banjo, so you will turn that up in his cans, and now he can't hear the One again, and you give the sad sack the heave ho.
Ok, now you know all about Phase and Polarity. Back around 1995, good DSP (which can adjust time/phase, not limited to One polarity choice) was damned expensive, and being burned by a cheap, horrible sounding DSP purchase, I decided to purchase a cheap, but good sounding DBX 223. It only "plays" on the One (with the polarity switch you can delay the One by a half beat) but hey, it sounds good. One funny (ha ha) drawback of it's design is the "40 Hz" HP filter, which is supposed to cut the lows out below 40 Hz, gets "lazy"and gives up around 10 Hz and lets dropped mic impulse noises and warped record rumble flap your woofers around like a washing machine loaded with a brick.
In the picture below you can see the frequency response (lower portion) and phase response (upper portion) of the venerable (like the clap, or other VD, it won't go away) DBX 223 crossover set to around 800 Hz. Note the Purple (for our dear departed Purple Reign Mpls. Mn Musician, who can be seen humping my speakers on film) phase response is pretty well flat up to the crossover region, but is 180, out of 360 degrees off from "0" degrees due to the Polarity switch being engaged, or the connecter Polarity was reversed, either of which have identical results.
The DBX223 uses 24 dB per octave filters, also known as Four Pole Filters- each "Pole" being a (virtual) capacitor or coil of wire causes a 90 degree Phase shift, note the upward shift in Phase the crossover causes above 800 Hz, and the corresponding "funny" phase response the (lousy) "40 Hz" HP filter causes. A 24 dB crossover has 360 degree phase lag, the One is a beat behind at the crossover frequency. Fortunately, at 100 Hz, the beat is only 1/100 of a second long- to short for anyone other than golden eared baby girls to detect.
With modern FIR filter DSP it is possible to have steep (24 dB per octave or more) crossover filters and perfectly flat phase response, with one caveat: the lower the frequency flat phase is achieved, the later it is compared to the One. For playback, a 1/4 second delay makes no difference, but for live sound that's the equivalent of the time distance sound takes to travel over most of a football field, hello Banjo Bubba in a Box.
To sum up, polarity and phase are related, but different, and require different tools to measure them. Although flat phase can be a good (some would say great) thing, the most important detail is to match the phase of the different speaker components through the crossover region. Each speaker component also imparts phase change due to the nature of wound voice coils, capacitors, bass reflex (phase inversion) and horns all contributing their own phase lags in addition to the active crossover phase lag.
Direct answers to your post:
1) You tested the polarity of your subs, not their phase, phase changes with frequency.
2) Using the Right out is OK. Keep all pan pots center, or pan them all to the right. Center is best, keeps your headphone mix balanced.
3) You only need to use right and left if you want your mix in stereo. Effects do sound better in stereo, and mixing in stereo in small clubs allows you to put things like a too loud guitar to only the side it is not too loud on.
Art
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Wired in parallel by linking two separate cabinets by speaker cable (most videos I've watched on this subject [by professionals] call this daisy chaining), 4 ohms, most of the time my signal hits the -6db light but with occasional instantaneous clipping.
Chris, are TRS cables acceptable at all?
Chris, are TRS cables acceptable at all?
Yes, the term "daisy chaining" is often used to describe hooking up cabinets.
Short term clipping presents no problem to your speakers, and is typical for a human drummer playing dynamically.
The DBX 223 measured in post # 47 was connected to the measurement device using a 1/4" TRS to XLR adapter, standard wiring is pin 1=Shield/Ring, pin 2=Tip/+, and pin 3=Ring/-. The pin 1 connection can be "lifted" at one end to eliminate hum caused by a "ground loop".
TRS or XLR cables are functionally identical, both offering balanced operation. The TRS is simply a smaller, non-locking connector that can't be daisy chained without using a "Chinese finger" adapter between cords.
Your prior hook up using a (presumably) TRS cord from the headphone output would put the left side of the mix on the tip, and the right side on the ring, which can result in some very odd behavior depending on effects and pan pot position. Using a standard 1/4" cord from the headphone output would short out the right side of the headphone amp, usually not a fatal problem, as most board put resisters in series to avoid the magic smoke coming out if a 1/4" is accidentally (or intentionally) plugged in.
Art
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"Well, that escalated quickly"
I would try TRS from U16 to XO but the XO is your weak link. I don't think you really need the Ultramizer with the U16. I would probably sell it and the DBX and upgrade XO to say a DCX2496. Might be an even money deal. The 2496 will give you a ton of flexibility and cure a multitude of issues that were brought to your attention. I would then go balanced XLR from U16 to 2496 and then XLR to NU3000. Easy peasy. I think you will get a nice bump in output to subs once all is dialed in but you will still need to upgrade from Peaveys subs. Pretty much any design around these parts will wipe the floor with them.
I would try TRS from U16 to XO but the XO is your weak link. I don't think you really need the Ultramizer with the U16. I would probably sell it and the DBX and upgrade XO to say a DCX2496. Might be an even money deal. The 2496 will give you a ton of flexibility and cure a multitude of issues that were brought to your attention. I would then go balanced XLR from U16 to 2496 and then XLR to NU3000. Easy peasy. I think you will get a nice bump in output to subs once all is dialed in but you will still need to upgrade from Peaveys subs. Pretty much any design around these parts will wipe the floor with them.
PV118 Internal Cross-over
Hi Xalanx309,
Found a picture of the internal cross-over. As suspected, just a single inductor. The picture also shows the internal wiring. To bypass the inductor just disconnect the wires from the circuit board, and connect black to black, and red to red (insulate junctions); I recommend to do this in both subwoofers.
Regards,
Hi Xalanx309,
Found a picture of the internal cross-over. As suspected, just a single inductor. The picture also shows the internal wiring. To bypass the inductor just disconnect the wires from the circuit board, and connect black to black, and red to red (insulate junctions); I recommend to do this in both subwoofers.
Regards,
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The inductor in your subs is acting as a simple 6 dB-per-octave passive Xover & is already costing you a bit of output. Adding in the dbx active Xover with a different slope & (possibly) different Xover point is gouging out even more LF frequencies. Use one or the other, but not both. Best would be the earlier suggestion of bypassing the inductor in your subs & using the dbx alone.
If you're using your subs as speaker stands (as most weekend warriors do), then most likely they are far enough apart to cancel each other at certain frequencies. Better would be to physically couple them together & find another way to get the other top box off the floor.
Again, as suggested earlier, the better configuration is one mid driver per 2 sub drivers. A 2x15 top box is usually the beginner's answer to avoiding the expense & complication of adding dedicated subs.
If you're using your subs as speaker stands (as most weekend warriors do), then most likely they are far enough apart to cancel each other at certain frequencies. Better would be to physically couple them together & find another way to get the other top box off the floor.
Again, as suggested earlier, the better configuration is one mid driver per 2 sub drivers. A 2x15 top box is usually the beginner's answer to avoiding the expense & complication of adding dedicated subs.
Xalanx309, you have PM.
Gents, chances are the amp's not running bridged. Store-bought speakOn cable isn't going to be wired the way the NU3000 needs to be wired for BTL output across 1+ and 2+.
The DBX crossover here is perfectly adequate for what's needed here - it even has highpass filters exactly where Peavey recommend the subs are cut. A digital processor might be nice, but I suspect its more complicated than is needed or wanted at this time.
Bypassing the inductor will hurt the resale value of the subs, and also you'll hear the LF amp clip more clearly, since the inductor filters the HF spikes. Think I'd leave it as-is.
Chris
Gents, chances are the amp's not running bridged. Store-bought speakOn cable isn't going to be wired the way the NU3000 needs to be wired for BTL output across 1+ and 2+.
The DBX crossover here is perfectly adequate for what's needed here - it even has highpass filters exactly where Peavey recommend the subs are cut. A digital processor might be nice, but I suspect its more complicated than is needed or wanted at this time.
Bypassing the inductor will hurt the resale value of the subs, and also you'll hear the LF amp clip more clearly, since the inductor filters the HF spikes. Think I'd leave it as-is.
Chris
Just more thoughts.
Hi Xalanx309,
Post #55: "...enclosures are absoltely trashed and the bottoms are caving in..I may sel it all and start fresh..."
That's one of the problems when using MDF as enclosure material for systems that will be moved. A decent exterior glue plywood, e.g.: baltic birch is a much better material.
You have so many options...
I've spend some time looking for the T/S parameters for the driver in the PV118, but haven't found anything yet. For other Peavey drivers-like the 1801-8, or, the 18"Low Rider-the box is too small. It might be possible to convert the inside of the box into a tapped horn or cubo-style sub; what you have there now is too small for most 18" drivers (the B&C 18TBX100 might work), and has a much too small port (as an aside: can you, please, measure the dimensions of the port opening?) for a PA sub; at resonance all of the output comes from the port, and the driver is basically motionless.
Just another thought on the subs, if you replace the single 18" w/ dual 12" in each such, you can get the sensitivity for the given volume up a bit, extend the frequency range if you want to, and by picking the right 12" you can adjust the combined speaker impedance to be optimum for your NU3000, and don't have to worry about running it bridged anymore; just run one sub per channel.
Cuppa Joe covered the inductor in Post #53. Additionally, the inductor is a coil of copper wire that increases its internal resistance with increasing temperature, so the more power you pump into your speaker the hotter the inductor, the greater the series resistance, the greater the losses... not what you want (if you google the subject you'll find that others have had problems with this particular item). That is also the reason daisy-chaining is not optimum, you are running the power for two subs through the wire(s) going to the first sub, so you will have unnecessary losses in your speaker cables. All depends on how much power you really run into your system at full level.
So many options, still, as Art said before: Have Fun!
Regards,
Hi Xalanx309,
Post #55: "...enclosures are absoltely trashed and the bottoms are caving in..I may sel it all and start fresh..."
That's one of the problems when using MDF as enclosure material for systems that will be moved. A decent exterior glue plywood, e.g.: baltic birch is a much better material.
You have so many options...
I've spend some time looking for the T/S parameters for the driver in the PV118, but haven't found anything yet. For other Peavey drivers-like the 1801-8, or, the 18"Low Rider-the box is too small. It might be possible to convert the inside of the box into a tapped horn or cubo-style sub; what you have there now is too small for most 18" drivers (the B&C 18TBX100 might work), and has a much too small port (as an aside: can you, please, measure the dimensions of the port opening?) for a PA sub; at resonance all of the output comes from the port, and the driver is basically motionless.
Just another thought on the subs, if you replace the single 18" w/ dual 12" in each such, you can get the sensitivity for the given volume up a bit, extend the frequency range if you want to, and by picking the right 12" you can adjust the combined speaker impedance to be optimum for your NU3000, and don't have to worry about running it bridged anymore; just run one sub per channel.
Cuppa Joe covered the inductor in Post #53. Additionally, the inductor is a coil of copper wire that increases its internal resistance with increasing temperature, so the more power you pump into your speaker the hotter the inductor, the greater the series resistance, the greater the losses... not what you want (if you google the subject you'll find that others have had problems with this particular item). That is also the reason daisy-chaining is not optimum, you are running the power for two subs through the wire(s) going to the first sub, so you will have unnecessary losses in your speaker cables. All depends on how much power you really run into your system at full level.
So many options, still, as Art said before: Have Fun!
Regards,
Agree with chris661 on the first two points. Probably store bought SpeakON which is plugged into 1+ 1- on the amp and not 2+ 1+. Getting that taken care of will quadruple the power available on tap. That does mean roasting the subs is more of a concern, but that will come down to OP's good judgement.
I will disagree on the inductor. I feel like it's kindof a bare-minimum filter Peavey puts in for the people who don't know better and will inevitably put a full-range signal in. If you have a proper active crossover, I'd bypass it (and reconnect if you want to sell later). If the sub is bridged, I think the woofer will run out of excursion before the amp clips offensively. Meaning it's mostly a parasitic load.
I will disagree on the inductor. I feel like it's kindof a bare-minimum filter Peavey puts in for the people who don't know better and will inevitably put a full-range signal in. If you have a proper active crossover, I'd bypass it (and reconnect if you want to sell later). If the sub is bridged, I think the woofer will run out of excursion before the amp clips offensively. Meaning it's mostly a parasitic load.
Considering the entry level nature, age, and condition of the cabinets, disconnecting the inductors would have no effect on their resale value. The inductors probably could be sold separately for a fair portion of what the used subs will bring- copper is forever, but the OP's speaker cabinet's "sell by" date has long past.
On the flip side, there are loads of good deals on better cabinets available at flea markets and Craigs list- I almost bought a $600 15" sub with 30mm Xmax that was going for $250 with a well made cabinet, but it weighed a ton, and the guy never returned my e-mail.
Recently bought a SWR "Henry the 8X8" with 7 working Celestion BG8-60 woofers (surrounds still look brand new) & a LeSon tweeter, and a Hartke 2x15" with a pair of VLF1508 & a rather nice CD34T compression driver/horn, all for $120!
Art
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