Saba ,
Such a good deal!! definitely make sure to get the ones you want before announcing the source, it seems like we have been through that
Hopefully it wasn't a bad recone job on that refurbished driver that is causing your buzzing sounds ... If the NL4 is leaking that should be fairly easy to fix i would think ....You would think those things would be more airtight ....
Sorry your DJ friend wasnt able to take those single drivers boxes off of your hands , i would say just sell them on here but im sure the shipping would be ghastly ...
Saba ,
Such a good deal!! definitely make sure to get the ones you want before announcing the source, it seems like we have been through that
Hopefully it wasn't a bad recone job on that refurbished driver that is causing your buzzing sounds ... If the NL4 is leaking that should be fairly easy to fix i would think ....You would think those things would be more airtight ....
Sorry your DJ friend wasnt able to take those single drivers boxes off of your hands , i would say just sell them on here but im sure the shipping would be ghastly ...
The NL4 has been significantly hot glued/attemptedtoseal. Will pull our the tubing tomorrow. Hopefully I'll have an answer to the mechanical noise as well. I used the 10 inch alpine with no issues (mechanical noise) so I assumed this should be similar...
Potential glue failure on the driver, so epoxy-ed that in, will test after a few hours of curing. (tested problem driver free air, same problem. Other driver has considerably less weird noise but still a little bit -- will diagnose later. Small airleak on right speakon, need new ones as these don't conduct with the amount of glue I had to apply.
Glued driver cone, flipped it around (driver in throat). Having severe frequency response issues. Doesn't play below 38 Hz like at all, should be down at 32 Hz in corner... Yes I've varied placement...
Measurements will come.
Behaves a lot like a 42 Hz tune instead of 38.
Driving one driver at the moment, other is just there to seal the cavity until I figure out a wiring situation for the second driver inside the cab.
Measurements will come.
Behaves a lot like a 42 Hz tune instead of 38.
Driving one driver at the moment, other is just there to seal the cavity until I figure out a wiring situation for the second driver inside the cab.
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Also, I can drive it to audible excursion limit with less than 300 watts (not clipping the gx3) into one driver... hmmm...
It's really bad... No detectable leaks at the moment.
It's really bad... No detectable leaks at the moment.
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Measurement done in middle of room measured in extreme nearfield. Tested T60 (same electronics setup, my reference sub which still measures pretty flat) and it backed up what my ears were telling me --> the really peaky measurement was actually what it, this 2x12 sounded like 🙁
Ok much better once I wire up 2nd driver. This is response after some EQ vs no EQ. It's evident which is which.
Driver still doesn't like medium-> High excursion. Clearly hitting something, either in the motor or a wall.
Driver still doesn't like medium-> High excursion. Clearly hitting something, either in the motor or a wall.
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Subjectively, it sounds great in SQ now that I've turned the driver around, fixed the slightly leaky speakon, and EQ'ed it to taste. However, once it starts slapping something, I've watched the excursion and it is maybe 10-15 cm P2p at this point. Haven't pulled out the far driver, maybe that isn't seated quite in the right spot. In room with the EQ bump I gave it I can hear all the notes in songs even 29 Hz tyga. I have a 29 Hz HP at the moment and given 3 dB of room gain around 30 + EQ = almost flat to 30.
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Saba ,
Such a good deal!! definitely make sure to get the ones you want before announcing the source, it seems like we have been through that
Hopefully it wasn't a bad recone job on that refurbished driver that is causing your buzzing sounds ... If the NL4 is leaking that should be fairly easy to fix i would think ....You would think those things would be more airtight ....
Sorry your DJ friend wasnt able to take those single drivers boxes off of your hands , i would say just sell them on here but im sure the shipping would be ghastly ...
Going to take the farther driver out tomorrow. Free air test that one, see if it makes the noise disregarding the box, to rule out rub on side wood.
I was going to say that since you were just trying to use just one driver temporarily that you could short the connections (voicecoil) on the other driver to stiffen it up but the output would still be terribly underdamped and with too much cone flapping ..... Now that you are using both drivers you can see that you are getting more damping and a broader response .. still not quite ideal though .. .
If you want to know what the true FB (tuning) of your box ended up being there are a couple of easy ways to see where you impedance minimum is ... You can use a resistor and an AC voltmeter or even a lightbulb used in series (along with you amp & signal generator) to test it ! ... It is possible that your FB is slightly high if the path length wasn't estimated quite right ...
Have you confirmed that the buzzing is driver mechanical noise or something else?
driver buzzing sound seems to be mechanical noise. the "bottoming noise" has yet to be confirmed, need to pull out 2nd driver for. FB seems to be on point or close to it.
Good news, and bad news, good news is I figured out the problem. Now for the bad news: pulled both drivers out to do a free air test and the "new" driver I had bought was apparently damaged before I got it, long excursion makes a really nasty tone. Let's see if alpine will replace it.
So the refurb turned out to be good, and the "new" driver turned out to be faulty?
Filed a claim about the faulty driver, within the day got a response from the seller 🙂 refund en route. Ordered second refurb driver 🙂 from the other company that packed it in double box + peanuts.
Yes, that's what happened. (I have always had better luck with refurb than "new" because it means they have tested it!)
P.S. the 2nd refurb driver I just bought is the cheapest one I've gotten to date at 59.99 free shipping no tax. Now that's a deal.
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Update, it plays now, but seem to have run into an issue, push pull seems to create turbulence with the driver who's magnet is in the throat. Makes a really weird noise akin to wires rattling superset with air turbulence which only occurs with low frequency high velocity content. Yes I tested the new driver in free air, it checks out.
Significant amount of room rattle as well, could be that. Have to do an outside test!
Significant amount of room rattle as well, could be that. Have to do an outside test!
Almost forgot: It sounds darn good, only seems to give up with large amounts of <35. The excursion minimum seems spot on and for the ever important 35-55 region the output is insane. What's really nice is that even though I have a 500 watt (into 4 ohms) amplifier the impedance spike of the box means that only 350-400 watts are required at "50 V" and thus I won't really be amp limited unless there is significant content right around 32 and 75ish Hz. I have yet to see the clipping light engage, even when pushing it to what seemed to be xmax at times. Just set up my voltage limit to 45 so I can be extra safe. It should be fine at 60 V once I have an amp that can reliable deliver 1000 watts. I hardly think that would be necessary unless outside as this thing is darn loud as is.
Question: Should I flip the driver out of the throat to avoid high velocity turbulence and give up the push pull or just live with a little mess extreme (30 Hz i.e. below the intended passband). It sounds very clean as is (compared to things I've heard, distortion test will come later).
Question: Should I flip the driver out of the throat to avoid high velocity turbulence and give up the push pull or just live with a little mess extreme (30 Hz i.e. below the intended passband). It sounds very clean as is (compared to things I've heard, distortion test will come later).
My money says it will drive you nuts until you flip it and see what happens.
Weird, flipped polarity and it barely changed anything (one of the drivers internally). Also, larger than expected roll off at 70+ that doesn't really come back up like in simulation. Fixed with a bit of eq but startling.
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