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peniku8

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Posts posted by peniku8

  1. 1 hour ago, SME said:

    I would not recommend PEQ boost of any kind at 30 Hz.  The vent tune will already be contributing to ringing there, and any boost, no matter the bandwidth, will likely accentuate that ringing.  If instead of cutting from the top, one wishes to boost the bottom, I'd suggest trying a low-shelf filter if that's available.  A low-shelf centered around 75 Hz  (looking again at the sims) could be helpful.  However, I think the PEQ I suggested above may be a better place to start.

    That would've been something around

    F30 +2db Q0.6

    I doubt that you'd notice much ringing with a filter like that, but you're correct of course. Also, I think modern processing equipment should be accurate enough to reduce rining to a minimum. There are mixing consoles that have up to like 48bit 192khz processing. Mixing desks are not loudspeaker management systems, but I'm sure these are also up to modern standards.

    1 hour ago, jay michael said:

    Ok thanks for the suggestions. Next time I have it up and running ill tame that peak at 200 a bit.  I had the subs pretty close to my fence this time so perhaps that's what was happening around 85.  Agreed fully on increasing the sub output.  I kept it flat-ish to not completely drive my neighborhood nuts.  In your opinion which is the better way to do this?  Reading the manual for my venu360 dbx seems to suggest I should turn down the attenuators  on my amp powering the Danleys until the desired top vs sub balance is achieved.  I have read from other sources to just boost eq for the range controlling the subs.

    I'd prefer having the subs and tops at the same volume at the crossover frequency (you can easily measure that by sending them a sine wave at that frequency and measuring the SPL of the speakers individually), then applying an EQ to shape the response of the entire system. You can experiment with different low shelves. On my home system I have the sub some 9-10db hot and have a low shelf of +6db 30Hz Q0.7 on top of that. PA systems often start rising up to like 10db from 1khz down to 100hz and some more in the sub region. At least that's what I've seen in an l.acoustics paper.

  2. This Article is the HiFi version of this:
    https://joeysturgistones.com/blogs/learn/why-your-studio-doesn-t-need-a-subwoofer

    A very well respected studio engineer, known for mixing big Metalcore acts, such as Asking Alexandria.

    And I'm sure the causes for writing such an article are the same in both cases: bad integration which lead to the descision of discarding subwoofers entirely.
    Those are the people who cause the necessity for BEQ, by just filtering out the low-end which their system can't reproduce.

  3. I'd put a broad PEQ at 30Hz to bring that up to equal the 70Hz SPL (or bring down the 60Hz alternatively). The 85Hz notch might need some experimentation, it may or may not be good trying to even that out. It is so narrow so you might not even notice a difference. I found that positive EQ'ing with a very high Q often doesn't provide any desirable changes.

    When EQ'ing out phase problems I encountered a very wierd pumping phenomenon once. When playing back a sine wave, the level would sway, as if it was controlled by some kind of LFO.

    You can't recover the 150Hz dip as that it caused by internal phase cancellations. More energy also means more cancellation so you end up without any improvements.

  4. 24 minutes ago, medico said:

    Very interested in this design, going to build one just to have a listen. and if i like what i hear i'll build 8+ of them for our rig!

     

    one thing, our tops are bit wider than these, so would want to build them 2inch or so wider, and possibly taller, by few inches.

    will this effect the sound in anyway? and how so?

     

    also whats the best way to do so? scale everything up?

     

    look forwards to hearing back!

    Cheers, 

    Murdoch

    Scaling it up would drop the tuning quite a bit. Making the cab only wider wouldn't make much of a difference, but if you also increased the height you'll end up with a pretty big spike around 30Hz so you'd want to EQ that out. Here is a response with the wider cab (guesswork):

    wJOb9Qw.png

  5. 1 hour ago, Timon said:

     

    before we start building the second skram we want to make oszillating tests with test pieces. These will be like 18mm birch, 12/15mm Banova with Epoxy(and carbon), the same with  poplar and birch. we are not sure zet, how the tests will look like, but we are sure to find a way ;) after that we will make the second skram out of the winner design and then compare it with the orig. skram.

     

     

    Ok, those are interesting advices, so we will try it without them first.  Is it a good idea to make i.e. per side one Top with both, the AMT with the Mids, and a second cab with only the Mids (eighter with the same tuning or again as a 4 way system?)

    Another change in the plan is to use not the very expensive wavecore driver, but instead something like the http://www.precision-devices.com/Product-Details/PD103NR1.
    Would you recommend a closed box or BR Design for a tuning around 100Hz? (And could you recommend a calculation tool for designing these?)


    We want to use a FP10000Q for two skrams, another class A/B or D amp for the L/R mids and one for the L/R AMTs.
    Do you prefer a single extern dsp for all amps or the build in dsp (with much more effort)?
     


    Thanks a lot for your help, I think we are on a good way! :)

     

    You'd want the tuning frequency of the mains to be way below your Xover freq, due to the phase swap at the tuning frequency (that will cause cancellations with the sub).

    I'd advise on going with a ~70Hz tuning frequency (or lower if possible) when going with a 100Hz crossover at 24db/octave or greater, that would leave you with half an octave of constructive interference. I would also not cross over that PD driver at much higher than 2k to the tweeter.
    I prefer using networked dsp amps. That way you have quick access to all your amp channels and settings from your PC, which allows for efficient system tuning.

    When using the FP10kQ for two subs, either use it in bridged config (with 8Ohm drivers) or one cab on channel A and one on channel B to prevent bus pumping.

    Depending on how big the dance floor (?) is, it might be advisable to put two cabs low and hang two up high, so you can individually adjust the SPL of the tops to get an even coverage.

  6. Another thing that confuses me is the fact that you did use the lossy inductance setting, but did not use the additional parameters you measured, or am I confusing things now?

    When I enter values there and turn them on, the Le will light up in green. The SKHorn measurement looks closest to the simulation without these parameters (Le in red), so should I model my design (using the IPALs atm) with Le in red?

    I'm trying to understand this setting, am I correct in saying that lossy inductance kinda does what the shorting ring is doing in the driver?

  7. 4 hours ago, Timon said:

    Hey guys,

    my friends and I are totally fascinated of the Skram and for now we want to build two of them. 
    At first we'll build it with the suggestion of 18mm birch ply and after we want to do some changes for the second pair.
    We want to make it out of 15mm (birch ply and in the core of it one layer of poplar to make it lighter) in addition we would like to add some braces out of carbon and epoxy resin. It should be as stiff as 18mm birch ply.

    Do you have any concerns with this plan so far? 
     

    We are not sure which kickbass we want to use. Maybe some of you have another recommendation?

    We are planing to build one Cubo Kick 12 per Skram with the 18sound 12ND830 and a little bigger cabinet, so it gets down to about 90hz and up to 200hz.

    The other consideration is to build some sealed boxes as kicks but I worry if this will be very harmonic with the Skram. But it should be the purest and punshiest kick, isn't it?
    There would be I guess 2 drivers per Skram (depends on the driver). 

    What do you think? What would you do?

    As Mid Tops (from 200hz with a bit different AMT) there will be one Mundorf AMT (with a horn in front of it and an active cooling system) and two Wavecore WF259PA01 per side.. Mostly we are playing Techno, etc. but the system should be able to let you enjoy all kinds of music...

    It would be great if you guys could help us with your knowledge!

    Thanks a lot,
    Timon

    I would advise against the combination of hardwood and plywood, as both have a different CLTE. If you're really limited on weight, you may try to use Banova Ply. You could do the outside panels with regular BB ply and use the Banova for all inside panels (and be my guinea pig at the same time 😉)

    Other than that, I'd personally prefer to keep the speaker count at 2 (i.e. one or multiples of the same sub playing from 20/30Hz to 60/100Hz depending on taste and a (line) array of the same capable tops). I had a quick look at the tops you're using and I don't see the need for a kick bin here. The dual 10" tops should capable enought to cross them over between 80 and 100Hz, and the Skrams are capable enough to be used in that configuration as well.

  8. On 2/20/2018 at 10:10 PM, Ricci said:

    Incorporating the air volume in the driver cones rather into S2, instead of using Vtc and Atc, was a much closer match for this design.

    I got into HR today and finally understand why you chose to correct the parameters like this. How much of a difference did this make?

  9. 5 hours ago, Ricci said:

    NSW6021-6 looks great in either the Skhorn or Skram. No mods needed. Same for the SAN214.50. If you want a larger back chamber use the Skram. 

    That's cool, I was thinking about boosting the bottom end (via a larget back chamber?) to get a flatter FR. Or would multiples (open air) do the trick similar than horn stacking? I know you get the biggest benefits by making a cluster, but I'm not a fan of that. I'd either go with one per side for smaller shows or a row of 4/6/8 along the stage front. Ya know, beamforming n stuff

    I mixed a show for around 1600 guests a while ago and there was a center bass cluster of 4 SB218. When mixing so that the FOH had a decent bass level 20m from the stage, the first row near the subs was in for a hell of a ride. When hearing complaints about the kickdrum, my question 'where did you stand?' was always answered by 'right in front of the stage'. I don't wanna do that when I'm in charge of the PA.

  10. @Ricci, how do you expect the new Eminence driver to perform in the SKHorn? Its stats looks pretty close to the IPAL, with the benefit of being a good fit for 2Ohm stable amps (with 3Ohm per Cab per channel), but the efficiency might be a little lower?

    Since the LaVoce dropped in price here (to 350€/400$, can probably get it even cheaper) it would also be interesting how one would modify the cab to fit that driver better (slightly larger back chamber?).

  11. On 2/10/2019 at 8:58 AM, SME said:

    I'm curious as to what you were thinking of.  One dead simple idea is to just take the double driver Skhorn, cut it in half and add a 3/4" wall where the center used to be along with maybe some extra bracing.

     I think the hard part would be finding what kind of binding hardware works best.  Something ratcheting might be a good idea.  Maybe nylon strip like for tying down loads?  Ideas...

    I don't have enough knowledge about designing horns to be talking about this with confidence, but since the horn opening angle would drop to 6° from 12° if simply cut in half and adding a side panel the interior would need to be redesigned. That is if a horn works the way I think it does, if it doesn't please call me out.

    As for binding hardware butterfly latches would be great. I actually posted about this modular cab idea using butterflies on AVS some time ago but nobody seemed to be into it.

    You could even saw the original SKHorn in half and slap like 6 butterfly latches on that to combine it. Use weather stripping to seal it and you have your modular SKHorn.
    I wonder what it would sound like if just left in pieces  :D

    But I think we're going slightly off topic here, that could be discussed in a new thread ;)

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