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peniku8

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Posts posted by peniku8

  1. 44 minutes ago, kipman725 said:

    I do some PA stuff on an amateur basis, my tops are ~100 dB/1W and I run them off 4 amp channels rated as 120W (180W peak) per channel.  On some drum and bass I have seen the clip lights flicker on the power amps would I be correct in estimating that would be about 110dB peaks and an average around 100dB at 3m from the speakers?   Also what kind of instrumentation should I get to monitor SPL? as sometimes I worry that its too loud as it can be hard to tell as distortion is low. 

    If your 4 tops are clustered that would make around 133db at 1m at 128W into each top (double the power equals ~3db gain, having twice the speakers makes ~6db gain if perfectly aligned). You can substract 5-6db per doubling of distance if the tops don't have an exceptionally narrow throw (like line arrays) so it should be about 8db less at 3m. Maybe the effect is less grave at close range thou since humidity doesn't come much into play at short distances, so it could be even louder.

    For SPL measurement I use my iPhone, which was calibrated with a UMIK. Factory settings were (only?) like 2db off in the "Mobile Tools" app I'm using.

  2. I've mixed shows where the PA with only vocals on it could hardly keep up with the dumkit in the room. I'm talking 120dbA here, room for 150 people. No acoustic treatment, often not even half full. Hardcore drummers with a Snare drum forged on Mt. Doom.

    I don't mind a little stage bleed in mid-sized venues, as it usually just results in a 1-4khz boost in the cymbal range. That's what we can bring cympads for if it gets out of hand, but at some point it's just too much. It's all about optimizing the sound at the FOH and you have to find the right balance.

    And if you have issues playing a little less loud (ofc I wouldn't expect anyone to reduce his Metal drumming to conversation volume) you just need to practice more. I've been playing the drums in an Orchestra for 15 years now, that's where you really learn to control your dynamics. On the other side I'm also playing live shows with my Deathcore band and mix engineers often wonder why I'm playing so quietly heh.

    The 100dbA I was talking about was during the songs with 3s average. Long term average over an entire show (Swiss, Z7, 1200 guests, huge venue) was 95dbA. It was a Punk show, so pretty low crest factor stuff. I was told to stay under 100dbA long term average and was a little intimidated by the main guy telling me that he'd turn the PA off if I exceeded that. He turned out to be a really nice guy thou and told me a story where some guy started a show with 10 minutes of 120dbA average and he just shut the entire thing down. Some people really seem to lose their mind on the mixing desk.

    A friend recently had problems with loudness measurements at an outdoor event, where he saw the volume exceeding 120db periodically in the logs and they just couldn't figure out what happened. After some investigation it turned out to be freight trains passing by. Great choice of mic placement

    • Like 1
  3. 120db was unweighted or dbC. You wouldn't enjoy a concert at 120dbA. When I mix shows outdoors or indoors in a venue with a capacity of say 500 and up I like to keep the dbA average at 100, because that's where it 'excites' you but it still doesn't hurt. That also happens to be the European standard and limit/goal for Rock concerts usually. When observing the db meter I noticed that some crowds (cheering of 1000 people and more) easily exceeded 100dbA.

    When mixing shows in smaller clubs you'll notice that the un-mic'd drumkit already exceeds 100dbA and you're left hoping for the drummer to accept your request for playing quieter or you can't really mix. Legally, you'd have to end the gig halfway through, because the band was 'using up' their loudness units too quickly.

    I've got two smaller shows in Austria next month, I'll have a look what dbZ I'm usually reaching, but my guess it that it's gonna be around 115db-120db while the kick drum is playing.

    • Like 1
  4. I've recieved the two 4 Ohm 21DS115's today and I can't help but feel that they have a bigger magnet than their 8 Ohm siblings. I'm too lazy too move the SKHorn and open it up to have a look at the 8 Ohm drivers in there; does anybody else own both versions of the driver and noticed a difference?

    The only obvious difference was that one came with the fast-on/solder terminal and the other with spring loaded binding posts.

  5. @Ricci I got some time to test the interface today and found just a single PC Oscilloscope software that was able to use the audio input as input device. It is a little cumbersome to use and not very feature-rich, but offers what I need. The meter on the interface is a true RMS meter but gets a little wonky below 20Hz. I tested my amp and it started limiting at 132V RMS, which is about 187V peak. Voltage peak limiter was set to 190V, interesting!

    The software should work just as well with the other attenuation box mentioned, but with that one you won't be able to do ultra clean low level measurements.

     

    vh7Nqq8.jpg

     

    OeNvISt.jpg

  6. Btw I posted the Skhorn driver comparison to the Skhorn thread. Skram should be similar (in terms of differences between drivers). Noteworthy is that the cheaper drivers all offer the same headroom, the Eminence more bottom end headroom and the IPAL more overall headroom. IPAL is above the Eminence at all frequencies, the difference ranged from a fraction of a db to like 3db around 80Hz iirc. 

    I also just ordered two more 21DS115, but I won't be building Skrams, or I could post some measurements. I'm currently more interested in my own design, which models just to my liking (Skram is too big).

    • Like 1
  7. 6 minutes ago, klipsch said:

    So many driver choices. Great news! 

    Sure would be nice to have a comparison of each in one set of graphs :)

    Since Ricci didn't measure the SKRam cab yet, the data isn't as perfect as the SKHorn's. I can could these graphs for the latter thou. At least with the most popular half a dozen. I won't include all the RCF and 18sound ones, that would just be TMI for an overlay

  8. 26 minutes ago, SME said:

    Yes.

    I must have missed something.  Is there a 2 ohm IPAL?  Anyway, the NSW6021 should be easier to drive with common amps.

    Yes there is, it's just not public. The stats are a little worse compared to the 1 Ohm thou. You can only get the 2 Ohm IPAL as commercial customer I guess

  9. @droogne when you double click the Le input, a small window appears where you can enter the complex inductance parameters. When you turn those on, 'Le' will turn green to indicate that you're simulating with CI. I have set up my driver files to automatically load these for maximum convenience; I can attach the files here if needed.

    I overlayed the graphs with Photoshop.

    The street price on the Eminence looks to be still almost twice the price of the LaVoce, plus it's very heavy. It gets within .5db of the IPAL thou, so basically equal to the 2Ohm IPAL I guess.

  10. @SME Check out iZotope's Ozone Exciter. It's basically the plugin that you're describing. It simulates different types of tube, tape and other distortion. It's just the nice type of distortion which is called saturation nowadays. It is very powerful but also very resource hungry, a few instances of it in a mix already max out my 4 core Xeon CPU.

    I feel the same about mp3. People with inferior knowledge talk down on mp3 because they just know the early stages of Fraunhofer or have only heard 128kbps files. In fact, when doing it properly (with VBR lame, slow encoding) you can make 128k mp3 almost transparent on most speakers/files. I listen to metal mostly, which is basically the worst case scenario for any compression algorithm (broad spectral content, low crest factor), and all of the files on my phone are converted to 140k VBR with my favourite audio converter dbPoweramp. If you convert from a very good source, that will be transparent on any usual pair of headphones with a given ambient noise around you.

    I was only able to identify 2/3 of the wav vs 320k files in a DBT correctly, but I'm eager to try this again when I built my new speakers with Ribbon tweeters. 

  11. @droogne that's a lot to reply to, I hope I manage to catch everything posting from my phone.

    The 2nd graph I posted shows the maximum output of the cab/driver combination which is either Xmax limited or power limited (depending on frequencies).

    I killed the colours for the B&C drivers, but the LaVoce graph line is two colours: green for power limited and red for excursion limited. You'll see that the graph is red from 0 to 29Hz and green from 29 to 38Hz. That correlates to the excursion minimum at the tuning frequency, so the driver hits its power limit before it hits Xmax at this frequency band in that cab.

    If your system hits Xmax with 50% power at a certain frequency that's okay. Unless you're running heavy limiting, program material will not contain 0dbFS sine waves. When you're far away from excursion limits using the rated AES power, it is likely that your cab is too small.

    As you can see in my comparison, the IPAL is about 3db ahead both in the power limited as in the excursion limited bands. I don't know how you're getting your 6db difference, but it doesn't seem correct to me, no matter the cab. How are you determining the headroom?

  12. @Droogne I don't know how you're getting to these numbers, but 3-4db difference between the SAN214.50 and the 21SW152 sounds like you're comparing them using the same voltages while using the 4Ohm version of the SW.

    Here is a model of one of my designs at 1Watt into Znom, black line is LaVoce, grey the B&C:

    HszrHvR.jpg

     

    Here is the max output graph (at their rated AES power, basically an excursion limited efficiency graph), LaVoce in green, SW in blue and 21IPAL in pink.

    CZzVfg6.jpg

     

    Also, 650€ for the 21IPAL is a very good price, could you paste a link to that supplier? That's like the regular street price for the 18IPAL here

     

    Edit: all models used Josh's complex inductance parameters

  13. Price difference between SW and DS seems heavily in favour of the DS considering that the drivers are basically just a bit different. I mean, you won't gain any notable headroom by choosing one over the other. SW is 520$ if you buy 4 or more, DS is 420$ for 2 or more from where I can get them. I guess the prices are similar in the states when on discount?

    I've seen the LaVoce for 380$ on PE, so that's anyother even cheaper alternative. And the LaVoce models a bit differently, which can be great depending on the cab you're using. It doesn't show the bump in the 60-70Hz region which I sometimes see from the DS.

  14. 7 hours ago, dgage said:

    Maybe your film composer buddy could ask some of the audio engineers that finalize the soundtrack to speak to some of the things we find when reviewing movie soundtracks, especially some of the filtering that appears to get applied.  I’d be interested if they could speak to what is being done (software, plugin?) and why.  And then a way to reach out to that community so we can nicely ask them to stop putting out neutered soundtracks.  One could wish. :)

    I'll see how much information I can sweep up, but I can tell you that a fixed HPF is present on almost every mic-pre nowadays and it is very often being used. When it comes to plugins, you almost always see Waves plugins being used. I could also imagine that removing ULF could be a part of de-noising. That is typically done in iZotope RX, which I own but have not used yet, so I can't tell if that is happening there.

    What I think is most likely is that the HPFs are baked into the SFX files directly, which also explains why you sometimes see a graph that looks like several different low shelves were cascaded (the result of stacking effects with different HPF points). I should go through some of my sample packs and see if these come with a HPF in place right from the store.

    • Like 1
  15. 4 hours ago, dgage said:

    But why neuter the sound below 25 Hz unnecessarily?  If a system can’t play that low, it’s just like systems that can’t play to 20,000 Hz, no big deal.  But once they start putting these canned filters in the bass, they’re negatively affecting the soundtrack for no good reason.  I wonder how many would cry if they started rolling off the top end at 18,000 Hz.  Oh well, 

     

    I was about to write, I wish I knew how to get through to these soundtrack engineers and then I thought about them having a trade group or society.  Does anyone know what group the soundtrack engineers might be members of?

    I only know one film composer and he said he'd "stay away as far as possible from social media" since it would be consuming way too much of his time 😄

    I'm more active in the music production business thou, so I don't have much insight on movie production

  16. 6 hours ago, Ricci said:

    Excellent...I may have to buy one of these units for my tool kit. 

    The pmillet is a DIY one thou. Parts are roughly 200$ total, which includes the custom PCB from ebay. You can select your measurement range from 200mV to 200V in 10x steps and it's very clean. It basically turns your PC into and Oscilloscope if you have the right software (which I'm still looking for).

    You can read more about it here.

  17. In the end, audio engineers keep in mind what the average system looks like, which the mix will be played on. I'm pretty sure the average Atmos system is expected to have a beefier sub than your average consumer HT system. The mix is usually optimized to sound as good as possible on as many systems as possible, plus minus human error.

    Of course this is only a small factor, contributing to the whole, but it's certainly one of the reasons why low-cuts are used.

  18. 8 hours ago, menace said:

    I would though say that less plies will almost always be worse!

    As for Baltic vs other birch, this should be an important distinguishing factor and having not seen the other birch ply i would imagine they should not be compared. Wikipedia list 50+ species with in the genus and imagine there will be chalk and cheese like differences among them. Growth rate according to geographic location and the correct species will mean everything!

    All I know about plywood is that it seems that there is no low quality plywood on the German market, since whatever I buy, it's always void free etc. There are some occasional surface patches but these are really just a visual impairment. I'm currently only interested in trying out Banova ply, but the supplier I'm working with discontinued these and I haven't found any other supplier in my immediate area, which I could get a sample piece from. Still dreaming about the 100lbs SKHorn.

  19. 53 minutes ago, radulescu_paul_mircea said:

    http://www.atelier-der-tonkunst.de/produkte/pol-ddi

    This is the link to the product. Really good and very low distortion. Capable of taking 200 Vrms at under 1% THD is super useful. I tested it for limiter settings and it works as it should. I will try to get my hand around on how to use it for live Impedance monitoring. That would help me a lot

    What a funny coincidence, this device looks like a slightly less fancy version of the pmillet sound card interface, which notnyt from AVS sent me a few weeks ago. I will also use it for amp testing.

  20. 12 hours ago, menace said:

    It has to be said that you Europeans are very lucky being so close to the baltic. The story in new zealand is very different, 18mm mdf 25 euro and 18mm BB ply 110 euro(2440x1220 sheets).

    I pay about 80€ for a sheet of 18mm BB (2500x1250), but why the hell is your MDF so cheap? I pay about 45€ for the same amount of MDF (19mm, 18mm MDF doesn't seem to exist)

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