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  1. Yesterday
  2. Kyle

    Eminence NSW6021-6

    I tend to think its a glue problem, or primer problem.
  3. peniku8

    Rob's Amp tests

    I ordered two replacement modules, will see if the current ones are the same. This amp is 7 years old after all.
  4. The 1kv to ground sounds very weird as even if the heatsink was live on purpose you wouldn't expect 1kV to be generated anywhere in the amp. Mix of output transistors is a very bad idea as they won't share current effectively. On the plus side this is making me very certain I don't want one of these amps in my life
  5. ErnieM

    Eminence NSW6021-6

    Yes, that was the one. We'll see how the fixed drivers compare with the two good ones I have. I wonder if it's more common on these high xmax accordion surround drivers.
  6. Last week
  7. Yes, it happened to me with B&C drivers . You will find my video on YouTube
  8. Yea I returned it. With the phase plug I was just refering to the general direction. I had 12 woofers in series and it was clear that this one made noise well before reaching Xmax and it was about 5db earlier compared to the other woofers.
  9. Kyle

    Eminence NSW6021-6

    Hard to tell what that might be, best to return it if you can? The noise may be coming from the motor or voice coil. The phase plug won't likely be making any actual noise itself, but any number of things could be wrong with that driver, its very hard to tell sometimes what exactly it is.
  10. Kyle

    Eminence NSW6021-6

    Any small issue with glue or primor can lead to failure. Its a bit tricky and takes precision. Hopefully Eminence can get those fixed for you
  11. peniku8

    Rob's Amp tests

    This is so annoying. I was just way too curious to see if I could improve the amp's performance by adding those components and now I caused 150$ damage again. Well, heres more random info on the PSU: when both amp stages are disconnected, the PSU hold over 200V for an hour. I used a light bulb to quickly drain it. When it's down to 0.1V, it takes about 10 seconds to climb back to 2V. I immediately connected the 230V light bulb after I powered the amp off, when the PSU was still at around 350V from positive to negative. It was a 30W light bulb or smth, it lit up brightly for a second and the light faded completely after some 20 seconds. Very convenient way when you're working on this kind of stuff.
  12. peniku8

    Rob's Amp tests

    Seems like this amp is haunted by Hoffmann's Law. I'm not sure why but the modifications I made (wich was adding the two missing resistors and transistors) broke the amp stage. The fuses melted so I removed the components again but it's still inoperational. Welp, now the amp doesn't work at all anymore, since both output stages are broken. I'm guessing that it's a relatively minor thing, but I'm not the one to track down a broken component and I'm fairly certain that getting it fixed will be more expensive than the 150$ for the replacement board.
  13. peniku8

    Rob's Amp tests

    What confused me even more was the seemingly random choice of output transistors, as two different models were actually used in the amp. One output channel has an even distribution of both types, while the other one has 5 of one type and 9 of the other. Both are the NPN type. https://www.onsemi.com/pub/Collateral/NJW0281-D.PDF https://www.onsemi.com/pub/Collateral/NJW21193-D.PDF Looks like the 21193 is a bit better. I'll solder two from the broken pcb to the working pcb to "upgrade" the FP-13000 to Fp-14000 on the output stage. It might make a slight difference into lower impedances. 14 vs 16 transistors is still a decent upgrade.
  14. peniku8

    Rob's Amp tests

    I somehow feel like this is bad design or something isn't working as it should. The 4 transistors I replaced in the PSU, which all broke after about 2 minutes of 4KW output generate a humongous amount of heat even in idle. The heatsink seen below reaches 80°C (176°F) in idle and SOMEHOW I measure over 1KV from heatsink to ground and when I touch it with the thermo sensor I see small sparks. What is going on here??
  15. Earlier
  16. Interesting, I also had a problem with one of the 14 Dayton woofers I recently got. Very similar noise, just that I was testing at 20Hz so the "clicking" was slower. The issue doesn't seem to come from the surround on the Daytons, more like the noise comes from the phase plug (those woofers have a solid phase plug in the center instead of a dust cap).
  17. ErnieM

    Eminence NSW6021-6

    Thanks! These are new drivers. First test was all drivers wired in free air with a 20hz tone. Stood out immediately even at low levels....which means it was either missed in QC or shipping loosened something up. Kind of wish they (all) went with a suspended inner box with foam edges for shipment. Heavy drivers go on a rough ride. Eminence emailed shipping labels today for two of them. The quieter one wasn't too bad but I imagine it could get worse with time. Hope they turn out out well in the long run.
  18. Kyle

    Eminence NSW6021-6

    Welcome! Are these new drivers or did they fail after some time?
  19. Hello Sir Ricci,

     

    What are your thoughts on the new Dayton Audios 21 inch sub?

    Do you think it would be a good fit for either the SKHORN or SKRAM?

     

    https://www.parts-express.com/dayton-audio-pss555-8-21-pro-subwoofer-with-45”-voice-coil-8-ohm--295-050

  20. ErnieM

    Eminence NSW6021-6

    https://drive.google.com/file/d/1-fUDVjQIgSk6yMSriJNTysL_wo4IN-vJ/view?usp=drive_web Surround isn't glued perfectly to the frame as I can decrease the noise by putting pressure between the outer roll and gasket. This is the worst out of four. Two are fine, one is very slight, and this one is noisy. The low frequency noise is clipping in the signal. Seems this was an issue with several drivers from other manufactures as well.
  21. Have some miniDsp for EQ; my goal is to achieve about 130db at 20 and 120db at 10hz in room.Do you think it’s possible with 6 sealed Ultimax and 4 sealed Magnums? What do you think is the ideal enclosure volume for the ultimax?(I’m not familiar with winISD yet) Want to put the Magnums right beside the Ultimax when sealed.Here is a pic with the actual setup.
  22. Are you using some kind of EQ (manual or auto) right now? Do you have any idea how much output you need vs. what you have in the deep bass? Switching to sealed will give up a lot of it, and you might want to use some EQ to bring response up, at the cost of more headroom. The other issue will be the integration complexity, especially if the Magnums-12s are ported, as noted in earlier posts. Will all the different subs be placed close to one another? That definitely makes it easier. Will sealed vs. vented Magnum 12s give you enough output? If so, this will give you the most flexibility with respect to crossover.
  23. Have three inukes6000 dsp, one channel for each driver.I will take some more measurements with rew to see what happened.It can still be a room issue to, but since I installed the huge absorber on the back wall the standing waves are diminished pretty much.I always felt that the ported boxes sound boomy sometimes in my room; is a sealed cab gone to sound different in room then the ported box? for budget reasons,can’t sell the um-18 and go with another driver, just modify the ported and make smaller sealed boxes to have space to accommodate the Magnums-12 to take care for the midbass.Do you think that approximately 7 cft exterior volume is ok fot the Ultimax in sealed enclosure?
  24. Ported subs are easy to integrate if they are the lowest playing speakers in the system. If you have ported subs and want to run something below that (like sealed or other deeper ported subs), you'll have a hard time on doing so. FIR filtering might be the only solution, at the cost of delay and ringing. But since that's not the case you won't have to worry about that.
  25. I can’t switch the drivers no more, I will stay with the um’s and the Magnums, that are pretty sensitive drivers and give it a shot; I hope to integrate them with the Um’s and split the frequency range in two, say 5-50Hz to the Um’s and 50-120Hz to the Magnums.
  26. Could be room issues. Its pretty easy to stuff your ports and get a sense of what a sealed box sounds like. The larger box volume won't negatively affect the midbass at all. Only really increases efficiency down low. Just make sure to turn off your high pass filter once you seal it... and go easy at first! But what you really might just need it to figure out if you have some standing waves in that room that negatively affect the bass. Just move the subs and see what happens. I would also consider getting a higher efficiency 18" driver and just switching that. But before doing anything costly, what sort of power are you running to your subwoofers?
  27. You might wanna ask this question on AVS again, but unless your cab is severely mistuned, the issues you‘re hearing are likely room issues. I have no experience with the um-18, but apparently it‘s also pretty capable in the mid-bass region. I‘m not sure if dropping those drivers in sealed cabs would yield your desired improvements. I have seen other people using (multiple) um-18s seeking for better misbass performance, which makes me wonder why not go for the 21ds115 or similar instead. I know in the states they‘re similarly priced and you‘ll lose a bit of deep bass (displacement), but you‘ll gain a lot of sensitivity. If those magnum drivers are high sensitivity drivers, I‘d give them a shot. Should work rather nicely in sealed cabs. What other subs are you using in your setup, for which you‘re hoping for better integration?
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